CHAPTER 27 Prostatitis
How prevalent is prostatitis in the general population?
Two to ten percent of men are currently experiencing prostatitis. It represents anywhere from 3% to 12% of urology office visits for men, and is the most common presenting diagnosis for men younger than 50 years. Prostatitis affects men of all ages, with the highest incidence between the ages of 20 and 49 years, but there is a second increase in incidence after the age of 65 years.
What is the histologic definition of prostatitis?
An increased number of inflammatory cells within the prostatic parenchyma.
What is the most common histologic pattern of inflammation seen in prostatitis specimens?
Lymphocytic infiltrate of prostatic stroma located immediately adjacent to the acini. Presence of polymorphonuclear cells in the prostatic acini may also be seen.
Describe the 4 categories of the NIH prostatitis classification.
1. Category I describes acute bacterial prostatitis seen in patients with acute febrile illness, a new onset of significant lower urinary tract symptoms, and possibly other systemic symptoms (chills, malaise, etc).
2. Category II represents chronic bacterial prostatitis. Patients may have constant, long-term symptoms or have recurrent episodes of acute episodes of prostatitis with asymptomatic periods. The most important finding in category II prostatitis is recurrent documented UTIs.
3. Category III denotes chronic nonbacterial prostatitis, more recently termed chronic pelvic pain syndrome (CPPS). It is divided into IIIA (inflammatory CPPS) and IIIB (noninflammatory CPPS). IIIB has historically been referred to as prostatdynia.
4. Category IV refers to asymptomatic inflammatory prostatitis. It is a histologic diagnosis only, typically made after evaluation of semen, prostate chips, or prostate biopsy specimens.
What is the most common category of prostatitis?
Type III (chronic prostatitis [CP]/chronic pelvic pain syndrome [CPPS]), which accounts for 90% to 95% of cases of prostatitis.
What family of bacteria is the most common cause of category I and category II prostatitis?
The enterobacteriaceae family of rod-shaped, gram-negative organisms is the most common bacteria implicated in both acute and chronic prostatitis. It is usually a normal part of gastrointestinal flora. Escherichia coli is the most common specific pathogen in bacterial prostatitis. Other genera are Proteus, Serratia, Klebsiella, and Enterobacter.
What other pathogens have been implicated in bacterial prostatitis?
Pseudomonas (gram-negative) and enterococci (gram-positive) have been found to be the causes of bacterial prostatitis. Various other organisms that are commonly found in the urethra of unaffected males have been theorized as possible causative pathogens, including Staphylococcus species, Corynebacterium, Mycoplasma, and Ureaplasma. Other postulated organisms include Chlamydia, Candida species, and nonculturable microorganisms. Fungal prostatitis may occur in patients who are immunosuppressed. Mucorsp, Blastomyces, Cryptococcus, and Histoplasma have been described.
What role do prostatic calculi play in bacterial prostatitis?
Although prostatic calculi do not lead to symptomatic bacterial prostatitis in every patient, it has been demonstrated that they can lead to persistent bacterial prostatitis that is recalcitrant to antibiotics. This is most likely related to bacterial aggregation and biofilm production along the surface and in the interstices of the stone. They also may cause blockage of prostatic ducts, preventing drainage of the secretions.
Intraprostatic ductal reflux has been implicated as an important mechanism in the development of which categories of prostatitis? Which anatomic portion of the prostate is most susceptible to ductal reflux and why?
All categories of prostatitis are either initiated by or at least affected by ductal reflux of urine into the prostate. Reflux of bacteria into the prostate can lead to infectious prostatitis, and it has been postulated that even sterile urine leads to prostatic inflammation secondary to immunologic response, or the presence of chemical irritants in the urine itself. The ducts to the peripheral zone are more horizontally oriented and seem to reflux more easily than other regions of the prostate.
What happens to the levels of fructose, citrate, and acid phosphatase in prostatic secretions during acute bacterial prostatitis?
The levels of these entities are reduced during infection of the prostate. Protein synthesis is dramatically reduced, and the cells are unable to acquire citrate during episodes of bacterial prostatitis.
What happens to the levels of zinc and calcium in prostatic secretions during acute bacterial prostatitis?
These divalent cations are normally sequestered in the prostate cells by an active transport mechanism. These processes are reduced during active infection, and secretory levels drop.