A 64-year-old man is brought to the emergency department because of dull lower abdominal pain for 3 hours. He has not urinated for 24 hours and has not passed stool for over 3 days. Medical history is significant for diet-controlled type 2 diabetes and degenerative arthritis of the knee. Physical examination shows a tender, palpable suprapubic mass. Bowel sounds are hypoactive. Abdominal ultrasound shows a large anechoic mass in the pelvis. Mild bilateral costophrenic angle tenderness is present. Laboratory results show a blood urea nitrogen level of 32 mg/dL and creatinine level of 2.6 mg/dL. Four weeks ago, laboratory studies were normal. Which of the following is the most likely cause of this patient's renal dysfunction?

Question

A 64-year-old man is brought to the emergency department because of dull lower abdominal pain for 3 hours. He has not urinated for 24 hours and has not passed stool for over 3 days. Medical history is significant for diet-controlled type 2 diabetes and degenerative arthritis of the knee. Physical examination shows a tender, palpable suprapubic mass. Bowel sounds are hypoactive. Abdominal ultrasound shows a large anechoic mass in the pelvis. Mild bilateral costophrenic angle tenderness is present.  Laboratory results show a blood urea nitrogen level of 32 mg/dL and creatinine level of 2.6 mg/dL.  Four weeks ago, laboratory studies were normal.  Which of the following is the most likely cause of this patient's renal dysfunction?

Quizplus · Accepted Answer

Eductional Objective: Acute urinary retention is characterized by anuria and bladder distension and can result in hydronephrosis and acute kidney injury.  A palpable, distended bladder is present on examination, and abdominal and flank pain may be present.  The most common cause of urinary retention is bladder outlet obstruction (urethral compression) due to benign prostatic hyperplasia.

A 64-Year-Old Man Is Brought to the Emergency Department Because