Chronic Bacterial Prostatitis

Background

• The term prostatitis encompasses a number of disorders of the prostate and may be infectious or noninfectious, acute or chronic.
• Chronic bacterial prostatitis (CBP) accounts for about 10% of chronic prostatitis syndromes and refers to recurrent or ongoing bacterial infection of the prostate usually lasting > 3 months.
• CBP is distinct from chronic prostatitis/chronic pelvic pain syndrome, which accounts for about 90% of chronic prostatitis syndrome and is of unknown cause.
• CBP is most often caused by uropathogens, such as Escherichia coli, other gram-negative rods, and Enterococcus but sexually-transmitted pathogens such as Chlamydia trachomatis can also cause the disease.
• Common symptoms include pain with urination, straining to void, increased urinary frequency, and prostatic pain.
• Symptoms may be continuous or intermittent and patients may note a history of recurrent urinary tract infections.
• On physical examination, the prostate may be enlarged, boggy, and tender to palpation but abnormalities are not always found.

Evaluation

• Initial evaluation of a patient with suspected chronic bacterial prostatitis (CBP) should include a urinalysis and urine culture to establish the presence of infection.
• The best method for localizing the infection to the prostate is not clear. Most methods are based on the detection of a higher concentration of bacteria in prostatic secretions compared to urine.
• The traditional test is the Meares-Stamey 4-glass test which involves performing a Gram stain and quantitative culture on 4 urine samples, 2 before and 2 after a 1-minute prostatic massage.
• A modified 2-glass test is an alternative:
  • only premassage midstream urine and postmassage urine samples are compared
  • sensitivity and specificity are similar to the Meares-Stamey 4-glass test
• Due to the difficulty of obtaining adequate specimens, the diagnosis is often made presumptively based on compatible clinical findings and the presence or history of recurrent urinary tract infection.
• Patients with risk factors for sexually transmitted infections (STI) should also be screened for chlamydia and other STIs.
• Blood tests are not often helpful; prostate-specific antigen (PSA) may be elevated but is a nonspecific finding.

Management

• Antibiotic selection should be based on the identity and susceptibility of the isolated organism as well as the drug's ability to penetrate the prostate.
  • Fluoroquinolones, such as levofloxacin 500 mg/day orally or ciprofloxacin 400 mg orally twice daily (based on normal renal function), are first-line for susceptible uropathogens, such as Escherichia coli or other gram-negative rods.
  • Cotrimoxazole (trimethoprim-sulfamethoxazole) is an alternative.
  • For sexually transmitted pathogens, such as Chlamydia trachomatis and genital mycoplasma, recommended options include levofloxacin, azithromycin, and doxycycline.
• Recommended duration of therapy is 4-6 weeks but courses as long as 12 weeks can be considered.
• With antibiotic treatment symptoms resolve in about 70%-90% of patients. About 30% of patients will relapse.
• For patients with persistent symptoms despite therapy, consider retreatment if bacteria remains present in urine, imaging for complications such as prostatic abscess, and urology consultation.