A 55-year-old woman presents with flank pain, fever, and dysuria for the past 3 days. She has a history of recurrent urinary tract infections (UTIs) and type 2 diabetes mellitus. Physical examination reveals costovertebral angle tenderness on the right side. Urinalysis shows alkaline urine (pH 8.5), leukocyte esterase positive, and numerous white blood cells. A non-contrast CT scan reveals a staghorn calculus in the right renal pelvis. Which of the following is the most likely underlying pathophysiology?
A 62-year-old woman with a history of end-stage renal disease (ESRD) on hemodialysis, poorly controlled diabetes mellitus, and hypertension presents with confusion and generalized weakness. She has missed her last three dialysis sessions. On examination, her blood pressure is 198/95 mm Hg, and she has 3+ pitting edema bilaterally. Labs show severe hyperkalemia, hyponatremia, and metabolic acidosis. Which of the following correctly matches a sign or symptom with its likely underlying electrolyte abnormality?
A 62-year-old woman with end-stage renal disease (ESRD) on hemodialysis, hypertension, and heart failure presents to the emergency department with confusion and lethargy. She has missed her last 3 dialysis sessions due to transportation issues. On examination, her blood pressure is 198/96 mm Hg, she has bilateral rales on lung auscultation, and 2+ pitting edema in her lower extremities. She is disoriented to time and place. You suspect her altered mental status is related to electrolyte imbalances from missed dialysis. Which choice correctly pairs a sign or symptom with its potentially causative electrolyte abnormality in this patient?
A 70-year-old man with a history of benign prostatic hyperplasia (BPH) presents to the emergency department with decreased urine output and lower abdominal discomfort for the past two days. Physical examination reveals suprapubic tenderness and a distended bladder. Laboratory studies show: Serum creatinine: 3.2 mg/dL (baseline: 1.0 mg/dL) Blood urea nitrogen (BUN): 45 mg/dL Urine osmolality: 280 mOsm/kg Urine sodium: 50 mEq/L Fractional excretion of sodium (FENa): 3% Urinalysis: No casts or protein Which of the following best describes the underlying cause of this patient’s kidney injury?
A 42-year-old man comes to the clinic reporting dark brown urine and a recent flu-like illness. He has no known medical history and is not on any medications. His serum creatinine is elevated at 3.0 mg/dL from a presumed baseline of 0.8 mg/dL. Urinalysis shows muddy brown casts. What is the most likely diagnosis based on the urinalysis findings in this context?
A 55-year-old woman with a history of diabetes mellitus type 2 presents with nausea, vomiting, and lethargy. She has not been able to keep down fluids for the last 2 days. Her blood pressure is low, and labs show a serum creatinine increase from 1.2 mg/dL to 2.8 mg/dL, with a BUN to creatinine ratio of 30:1. Which diagnostic test should be prioritized to evaluate this patient’s AKI?
A 60-year-old man presents with flank pain, nausea, and difficulty urinating for 2 days. His past medical history includes benign prostatic hyperplasia (BPH). Examination reveals a distended bladder and tender lower abdomen. Serum creatinine is 3.2 mg/dL (baseline 1.0 mg/dL), and urinalysis is unremarkable. What is the most appropriate initial investigation to confirm the cause of his AKI?
A 75-year-old woman with a history of hypertension and heart failure presents to the emergency department with confusion and reduced urine output over the past three days. She was recently started on furosemide for worsening leg swelling. On physical examination, the patient is confused but hemodynamically stable. Laboratory results are as follows: Serum sodium: 134 mEq/L Serum creatinine: 2.1 mg/dL (baseline: 1.0 mg/dL) Blood urea nitrogen (BUN): 45 mg/dL Urine sodium: 12 mEq/L Urine creatinine: 40 mg/dL Urine osmolality: 570 mOsm/kg Which of the following is the most likely cause of this patient’s acute kidney injury (AKI)?
A 75-year-old woman is admitted with severe diarrhea, decreased urine output, and dizziness. On examination, she is hypotensive with dry mucous membranes. Laboratory tests reveal serum creatinine of 2.0 mg/dL (baseline 0.8 mg/dL), blood urea nitrogen (BUN) of 48 mg/dL, and fractional excretion of sodium (FENa) of 0.8%. Urinalysis shows no significant abnormalities. What is the most likely cause of this patient’s AKI?
A 65-year-old man with a history of hypertension presents with a 2-day history of decreased urine output and fatigue. On examination, he appears euvolemic. Blood tests show an increase in serum creatinine from 0.9 mg/dL (baseline) to 1.3 mg/dL over the past 48 hours. His urine output is 400 mL in the last 24 hours. Which of the following meets the diagnostic criteria for acute kidney injury (AKI)?
