What could be the causes of urinary tract infections in elderly men?

UTI isUnusual in men: The infection usually tracks upwards through the urethra. Causes may include sexual activity, non circumcision with suboptimal hygiene, or unknown. In men however, a UTI may warrant ultrasound to rule out a structural abnormality like a stone since UTI is not common in men like in women.

Enlarged prostate: Prostatic enlargement can lead to progressive urethral + bladder neck obstruction leading to impaired bladder drainage + various degrees of urinary retention. Also can develop bladder diverticula (outpouchings) from increased voiding pressures in bladder, which do not empty with urination. Retained urine "stagnates" and is fertile ground for utis.