Tüm alıştırma soruları

A 54-year-old woman presents to the clinic with a chronic, productive cough that is particularly worse in the mornings. She has a 35-pack-year smoking history and no other significant medical history. Physical examination reveals scattered rhonchi that clear with coughing. Pulmonary function testing demonstrates an FEV1/FVC ratio of 65%. Given her significant smoking history and a recent mild episode of hemoptysis, a bronchoscopy is performed. Histological examination of a bronchial mucosal biopsy reveals the replacement of the normal ciliated pseudostratified columnar epithelium by stratified squamous epithelium. There is no evidence of cellular atypia or invasion. Which of the following is the most likely cellular mechanism underlying this histologic change?

A 27-year-old woman is admitted to the hospital with acute-onset left leg pain and swelling. Compression ultrasonography reveals an acute proximal deep venous thrombosis in the left popliteal and femoral veins. She has no significant past medical history, takes no medications, and has no recent surgeries or periods of immobilization. Her mother experienced a pulmonary embolism at age 40. The patient is immediately started on a therapeutic low-molecular-weight heparin bridge to warfarin. Given the unprovoked nature of the deep venous thrombosis and her family history, an evaluation for inherited thrombophilia is planned by the primary team. Which of the following is the most appropriate approach to ordering laboratory tests for this patient's hypercoagulability evaluation?

Match the following Hepatitis B serologic laboratory panels with their most accurate corresponding clinical status.

An infectious disease specialist is preparing a grand rounds presentation on the diverse strategies that human pathogens use to evade the host immune system and establish productive infections. The presentation highlights several distinct mechanisms, including the subversion of cellular peptide transport, the secretion of immunomodulatory analogs, escaping intracellular degradation, and the constant alteration of surface antigens. Match the following pathogens to their corresponding primary molecular mechanism of immune evasion or intracellular survival.

During the cardiovascular physical examination, specific eponymous signs and pulse contour abnormalities can provide critical diagnostic clues about underlying hemodynamics and cardiac pathology. Match each described cardiovascular physical examination finding with its primary underlying pathophysiological mechanism.

Match each complex patient clinical presentation with the most appropriate, highly specific initial or confirmatory diagnostic laboratory test to establish the diagnosis.

An occupational health physician evaluates a 48-year-old male construction worker for standard job clearance. The patient mentions that over the past two years, he has had to resize his wedding band twice and purchase larger work boots. He also reports increased daytime somnolence and frequent, dull headaches. Physical examination is notable for a prominent jawline, enlarged hands with thick fingers, and widening spaces between his lower teeth. Vital signs show a blood pressure of 142/90 mm Hg and a heart rate of 76/min. Which of the following is the most appropriate next step in laboratory evaluation?

A 74-year-old man is brought to the emergency department by his daughter due to a 1-day history of passing dark, tarry stools, accompanied by severe lightheadedness and profound fatigue. His medical history is significant for nonvalvular atrial fibrillation, essential hypertension, and benign prostatic hyperplasia. His home medications include apixaban 5 mg twice daily, lisinopril, and tamsulosin.

Three days ago, the patient was evaluated at an urgent care clinic for a severe cough and fever; he was diagnosed with a presumed atypical respiratory infection and prescribed a 5-day course of clarithromycin. The daughter also notes that the patient began taking a daily over-the-counter Ginkgo biloba extract two weeks ago to "help with his memory."

On physical examination, the patient appears pale and diaphoretic. His temperature is 37.1°C (98.8°F), blood pressure is 88/54 mm Hg, and heart rate is 118/min. Digital rectal examination reveals gross melena.

Laboratory studies obtained on admission:
Hemoglobin: 7.2 g/dL (baseline 13.8 g/dL one month ago)
Platelet count: 185,000/mm³
Serum creatinine: 1.2 mg/dL (baseline 1.1 mg/dL)
Weight: 82 kg (180 lbs)

Based on the evaluation of this patient's medical and pharmacological history, which of the following elements represent the primary precipitating factors for his acute hemorrhagic presentation? (Select all that apply)

Match the following clinically significant drug combinations with the primary pharmacokinetic or pharmacodynamic mechanism underlying their interaction.

A $39$-year-old male presents to the internal medicine clinic for management of elevated blood pressure. He was diagnosed with hypertension six months ago and is currently prescribed maximal tolerated doses of amlodipine and benazepril. He reports consistent adherence to his medications. Over the past few weeks, he has experienced occasional muscle spasms in his lower extremities and mild generalized weakness. He does not take any over-the-counter medications, supplements, or illicit drugs. Blood pressure is $158/98$ mmHg, and heart rate is $74$/min. Physical examination reveals a normal body habitus with no abdominal bruits, striae, or abnormal fat distribution. Laboratory testing shows a serum potassium level of $3.1$ mEq/L and a serum creatinine of $0.9$ mg/dL. The patient has never been prescribed diuretic therapy. Based on the clinical presentation, which of the following diagnostic studies should be prioritized as the initial step to establish the underlying diagnosis?

During the evaluation of patients with suspected severe cardiovascular pathology, astute bedside physical examination can often differentiate between underlying etiologies. Match the following advanced eponymous physical examination findings with the specific pathophysiologic mechanism that produces them.

A 45-year-old man presents to the clinic complaining of a severe headache, tremors, and decreased urine output over the past two days. His medical history is significant for a deceased-donor renal transplant two years ago for IgA nephropathy. His daily medications include tacrolimus, mycophenolate mofetil, and prednisone. Eight days ago, he was evaluated at an urgent care center for a respiratory tract infection and was prescribed a 7-day course of clarithromycin. Today, his blood pressure is 165/95 mmHg, compared to 120/75 mmHg at his last visit. Laboratory studies show a serum creatinine of 2.2 mg/dL, elevated from his baseline of 1.1 mg/dL. Which of the following pharmacokinetic alterations regarding the patient's immunosuppressive regimen most likely occurred?

Match each clinical presentation with the corresponding underlying mechanism of cellular injury and tissue necrosis.

A 68-year-old man undergoes a surveillance colonoscopy following a previous history of low-risk tubular adenomas. During the procedure, a $2.2$ cm pedunculated polyp is identified in the descending colon and removed en bloc via snare polypectomy. The patient is discharged without immediate complications. Three days later, the pathology report confirms a tubular adenoma harboring a focus of invasive adenocarcinoma. The carcinoma invades through the muscularis mucosae and extends into the submucosa of the polyp stalk. The multidisciplinary tumor board is convened to discuss whether the endoscopic polypectomy was definitive or if a formal left hemicolectomy is strictly indicated. Which of the following histopathologic features from the synoptic report would independently mandate a formal surgical resection? (Select all that apply)

A 59-year-old male is brought to the emergency department after a sudden syncopal episode at an airport following a 14-hour flight. Upon arrival, he is conscious but severely dyspneic. Vital signs include a blood pressure of 72/45 mmHg, heart rate of 138/min, respiratory rate of 32/min, and SpO2 of 81% on room air. Physical examination reveals prominent jugular venous distension, clear lungs to auscultation, and a right ventricular heave. An electrocardiogram shows sinus tachycardia and an S1Q3T3 pattern. The clinical picture is highly suggestive of a massive pulmonary embolism causing obstructive shock. Arrange the following management and diagnostic steps in the most appropriate sequential order for this patient.

A 68-year-old man is brought to the emergency department by his family due to worsening confusion, lethargy, and mild nausea over the past three days. He has no history of heart failure, cirrhosis, or kidney disease. His vital signs are within normal limits, and he is orthostatically stable with moist mucous membranes. Initial laboratory testing reveals a severe hyponatremia with a serum sodium level of 118 mEq/L.

Arrange the following laboratory tests in the most appropriate sequential order to logically establish the etiology of this patient's hyponatremia.

A 54-year-old female presents to an outpatient nephrology clinic for rapid-onset swelling in her lower extremities and dark urine. She also reports progressive joint stiffness in her hands and knees over the past month, accompanied by a new, non-itchy rash on her shins. Her past medical history is significant for a brief period of intravenous drug use in her early twenties, but she has not sought medical care in over a decade. Her vital signs include a blood pressure of 152/94 mmHg. Physical examination demonstrates 2+ pitting edema to the knees and scattered, palpable purpuric lesions across both lower legs.

Laboratory testing reveals:
Serum creatinine: 1.9 mg/dL (Baseline unknown)
Urinalysis: 3+ protein, 20-30 red blood cells/hpf, dysmorphic red cells present
Rheumatoid factor: 420 IU/mL (Normal: < 15 IU/mL)
Complement C3: 92 mg/dL (Normal: 80-160 mg/dL)
Complement C4: 6 mg/dL (Normal: 15-45 mg/dL)
Hepatitis C virus RNA: 2.1 x 10^6 IU/mL

Which of the following best describes the fundamental immunopathologic mechanism driving this patient's current presentation?

A 29-year-old nulliparous woman is evaluated in the outpatient clinic for preconception counseling. Her medical history is significant for an unprovoked deep venous thrombosis in her right lower extremity three years ago, which was treated with a 6-month course of oral anticoagulation. She has no history of spontaneous bruising, epistaxis, or prolonged bleeding following minor injuries or dental procedures. Her physical examination is unremarkable. Laboratory studies obtained as part of her preconception workup reveal a normal prothrombin time (PT) and a platelet count of 210,000/mm³. However, her activated partial thromboplastin time (aPTT) is 58 seconds (normal: 25-40 seconds). An immediate 1:1 mixing study with normal pooled plasma fails to correct the aPTT into the normal reference range. Which of the following best describes the pathophysiologic mechanism responsible for this patient's abnormal coagulation assay?

A 28-year-old woman is evaluated prior to an elective cholecystectomy. She has no history of abnormal bleeding, and her physical examination is unremarkable. Routine preoperative laboratory testing reveals the following:

A mixing study is performed, and the addition of normal plasma fails to correct the patient's aPTT to within the reference range. Which of the following is the most likely explanation for these laboratory findings?

A 4-year-old boy is brought to the emergency department with a 3-day history of severe, crampy abdominal pain and grossly bloody diarrhea. His parents report that he attended a neighborhood cookout one week ago where he consumed a hamburger. Initial laboratory studies reveal severe thrombocytopenia, microangiopathic hemolytic anemia with schistocytes on peripheral smear, and an elevated serum creatinine level. The child's condition is caused by a bacterial exotoxin. Arrange the following steps in the precise molecular pathogenesis of this toxin in sequential chronological order, from initial host cell interaction to final cellular consequence.