Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (1335 page)

   Positive cultures are now most commonly detected by staining fixed monolayers with specific anti–
C
.
trachomatis
antibodies; positive cultures

show staining of intracellular inclusions. The sensitivity of cultures for
C
.
trachomatis
detection is improved by blind subculture of a primary culture after the initial incubation.

   
Turnaround time:
Cultures are incubated for 72 hours. An additional 48–72 hours are required if primary cultures are subcultured prior to final examination.

   Special Collection and Transport Instructions

   It is critical to collect infected epithelial cells from infected sites using toxicity-tested swabs or other device. Swabs may be premoistened with sterile nonbacteriostatic saline before specimen collection. Scrapings or biopsy specimens may be submitted for some specimen types. (See specimens below.)

   Place specimens into a
Chlamydia
transport medium, such as 2-SP, and transport to the laboratory at 4°C. Deliver to the laboratory as quickly as possible.

   Specimens commonly submitted for
Chlamydia
culture come from the following sites:

   
Cervix:
Remove excess mucus from the exocervix. Insert a new swab approximately 1 cm into the cervical canal and gently rotate for 10–15 seconds.

   
Urethra:
Clean the distal urethra and meatus with a swab. Insert a new thinshafted swab 2–4 cm into the urethra and gently rotate for 10–15 seconds.

   
Conjunctiva:
Remove excess purulent discharge with a swab. With a new swab, gently rotate over the affected conjunctival surface.

   
Anus:
Insert a premoistened swab into the anorectal juncture and rotate gently. The swab should not be heavily stained with feces.

   
Fallopian tube or epididymis:
Place aspirate into an equal volume of
Chlamydia
transport media.

   
Respiratory tract (neonate):
Place aspirate or wash into an equal volume of
Chlamydia
transport media.