A
B
C
D
100
An 18-year-old man is evaluated in the emergency department for a severe asthma exacerbation unresponsive to intensification of his home program of albuterol and fluticasone-salmeterol inhalers. Intravenous magnesium sulfate, prednisone, and inhaled albuterol are initiated.
On physical examination, the patient is in respiratory distress. Blood pressure is 145/88 mm Hg, respiratory rate is 32/min, pulse is 108/min, and oxygen saturation is 95% with the patient breathing ambient air. Pulmonary examination reveals diffuse wheezes. The remainder of the examination is unremarkable.
Laboratory studies:
Electrolytes :
Sodium 140 mEq/L (140 mmol/L)
Potassium 3.2 mEq/L (3.2 mmol/L)
Chloride 110 mEq/L (110 mmol/L)
Bicarbonate 24 mEq/L (24 mmol/L)
Glucose 124 mg/dL (6.9 mmol/L)
What is the most likely cause of this patient's hypokalemia?
Albuterol
Hyperglycemia
Hypermagnesemia
Prednisone
100
A 69-year-old woman is evaluated for a 2-month history of worsening fatigue, weight loss, and anorexia. She has no other medical problems and takes no medications.
On physical examination, the patient is afebrile. Blood pressure is 160/95 mm Hg, pulse rate is 88/min, respiration rate is 16/min, and oxygen saturation is 100% breathing ambient air. The remainder of the examination is unremarkable.
Laboratory studies:
Hematocrit 25.5%
Albumin 3.7 g/dL (37 g/L)
Calcium 10.9 mg/dL (2.7 mmol/L)
Creatinine 4.2 mg/dL (371.3 µmol/L)
Free κ light chains Elevated
Free λ light chains Elevated
κ/λ Free light chain ratio 4.1 (normal, 0.26-1.65)
Urinalysis No blood; 1+ protein
Urine protein-creatinine ratio 2500 mg/g
Urine output 2.3 L/24 h
Kidney biopsy confirms the presence of myeloma cast nephropathy.
What is the most appropriate management?
Chemotherapy
Hemodialysis
Hospice referral
Plasmapheresis
100
A 34-year-old woman is evaluated for hypertension. During the past 3 months, two blood pressure measurements in health care settings averaged 150/90 mm Hg. During the same time period, three blood pressure measurements obtained outside of health care settings averaged 128/78 mm Hg. She has no other pertinent personal or family history. She takes no medications.
On physical examination, blood pressure is 144/92 mm Hg in both arms, pulse rate is 80/min, and respiration rate is 18/min. BMI is 22. The remainder of the examination is normal.
What is the most appropriate management?
Perform ambulatory blood pressure monitoring
Begin chlorthalidone
Obtain renal artery imaging
Recheck blood pressure in the office in 3 months
100
A 25-year-old woman is evaluated for a 6-month history of fatigue, joint pain, sun sensitivity, and pleuritic chest pain. Medications are an oral contraceptive pill and as-needed naproxen.
On physical examination, temperature is 38.2 °C (100.8 °F), blood pressure is 142/90 mm Hg, and pulse rate is 100/min. The fingers and wrist joints are tender, but there is no synovitis. The remainder of the examination is normal.
Laboratory studies show a serum creatinine level of 1.4 mg/dL (123.8 µmol/L); dipstick urinalysis shows 2+ blood, 3+ protein, positive leukocyte esterase, and no nitrites.
Urine microscopy is shown.
What is the most appropriate diagnostic test?
Kidney biopsy
Kidney ultrasonography
Urine culture
Cystoscopy
200
A 63-year-old woman is hospitalized for cardiac catheterization for unstable angina. History is significant for stage G3 chronic kidney disease attributed to diabetic nephropathy. Medications are heparin, metoprolol, losartan, amlodipine, atorvastatin, basal insulin, and prandial insulin.
On physical examination, vital signs are normal. There is no jugular venous distension or lower extremity edema. The remainder of the examination is unremarkable.
Laboratory studies show a serum creatinine level of 2.4 mg/dL (212.2 µmol/L) and an estimated glomerular filtration rate of 24 mL/min/1.73 m2.
What is the most appropriate periprocedure measure to prevent acute kidney injury?
Intravenous 0.9% saline, pre- and postprocedure
Hemodialysis, postprocedure
Intravenous isotonic bicarbonate, pre- and postprocedure
Oral N-acetylcysteine, preprocedure
200
A 52-year-old man is evaluated during a follow-up visit for membranous nephropathy diagnosed by kidney biopsy 1 month ago. His medical history is otherwise unremarkable. Medications are lisinopril, furosemide, and atorvastatin.
On physical examination, vital signs are normal. There is symmetric 2+ pitting edema of the lower extremities. The remainder of the examination is unremarkable.
Laboratory studies:
Albumin 2.1 g/dL (21 g/L)
Total cholesterol 359 mg/dL (9.3 mmol/L)
Creatinine 0.8 mg/dL (70.7 µmol/L)
Urine protein-creatinine ratio 5500 mg/g
What is the most likely complication to develop in this patient during the next 12 months?
Venous thromboembolism
Diabetes mellitus
End-stage kidney disease
Pulmonary hemorrhage
200
A 68-year-old man is evaluated in the emergency department for generalized weakness that began 12 hours ago after ingesting a bottle of magnesium citrate for constipation. He has hypertension, hyperlipidemia, and stage G4 chronic kidney disease. Medications are furosemide, nifedipine, and simvastatin.
On physical examination, blood pressure is 102/64 mm Hg, and pulse rate is 50/min; other vital signs are normal. Muscle strength is 4/5 diffusely. Reflexes are absent throughout. The remainder of the examination is normal.
Laboratory studies:
Calcium 8.4 mg/dL (2.1 mmol/L)
Creatinine 5.5 mg/dL (486.2 µmol/L)
Magnesium 6.8 mg/dL (2.8 mmol/L)
Phosphorus 5.5 mg/dL (1.8 mmol/L)
What is the most appropriate immediate treatment?
Intravenous calcium gluconate
Intravenous furosemide
Intravenous sodium bicarbonate
Oral patiromer
200
A 35-year-old man is evaluated during a follow-up visit for an elevated serum creatinine level. The elevated serum creatinine was discovered during a recent hospitalization for cellulitis of the right lower leg that was treated with intravenous cephazolin followed by oral cephalexin for a total of 7 days of antibiotic therapy. He is a migratory agricultural worker. He works in the northeastern United States during summer months and returns to Guatemala for the remainder of the year performing similar work. The patient has no other medical problems and takes no medications.
On physical examination, blood pressure is 138/90 mm Hg; other vital signs are normal. BMI is 27. The remainder of the examination is normal.
Laboratory studies:
Creatinine 2.0 mg/dL (176.8 µmol/L)
Sodium 140 mEq/L (140 mmol/L)
Potassium 5.0 mEq/L (5.0 mmol/L)
Chloride 112 mEq/L (112 mmol/L)
Bicarbonate 18 mEq/L (18 mmol/L)
Urinalysis
Specific gravity 1.015; pH 6.5; no blood; 1+ protein; 1+ leukocytes; 2-5 leukocytes/hpf; 0-2 erythrocytes/hpf; no casts
Urine protein-creatinine ratio
400 mg/g
Kidney ultrasound shows a 9.9-cm right kidney and a 10.3-cm left kidney with increased cortical echogenicity and mild thinning; there is no hydronephrosis.
What is the most likely diagnosis?
Chronic interstitial nephritis
Acute interstitial nephritis
Acute tubular necrosis
IgA nephropathy
Infection-related glomerulonephritis
300
A 69-year-old man is evaluated for a 4-week history of lower extremity edema. He has a 45-pack-year history of smoking but quit 3 years ago. A screening colonoscopy performed 1 year ago was normal. He has no other medical history and takes no medications.
On physical examination, vital signs are normal. There is 2-mm pitting edema of the lower extremities through the ankles, equal on both sides. The remainder of the examination is unremarkable.
Laboratory studies:
Albumin 2.9 g/dL (29 g/L)
Total cholesterol 311 mg/dL (8.1 mmol/L)
Creatinine 1.0 mg/dL (88.4 µmol/L)
24-Hour urine protein excretion 6300 mg/24 h
Kidney biopsy shows membranous nephropathy with negative staining for the phospholipase A2 receptor antigen.
What is the most appropriate test to perform next?
Noncontrast CT of the chest
Kidney and renal vein Doppler ultrasonography
Lower extremity Doppler ultrasonography
Random (spot) urine protein-creatinine ratio
300
A 63-year-old man is evaluated during a follow-up visit for gastroesophageal reflux disease and heartburn. His symptoms are worse after large meals and when lying down and have significantly decreased the quality of his life and disrupted his sleep. He also has stage G4 chronic kidney disease, obesity, and hypertension. Medications are atenolol, lisinopril, and nifedipine.
On physical examination, vital signs are normal. BMI is 38. The remainder of the examination is normal.
Laboratory studies show an estimated glomerular filtration rate of 29 mL/min/1.73 m2.
Weight loss and other lifestyle management modifications for gastroesophageal reflux disease are discussed.
What is the most appropriate additional therapy?
Famotidine
Omeprazole
Oral calcium carbonate and magnesium hydroxide
Sucralfate
300
A 77-year-old woman is evaluated in the ICU for acute kidney injury after being hospitalized 2 days ago for septic shock and acute respiratory distress syndrome secondary to community-acquired pneumonia. She was intubated and vasopressor support was initiated. Over the first 18 hours of hospitalization, she received 3600 mL of Ringer's lactate solution. Current medications are norepinephrine, ceftaroline, levofloxacin, and dexmedetomidine.
On physical examination, the patient is mechanically ventilated. Temperature is 38.4 °C (101.1 °F), blood pressure is 88/52 mm Hg, pulse rate is 105/min, respiration rate is 16/min, and oxygen saturation is 90% with the patient breathing 50% FIO2. Diffusely coarse breath sounds are heard on pulmonary examination. A central venous catheter is in place; central venous pressure measurement is 14 mm Hg.
Urine output is 30 mL/h and unresponsive to escalating doses of intravenous furosemide.
Current laboratory studies:
Creatinine 3.4 mg/dL (300.6 µmol/L)
Sodium 134 mEq/L (134 mmol/L)
Potassium 6.4 mEq/L (6.4 mmol/L)
Chloride 100 mEq/L (100 mmol/L)
Bicarbonate 12 mEq/L (12 mmol/L)
Chest radiograph shows diffuse bilateral infiltrates and vascular cephalization.
What is the most appropriate therapy?
Begin continuous renal replacement therapy
Begin peritoneal dialysis
Continue current management
Switch to intravenous bumetanide
300
A 48-year-old woman is evaluated in the ICU for increasing serum creatinine and oliguria; she has cirrhosis. She was hospitalized 24 hours ago and treated for a bleeding esophageal varix. Outpatient medications are furosemide, spironolactone, nadolol, and norfloxacin. On admission, her serum creatinine level was 1.5 mg/dL (132.6 µmol/L).
On physical examination, blood pressure is 102/63 mm Hg, and pulse rate is 66/min; other vital signs are normal. Ascites and jaundice are present. The remainder of the examination is normal.
Urine output is 190 mL over the past 24 hours.
Current laboratory studies:
Albumin 2.3 g/dL (23 g/L)
Creatinine 2.3 mg/dL (203.3 µmol/L)
Sodium 126 mEq/L (126 mmol/L)
Potassium 3.9 mEq/L (3.9 mmol/L)
Chloride 95 mEq/L (95 mmol/L)
Bicarbonate 18 mEq/L (18 mmol/L)
Urine sodium <10 mEq/L (10 mmol/L)
Urinalysis
Specific gravity 1.030; pH 5.0; trace protein; 2+ bilirubin; bilirubin staining; no erythrocytes or leukocytes
Kidney ultrasound shows normal-appearing kidneys without hydronephrosis.
Diuretics are withheld, and norepinephrine infusion is initiated.
What is the most appropriate additional treatment?
Intravenous albumin
Hemodialysis
Oral midodrine and intravenous octreotide
Transjugular intrahepatic portosystemic shunt
400
A 54-year-old woman is evaluated during a follow-up visit after beginning lisinopril for hypertension 2 weeks ago. History is also significant for chronic kidney disease. Her only other medication is amlodipine.
On physical examination, blood pressure is 128/78 mm Hg; other vital signs are normal. There is 1+ pitting pretibial edema bilaterally. The remainder of the examination is unremarkable.
Laboratory studies:
Creatinine 1.7 mg/dL (150.3 µmol/L); 2 weeks ago: 1.2 mg/dL (106.1 µmol/L)
Potassium 5.7 mEq/L (5.7 mmol/L); 2 weeks ago: 4.4 mEq/L (4.4 mmol/L)
Estimated glomerular filtration rate 33 mL/min/1.73 m2; 2 weeks ago, 50 mL/min/1.73 m2
Two weeks ago, laboratory studies showed a urine albumin-creatinine ratio of 1600 mg/g.
What is the most appropriate management?
Discontinue lisinopril; add furosemide
Continue lisinopril; add furosemide
Continue lisinopril; recheck laboratory studies in 2 weeks
Discontinue lisinopril; add losartan
400
A 38-year-old woman is evaluated in the emergency department for a 4-hour history of left flank pain that radiates to the groin. She is otherwise well and takes no medications.
A noncontrast helical CT scan of the abdomen shows an 11-mm stone in the proximal ureter. There is dilation of the renal calyces.
Analgesics are initiated.
What is the most appropriate additional treatment?
Lithotripsy
Intravenous 0.9% saline
Tamsulosin
Observation
400
A 23-year-old woman is evaluated for a 1-week history of muscle weakness. Medical history is significant for chronic migraine headaches. Medications are topiramate, sumatriptan, naproxen, and aspirin.
On physical examination, vital signs are normal. BMI is 19. The remainder of the examination is unremarkable.
Laboratory studies:
Sodium 142 mEq/L (142 mmol/L)
Potassium 3.1 mEq/L (3.1 mmol/L)
Chloride 120 mEq/L (120 mmol/L)
Bicarbonate 15 mEq/L (15 mmol/L)
Urine sodium 18 mEq/L (18 mmol/L)
Urine potassium 8.0 mEq/L (8.0 mmol/L)
Urine chloride 32 mEq/L (32 mmol/L)
What is the most likely cause of this patient's metabolic acidosis?
Surreptitious laxative use
Salicylate toxicity
Surreptitious furosemide use
Topiramate
400
A 43-year-old man is evaluated during a follow-up visit for a recent biopsy-confirmed diagnosis of IgA nephropathy. He is asymptomatic. He has no other medical problems and takes no medications.
Physical examination findings, including vital signs, are normal.
Laboratory studies:
Albumin 4.0 g/dL (40 g/L)
Creatinine 0.95 mg/dL (84 µmol/L)
Urinalysis 3+ blood; 2+ protein
24-Hour urine protein excretion 725 mg/24 h
What is the most appropriate management?
Lisinopril
Mycophenolate mofetil
Omega-3 fatty acids
Prednisone
500
A 32-year-old man is evaluated for end-stage kidney disease due to congenital reflux nephropathy. He began hemodialysis at age 21 years. He is on the kidney transplant list. He also has hypertension. Medications are amlodipine, calcitriol, lisinopril, and sevelamer carbonate.
On physical examination, vital signs are normal. There is a left upper extremity arteriovenous fistula with strong thrill. The remainder of the examination is normal.
Kidney ultrasound shows small kidneys with multiple cysts bilaterally. A few cysts have internal septations. There are no solid components or evidence of vascular flow within the cysts.
What is the most appropriate management of this patient's acquired kidney cysts?
Annual kidney ultrasonography
Bilateral nephrectomy
Tolvaptan therapy
No intervention
500
A 45-year-old woman is evaluated in the emergency department for a 3-day history of lower extremity weakness. Medical history is significant for hypertension, type 2 diabetes mellitus, and gastroesophageal reflux disease. Medications are lisinopril, metformin, canagliflozin, and pantoprazole.
On physical examination, vital signs are normal. Knee and ankle reflexes are decreased. Muscle strength is 4/5 in the lower extremities. The remainder of the examination is unremarkable.
Laboratory studies:
Creatinine 1.1 mg/dL (97.2 µmol/L)
Sodium 138 mEq/L (138 mmol/L)
Potassium 3.0 mEq/L (3.0 mmol/L)
Chloride 104 mEq/L (104 mmol/L)
Bicarbonate 23 mEq/L (23 mmol/L)
Magnesium 1.1 mg/dL (0.45 mmol/L)
What is the most likely cause of this patient's hypokalemia?
Pantoprazole
Canagliflozin
Lisinopril
Surreptitious diuretic use
500
A 46-year-old woman is evaluated for a serum creatinine level of 2.6 mg/dL (229.8 µmol/L). Her baseline serum creatinine level 3 months ago was 0.9 mg/dL (79.6 µmol/L). She has no symptoms. Two years ago, she started losartan and amlodipine for hypertension. One year ago, she started omeprazole for gastroesophageal reflux disease and naproxen for knee osteoarthritis. Eight months ago, she began atorvastatin for hyperlipidemia.
On physical examination, temperature is 37.0 °C (98.6 °F), and blood pressure is 138/86 mm Hg. The remainder of the examination is unremarkable.
Urinalysis shows the following: specific gravity 1.015; pH 5.5; 1+ erythrocytes; 3+ leukocytes; 1+ leukocyte esterase; no nitrates; and >100 leukocytes/hpf with leukocyte and granular casts.
What drugs should be discontinued in this patient?
Naproxen and omeprazole
Atorvastatin and amlodipine
Losartan and amlodipine
Losartan and omeprazole
Naproxen and atorvastatin
500
A 22-year-old woman participating in a marathon is evaluated in the medical tent for headache, confusion, and disorientation after she stopped running at mile 20. This is her first marathon.
On physical examination, temperature is 38.0 °C (100.4 °F), blood pressure is 110/72 mm Hg, pulse rate is 110/min, and respiration rate is 20/min. The patient is confused. The remainder of the examination is normal.
Laboratory studies show a serum sodium level of 130 mEq/L (130 mmol/L).
What is the most appropriate management?
100-mL bolus of 3% saline
Fluid restriction
Intravenous 0.9% saline
No treatment