Internal Medicine

Emergency medical personnel transport an elderly resident from an assisted living facility to the acute medical unit. The staff reported a three-day decline in functional status, noting increased thirst, frequent urination, and an escalating, non-productive cough. Medical records indicate long-standing insulin-requiring diabetes mellitus and severe chronic obstructive pulmonary disease.

Upon arrival, the patient is somnolent but appropriately follows simple commands. Vital signs reveal a temperature of 37.0°C (98.6°F), heart rate of 118/min, blood pressure of 105/62 mm Hg, and a respiratory rate of 28/min with shallow, labored breathing. Oxygen saturation is 90% on ambient air. Physical examination demonstrates poor skin turgor, prominent use of accessory muscles of respiration, and diffuse expiratory wheezing with a prolonged expiratory phase. Jugular venous pressure is estimated at 4 cm H2O.

Initial laboratory studies are obtained:

Arterial blood gas analysis on ambient air:

In addition to intravenous fluid resuscitation and a continuous regular insulin infusion, which of the following is the most appropriate next step in the management of this patient?

A $25$-year-old man presents to the clinic with a diffuse maculopapular rash on his trunk, palms, and soles, along with generalized lymphadenopathy. He reports having a painless penile ulcer $2$ months ago that resolved on its own. Assuming the traditional testing algorithm is used, arrange the following steps in the most appropriate chronological sequence for the diagnosis and management of this patient's condition.

A 55-year-old man receiving systemic chemotherapy for diffuse large B-cell lymphoma presents to the emergency department with chills and a temperature of 38.8°C (101.8°F). His laboratory evaluation reveals an absolute neutrophil count of 400/mm³. Arrange the following clinical interventions in the correct chronological sequence for the standard initial management of this patient's neutropenic fever.

During a routine follow-up evaluation, a 32-year-old woman with diffuse cutaneous systemic sclerosis reports severe pain and discoloration in her digits. She notes that exposure to cold temperatures triggers her fingers to turn sharply white, then blue, and finally red. Arrange the following therapeutic interventions in the correct step-wise sequence for the management of this patient's Raynaud phenomenon, proceeding from initial conservative measures to therapies reserved for severe, refractory, or tissue-threatening disease.

A daughter brings her 75-year-old father to the emergency department due to his profound sleepiness and labored breathing over the preceding 72 hours. The patient has developed a worsening cough productive of yellow sputum and subjective fevers during this time. His medical history includes chronic obstructive pulmonary disease (COPD), benign prostatic hyperplasia, and essential hypertension. His home medications are a tiotropium inhaler, as-needed albuterol, and amlodipine.

Vital signs show a temperature of $37.7^\circ\text{C}$ ($99.9^\circ\text{F}$), blood pressure of $118/74\text{ mm Hg}$, pulse of $108/\text{min}$, and respiratory rate of $26/\text{min}$. Pulse oximetry reveals an oxygen saturation of $85\%$ on room air.

Physical examination demonstrates a somnolent patient who awakens easily to verbal stimuli and follows simple commands. The anteroposterior chest diameter is increased. Auscultation reveals a prolonged expiratory phase with diffuse wheezing bilaterally, as well as coarse crackles localized to the right lower lung field. Cardiac examination shows a regular tachycardia with distant heart sounds and no murmurs. Trace bilateral ankle edema is present.

Laboratory results are as follows:

An arterial blood gas analysis obtained on room air demonstrates:

A portable chest radiograph displays hyperinflated lung fields, flattened hemidiaphragms, and a dense alveolar opacity in the right lower lobe. The cardiac silhouette is normal in size.

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

A 41-year-old woman is brought to the emergency department by her husband due to a 4-day history of profound fatigue, easy bruising, and recurrent nosebleeds. She has no significant past medical history and takes no medications. Vital signs show a temperature of $37.6^\circ \text{C}$ ($99.7^\circ \text{F}$), pulse of $110$/min, respirations of $18$/min, and blood pressure of $105/65$ mm Hg. Physical examination reveals pale mucous membranes, diffuse petechiae over the trunk and extremities, and continuous oozing of blood from a peripheral intravenous catheter site.

Laboratory studies reveal the following:

* Hemoglobin: $7.6$ g/dL
* Leukocyte count: $3,200/\mu\text{L}$
* Platelet count: $18,000/\mu\text{L}$
* Prothrombin time: $22$ seconds
* Activated partial thromboplastin time: $48$ seconds
* Fibrinogen: $80$ mg/dL (Normal: $200$–$400$ mg/dL)
* D-dimer: $8,500$ ng/mL (Normal: $< 500$ ng/mL)

Peripheral blood smear demonstrates large mononuclear cells with bilobed nuclei and abundant azurophilic granules; several of these cells contain multiple, needle-like eosinophilic inclusion bodies.

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

Correlate each complex clinical scenario with the specific autoantibody marker that best corresponds to the patient's underlying rheumatologic diagnosis.

A 54-year-old woman presents to the outpatient clinic reporting a three-week history of progressively worsening exertional dyspnea, fatigue, and bilateral lower extremity swelling. She states that she now requires three pillows to sleep comfortably at night without waking up short of breath. Her medical history is significant for estrogen-receptor-negative, HER2-positive breast cancer, for which she underwent surgical resection and completed a chemotherapy regimen containing doxorubicin and cyclophosphamide six months ago. She is currently receiving maintenance therapy with trastuzumab. Vital signs show a temperature of $37.1^\circ C$ ($98.8^\circ F$), heart rate of $105\text{ /min}$, respiratory rate of $22\text{ /min}$, and blood pressure of $114/74\text{ mmHg}$. Pulse oximetry is $94\%$ on room air. Physical examination reveals an elevated jugular venous pressure of $9\text{ cm H}_2\text{O}$, fine bibasilar crackles, and a distinct third heart sound ($S_3$). Pitting edema is present to the mid-calves bilaterally.

Recent laboratory studies are as follows:

Which of the following is the most appropriate next step in management?

A 24-year-old woman is brought to the emergency department by her roommate 2 hours after intentionally ingesting a large, unknown quantity of immediate-release acetaminophen tablets. She reports mild nausea but is otherwise asymptomatic. Her temperature is 37.0°C (98.6°F), blood pressure is 118/76 mm Hg, pulse is 88/min, and respirations are 14/min. She is alert, fully oriented, and cooperative. Arrange the following steps in the most appropriate chronological sequence for the evaluation and management of this patient.

Progressive shortness of breath over the past 48 hours prompts a 62-year-old man to seek evaluation at the emergency department. He has a 45-pack-year smoking history, type 2 diabetes mellitus, and essential hypertension. The patient notes that his breathing worsens significantly when he lies flat, forcing him to sleep in a recliner chair. His temperature is 37.2°C (99.0°F), blood pressure is 162/94 mm Hg, pulse is 108/min, and respiratory rate is 24/min. Pulse oximetry shows an oxygen saturation of 90% on room air. Physical examination reveals distended neck veins while sitting at a 45-degree angle. Lung auscultation demonstrates bilateral basilar crackles without wheezing. Cardiac examination reveals a regular tachycardia with a prominent S3 gallop. A chest radiograph demonstrates cardiomegaly and cephalization of pulmonary vessels. Which of the following is the most likely diagnosis?

A 65-year-old woman with a body mass index (BMI) of $32\text{ kg/m}^2$ is diagnosed with osteoarthritis of the right knee after presenting with chronic, progressive knee pain that worsens with activity. Radiographs show joint space narrowing and osteophyte formation. Arrange the following management strategies in the standard chronological order of escalation, from initial conservative therapy to definitive treatment.

Match each of the following highly specific autoantibodies to the rheumatologic condition with which they are most classically associated.

A 34-year-old woman is admitted to the intensive care unit with a 2-day history of progressively worsening fatigue, fever, and confusion. Her husband notes she has been difficult to arouse this morning. Temperature is 38.2°C (100.8°F), blood pressure is 142/88 mmHg, pulse is 112/min, and respirations are 18/min. Physical examination reveals scleral icterus, pale conjunctivae, and diffuse petechiae over the lower extremities. Neurologic examination shows altered mental status but no focal motor deficits. Laboratory studies show:

Thrombotic thrombocytopenic purpura (TTP) is strongly suspected. Arrange the following steps in the most appropriate chronological order for the diagnosis and management of this patient.

Seeking preconception counseling, a 26-year-old woman with a history of systemic lupus erythematosus (SLE) and class III lupus nephritis presents to the outpatient clinic. Her disease is currently in clinical and serologic remission without active proteinuria. She is maintained on a daily regimen of mycophenolate mofetil, hydroxychloroquine, and lisinopril. The patient and her husband are eager to conceive as soon as it is medically safe to do so. Arrange the following clinical steps in the optimal chronological sequence to ensure the best maternal and fetal outcomes.

A $62$-year-old man is hospitalized due to a $4$-week history of low-grade fever, progressive fatigue, and generalized myalgias. He has a history of osteoarthritis and underwent a colonoscopy $2$ months ago for routine screening. His temperature is $38.3^\circ\text{C}$ ($100.9^\circ\text{F}$), blood pressure is $122/74\text{ mm Hg}$, and pulse is $92/\text{min}$. Physical examination reveals a grade $3/6$ holosystolic murmur heard best at the cardiac apex that radiates to the axilla. Splinter hemorrhages are noted on the fingernails of both hands. Laboratory studies show a leukocyte count of $14,000/\text{mm}^3$ and an erythrocyte sedimentation rate of $65\text{ mm/hr}$. A transesophageal echocardiogram demonstrates a $1.2\text{-cm}$ mobile vegetation on the mitral valve.

Three sets of blood cultures are drawn, and the patient is empirically started on intravenous vancomycin and ceftriaxone. Forty-eight hours later, all three blood culture sets grow *Enterococcus faecalis*. Antimicrobial susceptibility testing is reported as follows:

The patient's serum creatinine is $0.9\text{ mg/dL}$. He has no known drug allergies. Which of the following is the most appropriate next step in antimicrobial therapy?

A $45$-year-old woman is brought to the emergency department due to sudden-onset, severe weakness in her arms and legs. She reports she could not get out of bed this morning. She has a $3$-year history of a "sand-like" sensation in her eyes, dry mouth requiring frequent sips of water, and intermittent pain in her fingers. She takes no medications. Vital signs are normal. Physical examination shows flaccid paralysis of all four extremities with absent deep tendon reflexes. Sensation is intact.

Laboratory studies show:
Serum sodium: $140 \text{ mEq/L}$
Serum potassium: $1.6 \text{ mEq/L}$
Serum chloride: $116 \text{ mEq/L}$
Serum bicarbonate: $12 \text{ mEq/L}$
BUN: $14 \text{ mg/dL}$
Creatinine: $0.9 \text{ mg/dL}$

Arterial blood gas (room air):
pH: $7.22$
pCO $_2$: $26 \text{ mm Hg}$

Urinalysis:
pH: $6.5$
Specific gravity: $1.015$
Glucose: negative
Protein: negative

Which of the following is the most likely underlying mechanism for this patient's acute presentation?

A $34$-year-old female teacher comes to the primary care office complaining of severe throat pain and a fever that began abruptly yesterday. She notes difficulty swallowing but denies having a cough or rhinorrhea. Her temperature is $38.7^\circ\text{C}$ ($101.7^\circ\text{F}$), blood pressure is $118/76\text{ mmHg}$, and pulse is $92/\text{min}$. Physical examination reveals marked pharyngeal erythema, bilateral tonsillar exudates, and tender anterior cervical lymphadenopathy. A rapid antigen detection test is positive for Streptococcus pyogenes (Group A Streptococcus). The patient has no known drug allergies. Which of the following is the most appropriate next step in pharmacologic management?

A 58-year-old man comes to the urgent care clinic complaining of severe left knee pain that awoke him from sleep. He has a medical history of hypertension and heart failure with preserved ejection fraction, for which he takes lisinopril and hydrochlorothiazide. His temperature is $37.9^\circ\text{C}$ ($100.2^\circ\text{F}$). Physical examination reveals a swollen, erythematous, and exquisitely tender left knee with limited range of motion. There are no other joint abnormalities. Laboratory testing reveals a serum uric acid level of $5.8 \text{ mg/dL}$ (reference: $4.0-8.5 \text{ mg/dL}$). A diagnostic arthrocentesis is performed; synovial fluid analysis shows a leukocyte count of $42,000/\text{mm}^3$ with $85\%$ neutrophils, and the presence of needle-shaped, negatively birefringent crystals. Gram stain reveals no organisms. Which of the following is the most appropriate next step in management?

Match each classic peripheral blood smear or bone marrow finding to its most likely associated hematologic diagnosis.

A $34$-year-old woman comes to the outpatient medical clinic reporting a $6$-month history of progressive fatigue, weakness, and a $4.5\ \text{kg}$ ($10\ \text{lb}$) weight gain. She notes that her menstrual periods, which were previously regular, have ceased entirely over the same timeframe. She takes no medications and has no other medical history. Vital signs show a temperature of $36.4^\circ\text{C}$ ($97.5^\circ\text{F}$), pulse of $54/\text{min}$, and blood pressure of $100/65\ \text{mm Hg}$. Physical examination reveals dry skin and a delayed relaxation phase of the deep tendon reflexes. The thyroid gland is not palpable. A urine pregnancy test is negative.

Laboratory results are as follows:

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