ROSH Gastrointestinal Practice Exam

Which antibiotic is the most appropriate for a 64-year-old man with a urinary tract infection and a history of benign prostatic hyperplasia?

1. Cephalexin

2. Nitrofurantoin

3. Phenazopyridine

4. Trimethoprim-sulfamethoxazole

The correct answer is: Cephalexin

In the context of treating a urinary tract infection (UTI) in a 64-year-old man with benign prostatic hyperplasia (BPH), cephalexin is often considered an appropriate choice. Cephalexin is a first-generation cephalosporin antibiotic that is effective against a variety of bacteria commonly responsible for UTIs. It works by inhibiting cell wall synthesis in bacteria, making it effective against both gram-positive and some gram-negative organisms. One important aspect to consider in patients with BPH is that they often experience urinary retention, which can lead to a higher risk of developing UTIs from bacteria that can proliferate in stagnant urine. The choice of antibiotic should take into account the potential for antibiotic resistance and the infection's likely causative organisms, which cephalexin can adequately cover. Other options, while viable in various scenarios, may not be as suitable for this specific patient. For example, nitrofurantoin is generally recommended for uncomplicated UTIs, but its use can be limited in cases of renal impairment, which is more common in older populations. Trimethoprim-sulfamethoxazole could be effective, but there is also increased resistance seen with certain pathogens, particularly in the elderly. Phenaz