Tüm alıştırma soruları

A 45-year-old man is brought to the emergency department by his spouse due to acute-onset confusion, agitation, and profound diaphoresis. His medical history includes major depressive disorder, for which he has taken citalopram for three years, and gastroesophageal reflux disease, managed with daily omeprazole. Ten days ago, he was discharged from the hospital after receiving treatment for a complicated methicillin-resistant *Staphylococcus aureus* (MRSA) cellulitis; he is currently completing a 14-day oral course of linezolid. Over the past 48 hours, he developed severe nausea and began taking ondansetron, which he had left over from a prior prescription. He also reports taking several doses of ibuprofen for a mild headache. On physical examination, his temperature is 39.1°C (102.4°F), blood pressure is 168/96 mm Hg, and pulse is 122/min. Neurologic examination reveals spontaneous ocular clonus, generalized hyperreflexia, and inducible ankle clonus that is most pronounced in the lower extremities. Which of the following agents from this patient's pharmacological history synergistically interact to precipitate his current toxidrome? (Select all that apply)

A primary care physician evaluates a female patient who reports 14 months of progressively worsening deep pain in her ribs and lower extremities. The patient, a 42-year-old architect, also describes profound proximal muscle weakness, noting that she now requires the use of her arms to stand up from a seated position. She has no significant past medical history and takes no medications. Vital signs are within normal limits. Physical examination reveals tenderness to palpation over the anterior ribs bilaterally and 4/5 strength in the proximal hip flexors.

Laboratory studies reveal the following:

Further evaluation shows a fractional excretion of phosphorus of 28% (normal in the setting of hypophosphatemia: <5%). Radiographs of the pelvis demonstrate symmetric, thin, radiolucent lines perpendicular to the cortex of the femoral necks.

Which of the following best describes the underlying paraneoplastic mechanism responsible for this patient's condition, and the most appropriate next step in management to confirm the etiology?

A 38-year-old man comes to the transplant clinic for urgent evaluation due to a 2-day history of decreased urine output, fatigue, and low-grade fever. He underwent a deceased-donor renal transplantation 6 weeks ago for end-stage renal disease secondary to IgA nephropathy. His current medications include tacrolimus, mycophenolate mofetil, and prednisone. Temperature is 37.8°C (100.0°F), blood pressure is 155/95 mmHg, and pulse is 92/min. Physical examination reveals tenderness over the allograft in the right lower quadrant. Laboratory studies show a serum creatinine of 2.9 mg/dL, increased from a baseline of 1.3 mg/dL one week ago. Arrange the following diagnostic and therapeutic steps in the most appropriate chronological sequence for the management of this patient's suspected acute rejection.

An ambulatory clinic evaluates a retired mail carrier reporting a three-month history of tightness and aching in the right calf. The discomfort reliably begins after walking approximately two blocks and fully resolves after five minutes of standing idle. Comorbidities include diet-controlled type 2 diabetes mellitus, hyperlipidemia, and long-standing tobacco use. Bilateral lower extremity pulses are palpable but faintly diminished on the right. Which of the following physical examination findings would most specifically confirm the suspected etiology of this patient's symptoms?

A 24-year-old man comes to the clinic for a routine physical examination required for a new job. He reports feeling well and has no current complaints. However, he mentions that he occasionally notices a mild yellowish tint to his eyes, particularly when he is stressed or fasting for religious holidays. He takes no medications and does not consume alcohol. Vital signs are temperature 37.0°C (98.6°F), blood pressure 118/76 mmHg, pulse 72/min, and respirations 14/min. Physical examination is notable for mild scleral icterus but no abdominal tenderness or hepatosplenomegaly.

Laboratory results are as follows:

A peripheral blood smear shows normal red blood cell morphology.

Based on these laboratory findings, which of the following is the most likely diagnosis?

For each of the following patients presenting with clinical and biochemical evidence of hepatic injury, select the most appropriate confirmatory or highly specific diagnostic laboratory evaluation.

A 54-year-old man with a mechanical mitral valve replacement is maintained on a stable daily dose of warfarin. His international normalized ratio (INR) has been consistently in the therapeutic range of $2.5$ to $3.5$ for the past six months. He presents to the urgent care clinic with a 2-day history of purulent drainage from a leg wound and is prescribed a 7-day course of oral trimethoprim-sulfamethoxazole. Four days later, he comes to the emergency department reporting recurrent epistaxis and large ecchymoses on his trunk. Laboratory evaluation reveals an INR of $7.2$. Which of the following is the most significant pharmacokinetic mechanism responsible for this patient's current laboratory findings?

A 46-year-old woman comes to the oncology clinic to discuss treatment planning. She recently underwent a lumpectomy and sentinel lymph node biopsy for a right-sided breast mass. Surgical pathology confirmed invasive ductal carcinoma. Immunohistochemical staining demonstrates that the tumor is estrogen receptor-negative, progesterone receptor-negative, and strongly positive ($3+$) for a specific transmembrane receptor tyrosine kinase (HER2/neu). The patient is scheduled to begin an adjuvant chemotherapy regimen that includes a targeted monoclonal antibody against this receptor. The targeted receptor pathway is a primary driver of neoplastic proliferation in her tumor, but it is also physiologically essential for cellular survival and stress response in another major organ system. Based on the mechanism of action of the planned targeted therapy, which of the following baseline diagnostic studies is most critical to obtain prior to treatment initiation?

An infectious disease physician is evaluating a 31-year-old male who reports one week of high fevers, drenching night sweats, and a painfully swollen lump on the right side of his neck. Six weeks prior, the patient was diagnosed with advanced HIV infection (CD4+ cell count: 45/mm³) along with disseminated Mycobacterium avium complex (MAC). At that time, a targeted antimicrobial regimen of azithromycin and ethambutol was initiated. Antiretroviral therapy (ART) was subsequently added four weeks ago. The patient initially showed significant clinical improvement, but his symptoms recurred over the past week. Laboratory studies today reveal a CD4+ cell count of 210/mm³ and an undetectable HIV viral load. Fine-needle aspiration of the enlarged right cervical lymph node yields sterile necrotic material, and acid-fast bacilli staining is negative. Which of the following is the most likely underlying immunologic mechanism for this patient's current presentation?

A $32$-year-old woman comes to the primary care clinic reporting a $6$-month history of chronic diarrhea, abdominal bloating, and an unintentional weight loss of $5$ kg ($11$ lbs). She describes her bowel movements as bulky, foul-smelling, and difficult to flush. Her medical history is significant for type $1$ diabetes mellitus, which is managed with an insulin pump. Vital signs are within normal limits. Physical examination reveals a mildly distended abdomen with hyperactive bowel sounds but no tenderness, guarding, or organomegaly. Initial laboratory studies show a hemoglobin of $10.5$ g/dL with a mean corpuscular volume of $74$ fL. Which of the following is the most appropriate next step in diagnostic evaluation?

A 38-year-old woman is evaluated in the outpatient clinic for progressively worsening fatigue, decreased exercise tolerance, and a persistent craving to chew on ice. She mentions that her menstrual periods have been exceptionally heavy over the last six months, often requiring her to change pads every two hours. Her vital signs are stable and within normal limits.

Initial laboratory testing reveals the following results:

Based on the provided laboratory panel, which of the following is the most accurate interpretation of this patient's hematologic status?

A 71-year-old woman with a 50-pack-year smoking history is referred to the oncology clinic after a routine chest radiograph reveals a 3.2-cm spiculated mass in the right upper lobe and a widened right paratracheal stripe. She has a chronic cough but is otherwise asymptomatic. Her performance status is excellent. Arrange the following steps in the most appropriate, evidence-based sequence for the diagnostic workup, clinical staging, and treatment planning of this patient's condition.

A 34-year-old man with a history of intravenous substance use is brought to the emergency department due to a 1-week history of severe chills, intermittent high fevers, and profound fatigue. His temperature is 39.1°C (102.4°F), blood pressure is 112/64 mm Hg, and pulse is 115/min. Cardiac auscultation reveals a prominent holosystolic murmur heard best at the left lower sternal border that significantly increases in intensity during inspiration. Based on the most likely underlying diagnosis, which of the following physical examination findings may also be characteristic of this patient's condition? (Select all that apply)

A 62-year-old woman presents to the clinic for a routine health maintenance examination. She feels well and reports no bone pain, abdominal pain, or urinary symptoms. Her medical history is unremarkable, and she takes no medications. Vital signs are within normal limits.

A comprehensive metabolic panel and subsequent testing reveal the following laboratory results:

Which of the following is the most likely diagnosis?

A 45-year-old man presents to the outpatient clinic for follow-up after his third episode of nephrolithiasis in the past two years. Stone analysis from his most recent episode revealed a pure calcium oxalate composition. He has a history of primary hypertension and obesity. His current medications include amlodipine and various over-the-counter health supplements. He reports drinking 2 to 3 liters of water daily. Which of the following historical elements are MOST important to elicit to identify the underlying risk factors for his recurrent calcium oxalate nephrolithiasis? (Select all that apply)

A 42-year-old woman is evaluated in the intensive care unit for new-onset oozing of blood from her intravenous catheter sites and a widespread petechial rash. She was admitted two days ago for severe sepsis secondary to acute pyelonephritis. Her temperature is 38.8°C (101.8°F), blood pressure is 90/55 mmHg, and pulse is 118/min.

Laboratory studies show:

Peripheral blood smear reveals numerous schistocytes.

Based on the laboratory findings, which of the following is the most likely diagnosis?

Match each clinical and biochemical profile of a patient presenting with a disorder of sex development or steroidogenesis to its precise underlying enzymatic or molecular mechanism.

Emergency medical services bring a 52-year-old man to the emergency department after he was found unresponsive in a park. He has a known history of severe alcohol use disorder. On physical examination, his temperature is $36.5^\circ\text{C}$ ($97.7^\circ\text{F}$), blood pressure is $110/70 \text{ mmHg}$, pulse is $98/\text{min}$, and respiratory rate is $16/\text{min}$. He is uncooperative and confused but moves all extremities spontaneously.

Initial laboratory studies reveal the following:

A toxicology screen is negative for acetaminophen and salicylates. His blood ethanol level is undetectable. The laboratory reports a measured serum osmolality of $324 \text{ mOsm/kg H}_2\text{O}$.

Based on the provided laboratory results, what is the patient's calculated osmolar gap?

A 48-year-old woman is evaluated in the outpatient clinic for persistently elevated blood pressure. She was diagnosed with hypertension six months ago. Her blood pressure today is $168/98 \text{ mmHg}$ despite verified adherence to maximum tolerated doses of amlodipine and valsartan. The patient reports occasional headaches and generalized weakness over the past two months but otherwise feels well. Her past medical history is notable for osteoarthritis and generalized anxiety disorder. Her current medications include amlodipine, valsartan, and acetaminophen as needed. She explicitly denies using nonsteroidal anti-inflammatory drugs. She does not smoke or consume alcohol. BMI is $24 \text{ kg/m}^2$. Physical examination reveals a regular heart rate of $78 \text{ /min}$ and no abdominal bruits, edema, or focal neurologic deficits.

Laboratory studies show:
Serum sodium: $144 \text{ mEq/L}$
Serum potassium: $2.8 \text{ mEq/L}$
Serum chloride: $102 \text{ mEq/L}$
Serum bicarbonate: $30 \text{ mEq/L}$
Serum creatinine: $0.8 \text{ mg/dL}$
Plasma renin activity: Undetectable
Plasma aldosterone concentration: $< 2 \text{ ng/dL}$

Which of the following questions is most appropriate to ask next to determine the underlying etiology of this patient's condition?

A 64-year-old man with a history of advanced non-small cell lung cancer presents to the emergency department reporting two days of worsening shortness of breath, profound generalized weakness, and episodes of near-syncope. He states he feels slightly more comfortable when sitting upright and leaning forward. Vital signs show a temperature of 37.1°C (98.8°F), blood pressure of 86/66 mmHg, heart rate of 124/min and regular, and respiratory rate of 26/min. The patient appears diaphoretic, and his extremities are cool and clammy. Examination of the neck reveals marked distension of the jugular veins up to the angle of the mandible while the patient is sitting at a 45-degree incline. Based on the most likely underlying pathophysiological process causing this patient's acute decompensation, which of the following additional physical examination findings are most likely to be present? (Select all that apply.)