A middle-aged African-American man presents with discomfort between the scrotum and anus along with fever. What is the likely diagnosis?

The presentation of discomfort between the scrotum and anus, accompanied by fever, strongly suggests prostatitis. This condition typically involves inflammation of the prostate gland and is often characterized by symptoms such as perineal pain, fever, and urinary issues. Given the age and demographic of the patient, and the specific symptoms described, prostatitis is the likely diagnosis.

Prostate cancer can present with pain or discomfort in the pelvic area, but it is less typically associated with fever, making it a less likely diagnosis in this acute context. Hemorrhoids may cause discomfort in the anal region but would not typically present with fever. A urinary tract infection could cause discomfort in the pelvic area as well, but it is more often associated with urinary symptoms like dysuria, urgency, or frequency, rather than isolated perineal discomfort and fever, which align more closely with prostatitis.

Therefore, the combination of the specific symptoms and the demographic factors indicates that prostatitis is the most plausible diagnosis.