Tüm alıştırma soruları

A 55-year-old man with a history of poorly controlled type 2 diabetes mellitus presents to the emergency department with 4 days of worsening lower back pain. He initially attributed the discomfort to lifting a heavy box at work, but the pain has become progressively severe, is unremitting even at rest, and occasionally awakens him from sleep. His temperature is 37.8°C (100.0°F), blood pressure is 135/85 mmHg, and heart rate is 92/min. The physician is evaluating whether an immediate MRI of the lumbar spine is indicated. Which of the following physical examination findings represent 'red flags' that would specifically dictate the need for urgent spinal imaging to evaluate for severe neurologic compromise or deep space infection? (Select the correct options)

While picnicking at a local park, a 28-year-old man sustains multiple bee stings and rapidly develops a diffuse urticarial rash, lip swelling, and severe shortness of breath. Paramedics transport him to the emergency department. Upon arrival, he is in profound respiratory distress with audible stridor. Vital signs show a heart rate of 135/min, blood pressure of 75/40 mm Hg, and oxygen saturation of 89% on room air. Lung auscultation reveals diffuse expiratory wheezing. A severe type I immunoglobulin E (IgE)-mediated hypersensitivity reaction is recognized.

Arrange the following therapeutic interventions in the most appropriate chronological sequence for the step-wise management of this patient's systemic immunologic reaction.

A 21-year-old man is brought to the emergency department by campus security due to severe agitation, confusion, and visual hallucinations. His friends report he ingested an unknown pill at a music festival three hours ago. Vital signs show a temperature of 38.9°C (102.0°F), blood pressure of 165/95 mmHg, heart rate of 132/min, and respiratory rate of 20/min. The attending physician is attempting to differentiate between a sympathomimetic toxidrome (e.g., cocaine, amphetamines) and an anticholinergic toxidrome (e.g., diphenhydramine, Jimson weed) based solely on the physical examination.

Which of the following physical examination findings would specifically establish a diagnosis of anticholinergic toxicity rather than sympathomimetic toxicity in this patient? (Select all that apply)

A $38$-year-old male is evaluated in the ambulatory clinic for newly discovered hypertension. During a health screening two weeks ago, his blood pressure was recorded at $162/100$ mmHg. Today, his vitals show a blood pressure of $158/98$ mmHg with a regular pulse of $76$/min. The patient takes no daily medications and has no family history of early-onset cardiovascular disease. He mentions experiencing intermittent muscle cramps and generalized weakness over the past few months. Physical examination is unremarkable, with no abdominal bruits, abnormal facies, or purple striae. Initial basic metabolic panel results demonstrate a serum sodium of $144$ mEq/L and a serum potassium of $2.9$ mEq/L. Which of the following is the most appropriate next step in laboratory evaluation?

A 28-year-old man is brought to the emergency department due to a 2-hour history of progressive swelling of his face, lips, and tongue, along with severe, crampy abdominal pain and nausea. He denies any recent changes in diet, insect stings, or new environmental exposures. He has no itching or skin rash. His temperature is 37.1 C (98.8 F), blood pressure is 110/70 mm Hg, pulse is 92/min, and respirations are 18/min. Physical examination shows pronounced, nonpitting edema of the lips and tongue, but no urticaria. Bowel sounds are hyperactive. The patient states that a similar, milder episode occurred when he was 15 years old following a tooth extraction. He takes no daily medications and has no known allergies. Initial treatment with intramuscular epinephrine, intravenous diphenhydramine, and corticosteroids is administered, but his condition remains unchanged 45 minutes later. Laboratory studies reveal a significantly decreased serum C4 level and a normal C3 level. Which of the following is the most likely primary mechanism mediating this patient's current symptoms?

An infectious disease specialist is consulting on a 48-year-old male inpatient with a severe systemic infection. The patient's body mass is $75 \text{ kg}$. The physician decides to start a continuous intravenous infusion of a narrow-therapeutic-index antibiotic. The established target steady-state serum concentration is $15 \text{ mg/L}$. Pharmacokinetic data for this drug indicate a volume of distribution of $0.8 \text{ L/kg}$ and an elimination half-life of $13.86 \text{ hours}$. Assuming first-order elimination kinetics, what maintenance infusion rate (in $\text{mg/hr}$) is required to sustain the target concentration?

A 42-year-old woman is evaluated in the outpatient clinic for a 6-month history of progressive weight gain, easy bruising, and proximal muscle weakness. Physical examination reveals central adiposity, facial plethora, wide purple striae on her abdomen, and trace lower extremity edema. Her blood pressure is 155/95 mmHg. She takes no medications and denies the use of exogenous glucocorticoids or over-the-counter supplements. The physician suspects an endogenous endocrine disorder and plans a comprehensive diagnostic workup.

Arrange the following diagnostic laboratory tests and procedures in the most appropriate sequential order to establish the definitive diagnosis and etiology for this patient, starting with the initial diagnostic screening step.

A 35-year-old man comes to the emergency department due to a 24-hour history of high fever, severe headache, photophobia, and nausea. Two months ago, he was evaluated for severe fatigue, episodic dark morning urine, and a recent hepatic vein thrombosis. At that time, flow cytometry of his peripheral blood demonstrated an absence of glycosylphosphatidylinositol (GPI)-anchored proteins, specifically CD55 and CD59, on the surface of his erythrocytes. He was subsequently started on a targeted monoclonal antibody therapy. Today, his temperature is $39.4^\circ\text{C}$ ($102.9^\circ\text{F}$), blood pressure is $90/60\text{ mm Hg}$, and pulse is $122/\text{min}$. Physical examination reveals marked nuchal rigidity and a purpuric rash on the lower extremities. Cerebrospinal fluid analysis reveals a markedly elevated leukocyte count with a neutrophilic predominance, and Gram stain demonstrates intracellular Gram-negative diplococci. Which of the following best describes the immunologic mechanism of the patient's pharmacotherapy that directly led to his current presentation?

An internal medicine physician is called to evaluate a 68-year-old hospitalized patient for new-onset confusion. The patient was admitted two days prior for community-acquired pneumonia and is currently receiving intravenous ceftriaxone and azithromycin. Vital signs remain within normal limits. On physical examination, mucous membranes are moist, skin turgor is normal, and there is no jugular venous distention or peripheral edema. A routine morning basic metabolic panel reveals a serum sodium concentration of $121 \text{ mEq/L}$, a significant decrease from his admission baseline of $134 \text{ mEq/L}$. Arrange the following laboratory tests in the most appropriate sequential order to systematically determine the underlying etiology of this patient's hyponatremia.

A young adult male is brought to the emergency department following an off-road motorcycle collision that resulted in a highly contaminated open fracture of the right tibia. He undergoes prompt surgical debridement and receives tetanus prophylaxis along with empiric broad-spectrum antibiotics. Approximately 36 hours post-operation, he develops excruciating pain at the surgical site that is out of proportion to the visible signs of inflammation. Examination of the leg reveals marked edema, a bronze-colored cutaneous discoloration, and palpable crepitus in the surrounding tissues. Gram stain of a serosanguineous exudate from the wound demonstrates large Gram-positive bacilli with blunt ends and a notable absence of polymorphonuclear leukocytes. Which of the following best describes the molecular mechanism of the primary virulence factor responsible for this patient's rapidly progressive tissue destruction?

A $56$-year-old woman presents to the clinic with a $7$-month history of progressive fatigue, episodic facial flushing, and chronic watery diarrhea. She also reports bilateral leg swelling that has worsened over the past few weeks. Her medical history is unremarkable, and she takes no medications. Vital signs show a temperature of $37.1^{\circ}\text{C}$ ($98.8^{\circ}\text{F}$), pulse of $92\text{/min}$, blood pressure of $115/70\text{ mmHg}$, and respirations of $16\text{/min}$. On physical examination, blanching telangiectasias are noted on her face and neck. Jugular venous distention is present. The abdomen is soft, but a firm, irregular liver edge is palpated $5\text{ cm}$ below the right costal margin. Cardiac auscultation reveals a prominent right ventricular heave and a grade $3/6$ holosystolic murmur best heard at the left lower sternal border. Which of the following dynamic physical examination findings is most likely to be present in this patient?

A 54-year-old male construction worker visits his primary care provider complaining of a 6-month history of progressive fatigue, generalized weakness, and joint pain affecting his hands, wrists, and knees. He also mentions a recent, uncharacteristic decline in libido. His medical history is notable for type 2 diabetes mellitus diagnosed one year ago, which is currently managed with metformin. Vital signs are within normal limits. Physical examination reveals a firm, palpable liver edge 4 cm below the right costal margin and a diffuse, bronze-colored hyperpigmentation of the skin that is most prominent on his face and forearms. Joint examination demonstrates bony enlargement of the second and third metacarpophalangeal joints bilaterally without significant warmth, erythema, or synovial thickening. Which of the following is the most appropriate next step in laboratory evaluation?

A 45-year-old man is hospitalized for the treatment of relapsed diffuse large B-cell lymphoma. Three days ago, he received an infusion of anti-CD19 chimeric antigen receptor (CAR) T cells. He now acutely develops a temperature of 39.8°C (103.6°F), a heart rate of 125/min, and blood pressure of 82/45 mm Hg that is unresponsive to a 2-liter intravenous fluid bolus. Oxygen saturation is 93% on room air. Laboratory evaluation reveals profoundly elevated serum ferritin, C-reactive protein, and lactate dehydrogenase. The patient is diagnosed with a severe immunologic complication related to his recent cellular therapy. Which of the following is the most appropriate targeted intervention for this patient's current condition?

A 27-year-old man establishes care for evaluation of resting tachycardia and occasional palpitations. He feels otherwise well and has no weight changes, heat intolerance, or visual disturbances. His pulse is 108/min and blood pressure is 138/82 mmHg. Physical examination reveals a normal-sized, non-tender thyroid gland and a fine resting tremor. There is no proptosis or pretibial myxedema. Laboratory studies show:

A recent magnetic resonance imaging (MRI) of the brain, ordered by his previous provider, showed a normal pituitary gland and sella turcica. Serum alpha-subunit levels are within normal limits. Which of the following describes the fundamental molecular mechanism underlying this patient's laboratory abnormalities?

A 27-year-old woman is brought to the emergency department by her partner due to severe, diffuse abdominal pain and new-onset confusion that began 24 hours ago. The pain is severe, constant, and associated with nausea and non-bilious vomiting. Three days ago, she was evaluated at an urgent care center for a presumed urinary tract infection and was prescribed oral trimethoprim-sulfamethoxazole. She has no other medical history and does not use tobacco, alcohol, or illicit drugs.

Temperature is 37.1°C (98.8°F), blood pressure is 165/100 mmHg, pulse is 118/min, and respirations are 18/min. Physical examination shows an anxious and profusely diaphoretic woman. The abdomen is soft and non-distended with diffuse mild discomfort on deep palpation, but there is no localized tenderness, guarding, or rebound. Bowel sounds are diminished. Neurologic examination reveals symmetric 4/5 weakness in the proximal upper and lower extremities and decreased deep tendon reflexes.

Laboratory studies show:

Serum $\beta$-hCG is negative. A non-contrast CT scan of the head shows no abnormalities.

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

Match the following distinct neurological physical examination findings with the corresponding clinical condition or anatomic lesion.

Evaluate the following distinct patient encounters. For each clinical presentation, select the most appropriate targeted laboratory testing panel to establish the diagnosis.

A 48-year-old man presents to the transplant clinic with a 2-day history of decreased urine output, malaise, and mild right lower quadrant pain. He underwent a deceased-donor kidney transplantation 4 months ago for end-stage renal disease secondary to IgA nephropathy. His maintenance immunosuppressive regimen includes tacrolimus, mycophenolate mofetil, and low-dose prednisone. Vital signs show a temperature of 37.8°C (100°F) and blood pressure of 152/94 mm Hg. Physical examination reveals tenderness over the allograft in the right lower quadrant. Laboratory studies demonstrate a serum creatinine of 3.4 mg/dL, representing an acute increase from his baseline of 1.4 mg/dL obtained two weeks ago. Urinalysis shows 1+ protein and no white blood cells.

Arrange the following steps in the most appropriate chronological order for the evaluation and management of this patient's acute allograft dysfunction.

A 58-year-old man with type 2 diabetes mellitus and heart failure with reduced ejection fraction presents to the emergency department with nausea, diffuse abdominal pain, and profound fatigue for the past 24 hours. Two days ago, he underwent a colonoscopy, for which he completed a standard bowel preparation and fasted. His medications include metformin, lisinopril, carvedilol, and a medication that was added one month ago for his heart failure. On physical examination, his blood pressure is 105/65 mm Hg, pulse is 112/min, and respirations are 24/min and deep. Mucous membranes are dry.

Laboratory results:

Which of the following best describes the primary biochemical mechanism responsible for this patient's acid-base disturbance?

A 62-year-old woman is evaluated for right upper quadrant abdominal pain and unintentional weight loss. Imaging reveals a 4-cm irregular breast mass and multiple hepatic lesions consistent with metastasis. Biopsy of the breast mass confirms invasive ductal carcinoma. The development of these distant hepatic metastases involves a complex, multi-step cascade of cellular and molecular changes. Arrange the following pathophysiologic steps of the metastatic cascade in the correct chronological sequence, beginning with the initial alteration in the primary breast tumor cells and ending with the establishment of the secondary hepatic tumor.