A 60-Year-Old Man Comes to the Physician Because of Urinary

A 60-year-old man comes to the physician because of urinary frequency and perineal pain for the past 2 days. His temperature is 39.1°C (102.3°F) . His penis and scrotum appear normal. Digital rectal examination shows a swollen, exquisitely tender prostate.   Evaluation revealed acute prostatitis, and urine culture was positive for Escherichia coli that was sensitive to fluroquinolones. He strarted on oral ciprofloxacin. He has a history of intermitent of heartburn for which he takes an over-the-counter antacid. After two days, he comes back to the office for recurrent fever and dysuria. Physical examination shows a mildly enlarged and tender prostate.  Repeat urine culture grows E coli.  Which of the following is the most likely cause of this patient's recurrent symptoms?

A) Acquired antibiotic resistance
B) Decreased drug bioavailability
C) Exposure to untreated sexual partner
D) Increased renal drug clearance
E) Induction of hepatic CYP enzymes