A
An 84-year-old woman is evaluated during a follow-up visit for stage G4 chronic kidney disease. Her only symptom is lack of energy. She is independent in her activities of daily living. She has declined renal replacement therapy after attending a dialysis education class. She understands the process and purpose of dialysis and the consequence of non-treatment but prefers non-dialytic therapy. Medical history is also significant for diabetes mellitus, heart failure, hypertension, and stroke. Medications are furosemide, lisinopril, hydralazine, insulin aspart, insulin detemir, nifedipine, metoprolol, and aspirin, 81 mg.
On physical examination, blood pressure is 160/72 mm Hg, and pulse rate is 60/min; other vital signs are normal. Cardiac examination reveals an S4. The remainder of the examination is noncontributory.
Laboratory studies:
Calcium
9.4 mg/dL (2.4 mmol/L)
Creatinine
2.3 mg/dL (203.3 µmol/L)
Potassium
4.7 mEq/L (4.7 mmol/L)
Phosphorus
4.4 mg/dL (1.4 mmol/L)
Estimated glomerular filtration rate
26 mL/min/1.73 m2
Which of the following is the most appropriate management?
Add a phosphate binder
Discontinue all medications except insulin
Intensify hypertension management
Refer for hospice care
A 26-year-old man is referred for an elevated serum creatinine level of 1.4 mg/dL (123.8 µmol/L) that was measured when he presented to an urgent care center for flank pain. The flank pain was determined to be musculoskeletal and caused by a weight-lifting injury. A subsequent urinalysis was normal, and a random urine albumin-creatinine ratio was 10 mg/g. He reports that he takes no creatine supplements but is evasive when questioned about anabolic steroid use. His medical history is otherwise unremarkable, and he takes no prescribed medications.
On physical examination, vital signs are normal. BMI is 29. The patient is muscular, with no evidence of subcutaneous fat. He has mild muscle tenderness in the right lower back. The remainder of the examination is unremarkable.
Which of the following is the most appropriate test to perform next?
Blood urea nitrogen measurement
Creatinine clearance
Radionuclide imaging
Serum cystatin C measurement
A 31-year-old woman is evaluated during a follow-up visit for progressive autosomal dominant polycystic kidney disease. She has a recent history of an infected kidney cyst. She also has hypertension. Family history is significant for end-stage kidney disease in her father at 50 years of age due to autosomal dominant polycystic kidney disease. Her only medication is lisinopril.
On physical examination, vital signs are normal. Abdominal examination reveals a palpable kidney on the right side. The remainder of the examination is unremarkable.
Laboratory studies show a serum creatinine level of 1.3 mg/dL (114.9 µmol/L), representing a decrease in estimated glomerular filtration rate of >5 mL/min/1.73 m2 from 1 year ago. Liver chemistry tests are normal.
Which of the following is the most appropriate management?
Discontinue lisinopril; start telmisartan
Obtain ultrasonography of the kidneys
Start octreotide
Start tolvaptan
A 46-year-old woman is evaluated during a follow-up visit for hypertension, type 2 diabetes mellitus, and stage G3 chronic kidney disease. She reports no symptoms. Medications are losartan, amlodipine, metformin, canagliflozin, and rosuvastatin.
On physical examination, blood pressure is 124/72 mm Hg. Other vital signs and the remainder of the examination are unremarkable.
Laboratory studies:
Creatinine
1.6 mg/dL (141.4 µmol/L)
Electrolytes :
Sodium
136 mEq/L (136 mmol/L)
Potassium
5.6 mEq/L (5.5 mmol/L)
Chloride
104 mEq/L (104 mmol/L)
Bicarbonate
24 mEq/L (24 mmol/L)
Urine albumin-creatinine ratio
320 mg/g
ECG is normal.
The patient is counseled to start a low potassium diet.
Which of the following is the most appropriate management?
Add hydrochlorothiazide
Add patiromer
Administer intravenous calcium gluconate
No further treatment
A 32-year-old woman is seen following evaluation for a single episode of painless hematuria that she noted last week. She has chronic kidney disease secondary to chronic tubulointerstitial nephritis confirmed by biopsy. She took Chinese herbal weight loss pills daily for 3 years. She took acetaminophen or ibuprofen for arthralgia three or four times monthly for 5 years. Since the kidney biopsy, she has discontinued all drugs and supplements. She has no other medical problems.
The physical examination, including vital signs, is normal.
Urinalysis shows a specific gravity of 1.012, 3+ blood, 1+ protein, 1+ leukocytes, 25-50 nondysmorphic erythrocytes/hpf, 3-5 leukocytes/hpf, and no casts; urine culture is negative.
CT scan of the abdomen and pelvis shows normal kidneys and collecting system.
Which of the following is the most appropriate management?
Cystoscopy with retrograde pyelography
MRI of the kidneys
Renal angiography
Observation
A 67-year-old man is evaluated during a follow-up visit 4 weeks after being diagnosed with the nephrotic syndrome. He has a 7-year history of well-controlled type 2 diabetes mellitus with no retinopathy, neuropathy, or clinically evident vascular disease. He has no other medical problems, and his only medication is metformin.
On physical examination, blood pressure is 110/60 mm Hg; other vital signs are normal. No rash is noted. There is 2-mm pitting edema in the lower extremities to the knees bilaterally.
Laboratory studies:
Albumin
2.1 g/dL (21 g/L)
Total cholesterol
330 mg/dL (8.5 mmol/L)
Creatinine
1.4 mg/dL (123.8 µmol/L) (4 months ago, 1.0 mg/dL [88.4 µmol/L])
Hemoglobin A1c
6.9%
Serum protein electrophoresis
Negative
24-Hour urine protein excretion
12,000 mg/24 h
Kidney biopsy shows expansion of the mesangial areas by deposits of homogenous, pale eosinophilic material that are positive with Congo red staining and demonstrate apple-green birefringence when viewed under polarized light.
Which of the following is the most likely diagnosis?
Diabetic kidney disease
IgA nephropathy
Membranous nephropathy
Renal AL amyloidosis
A 45-year-old woman is evaluated during a follow-up visit for newly diagnosed severe hypertension. She began low-dose hydrochlorothiazide and amlodipine therapy 1 month ago. There is no family history of hypertension. She has no other medical problems and takes no other medications.
On physical examination, blood pressure is 164/100 mm Hg in both arms, pulse rate is 76/min, and respiration rate is 18/min. BMI is 24. The remainder of the examination is normal.
Laboratory studies:
Bicarbonate
30 mEq/L (30 mmol/L)
Creatinine
0.9 mg/dL (79.6 µmol/L)
Potassium
2.9 mEq/L (2.9 mmol/L)
Sodium
138 mEq/L (138 mmol/L)
Urinalysis
No blood or protein
Which of the following is the most appropriate diagnostic test to perform next?
Plasma aldosterone concentration/plasma renin activity ratio
Plasma fractionated metanephrines measurement
Renal artery CT angiography
24-Hour urine free cortisol measurement
A 31-year-old woman seeks preconception counseling. She has systemic lupus erythematosus and lupus nephritis, both of which have been stable for the past year; she has had no proteinuria for more than 12 months. She currently feels well. Medications are mycophenolate mofetil, hydroxychloroquine, and low-dose prednisone.
Physical examination findings, including vital signs, are normal.
Which of the following medications should be discontinued in this patient before conception?
Hydroxychloroquine
Mycophenolate mofetil
Prednisone
No change in medication is required
A 69-year-old man is evaluated 7 days after starting nafcillin to treat a culture-proven methicillin-sensitive Staphylococcal aureus sternal wound infection. The infection was diagnosed 10 days after coronary artery bypass surgery. History is significant for diabetes mellitus. Other medications are aspirin, metformin, metoprolol, atorvastatin, and acetaminophen as needed.
On physical examination, vital signs are normal. The sternal wound appears to be healing, with minimal tenderness and redness and decreased drainage. The remainder of the examination is unremarkable.
Laboratory studies:
C3
61 mg/dL (610 mg/L)
C4
13 mg/dL (130 mg/L)
Creatinine
2.0 mg/dL (176.8 µmol/L); before hospital admission: 0.9 mg/dL (79.6 µmol/L)
Urinalysis
3+ blood; 2+ protein; 30-40 erythrocytes/hpf; 2-5 leukocytes/hpf; dysmorphic erythrocytes; rare erythrocyte casts
Kidney biopsy shows a mild proliferative glomerulonephritis with infiltrating neutrophils, granular C3, and IgG and IgM staining on immunofluorescence; hump-shaped subepithelial electron-dense deposits are seen on electron microscopy.
Which of the following is the most appropriate treatment?
Add lisinopril
Add prednisone
Continue nafcillin
Initiate sodium restriction and furosemide
An 81-year-old woman is evaluated in the emergency department for abrupt onset of lower extremity edema that began 2 weeks ago and has progressed to generalized edema. Medical history is significant for hypertension. Her only medication is amlodipine.
On physical examination, vital signs are normal. There is periorbital edema, ascites, and pitting edema of the forearms and lower extremities to the thighs. The remainder of the examination, including cardiovascular and pulmonary examinations, is unremarkable.
Laboratory studies:
Albumin
1.6 g/dL (16 g/L)
Total cholesterol
364 mg/dL (9.4 mmol/L)
Creatinine
2.8 mg/dL (248 µmol/L); 2 months ago: 0.7 mg/dL (61.9 µmol/L)
Urinalysis
No blood; 4+ protein
Kidney ultrasound with Doppler shows normal-sized echogenic kidneys with no hydronephrosis; there are no abnormalities on Doppler flow.
Which of the following is the most likely diagnosis?
ANCA-associated glomerulonephritis
Anti–glomerular basement membrane antibody disease
Membranous nephropathy
Minimal change glomerulopathy
A 23-year-old woman is evaluated during a follow-up visit for focal segmental glomerulosclerosis that was diagnosed 3 weeks ago. The edema in her lower extremities has not improved on her current regimen of prednisone, losartan, atorvastatin, and maximal doses of oral furosemide.
On physical examination, vital signs are normal. The patient weighs 72 kg (158.7 lb). There is 3-mm pitting edema of the lower extremities through the mid-thigh, equal on both sides. The remainder of the examination is unremarkable.
Laboratory studies:
Albumin
2.0 g/dL (20 g/L)
Total cholesterol
303 mg/dL (7.8 mmol/L)
Creatinine
0.6 mg/dL (53 µmol/L)
Urine protein-creatinine ratio
9150 mg/g
CT of the chest is normal.
Which of the following is the most appropriate management?
Add metolazone
Administer furosemide by continuous intravenous infusion
Administer furosemide by intravenous bolusD
Discontinue prednisone; add cyclosporine
Hemodialysis with ultrafiltration
A 60-year-old woman is evaluated during a follow-up visit for stage G3 proteinuric chronic kidney disease due to type 2 diabetes mellitus. Medications are lisinopril and metformin.
On physical examination, blood pressure is 137/80 mm Hg, and pulse rate is 83/min; other vital signs are normal. The remainder of the examination is normal.
Laboratory studies:
Hemoglobin A1c
8.3%
Creatinine
1.3 mg/dL (114.9 µmol/L)
Potassium
4.3 mEq/L (4.3 mmol/L)
Estimated glomerular filtration rate
45 mL/min/1.73 m2
Spot urine protein-creatinine ratio
3680 mg/g
Which of the following is the most appropriate additional treatment?
Canagliflozin
Glyburide
Losartan
Pioglitazone
Sitagliptin
A 37-year-old woman is evaluated for a new-onset headache. She describes the headache as a steady pain located in the front of her head, bilaterally, and not associated with any other symptoms. The headache has been present for more than 24 hours. She is in the third trimester of her first pregnancy. Until now, her pregnancy has been unremarkable and she has otherwise been healthy.
On physical examination, blood pressure is 145/95 mm Hg; other vital signs are normal. There is no papilledema. On abdominal examination, the patient has a gravid uterus consistent with her stage of pregnancy, and there is no abdominal tenderness. Neurologic examination is normal.
Laboratory studies:
Hemoglobin
12.3 g/dL (123 g/L)
Platelet count
156,000/µL (156 × 109/L)
Alanine aminotransferase
Normal
Aspartate aminotransferase
Normal
Creatinine
1.4 mg/dL (123.8 µmol/L)
Random urine protein-creatinine ratio
125 mg/g
Which of the following is the most likely diagnosis?
Acute fatty liver of pregnancy
Migraine headache
Pheochromocytoma
Preeclampsia
An 87-year-old man is hospitalized for the inability to void. He has a 4-year history of urinary hesitancy and dribbling. He lives alone with the assistance of a nephew but finds it increasingly difficult to live independently. He has no other medical history and takes no medications.
On physical examination, he is thin and frail appearing. Blood pressure is 158/64 mm Hg, and pulse rate is 78/min without orthostatic changes. BMI is 22. The prostate is diffusely enlarged. There is 1+ lower extremity edema. Generalized weakness is noted. The remainder of the examination is unremarkable.
A bladder catheter drains 850 mL of urine.
Laboratory studies show a blood urea nitrogen level of 133 mg/dL (47.5 mmol/L) and a serum creatinine level of 8.9 mg/dL (786.8 µmol/L).
Kidney ultrasound shows an 8.3-cm right kidney and a 7.9-cm left kidney, marked cortical echogenicity and thinning, and moderate-severe hydronephrosis.
During the first 24 hours, urine output with the bladder catheter in place is 1240 mL. Follow-up bladder ultrasound shows less than 50 mL of residual urine. On hospital day 2 the urine output is 340 mL.
On hospital day 3, the serum creatinine level is 8.2 mg/dL (724.8 µmol/L). Repeat kidney ultrasound shows persistent hydronephrosis.
Which of the following is the most appropriate next step in management?
Discuss goals of care
Initiate intravenous 0.9% saline
Obtain noncontrast CT of abdomen and pelvis
Place bilateral ureteral stents
A 33-year-old man is evaluated for acute kidney injury 48 hours after being hospitalized for herpes simplex virus encephalitis. Diagnosis was confirmed with polymerase chain reaction testing of the cerebrospinal fluid. He is being treated with intravenous high-dose acyclovir. Empiric therapy with ceftriaxone plus vancomycin was initiated and then discontinued after the results of the cerebrospinal fluid analysis became available. Medical history is significant for chronic kidney disease due to hereditary nephritis and hypertension. Outpatient medications are lisinopril and hydrochlorothiazide, both held since admission.
On physical examination, vital signs are normal. The patient has some difficulty with attention and orientation to time but is otherwise neurologically intact. The remainder of the examination is normal.
Current laboratory studies:
Creatinine
2.3 mg/dL (203.3 µmol/L); baseline: 1.8 mg/dL (159.1 µmol/L)
Electrolytes:
Sodium
137 mEq/L (137 mmol/L)
Potassium
5.6 mEq/L (5.6 mmol/L)
Chloride
102 mEq/L (102 mmol/L)
Bicarbonate
26 mEq/L (26 mmol/L)
Urinalysis
Specific gravity 1.010; pH 7.5; 1+ blood; 2+ protein; 1+ leukocytes; 1-3 leukocytes/hpf; 3-5 erythrocytes/hpf; fine-needle crystals
Kidney ultrasound shows an 11-cm right kidney and an 11.8-cm left kidney with normal cortical appearance and without hydronephrosis.
Which of the following is the most likely cause of this patient's acute kidney injury?
Acute glomerulonephritis
Acute interstitial nephritis
Acute tubular necrosis
Intratubular obstruction
A 52-year-old woman is evaluated in the emergency department for abdominal pain and metabolic acidosis. The patient has been drinking alcohol steadily for 1 week and has been brought to the emergency department by friends. The patient also had episodes of nausea and vomiting and abdominal pain over the past 24 to 48 hours. The patient was hospitalized 1 year ago with isopropyl alcohol intoxication. She reports no other medical problems and takes no medications.
On physical examination, blood pressure is 110/72 mm Hg, pulse rate is 110/min, and respiration rate is 20/min. BMI is 18. Abdominal examination reveals diffuse tenderness to palpation. The remainder of the examination is normal.
Laboratory studies:
Blood urea nitrogen
32 mg/ dL (11.4 mmol/L)
Electrolytes :
Sodium
139 mEq/L (139 mmol/L)
Potassium
3.9 mEq/L (3.9 mmol/L)
Chloride
100 mEq/L (100 mmol/L)
Bicarbonate
11 mEq/L (11 mmol/L)
Ethanol
40 mg/dL (8.64 mmol/L)
Glucose
72 mg/dL (4.0 mmol/L)
Plasma osmolality
305 mOsm/kg H2O
Urinalysis
Specific gravity 1.030; pH 5.5; no blood; trace ketones
Which of the following is the most likely diagnosis?
Alcoholic ketoacidosis
Ethylene glycol toxicity
Isopropyl alcohol toxicity
Methanol toxicity