Description

• Painful or inflammatory condition affecting the prostate gland with or without bacterial etiology, often characterized by urogenital pain, voiding symptoms, and/or sexual dysfunction
• Significant impact on quality of life
• <10% bacteria-proven infection
• National Institutes of Health’s (NIH) classification
  • Class I: acute bacterial prostatitis: symptomatic with fever, perineal pain, dysuria, and obstructive symptoms; polymorphonuclear leukocytes (PMNL) and bacteria in urine
  • Class II: chronic bacterial prostatitis: symptomatic chronic or recurrent bacterial infection with pain and voiding disturbances; PMNL and bacteria in expressed prostatic secretions (EPS), or urine after prostate massage, or in semen
  • Class III: chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS)
    • Inflammatory (subtype IIIA): chronic symptoms with PMNL in EPS/urine after prostate massage or in semen
    • Noninflammatory (subtype IIIB): chronic symptoms without presence of PMNL in EPS/urine after prostate massage or in semen
  • Class IV: asymptomatic inflammatory prostatitis: incidental finding during prostate biopsy; presence of PMNL and/or bacteria in EPS/urine after prostatic massage or in semen
• System(s) affected: genitourinary, renal, reproductive

Epidemiology

Incidence

• 2 million cases annually in the United States
• Bimodal peak 20 to 40 and >60 years old
• Chronic is more common in those >50 years.
• Bacterial prostatitis more frequently in HIV.

Prevalence

• Affects approximately 8.2% of males
• Lifetime probability of diagnosis >25%
• Accounts for 8% of visits to urologists and 1% of visits to primary care physicians
• Percentage of cases by class: class I: <1%, class II: 5–10%, class III: 80–90%, class IV: 10%

Etiology and Pathophysiology

• Acute bacterial prostatitis (NIH class I)
  • Likely, etiology from ascending urethral infection with intraprostatic reflux of infected urine into prostatic ducts, often associated with cystitis
  • Can occur after instrumentation of prostate
  • Usually, gram-negative bacteria (Escherichia coli [most common]; Proteus, Klebsiella, Serratia, and Enterobacter species; Pseudomonas aeruginosa)
  • Rarely, gram-positive bacteria (Staphylococcus aureus, Streptococcus, and Enterococcus species)
  • Confirmed staphylococcal prostatitis should warrant evaluation for hematogenous spread, including endovascular source.
  • Atypical bacteria include Chlamydia trachomatis, Trichomonas vaginalis, Ureaplasma urealyticum, Mycobacterium tuberculosis, and fungal etiologies in immunocompromised hosts.
  • Consider Neisseria gonorrhoeae or C. trachomatis in sexually active men <35 years.
• Chronic bacterial prostatitis (NIH class II)
  • Similar pathogens possibly higher rate of gram-positive bacteria than in acute prostatitis
  • Often as recurrent episodes of same organism
  • Progression from acute to CP is poorly understood but could result from inadequate treatment of acute prostatitis.
• CP/CPPS (NIH class III)
  • Unclear etiology with no current data to support an infectious cause
  • Inciting agent may cause inflammation or neurologic damage around prostate and leads to pelvic floor neuromuscular and/or neuropathic pain.
  • No correlation between histologic inflammation of prostate and presence or absence of symptoms
  • Patients with chronic inflammation on histology have shorter time to symptomatic progression.

Risk Factors

• Urinary tract infections (including sexually transmitted infections [STIs])
• HIV infection
• Prostatic calculi
• Urethral stricture
• Urinary catheterization: indwelling, intermittent
• Genitourinary instrumentation, including prostate biopsy (especially in patients with prior quinolone intake), transurethral resection of the prostate (TURP), cystoscopy
• Urinary retention
• Benign prostatic hypertrophy
• Unprotected sexual intercourse
• Prostate cancer

General Prevention

Antibiotic prophylaxis for genitourinary instrumentation and prostatic biopsy

Commonly Associated Conditions

• Benign prostatic hypertrophy
• Cystitis
• Urethritis
• Sexual dysfunction, including erectile dysfunction and premature ejaculation