A 32-year-old Caucasian male with a past medical history significant for asthma presents to the emergency room complaining of inability to urinate. His physical exam is remarkable for mild wheezing,...

A 32-year-old Caucasian male with a past medical history significant for asthma presents to the emergency room complaining of inability to urinate. His physical exam is remarkable for mild wheezing, which he reports as unimproved despite exceeding the recommended dose of his anticholinergic rescue inhaler. His DRE reveals a smooth unenlarged prostate with no palpable masses. What is the likely etiology for this patient’s urinary retention?

A. Drug side effect

B. Chronic prostatitis

C. Prostatic carcinoma

D. BPH