Segmental Cultures of the Lower Urinary Tract (Four Glass or Stamey Test)

 

Steps:

(1) No antibiotics are taken for 1 week prior to testing.

(2) Advise the patient not to ejaculate for at least 2 days prior to testing.

(3) The patient retains urine for a short period, typically about 2 hours.

(4) The end of the penis and urethral orifice are cleaned with sterile saline or water.

(5) A first voided specimen (5-10 mL) is collected and designated "urine specimen 1."

(6) The patient continues voiding and is allowed to pass 100-200 mL.

(7) A mid-stream specimen (5-10 mL) is collected and designated "urine specimen 2."

(8) The specimen then stops urinating.

(9) The prostate is then palpated. If hot and swollen, indicating acute prostatitis, then no further testing is performed. Else the prostate is carefully massaged with "milking" of secretions.

(10) The expressed prostatic secretions from the massage are collected and designated "prostatic secretions."

(11) The urethral orifice is again cleaned with sterile saline or water.

(12) The patient is then instructed to urinate and the first 5-10 mL is collected and designated "urine specimen 3."

(13) The patient continues urinating to completion.

(14) Each of the specimens is examined for white blood cells and is submitted for quantitative cultures. The cultures should be set up as quickly as possible after collection to minimize bacterial growth.

 

Evaluation of expressed prostatic secretions (EPS):

(1) Normally the secretions show a WBC count 0-2 per high powered field (hpf, x400 objective).

(2) Inflammation is considered significant if it is (a) >= 10 WBC per hpf (some use >= 15), or (b) >= 1,000 per µL.

(3) Lipid-laden macrophages are rare in normal secretions but are fairly common in chronic prostatitis.

 

Ideally the first 2 specimens should show no or rare WBCs and be sterile. If the first two urine specimens show pyruia and/or bacteriuria, then the patient should be evaluated as a urinary tract infection. If symptoms persist after treatment, then testing is repeated (as above).

 

Prostatic massage in a patient with acute prostatitis can result in bacteremia in the patient (and possibly physical assault of the massaging physician).

 

Chronic bacterial prostatitis:

(1) WBCs in EPS: >= 10 per high powered field

(2) quantitative culture of EPS: positive

(3) WBCs in urine specimen 3: (WBCs in specimen 3) – (WBCs in specimen 2) >= 10 per hpf

(4) quantitative culture of urine specimen 3: ratio (count specimen 3) / (count specimen 2) >= 10

 

Chronic nonbacterial prostatitis (chronic pelvic pain syndrome, inflammatory):

(1) WBCs in EPS: >= 10 per high powered field

(2) quantitative culture of EPS: negative

(3) WBCs in urine specimen 3: (WBCs in specimen 3) – (WBCs in specimen 2) >= 10 per hpf

(4) quantitative culture of urine specimen 3: ratio (count specimen 3) / (count specimen 2) < 10

 

Prostadynia (chronic pelvic pain syndrome, noninflammatory):

(1) WBCs in EPS: < 10 per high powered field

(2) quantitative culture of EPS: negative

(3) WBCs in urine specimen 3: (WBCs in specimen 3) – (WBCs in specimen 2) < 10 per hpf

(4) quantitative culture of urine specimen 3: ratio (count specimen 3) / (count specimen 2) < 10

 

Limitations:

• Many patients may not have prostatic secretions after the prostatic massage.

• The WBC counts and quantitative cultures need to be standardized to give meaningful results.

• Normal males may have a mild elevation of WBC in the prostatic secretions for up to 2 days after ejaculation, so the pretest instructions must be carefully adhered to.