Prostatic fluid for diagnosis of prostatitis

The diagnosis of and management of chronic prostatitis is very difficult. Identification of specific microbiologic etiology is hindered by difficulty of obtaining samples. The technique most often used by urologists in eastern health is digital prostatic massage resulting in prostatic fluid expressed from the urethral opening.

Occasionally samples are submitted for the investigation of fertility. These are usually labeled “semen” or “sperm” and are processed differently. See Semen.

Setup

Direct Examination

Not routinely performed. If specifically requested and approved by charge technologist or microbiologist, perform Gram stain directly on unspun specimen.

Culture

Process as a urine using both 1 and 10 µL loops.

Mix the urine specimen and dip a sterile calibrated 1 µL loop vertically into the sample. Streak the loop down the centre of the plate and then cross-streaked at a 90° angle to the inoculum (colony count streak pattern). Repeat the process using a 10 µL loop.

Media Incubation
Blood Agar (BA) O2, 35°C x 24 hours
MacConkey Agar (MAC) O2, 35°C x 24 hours

Interpretation

Cultures with no growth

Discard no growth cultures after 18-24 hrs incubation.

Cultures with growth

1 colony from 1µL sample = 1 x 106 CFU/L.
1 colony from 10 µL sample = 0.1 x 106 CFU/L.
If the colony count is <1 x 106 CFU/L report as such. Do not change the exponent.

Quantitate and identify with susceptibilities all Potential Uropathogens.
Quantitate, minimal workup for ID (no susceptibility) of Non-uropathogens.

Potential Uropathogens

  • Enterobacteriaceae
  • Pseudomonas aeruginosa
  • Other gram negative bacilli
  • Enterococcus spp.
  • beta-haemolytic streptococci
  • Staphylococcus aureus
  • Staphylococcus saprophyticus
  • Streptococcus pneumoniae
  • Yeast
  • Corynebacterium urealyticum
  • Aerococcus urinae – only considered a pathogen when predominant (in amounts greater than 10 times non-pathogens)
  • Other CNS – only considered a pathogen when predominant (in amounts greater than 10 times non-pathogens)

Non-uropathogens (normal skin/urogenital flora)

  • Lactobacillus spp.
  • diphtheroids (not C. urealyticum)
  • viridans Streptococci (not A. urinae)
  • Bacillus spp.

Reporting

Gram Stain (if requested)

“(No) WBCs seen. (No) Bacteria seen” (without quantitation)

Culture

No growth report: “No growth”

Growth without work-up: “No significant growth”

Growth with work-up

Preliminary report: Morphologic description of organism with corresponding colony count/L for each organism.

Final report: Organism name with corresponding colony count/L for each organism and susceptibility testing results.