Most cases of acute bacterial cystitis occur when bacteria originating in the gastrointestinal (GI) tract travel up the urethra into the bladder. In the United States alone, UTIs account for over 7 million visits to physicians annually. These ascending infections are fairly common in women but less so in men, with a female to male ratio of 30:1. This is due to the substantial length of the male urethra compared to that of the female, thus providing protection from ascending pathogens. In infants, UTIs are more common in males than females with uncircumcised males having a higher rate than those that are circumcised.

After age 50, the incidence of UTIs is similar in men and women. Predisposing factors including indwelling Foley catheters, bladder neck obstruction, prostatic urethral obstruction, instrumentation, bladder diverticula, enteric fistulas, and urachal cysts; bladder stones; and other foreign bodies leave certain males at higher risk for bacterial cystitis and put older males at higher risk than younger ones. Diabetes mellitus can also lead to a neurogenic bladder with a large capacity and incomplete voiding, which leaves these males at a higher risk as well. If these infections are not treated appropriately, they can lead to upper tract damage and in some instances, sepsis and eventual mortality.

Cystitis describes a clinical syndrome of dysuria, frequency, urgency, and occasionally suprapubic pain and/or hematuria. While this constellation of signs and symptoms points to cystitis from bacterial pathogens, other noninfectious conditions such as interstitial cystitis, bladder carcinoma, or calculi must be ruled out as well. On the other hand, not all of these symptoms need to be present for a man to have an active lower UTI.

A detailed history and physical exam usually lead to a high suspicion of bacterial cystitis. When a high clinical suspicion exists, a urinalysis and a urine culture with antimicrobial sensitivities are used to confirm the diagnosis. The urine and the urinary tract are normally free of bacteria and inflammation. False-negatives can occur in the early phases of bacterial cystitis due to the low number of white blood cells and bacteria in relationship to dilute urine. False-positives occur most commonly due to contamination in specimen acquisition. While a clean-catch specimen is the most common method of culture, this leads to higher contamination rates. Urethral catheterized specimens and suprapubic aspirates lead to lower false-positive rates, but they are not as well tolerated as clean-catch specimens and are not indicated in men unless they are unable to void.

A proper voided specimen in circumcised men requires no special preparation. In uncircumcised men, the foreskin should be retracted and the glans penis washed with an antimicrobial liquid prior to collection. The Meares-Stamey test, while more often historically referenced than actually used in clinical practice, aims to identify the location of origin of a lower UTI. It is a four-glass test in which the first 10 mL of urine are collected as a urethral culture. After voiding 200 mL, a second sample is collected midstream that represents a bladder culture. At this point a prostatic massage is performed. The secretions are sent after being milked and collected in a sterile container. The next 10 mL of voided urine is then collected immediately after the massage. This represents a prostatic culture. The localization of bacterial flora identifies an infection as urethritis, cystitis, or prostatitis. In a modified version that is more widely used in clinical practice, urine is taken before and after prostatic massage. This is known as the two-glass test.

Clean-catch urine sent for urinalysis provides vital information in diagnosing bacterial cystitis. Nitrite results only have a sensitivity of 50% but a specificity greater than 95%. Leukocyte esterase is a more sensitive test (approximately 80%), but is less specific (approximately 75%). If both a positive leukocyte esterase and nitrite are used to diagnose UTI, the specificity improves to 98%-100%, but the sensitivity declines to under 50% in some cases. On microscopic examination, the presence of more than 6 to 10 white blood cells per high-powered field indicates pyuria.

A colony count of greater than 10⁵ colony forming units (CFU)/mL of urine indicates a positive urine culture and diagnosis of an active bacterial infection in men rather than contamination. A gram stain is first reported and then a specific organism. If multiple organisms grow, then contamination should be suspected. Once sensitivities to antimicrobials are available, antibiotic therapy can be changed appropriately if prophylactic treatment was started.

In otherwise normal middle-aged men who are sexually active, a further workup including imaging with a renal and bladder ultrasound or CT scan may not be required if the infection is eradicated after a course of antibiotics. In young patients who are not sexually active or in patients with a high clinical suspicion, further workup after treatment can be done to search for a urinary tract abnormality. This includes imaging to visualize the kidneys, ureters, and bladder, a cystoscopy, and a measurement of postvoid residual volume.

For bacterial cystitis, culture-confirmed antibiotics should be prescribed for 7-10 days. The most common outpatient antibiotics used are trimethoprim-sulfamethoxazole (TMP-SMX; Bactrim, Septra) with the usual dose being one double strength tablet twice a day, a quinolone such as ciprofloxacin 500 mg twice a day, and levofloxacin 250-500 mg once daily. In fungal cystitis with Candida albicans (more common in diabetics, immunocompromised men, or men with indwelling Foley catheters), oral fluconazole 50-100 mg daily can be used for 5-7 days. In more serious infections, continuous bladder irrigation with an antifungal agent may be required.

Prostatitis is one of the most common genitourinary causes of office visits for males. It accounts for about one fourth of visits due to lower urinary tract symptoms. This equates to about 2-3 million office visits to physicians every year. The particular causes of prostatitis vary based on the acuity of inflammation and the presence of a bacterial source. Risk factors of each cause vary, with those previously listed for bacterial cystitis playing a large part in the cases involving bacterial sources. However, bacterial infection accounts for only 10% to 15% of prostatitis-related lower urinary tract pathology.

Prostatitis refers to several clinical syndromes. To simplify its classification, problems involving prostatic inflammation have been grouped into four distinct categories by the National Institute of Diabetes and Digestive and Kidney Diseases:

Category II: Chronic bacterial prostatitis

Category IIIA/IIIB: Chronic nonbacterial prostatitis/chronic pelvic pain syndrome (CPPS)

Category IV: Asymptomatic inflammatory prostatitis