Renal — MCQs

A 32-year-old man is brought to the Emergency Department after 3 consecutive days of diarrhea, fatigue and weakness. His stool has been soft and mucoid, with no blood stains. The patient just came back from a volunteer mission in Guatemala, where he remained asymptomatic. His personal medical history is unremarkable. Today his blood pressure is 98/60 mm Hg, pulse is 110/min, respiratory rate is 19/min, and his body temperature is 36.7°C (98.1°F). On physical exam, he has sunken eyes, dry mucosa, mild diffuse abdominal tenderness, and hyperactive bowel sounds. Initial laboratory tests are shown below: Serum creatinine (SCr) 1.8 mg/dL Blood urea nitrogen (BUN) 50 mg/dL Serum sodium 132 mEq/L Serum potassium 3.5 mEq/L Serum chloride 102 mEq/L Which of the following phenomena would you expect in this patient?

A 22-year-old male college student volunteers for a research study involving renal function. He undergoes several laboratory tests, the results of which are below: Urine Serum Glucose 0 mg/dL 93 mg/dL Inulin 100 mg/dL 1.0 mg/dL Para-aminohippurate (PAH) 150 mg/dL 0.2 mg/dL Hematocrit 50% Urine flow rate 1 mL/min What is the estimated renal blood flow?

A 56-year-old man comes to the emergency department because of a 3-day history of severe epigastric pain that is radiating to his back and accompanied by nausea and vomiting. He has a history of alcohol use disorder. His blood pressure is 90/60 mm Hg and his pulse is 110/min. Physical examination shows diffuse abdominal tenderness and distention. Laboratory studies show: Serum Lipase 180 U/L (N = < 50 U/L) Amylase 150 U/L Creatinine 2.5 mg/dL Urine Sodium 45 mEq/L Osmolality 280 mOsmol/kg H2O Epithelial cell casts numerous Laboratory studies from a recent office visit were within normal limits. This patient's condition is most likely to affect which of the following kidney structures first?

A 55-year-old woman comes to the physician because of a 6-month history of worsening shortness of breath on exertion and fatigue. She has type 1 diabetes mellitus, hypertension, hypercholesterolemia, and chronic kidney disease. Her mother was diagnosed with colon cancer at the age of 65 years. Her blood pressure is 145/92 mm Hg. Examination shows conjunctival pallor. Laboratory studies show: Hemoglobin 9.2 g/dL Mean corpuscular volume 88 μm3 Reticulocyte count 0.6 % Serum Ferritin 145 ng/mL Creatinine 3.1 mg/dL Calcium 8.8 mg/dL A fecal occult blood test is pending. Which of the following is the most likely underlying cause of this patient's symptoms?

A 52-year-old man is brought to the emergency department by ambulance after a motor vehicle accident. He was an unrestrained passenger who was ejected from the vehicle. On presentation, he is found to be actively bleeding from numerous wounds. His blood pressure is 76/42 mmHg and pulse is 152/min. Attempts at resuscitation fail, and he dies 25 minutes later. Autopsy shows blood in the peritoneal cavity, and histology of the kidney reveals swelling of the proximal convoluted tubule epithelial cells. Which of the following is most likely the mechanism underlying the renal cell findings?

A 78-year-old woman is brought by her grandson to the urgent care clinic following a fall. He states that he was in the kitchen making lunch when he heard a thud in the living room. When he ran into the room, he found the patient conscious but lying on the floor. The patient says she remembers getting up to go to the bathroom, feeling lightheaded, and then “blacking out.” She says “it all happened at once,” so she does not remember if she hit her head. The son denies witnessing myoclonic jerks. The patient denies any urinary or bowel incontinence. The patient states that she has had similar episodes like this before but had never fallen or fainted. Her medical history is significant for rheumatoid arthritis and osteoporosis. She takes methotrexate and alendronate. She smokes 1/2 a pack of cigarettes per day. The patient’s temperature is 97°F (36.1°C), blood pressure is 110/62 mmHg, pulse is 68/min, and respirations are 13/min with an oxygen saturation of 98% on room air. She has a 3-cm area of ecchymosis on her right upper extremity that is tender to palpation. Laboratory data, radiography of the right upper extremity, and a computed tomography of the head are pending. Which of the following is most likely true in this patient?

A 22-year-old female presents to your office with gas, abdominal distention, and explosive diarrhea. She normally enjoys eating cheese but has been experiencing these symptoms after eating it for the past few months. She has otherwise been entirely well except for a few days of nausea, diarrhea, and vomiting earlier in the year from which she recovered without treatment. Which of the following laboratory findings would you expect to find during workup of this patient?

A 78-year-old man dies suddenly from complications of acute kidney failure. An autopsy is performed and microscopic evaluation of the kidneys shows pale, swollen cells in the proximal convoluted tubules. Microscopic evaluation of the liver shows similar findings. Which of the following is the most likely underlying mechanism of these findings?

A 28-year-old woman presents to her primary care physician with recurring muscle cramps that have lasted for the last 2 weeks. She mentions that she commonly has these in her legs and back. She also has a constant tingling sensation around her mouth. On physical examination, her vital signs are stable. The Trousseau sign and Chvostek sign are present with exaggerated deep tendon reflexes. A comprehensive blood test reveals the following: Na+ 140 mEq/L K+ 4.5 mEq/L Chloride 100 mEq/L Bicarbonate 24 mEq/L Creatinine 0.9 mg/dL Ca2+ 7.0 mg/dL Which of the following electrophysiologic mechanisms best explain this woman’s clinical features?

Following passage of a calcium oxalate stone, a 55-year-old male visits his physician to learn about nephrolithiasis prevention. Which of the following changes affecting urine composition within the bladder are most likely to protect against crystal precipitation?