Patient Management

2074 questions

Question 1801Question →

A 20-year-old male college student is brought to the emergency department by his roommates due to a 12-hour history of severe generalized headache, subjective fever, and increasing confusion. He vomited three times prior to arrival. His past medical history is unremarkable, and he takes no medications. On presentation, his temperature is 39.5°C (103.1°F), blood pressure is 95/60 mmHg, heart rate is 122/min, and respiratory rate is 22/min. Physical examination reveals a lethargic patient who opens his eyes to pain and is oriented only to his name. Nuchal rigidity is present. A non-blanching, purpuric rash is noted on his lower extremities. Pupils are equal and reactive to light. There are no focal motor deficits.

Along with the immediate administration of empiric intravenous antibiotics and dexamethasone, which of the following are the most appropriate initial diagnostic studies to perform at this time? (Select the TWO most appropriate options)

Select all that apply

Show answer & explanation

Answer: Two sets of blood cultures from separate venipuncture sites; Non-contrast computed tomography of the head

Answer

The most appropriate initial diagnostic steps are obtaining two sets of blood cultures and performing a non-contrast computed tomography of the head.
This patient presents with a hyperacute onset of fever, headache, nuchal rigidity, altered mental status, and a purpuric rash, which is highly suspicious for acute bacterial meningitis with meningococcemia. The immediate priorities are stabilization and rapid diagnosis. Blood cultures should always be obtained immediately before or concurrently with the administration of empiric antibiotics to maximize the chances of isolating the pathogen. Furthermore, while cerebrospinal fluid analysis via lumbar puncture is required for definitive diagnosis, this patient exhibits altered mental status (lethargic, oriented only to name). Current Infectious Diseases Society of America (IDSA) guidelines mandate that patients with suspected meningitis and specific 'red flag' criteria (altered mental status, papilledema, focal neurological deficits, new-onset seizures, or immunocompromised state) must undergo a screening non-contrast CT of the head prior to a lumbar puncture. This sequenced approach is crucial to rule out intracranial mass effect and prevent fatal cerebral herniation. Therefore, securing blood cultures and obtaining a head CT are the most appropriate initial diagnostic studies to perform concurrently with therapeutic stabilization.

Step-by-Step Solution

1
Evaluate the clinical presentation and identify the primary suspected diagnosis.
The patient has classic signs of acute bacterial meningitis (fever, headache, nuchal rigidity, purpuric rash) complicated by sepsis (hypotension, tachycardia) and altered mental status (lethargy).
Recognizing the life-threatening nature of meningococcemia dictates the urgency and sequence of the diagnostic workup.
2
Determine the required diagnostic tests for the suspected condition.
Blood cultures and cerebrospinal fluid (CSF) analysis via lumbar puncture are the gold standard for diagnosing bacterial meningitis.
Microbiological diagnosis is essential for tailoring targeted antimicrobial therapy.
3
Apply clinical guidelines to sequence the diagnostic tests safely.
Because the patient has altered mental status, a non-contrast CT of the head must be performed before the lumbar puncture.
Altered mental status is a warning sign for potential increased intracranial pressure. Performing a lumbar puncture without prior neuroimaging risks precipitating fatal brainstem herniation.

Key Concept

In patients with suspected acute bacterial meningitis, those with specific risk factors—such as altered mental status, focal neurological deficits, new-onset seizures, papilledema, or an immunocompromised state—must undergo a non-contrast head CT to rule out mass effect prior to a lumbar puncture. Concurrently, blood cultures should be drawn and empiric antibiotics initiated immediately.
Estimated Time:1m 30s
Question 1802Question →

A 48-year-old woman comes to the clinic for a routine health maintenance examination. She has a history of systemic lupus erythematosus (SLE) that is well-controlled. Her daily medications include mycophenolate mofetil and 15 mg of prednisone, which she has been taking for the past three years. She is a former smoker with a 22-pack-year history, having quit 4 years ago. She has no new complaints today and feels well. Her last screening mammogram was performed 3 years ago and was normal. A screening colonoscopy was performed at age 45 and revealed no polyps or abnormalities. Cervical cytology with human papillomavirus (HPV) co-testing was performed 2 years ago and was normal. She received an inactivated influenza vaccine at a local pharmacy two weeks ago and has completed all routine childhood immunizations. She has never received a pneumococcal or herpes zoster vaccine.

Which of the following preventive interventions are indicated for this patient at today's visit? (Select all that apply)

Select all that apply

Show answer & explanation

Answer: Administration of the recombinant zoster vaccine; Administration of the 20-valent pneumococcal conjugate vaccine; Screening mammography

Answer

The correct interventions are the administration of the recombinant zoster vaccine, administration of the 20-valent pneumococcal conjugate vaccine, and screening mammography.
The correct answers are the administration of the recombinant zoster vaccine, administration of the 20-valent pneumococcal conjugate vaccine, and screening mammography. This patient is considered severely immunocompromised due to her daily use of mycophenolate mofetil and moderate-dose prednisone for SLE. According to the Advisory Committee on Immunization Practices (ACIP), the recombinant zoster vaccine is recommended for adults aged 19 years and older who are immunocompromised. Similarly, the 20-valent pneumococcal conjugate vaccine (PCV20) is indicated for adults aged 19 to 64 years with immunocompromising conditions who have not previously received a pneumococcal vaccine. Finally, updated USPSTF guidelines recommend biennial screening mammography for women starting at age 40. Since her last mammogram was 3 years ago, she is overdue for breast cancer screening.

Step-by-Step Solution

1
Identify the patient's immune status based on her medication regimen.
The patient is severely immunocompromised due to chronic use of mycophenolate mofetil and moderate-dose prednisone (15 mg).
Immunocompromised status alters standard ACIP age cutoffs for several critical adult vaccines.
2
Evaluate the indication for specific vaccines.
The recombinant zoster vaccine and 20-valent pneumococcal conjugate vaccine (PCV20) are required.
ACIP recommends both RZV and PCV20 for immunocompromised adults aged 19 years and older, overriding the standard age-based triggers (50 and 65 years, respectively).
3
Assess the patient's breast cancer screening status against current USPSTF guidelines.
Screening mammography is indicated today.
USPSTF recommends biennial screening mammography starting at age 40. Because her last mammogram was 3 years ago (at age 45), she is overdue.
4
Evaluate indications for lung, cervical, and colorectal cancer screenings based on age and previous test intervals.
LDCT, cervical co-testing, and colonoscopy are not indicated today.
She does not meet the age cutoff for LDCT (50 years). Her previous cervical and colorectal screenings were normal and are within their respective 5-year and 10-year safe intervals.

Key Concept

Application of modified preventive screening and immunization schedules for adults with iatrogenic immunosuppression.
Question 1803Question →

A 48-year-old woman presents to her primary care physician for a routine health maintenance examination. She reports feeling generally well but mentions experiencing occasional episodes of a racing heartbeat over the past two months. She has no significant past medical history and takes no medications. Vital signs show a blood pressure of 130/80 mm Hg, heart rate of 98/min, and respiratory rate of 14/min. Physical examination reveals a palpable, mobile, non-tender mass in the right anterior neck. No cervical lymphadenopathy is appreciated. A targeted ultrasound of the neck demonstrates a 2.4-cm solid, isoechoic nodule in the right lobe of the thyroid gland with no microcalcifications. Laboratory studies are ordered, which reveal a serum thyroid-stimulating hormone (TSH) level of 0.08 mU/L (normal: 0.4-4.0 mU/L) and a free thyroxine (T4) level of 2.2 ng/dL (normal: 0.9-1.7 ng/dL). Which of the following is the most appropriate next step in the diagnostic workup of this patient?

Show answer & explanation

Answer: Radionuclide thyroid scintigraphy

Answer

Radionuclide thyroid scintigraphy
The most appropriate next step in the diagnostic workup for a patient with a thyroid nodule and a concomitantly suppressed TSH is radionuclide thyroid scintigraphy (e.g., Iodine-123 or Technetium-99m scan). This step determines if the nodule is hyperfunctioning ('hot') or non-functioning ('cold'). Hyperfunctioning nodules are rarely malignant and generally do not require fine-needle aspiration (FNA). If the scan shows the nodule is 'cold', an FNA would then be indicated based on ultrasound characteristics.

Step-by-Step Solution

1
Evaluate the clinical and laboratory presentation.
The patient has a palpable 2.4-cm thyroid nodule accompanied by a suppressed TSH and elevated free T4.
Identifying the initial clinical data dictates the algorithm for evaluating a thyroid nodule.
2
Determine the proper diagnostic pathway based on the TSH level.
Because the TSH is below normal (suppressed), the functional status of the nodule must be evaluated before considering any invasive testing.
Hyperfunctioning nodules (which cause a suppressed TSH) are extremely rarely malignant and therefore do not typically require biopsy.
3
Select the appropriate test to assess nodule function.
A radionuclide thyroid scan is selected.
Scintigraphy will differentiate a 'hot' nodule (e.g., toxic adenoma) from a 'cold' nodule (which would require a biopsy).

Key Concept

The initial evaluation of a newly discovered thyroid nodule requires concurrent TSH measurement and ultrasound. If the TSH is suppressed, radionuclide scintigraphy is the mandatory next step to assess whether the nodule is hyperfunctioning.
Question 1804Question →

An emergent surgical consultation is requested for a 62-year-old male with acute-onset, severe left lower quadrant abdominal pain. The pain began roughly 24 hours prior and is now unrelenting. Vital signs reveal a temperature of 38.6°C (101.5°F), blood pressure of 105/65 mmHg, heart rate of 110/min, and respiratory rate of 18/min. The abdomen is exquisitely tender in the left lower quadrant with involuntary guarding and rebound tenderness. Laboratory analysis is notable for a leukocyte count of 16,500/mm³ with 85% neutrophils. A contrast-enhanced computed tomography scan of the abdomen and pelvis shows marked diverticular inflammation, a 3-cm pericolic fluid collection, and locules of extraluminal air. The patient is being prepared for the operating room. He has no known medication allergies. In addition to intravenous fluid resuscitation, which of the following antimicrobial regimens are appropriate for empiric management in this patient? (Select all that apply)

Select all that apply

Show answer & explanation

Answer: Piperacillin-tazobactam; Ceftriaxone and metronidazole

Answer

The appropriate empiric antimicrobial regimens for a complicated intra-abdominal infection include single-agent Piperacillin-tazobactam or the combination of Ceftriaxone and metronidazole.
The patient has a complicated intra-abdominal infection secondary to a perforated diverticulum. Infections originating from the lower gastrointestinal tract are polymicrobial and predominantly involve enteric Gram-negative bacilli (e.g., Escherichia coli) and anaerobic bacteria (e.g., Bacteroides fragilis). Empiric pharmacologic intervention must therefore include agents active against both. Piperacillin-tazobactam provides excellent single-agent coverage for these pathogens. A combination of a third-generation cephalosporin (ceftriaxone) plus metronidazole also provides robust coverage against both Gram-negative organisms and anaerobes. Both are standard-of-care options.

Step-by-Step Solution

1
Diagnose the patient's acute condition based on clinical and radiological findings.
The patient has a perforated diverticulum, which is classified as a complicated intra-abdominal infection.
Establishing the anatomical source of the infection is necessary to predict the likely microbial pathogens.
2
Identify the primary microbial flora responsible for infections originating from the lower gastrointestinal tract.
The infection is typically polymicrobial, driven by enteric Gram-negative bacilli (e.g., Escherichia coli, Klebsiella) and anaerobes (e.g., Bacteroides fragilis).
Empiric antimicrobial therapy must be broad enough to target the most likely offending organisms.
3
Select antimicrobial regimens that provide adequate coverage against the identified flora while considering modern resistance patterns.
Piperacillin-tazobactam or ceftriaxone combined with metronidazole effectively cover these pathogens and are guideline-recommended.
These regimens successfully eradicate aerobic Gram-negative and anaerobic pathogens without the high resistance rates associated with older therapies.

Key Concept

Empiric antimicrobial therapy for complicated intra-abdominal infections must provide reliable coverage against both enteric Gram-negative bacilli and anaerobes, utilizing regimens like piperacillin-tazobactam or a third-generation cephalosporin plus metronidazole.
Question 1805Question →

Match the following clinical presentations and risk stratification scores to their most appropriate initial care setting and disposition plan.

Click a left item, then click its matching right item

Items

A 35-year-old evaluated for a 2-day history of productive cough, fever, and focal crackles. Laboratory results and vital signs yield a CURB-65 score of 0 and a Pneumonia Severity Index (PSI) Class I.
A 75-year-old with radiographically confirmed pneumonia presenting with acute confusion, a respiratory rate of 34/min, blood urea nitrogen of 28 mg/dL, and a blood pressure of 85/55 mm Hg, yielding a CURB-65 score of 4.
A 68-year-old presenting with typical anginal chest pain, dynamic ischemic electrocardiogram changes, and elevated cardiac troponin levels, generating a HEART score of 8.
A 72-year-old evaluated for a brief episode of unilateral right-sided weakness and aphasia that completely resolved within 30 minutes, accompanied by a blood pressure of 150/90 mm Hg and a history of type 2 diabetes mellitus, resulting in an ABCD2 score of 6.

Matches

Show answer & explanation

Answer

The low-risk pneumonia patient is discharged to residence; the high-risk pneumonia patient is transferred to the intensive care unit; the high-risk chest pain patient is admitted to a telemetry unit; and the high-risk transient ischemic attack patient is admitted for rapid neurological workup.
Risk stratification scores guide disposition by predicting mortality and adverse events. Low-risk pneumonia (PSI Class I) is safely managed in an outpatient setting. Severe pneumonia (CURB-65 of 4) requires intensive care unit support. High-risk chest pain (HEART score of 8) needs telemetry admission and likely early angiography. High-risk transient ischemic attack (ABCD2 of 6) requires prompt inpatient stroke evaluation.

Step-by-Step Solution

1
Evaluate the 35-year-old patient with pneumonia and a PSI Class I or CURB-65 of 0.
Identify this as very low-risk pneumonia.
Clinical guidelines recommend outpatient management for patients with a PSI Class I to avoid unnecessary hospital exposure and resource utilization.
2
Assess the 75-year-old patient with pneumonia and a CURB-65 score of 4.
Identify severe community-acquired pneumonia with high mortality risk.
A score of 4 (positive for Confusion, Urea > 20, RR > 30, BP < 90/60, and Age > 65) mandates intensive care unit admission for aggressive support.
3
Analyze the 68-year-old patient with a HEART score of 8.
Categorize as high risk for major adverse cardiac events.
Patients with high HEART scores (7-10) require admission to an inpatient telemetry unit and an early invasive strategy, such as angiography.
4
Review the 72-year-old patient with a transient ischemic attack and an ABCD2 score of 6.
Recognize a high immediate risk for a subsequent acute ischemic stroke.
An ABCD2 score of 6 warrants prompt hospital admission to expedite neuroimaging, carotid evaluation, and optimize secondary stroke prevention.

Key Concept

Utilizing validated risk stratification tools (e.g., CURB-65, PSI, HEART, ABCD2) is essential for determining the most appropriate care setting and safe disposition for patients presenting with acute medical conditions.
Question 1806Question →

A 42-year-old female patient is evaluated in the outpatient clinic for progressive weight gain, proximal muscle weakness, and easy bruising developing over the past 14 months. Physical examination reveals central adiposity, facial plethora, and wide violaceous abdominal striae. Her blood pressure is 158/96 mmHg. A diagnosis of endogenous hypercortisolism (Cushing syndrome) is suspected. Arrange the following diagnostic steps in the most appropriate sequential order to establish the diagnosis and identify its underlying etiology.

Drag items to arrange them in the correct order

Show answer & explanation

Answer

The correct diagnostic sequence begins with confirming hypercortisolism, followed by measuring ACTH to determine dependence, then obtaining a pituitary MRI, and finally performing inferior petrosal sinus sampling if the MRI is inconclusive.
The diagnostic algorithm for Cushing syndrome requires a tiered, stepwise approach to prevent diagnostic errors caused by incidental findings on imaging. The sequence mandates establishing the diagnosis of hypercortisolism first (via urine free cortisol or salivary cortisol). Only after hypercortisolism is confirmed should a plasma ACTH level be evaluated to differentiate ACTH-dependent from ACTH-independent causes. If the condition is ACTH-dependent, a pituitary MRI is indicated to localize an adenoma. If the MRI is negative or equivocal, inferior petrosal sinus sampling (IPSS) is the definitive test to distinguish Cushing disease from ectopic ACTH syndrome.

Step-by-Step Solution

1
Confirm the clinical suspicion of endogenous hypercortisolism.
Perform screening with a 24-hour urine free cortisol, late-night salivary cortisol, or a low-dose dexamethasone suppression test.
Clinical features of Cushing syndrome can overlap with common conditions like obesity and metabolic syndrome; biochemical confirmation of excess cortisol is mandatory before proceeding.
2
Determine the source of excess cortisol production (ACTH-dependent vs. ACTH-independent).
Measure plasma ACTH concentration.
A suppressed ACTH level indicates an adrenal source (requiring adrenal imaging), while a normal or elevated ACTH level indicates a pituitary or ectopic source.
3
Localize the ACTH-dependent source.
Obtain an MRI of the pituitary gland.
The most common cause of ACTH-dependent Cushing syndrome is a pituitary adenoma (Cushing disease). MRI is the preferred non-invasive modality to identify pituitary lesions.
4
Differentiate pituitary from ectopic ACTH production if imaging is unclear.
Perform bilateral inferior petrosal sinus sampling (IPSS).
Pituitary incidentalomas are common, and small ACTH-secreting adenomas may not be visible on MRI. IPSS confirms the pituitary as the source by comparing central to peripheral ACTH levels before surgery.

Key Concept

The diagnostic algorithm for Cushing syndrome requires a strict sequence: confirm hypercortisolism, establish ACTH dependence, and finally localize the source.
Estimated Time:1m 30s
Question 1807Question →

A 68-year-old woman comes to the clinic for an annual health maintenance examination. She has a history of primary hypertension and osteoarthritis. She underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy at age 48 for symptomatic uterine fibroids. Pathological examination of the uterus and cervix at that time was benign, and her prior cervical cancer screening tests were consistently normal. She recently became sexually active with a new male partner.

Her most recent colonoscopy was performed at age 62 and revealed no polyps or abnormalities. She underwent a screening mammogram and a dual-energy x-ray absorptiometry (DXA) scan three months ago, both of which were within normal limits. She has a 40-pack-year history of smoking but successfully quit 10 years ago. She currently takes lisinopril and acetaminophen as needed. Vital signs are within normal limits.

Which of the following is the most appropriate next step in screening for this patient?

Show answer & explanation

Answer: Low-dose computed tomography of the chest

Answer

The most appropriate next step in screening is low-dose computed tomography of the chest.
The US Preventive Services Task Force (USPSTF) recommends annual screening for lung cancer with low-dose computed tomography (LDCT) in adults aged 50 to 80 years who have a 20 pack-year or greater smoking history and who currently smoke or have quit within the past 15 years (Grade B recommendation). This patient is 68 years old, has a 40 pack-year smoking history, and quit 10 years ago. Therefore, she precisely meets the criteria for annual LDCT screening.

Step-by-Step Solution

1
Analyze the patient's demographics, smoking history, and surgical history.
The patient is a 68-year-old female with a 40 pack-year smoking history who quit 10 years ago. She had a total hysterectomy for benign disease and a normal colonoscopy 6 years ago.
Identifying specific clinical parameters and timelines is essential to applying age- and risk-based screening guidelines accurately.
2
Evaluate the indication for lung cancer screening.
The patient meets all criteria for annual low-dose computed tomography (LDCT).
USPSTF guidelines strongly recommend (Grade B) annual LDCT for adults aged 50-80 with a 20 pack-year or greater smoking history who currently smoke or have quit within the last 15 years.
3
Rule out competing screening modalities based on guidelines and patient history.
Pap testing is contraindicated post-total hysterectomy; FIT is unnecessary within the 10-year colonoscopy interval; AAA screening is Grade I for women; and ovarian screening is Grade D.
Eliminating distractors ensures that the single, strongly evidence-based (Grade A or B) screening intervention is selected.

Key Concept

Application of age- and risk-stratified USPSTF preventive screening guidelines in primary care, specifically differentiating indications based on surgical history, gender, and smoking status.
Question 1808Question →

A 68-year-old man comes to the clinic for a routine follow-up examination. He has a history of nonvalvular atrial fibrillation, heart failure with reduced ejection fraction (LVEF 35%), and hyperlipidemia. One month ago, he was diagnosed with active pulmonary tuberculosis and was started on a standard four-drug regimen consisting of rifampin, isoniazid, pyrazinamide, and ethambutol. His other daily medications include apixaban, lisinopril, carvedilol, and atorvastatin. Vital signs today are temperature 37.0°C (98.6°F), blood pressure 122/80 mmHg, heart rate 72/min, and respiratory rate 16/min. Physical examination is unremarkable. Laboratory studies, including renal and hepatic function panels, are within normal limits. Which of the following is the most appropriate modification to this patient's pharmacologic regimen?

Show answer & explanation

Answer: Transition apixaban to warfarin

Answer

The most appropriate modification is to transition the patient from apixaban to warfarin.
The patient is taking rifampin, a potent inducer of the cytochrome P450 3A4 (CYP3A4) enzyme and the P-glycoprotein (P-gp) efflux transporter. Apixaban, a direct oral anticoagulant (DOAC), is metabolized by CYP3A4 and is a substrate for P-gp. Concomitant use of rifampin significantly decreases apixaban plasma concentrations, leading to subtherapeutic anticoagulation and an increased risk of cardioembolic stroke. When patients require concurrent treatment with strong CYP3A4/P-gp inducers, DOACs are generally avoided as empiric dose adjustments are not validated or recommended. The most appropriate strategy is to transition the patient to warfarin. Although warfarin metabolism (primarily via CYP2C9) is also induced by rifampin, its anticoagulant effect can be safely and accurately titrated using routine International Normalized Ratio (INR) monitoring.

Step-by-Step Solution

1
Identify the critical drug-drug interaction in the patient's current medication regimen.
Rifampin is a potent inducer of CYP3A4 and P-glycoprotein, which will significantly reduce the serum concentration of apixaban.
Recognizing pharmacokinetic interactions is essential to prevent therapeutic failure, which in this case would leave the patient at a high risk for a cardioembolic stroke.
2
Determine the appropriate alternative anticoagulant for stroke prophylaxis.
Warfarin is selected because its anticoagulant effect can be directly measured and titrated via the International Normalized Ratio (INR).
Although warfarin metabolism is also induced by rifampin, the ability to monitor INR allows the clinician to safely increase the warfarin dose to maintain therapeutic anticoagulation, unlike direct oral anticoagulants which lack standardized monitoring parameters.

Key Concept

Direct oral anticoagulants (DOACs) are contraindicated with potent CYP3A4 and P-glycoprotein inducers like rifampin due to decreased drug efficacy; warfarin is preferred because its dose can be reliably titrated based on INR monitoring.
Estimated Time:1m 30s
Question 1809Question →

A 54-year-old man with a history of alcohol use disorder and cirrhosis is brought to the emergency department by his daughter after he vomited a large amount of bright red blood at home. In the triage area, he has another massive episode of hematemesis. He appears lethargic and is difficult to arouse. His temperature is 37.1°C (98.8°F), blood pressure is 78/40 mmHg, pulse is 134/min, and respirations are 24/min. Pulse oximetry shows 92% on room air. The patient's skin is cool and clammy. His abdomen is distended with a positive fluid wave.

Which of the following are the most appropriate simultaneous initial steps in the stabilization of this patient? (Select 2 answers)

Select all that apply

Show answer & explanation

Answer: Endotracheal intubation; Insertion of two large-bore peripheral intravenous catheters

Answer

The most appropriate simultaneous initial steps are endotracheal intubation and the insertion of two large-bore peripheral intravenous catheters.
The correct interventions focus on the most immediate, life-threatening aspects of the patient's presentation: loss of airway protection and profound hemorrhagic shock. Endotracheal intubation secures the airway against aspiration of blood in a lethargic patient. Two large-bore peripheral intravenous lines provide the necessary access for rapid, high-volume resuscitation with crystalloids and uncrossmatched blood products, which is critical before moving the patient or attempting endoscopy.

Step-by-Step Solution

1
Assess the patient's airway and breathing status.
The patient has massive ongoing hematemesis and is lethargic (altered mental status), indicating an inability to protect his airway.
Airway compromise is an immediate threat to life in severe upper gastrointestinal bleeding due to the high risk of aspiration.
2
Assess the patient's hemodynamic status.
The patient is in hemorrhagic shock, evidenced by profound hypotension (78/40 mmHg), marked tachycardia (134/min), and cool, clammy skin.
Rapid loss of intravascular volume requires immediate resuscitation to maintain perfusion to vital organs.
3
Determine the necessary initial stabilization interventions.
Airway protection (endotracheal intubation) and securing robust vascular access (two large-bore peripheral IVs) must be performed simultaneously before any diagnostic testing.
These steps address the most immediate life-threatening derangements (ABCs: Airway and Circulation) and lay the foundation for definitive treatment.

Key Concept

In patients with severe upper gastrointestinal bleeding complicated by hemorrhagic shock and altered mental status, initial management must prioritize securing the airway (intubation) and establishing robust intravenous access for rapid volume resuscitation before definitive diagnostic or therapeutic procedures.
Question 1810Question →

For each of the following ambulatory clinical encounters, identify the most appropriate next step in preventive care based on the patient's specific risk factors and demographic profile.

Click a left item, then click its matching right item

Items

An asymptomatic 32-year-old female who was treated with mantle field radiation therapy for Hodgkin lymphoma 14 years ago.
A 67-year-old male with a 40 pack-year smoking history who successfully quit tobacco 8 years ago, whose abdominal ultrasound at age 65 was unremarkable.
A 42-year-old female who recently tested positive for HIV (CD4 count 450 cells/mm³) and has never received any pneumococcal immunizations.
A 45-year-old male of Asian descent presenting for a wellness check with a body mass index of 24 kg/m² and blood pressure of 128/80 mmHg.

Matches

Show answer & explanation

Answer

The clinical scenarios are matched with their corresponding indicated preventive interventions as follows: The patient with prior mantle field radiation requires annual mammography and breast MRI. The 67-year-old former smoker requires annual low-dose CT of the chest. The patient with newly diagnosed HIV requires PCV20. The 45-year-old man of Asian descent with a BMI of 24 kg/m² requires diabetes screening.
Each patient vignette presents a specific risk-enhancing factor, past medical history, or demographic detail that substantially modifies standard preventive care intervals or indications based on current USPSTF and ACIP recommendations.

Step-by-Step Solution

1
Evaluate the 32-year-old female's breast cancer risk profile.
She is classified as high-risk due to prior thoracic radiation exposure.
Thoracic radiation before age 30 necessitates intensive breast cancer screening with annual mammogram and breast MRI, overriding standard average-risk age guidelines.
2
Evaluate the 67-year-old male's ongoing screening requirements.
He needs annual low-dose CT of the chest, but no further abdominal aortic aneurysm (AAA) screening.
He meets the age, pack-year, and cessation time criteria for lung cancer screening. AAA screening is exclusively a one-time ultrasound, which he has already completed.
3
Determine the pneumococcal vaccine indication for the HIV-positive female.
The 20-valent pneumococcal conjugate vaccine (PCV20) is indicated.
Adults aged 19-64 with immunocompromising conditions like HIV require PCV20 (or PCV15 followed by PPSV23) if they are vaccine-naive, regardless of age.
4
Assess the 45-year-old Asian American male's metabolic screening indication.
Diabetes screening is indicated based on his body mass index (BMI).
While the standard BMI threshold for diabetes screening in adults aged 35-70 is 25 kg/m², the threshold is lowered to 23 kg/m² for Asian Americans to account for different body composition risks.

Key Concept

Guideline-based preventive care and screening modifications for high-risk and specific demographic populations
Question 1811Question →

A 6868-year-old man returns to the outpatient clinic for evaluation of persistently elevated blood pressure. He has a history of severe coronary artery disease, for which he underwent coronary artery bypass grafting five years ago, and sick sinus syndrome requiring placement of a dual-chamber permanent pacemaker. His current medications include aspirin, atorvastatin, metoprolol, amlodipine, and lisinopril. The lisinopril was added to his regimen three weeks ago due to uncontrolled hypertension. Today, his blood pressure is 176/98176/98 mm Hg, and his heart rate is 7272/min. Physical examination reveals a soft, high-pitched systolic bruit auscultated just to the right of the umbilicus. Laboratory studies obtained this morning show a serum creatinine level of 2.62.6 mg/dL, an increase from a baseline of 1.41.4 mg/dL recorded one month ago. The estimated glomerular filtration rate (eGFR) is 2424 mL/min/1.731.73 m 2^2. Urinalysis shows no red blood cells or casts. Which of the following is the most appropriate next step in this patient's diagnostic workup?

Show answer & explanation

Answer: Duplex ultrasonography of the renal arteries

Answer

The most appropriate next step is duplex ultrasonography of the renal arteries, as it safely evaluates for renal artery stenosis without utilizing nephrotoxic contrast media.
The correct answer is duplex ultrasonography of the renal arteries. This patient's presentation—resistant hypertension, an abdominal bruit, and an acute, significant increase in serum creatinine following the initiation of an ACE inhibitor—is highly suspicious for atherosclerotic renal artery stenosis (RAS). The initial diagnostic workup for suspected RAS requires noninvasive imaging. Because this patient has stage 4 chronic kidney disease (eGFR <30< 30 mL/min/1.731.73 m 2^2), duplex ultrasonography is the preferred modality. It does not require contrast administration, thereby providing necessary anatomic and hemodynamic information without risking contrast-induced acute kidney injury or nephrogenic systemic fibrosis.

Step-by-Step Solution

1
Analyze the clinical presentation to identify the suspected underlying condition.
The patient has resistant hypertension, a new abdominal bruit, and an acute >30%>30\% increase in serum creatinine following the initiation of an ACE inhibitor (lisinopril). This triad is highly suggestive of bilateral atherosclerotic renal artery stenosis (RAS).
Recognizing the classic clinical syndrome of renovascular hypertension guides the selection of the correct diagnostic pathway.
2
Evaluate the patient's comorbidities and baseline parameters to determine the safest imaging modality.
The patient has an eGFR of 2424 mL/min/1.731.73 m 2^2 (Stage 4 CKD) and an implanted permanent pacemaker.
Diagnostic test sequencing must prioritize patient safety; severe renal impairment and implanted devices dictate which advanced imaging studies are contraindicated.
3
Select the optimal initial diagnostic test based on the identified constraints.
Duplex ultrasonography of the renal arteries is chosen because it is noninvasive, does not require nephrotoxic contrast (unlike CTA), and does not utilize magnetic fields or gadolinium (unlike MRA).
Guidelines recommend duplex ultrasound as the initial screening test of choice for suspected renovascular hypertension in patients with significant renal dysfunction.

Key Concept

In patients with suspected renovascular hypertension and severe chronic kidney disease (eGFR <30< 30 mL/min/1.731.73 m 2^2), duplex ultrasonography of the renal arteries is the most appropriate initial diagnostic test because it avoids the risks of contrast-induced nephropathy and nephrogenic systemic fibrosis.
Question 1812Question →

Following a high-speed motor vehicle collision, a 29-year-old woman is brought to the emergency department by paramedics. Upon arrival, she is unresponsive and has mottled, cool extremities. Vital signs include a heart rate of 145/min, blood pressure of 65/35 mm Hg, and respiratory rate of 36/min. Physical examination reveals that the trachea is markedly deviated to the left. The right hemithorax is expanded, hyperresonant to percussion, and completely lacks audible breath sounds. The jugular veins are significantly distended. Which of the following is the most appropriate immediate next step in management?

Show answer & explanation

Answer: Perform immediate needle thoracostomy

Answer

The most appropriate immediate step is to perform a needle thoracostomy to decompress the tension pneumothorax.
The correct answer is immediate needle thoracostomy. This patient presents in severe obstructive shock following blunt trauma, exhibiting the hallmark clinical signs of a tension pneumothorax: marked hypotension, tachycardia, tracheal deviation, unilateral hyperresonance, absent breath sounds, and jugular venous distention. Tension pneumothorax occurs when a one-way tissue valve allows air to enter the pleural space but not escape. The rapidly accumulating air increases intrathoracic pressure, shifts the mediastinum, and severely compresses the superior and inferior vena cava. This dramatically reduces venous return to the heart, leading to cardiovascular collapse. Because this condition is rapidly fatal, it is strictly a clinical diagnosis; immediate decompression (via needle or finger thoracostomy) must be performed to restore venous return before any diagnostic imaging or other interventions are attempted.

Step-by-Step Solution

1
Analyze the trauma presentation and physical examination findings.
Identified the classic triad of a tension pneumothorax: severe hemodynamic instability, unilaterally absent breath sounds with hyperresonance, and tracheal deviation.
To establish a definitive clinical diagnosis based on physiological signs before considering any diagnostic tests.
2
Determine the underlying mechanism of shock.
Recognized that trapped air is causing elevated intrathoracic pressure, leading to mediastinal shift, compressed vena cavae, and resultant obstructive shock.
Understanding the obstructive nature of the shock explains why fluid or vasopressors will not fix the root cause.
3
Prioritize interventions according to the Advanced Trauma Life Support (ATLS) framework.
Selected immediate mechanical decompression over imaging, fluid resuscitation, or advanced airway management.
In the ATLS primary survey, life-threatening breathing/ventilation issues (like tension pneumothorax) must be resolved immediately upon identification.

Key Concept

Tension pneumothorax is a clinical diagnosis requiring immediate needle or finger thoracostomy for stabilization prior to any radiographic confirmation.
Estimated Time:1m 0s
Question 1813Question →

Match each patient presentation of gastrointestinal bleeding or anemia with the most appropriate next step in diagnostic workup.

Click a left item, then click its matching right item

Items

A 61-year-old man with persistent symptomatic iron deficiency anemia. Recent upper endoscopy and colonoscopy were both unremarkable.
A 54-year-old man with massive, painless hematochezia and hemodynamic instability. Upper endoscopy showed no active bleeding, but brisk hematochezia continues.
A 73-year-old man presenting for routine follow-up after a positive fecal immunochemical test (FIT) obtained during annual health maintenance.
A 39-year-old woman describing sharp anal pain and bright red blood noted exclusively on tissue paper after bowel movements.

Matches

Show answer & explanation

Answer

The clinical scenarios should be matched based on the established algorithms for localizing gastrointestinal bleeding: obscure bleeding warrants small bowel evaluation, massive unstable bleeding requires rapid angiographic localization, positive noninvasive screening mandates full colonic evaluation, and classic anorectal symptoms allow for targeted distal visualization.
Each diagnostic modality has a specific role in the gastrointestinal bleeding algorithm based on chronicity, rate of bleeding, and prior test results. Capsule endoscopy evaluates the small bowel for obscure bleeding. CT angiography localizes rapid, active bleeding in unstable patients. Colonoscopy is the gold standard for routine occult bleeding workup. Anoscopy provides targeted evaluation for distal anorectal pathology.

Step-by-Step Solution

1
Assess the patient's hemodynamic status and chronicity of bleeding.
Unstable patients require rapid localization tools, while stable patients can safely undergo endoscopic evaluation.
Hemodynamic instability dictates the urgency and modality of the intervention.
2
Review prior endoscopic investigations for patients with chronic anemia.
Patients with negative upper and lower endoscopies have 'obscure' bleeding.
The small bowel is the most likely source of bleeding when standard bidirectional endoscopy is normal.
3
Determine the necessity of full colonic evaluation versus targeted distal examination.
A positive FIT requires full colonoscopy to rule out malignancy, whereas isolated bright red blood on tissue paper in a young patient often only requires anoscopy.
Test sequencing must balance diagnostic yield with procedural risk and cost.

Key Concept

Diagnostic algorithms for gastrointestinal bleeding are dictated by hemodynamic stability, bleeding rate, and prior endoscopic findings.
Question 1814Question →

A 71-year-old man is brought to the emergency department from a skilled nursing facility with profound lethargy and fever. His temperature is 39.4°C (102.9°F), heart rate is 128/min, respiratory rate is 24/min, and blood pressure is 74/38 mmHg. Oxygen saturation is 95% on ambient air. Physical examination reveals dry mucous membranes, delayed capillary refill, and suprapubic tenderness. Laboratory studies show a white blood cell count of 19,000/mm³ and a serum lactate of 4.8 mmol/L. Blood and urine cultures are obtained, and broad-spectrum intravenous antibiotics are initiated for suspected urosepsis. The clinical team anticipates a prolonged resuscitation course and outlines a step-wise treatment pathway to maintain a mean arterial pressure (MAP) greater than 65 mmHg. Arrange the following pharmacologic interventions in the correct sequential order of administration according to guideline-directed therapy for septic shock.

Drag items to arrange them in the correct order

Show answer & explanation

Answer

The correct sequence for managing septic shock is: 1) Rapid infusion of 30 mL/kg of balanced crystalloid solution, 2) Initiation of norepinephrine continuous infusion, 3) Addition of vasopressin continuous infusion, and 4) Administration of intravenous hydrocortisone.
The Surviving Sepsis Campaign guidelines dictate a strict sequence for hemodynamic stabilization. The cornerstone of initial therapy is volume expansion with at least 30 mL/kg of intravenous crystalloid within the first 3 hours. If the patient remains hypotensive (MAP < 65 mmHg) after the fluid challenge, a vasopressor is indicated, with norepinephrine being the preferred first-line agent. If the MAP target is still not achieved despite escalating doses of norepinephrine (typically > 0.25-0.5 mcg/kg/min), the addition of a second vasopressor, specifically vasopressin, is recommended to augment blood pressure and decrease the norepinephrine requirement. Finally, if hemodynamic stability cannot be achieved despite adequate fluid resuscitation and vasopressor therapy, intravenous hydrocortisone (typically 200 mg/day) is administered to treat potential critical illness-related corticosteroid insufficiency (CIRCI).

Step-by-Step Solution

1
Evaluate initial hemodynamic status and initiate fluid resuscitation.
A crystalloid bolus is administered.
Intravascular volume depletion must be corrected first to optimize cardiac preload and stroke volume.
2
Re-evaluate the mean arterial pressure (MAP) and initiate the first-line vasopressor.
Norepinephrine is started.
The MAP remains below 65 mmHg despite fluid loading, requiring strong alpha-1 agonism to increase systemic vascular resistance.
3
Escalate vasopressor therapy if the MAP remains sub-target on high-dose primary agents.
Vasopressin is added.
Vasopressin helps achieve MAP goals while sparing escalating doses of norepinephrine and its associated adverse effects (e.g., tachyarrhythmias, profound ischemia).
4
Address potential adrenal insufficiency in refractory shock.
Intravenous hydrocortisone is administered.
Refractory shock unresponsive to adequate fluids and dual vasopressors requires stress-dose steroids to restore vascular responsiveness.

Key Concept

Step-wise pharmacologic management of septic shock
Question 1815Question →

A 59-year-old woman comes to the clinic for a routine health maintenance examination. She has a history of type 2 diabetes mellitus and primary hypertension, which are well-controlled on metformin and lisinopril. She smoked 1.5 packs of cigarettes daily for 20 years but successfully quit at age 43. Her past medical history is otherwise unremarkable. Her last screening colonoscopy was at age 49 and revealed no polyps. She had a normal screening mammogram 1 year ago, and a normal Papanicolaou (Pap) smear with negative human papillomavirus (HPV) co-testing 3 years ago. She has received all age- and risk-appropriate vaccinations, including a Tdap booster 4 years ago and a 20-valent pneumococcal conjugate vaccine (PCV20) at age 55. She currently feels well and has no complaints. Vital signs and physical examination are unremarkable. Which of the following is the most appropriate next step in preventive care for this patient?

Show answer & explanation

Answer: Recommend a screening colonoscopy

Answer

The most appropriate next step is to recommend a screening colonoscopy.
The correct answer is recommending a screening colonoscopy. The USPSTF recommends screening for colorectal cancer in all adults aged 45 to 75 years. For patients at average risk whose previous screening colonoscopy was normal, the recommended interval for repeat screening is 10 years. Because this patient had a normal colonoscopy at age 49 and is currently 59 years old, exactly 10 years have passed, making her due for her next screening.

Step-by-Step Solution

1
Calculate the patient's smoking history and duration since cessation.
The patient has a 30 pack-year history (1.5 packs/day * 20 years). She is currently 59 and quit at age 43, meaning she quit 16 years ago.
Lung cancer screening criteria rely heavily on both the total pack-year history and the exact time elapsed since quitting.
2
Evaluate eligibility for low-dose computed tomography (LDCT).
The patient is ineligible. Although she meets the age (50-80) and pack-year (>=20) criteria, the USPSTF guidelines stipulate that screening should be discontinued once a person has not smoked for 15 years.
Recognizing the 15-year cutoff is critical to avoid unnecessary radiation exposure and false-positive workups.
3
Evaluate the timeline of her prior cancer screenings and immunizations.
Colonoscopy: performed 10 years ago (due now). Mammogram: performed 1 year ago (due every 2 years, up to date). Pap/HPV: performed 3 years ago (due every 5 years, up to date). PCV20: received at age 55 (complete series, up to date).
Preventive care requires applying specific intervals to a patient's historical data to identify current needs.
4
Select the single indicated intervention.
Screening colonoscopy is the only indicated intervention at this visit.
The standard interval for colorectal cancer screening in an average-risk patient following a normal colonoscopy is 10 years.

Key Concept

USPSTF preventive screening intervals and discontinuation criteria, specifically recognizing that lung cancer screening is discontinued 15 years after smoking cessation.
Question 1816Question →

A 45-year-old woman is evaluated in an urgent care clinic for a painful skin lesion on her left lower extremity. She states that she noticed a small "spider bite" three days ago that has progressively enlarged and become exquisitely tender. Her past medical history is notable for major depressive disorder, which is well-controlled on fluoxetine. She was also hospitalized six months ago for severe *Clostridioides difficile* colitis after receiving a course of antibiotics for sinusitis. Her temperature is 37.8°C (100.0°F), blood pressure is 122/78 mm Hg, and pulse is 88/min. Physical examination of the left calf reveals a 4-cm fluctuant nodule surrounded by a 6-cm area of intense erythema, induration, and warmth. Bedside ultrasound confirms a localized fluid collection. An incision and drainage procedure is performed, yielding 20 mL of purulent exudate. Given the significant surrounding cellulitis and the high local prevalence of community-acquired methicillin-resistant *Staphylococcus aureus* (MRSA), the physician decides to initiate empiric oral antibiotic therapy. Which of the following is the most appropriate pharmacologic intervention?

Show answer & explanation

Answer: Trimethoprim-sulfamethoxazole

Answer

Trimethoprim-sulfamethoxazole is the most appropriate choice because it effectively covers community-acquired MRSA while avoiding critical patient-specific risks (interaction with fluoxetine and a history of severe C. difficile).
The correct intervention is Trimethoprim-sulfamethoxazole. For a patient presenting with a purulent skin and soft tissue infection and significant surrounding cellulitis in an area with high MRSA prevalence, empiric oral MRSA coverage is indicated in addition to incision and drainage. Trimethoprim-sulfamethoxazole provides excellent CA-MRSA coverage while avoiding critical patient-specific contraindications: it does not interact with her SSRI (fluoxetine) and carries a comparatively lower risk of precipitating recurrent Clostridioides difficile.

Step-by-Step Solution

1
Identify the primary clinical indication.
The patient has a purulent skin and soft tissue infection with significant surrounding cellulitis, requiring empiric antibiotic coverage for community-acquired MRSA following incision and drainage.
Guidelines recommend systemic MRSA coverage for purulent infections accompanied by systemic signs or significant surrounding cellulitis.
2
Evaluate potential therapeutic options against patient-specific risk factors.
The patient's history includes active fluoxetine use and a recent severe C. difficile infection.
Comorbidities and current medications must be screened to prevent adverse drug events and iatrogenic harm.
3
Select the safest, most effective medication.
Trimethoprim-sulfamethoxazole covers MRSA and avoids both the serotonin syndrome risk of linezolid and the elevated C. difficile recurrence risk of clindamycin.
It fulfills the microbiological requirement while safely navigating the patient's pharmacologic contraindications.

Key Concept

Empiric antibiotic selection must integrate patient-specific risks, such as avoiding linezolid in patients on SSRIs (risk of serotonin syndrome) and avoiding clindamycin in patients with a history of severe Clostridioides difficile colitis.
Question 1817Question →

A 31-year-old male is transported to the trauma center via ambulance following an assault with a sharp object. He sustained a single stab wound to the left anterolateral neck, horizontally aligned with the cricoid cartilage. He appears severely distressed, diaphoretic, and is clutching his neck. His temperature is 36.6∘C36.6^\circ\text{C} (97.9∘F97.9^\circ\text{F}), pulse is 142/min142\text{/min}, blood pressure is 78/42 mm Hg78/42\text{ mm Hg}, and respirations are 32/min32\text{/min}. Oxygen saturation is 90%90\% on ambient air. Physical examination demonstrates a 4-cm4\text{-cm} laceration with pulsatile hemorrhage that is only partially controlled with direct pressure by the emergency responders. A prominent, tense hematoma is visibly enlarging and deviating the larynx to the contralateral side, accompanied by biphasic stridor. Which of the following interventions are mandatory immediate next steps in this patient's procedural management? (Select all that apply.)

Select all that apply

Show answer & explanation

Answer: Endotracheal intubation to secure the airway; Exploratory cervicotomy in the operating suite

Answer

The mandatory immediate next steps are securing the airway with endotracheal intubation and performing an exploratory cervicotomy in the operating suite.
The correct interventions directly address the life-threatening conditions in a patient presenting with penetrating neck trauma and 'hard signs' of vascular or aerodigestive injury. Hard signs include hemodynamic instability (shock), a rapidly expanding or pulsatile hematoma, active severe hemorrhage, massive subcutaneous emphysema, or airway compromise (such as stridor). The presence of any hard sign mandates immediate surgical exploration (cervicotomy) in the operating suite to achieve hemostasis. Additionally, because the expanding hematoma is deviating the trachea and causing symptomatic compression (stridor), securing the airway via endotracheal intubation is a critical concurrent procedural priority before complete anatomical airway obstruction occurs.

Step-by-Step Solution

1
Identify clinical markers of severity in penetrating neck trauma.
The patient exhibits 'hard signs' including hemodynamic instability (shock), an expanding pulsatile hematoma, and airway compromise (stridor).
Hard signs dictate the divergence between medical/diagnostic management and immediate surgical intervention.
2
Determine the optimal sequencing of interventions.
Diagnostic imaging and monitoring must be bypassed in favor of definitive procedural management.
Delays in achieving hemostasis and airway control in patients with hard signs lead to high mortality.
3
Select the appropriate procedural interventions.
Endotracheal intubation and exploratory cervicotomy are chosen.
Intubation prevents imminent loss of the airway from external compression, while cervicotomy provides definitive control of the bleeding source.

Key Concept

Management of penetrating neck trauma with hard signs requires immediate airway stabilization and emergent surgical exploration, bypassing diagnostic imaging.
Question 1818Question →

An 8181-year-old male resident of a memory care facility is transported to the hospital due to progressive abdominal distension and failure to pass stool or flatus for the past three days. He has a history of vascular dementia, Parkinson disease, and chronic constipation. His daily medications include carbidopa-levodopa, donepezil, and scheduled senna. Vital signs show a temperature of 37.1∘37.1^\circ C (98.8∘98.8^\circ F), blood pressure of 134/82134/82 mm Hg, pulse of 9494/min, and respiratory rate of 1818/min. On physical examination, the abdomen is markedly distended and tympanic to percussion. There is generalized mild tenderness to deep palpation, but no guarding, rebound tenderness, or rigidity is noted. Bowel sounds are high-pitched and infrequent. Laboratory testing reveals a leukocyte count of 9,5009,500/mm 3^3 and a serum lactate of 1.11.1 mmol/L. An unenhanced abdominal computed tomography scan demonstrates a massively dilated loop of large bowel forming a U-shape in the pelvis, converging toward the left lower quadrant, accompanied by a mesenteric "whirl sign". No free intraperitoneal air or bowel wall pneumatosis is visualized. Which of the following is the most appropriate next step in management?

Show answer & explanation

Answer: Endoscopic detorsion via flexible sigmoidoscopy

Answer

Endoscopic detorsion via flexible sigmoidoscopy
The correct answer is endoscopic detorsion via flexible sigmoidoscopy. This patient's presentation of progressive abdominal distension and obstipation, combined with CT findings of a massively dilated U-shaped colon and a mesenteric 'whirl sign', is pathognomonic for sigmoid volvulus. Because he is hemodynamically stable, lacks signs of peritonitis, and has normal lactate and leukocyte counts, there is no evidence of underlying bowel ischemia or perforation. In uncomplicated sigmoid volvulus, the most appropriate initial procedural intervention is endoscopic detorsion using a flexible sigmoidoscope, often followed by the placement of a rectal tube to maintain decompression. If successful, this converts an emergent surgical situation into an elective one, allowing for optimization before a definitive sigmoid colectomy is performed to prevent recurrence.

Step-by-Step Solution

1
Analyze the patient's presentation and imaging findings.
The clinical picture of progressive abdominal distension, absent bowel movements, and a CT scan showing a dilated U-shaped colon with a mesenteric 'whirl sign' confirms a diagnosis of sigmoid volvulus.
Establishing the correct diagnosis differentiates this condition from other causes of large bowel obstruction or pseudo-obstruction.
2
Assess for signs of complications such as bowel ischemia or perforation.
The patient is hemodynamically stable, has a normal temperature, normal leukocyte count, normal lactate level, and lacks peritonitis on physical examination. The CT scan shows no pneumoperitoneum.
The presence or absence of ischemic complications directly dictates whether management should be surgical or procedural.
3
Determine the first-line therapeutic procedural intervention for an uncomplicated sigmoid volvulus.
Flexible sigmoidoscopy should be performed to untwist the colon and place a flatus tube for continued decompression.
Endoscopic detorsion is highly successful and avoids the morbidity of emergency abdominal surgery in a high-risk, elderly patient.

Key Concept

The primary management of uncomplicated sigmoid volvulus is emergent endoscopic detorsion, whereas surgical intervention (laparotomy with resection) is reserved for cases with suspected gangrene, perforation, or failed endoscopic reduction.
Estimated Time:1m 15s
Question 1819Question →

An office worker in his late 60s is evaluated in the clinic for three months of non-radiating, deep lower back pain and progressive generalized fatigue. He reports that his pain is worse with movement and has not responded to escalating doses of over-the-counter ibuprofen. He denies fevers, weight loss, or urinary incontinence. His past medical history is notable only for mild osteoarthritis. Vital signs are within normal limits. Physical examination demonstrates marked conjunctival pallor and localized tenderness to palpation over the L3 and L4 spinous processes. Neurological examination, including strength, sensation, and deep tendon reflexes in the lower extremities, is unremarkable. Initial laboratory analysis reveals the following:

* Hemoglobin: 9.4 g/dL
* Mean corpuscular volume: 89 fL
* Leukocyte count: 5,500/mm³
* Platelet count: 165,000/mm³
* Creatinine: 1.8 mg/dL
* Calcium: 11.4 mg/dL

Which of the following diagnostic studies should be ordered concurrently as the most appropriate next steps in this patient's evaluation? (Select three)

Select all that apply

Show answer & explanation

Answer: Serum and urine protein electrophoresis with immunofixation; Serum free light chain assay; Whole-body low-dose computed tomography

Answer

The most appropriate concurrent next steps in this patient's evaluation are serum and urine protein electrophoresis with immunofixation, serum free light chain assay, and whole-body low-dose computed tomography.
This patient presents with the classic 'CRAB' manifestations of multiple myeloma: hypercalcemia, renal insufficiency, anemia, and bone pain (localized to the lumbar spine). The initial diagnostic workup must achieve two goals simultaneously: detecting the underlying plasma cell dyscrasia and evaluating the extent of bone involvement. Current guidelines mandate a concurrent initial panel consisting of serum and urine protein electrophoresis with immunofixation to identify a monoclonal protein (M-spike), a serum free light chain assay to detect light-chain predominant disease, and a whole-body low-dose computed tomography (WBLDCT) scan. WBLDCT has largely replaced the conventional skeletal survey due to its superior sensitivity for detecting osteolytic lesions and impending fractures.

Step-by-Step Solution

1
Analyze the patient's clinical presentation and laboratory findings.
The patient exhibits hypercalcemia, renal insufficiency, normocytic anemia, and bone pain (CRAB criteria).
Identifying the classic CRAB tetrad strongly suggests a diagnosis of multiple myeloma.
2
Determine the initial, non-invasive diagnostic tests required to screen for a plasma cell dyscrasia.
Identify the need for serum/urine protein electrophoresis with immunofixation and a serum free light chain assay.
These concurrent laboratory tests provide a highly sensitive screening panel to detect circulating monoclonal proteins or free light chains.
3
Select the most appropriate initial imaging modality to evaluate for skeletal involvement.
Select whole-body low-dose computed tomography (WBLDCT).
WBLDCT is the current standard-of-care initial imaging test to detect the purely osteoclastic lytic lesions characteristic of multiple myeloma.

Key Concept

The initial diagnostic workup for suspected multiple myeloma requires concurrent testing for monoclonal proteins (using SPEP/UPEP and serum free light chains) and systemic evaluation for osteolytic bone lesions (using whole-body low-dose CT).
Question 1820Question →

Identify the most appropriate initial admission location or post-acute care transition setting for the following clinical scenarios.

Click a left item, then click its matching right item

Items

71-year-old female with community-acquired pneumonia, new-onset confusion, respiratory rate 32/min, BUN 26 mg/dL, and persistent hypotension after IV fluid resuscitation.
58-year-old male presenting with 2 hours of atypical chest pain, non-specific ST changes, normal initial troponin, diabetes mellitus, and hypertension.
82-year-old male recovering from a major ischemic stroke with profound hemiparesis who fatigues rapidly and can only tolerate 30 minutes of physical therapy daily.
65-year-old male with ARDS who is hemodynamically stable but has required mechanical ventilation for 21 days and failed multiple spontaneous breathing trials.

Matches

Show answer & explanation

Answer

The pneumonia patient matches with the Intensive Care Unit (ICU); the chest pain patient matches with the Observation Unit; the stroke patient matches with the Skilled Nursing Facility (SNF); and the ARDS patient matches with the Long-Term Acute Care Hospital (LTACH).
Each patient's disposition is determined by specific risk stratification tools and functional criteria. The pneumonia patient meets criteria for ICU admission due to shock. The chest pain patient requires an observation unit based on a moderate-risk HEART score. The stroke patient needs a SNF due to therapy tolerance limits, and the ARDS patient requires an LTACH for complex ventilator weaning.

Step-by-Step Solution

1
Evaluate the pneumonia patient's severity using clinical criteria.
The patient has a CURB-65 score of 5 and fluid-refractory hypotension.
Severe community-acquired pneumonia with shock requires ICU-level support.
2
Calculate the HEART score for the patient with chest pain.
The patient scores 4 points, indicating moderate risk.
Moderate-risk patients require further evaluation in an Observation Unit rather than immediate discharge or inpatient admission.
3
Assess the functional capacity and therapy tolerance of the stroke patient.
The patient can only tolerate 30 minutes of therapy daily.
Inpatient Rehabilitation Facilities (IRF) require patients to tolerate at least 3 hours of therapy daily; those who cannot must be transitioned to a SNF.
4
Determine the appropriate setting for the ventilator-dependent ARDS patient.
The patient is hemodynamically stable but requires prolonged mechanical ventilation weaning.
LTACHs specialize in weaning patients who have required mechanical ventilation for 21 days or more.

Key Concept

Appropriate care setting disposition relies on matching patient clinical stability, functional capacity, and ongoing medical needs with specific facility capabilities and admission criteria.
PreviousPage 91 / 104Next
Patient Management Practice Questions — USMLE Step 3 — Page 91 | Examkin