Presented by John R. Papp, Senior Service Fellow, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, at the 2010 National Chlamydia Coalition meeting

1. Laboratory Recommendations for the Detection of
Chlamydia trachomatis, Neisseria gonorrhoeae
Top Changes from 2002 Guidelines
(besides the title)

2. CT / GC Recommendations:
Infections of the Reproductive Tract (Female)
2002
 A nucleic acid amplification test (NAAT) performed on an
endocervical swab specimen, if a pelvic examination is acceptable;
otherwise, a NAAT performed on urine.
 Culture performed on an endocervical swab specimen.
2010
 A nucleic acid amplification test (NAAT) performed on an
endocervical swab specimen, if a pelvic examination is acceptable
 Vaginal swabs are the optimal specimen type for use with NAATs
• Studies demonstrate equal performance to endocervical swabs and slightly
better performance than urine
• Ease of collection and transport
 Urine if vaginal swabs are not accepted by the patient
 Culture performed on an endocervical swab specimen when there is
a need to assess GC isolates for resistance to front line antibiotics

3. CT / GC Recommendations:
Infections of the Reproductive Tract (Male)
2002
 A nucleic acid amplification test (NAAT) performed on an
intraurethral swab specimen if collecting such a specimen is
acceptable; otherwise, a NAAT performed on urine.
 Culture performed on an intraurethral swab specimen
2010
 NAAT performed on urine
 Culture performed on an intraurethral swab specimen when there is
a need to assess GC isolates for resistance to front line antibiotics

4. CT / GC Recommendations:
Rectal and Pharyngeal Infections (CT)
2002
 Culture performed on rectal or pharyngeal swab specimens; a C.
trachomatis-major outer membrane protein (MOMP)-specific stain
should be used.
2010
 A nucleic acid amplification test (NAAT) performed on a rectal swab
• NAATs are not cleared for rectal specimens by the FDA
• CDC funded an external specimen bank to facilitate an off-label establishment
study
• Protocol and guidelines developed by the APHL/CDC STD Steering Committee
– www.aphl.org/aphlprograms/infectious/std/Documents/NAATRectalSwabs.p
df
– These are not prescriptive and must be reviewed by local CLIA surveyors
 Too few pharyngeal CT infections for a meaningful comparison

5. CT / GC Recommendations:
Rectal and Pharyngeal Infections (GC)
2002
 Culture performed on rectal or pharyngeal swab specimens; a
selective medium should be used with additional testing on colonies
of typical oxidase-positive, Gram-negative diplococci.
2010
 A nucleic acid amplification test (NAAT) performed on a rectal or
pharyngeal swab
• NAATs are not cleared for these specimen types by the FDA
• Some NAATs report cross-reaction and these may require repeat testing by an
alternative method
• CDC funded an external specimen bank to facilitate an off-label establishment
study
• Protocol and guidelines developed by the APHL/CDC STD Steering Committee
 Culture performed on rectal or pharyngeal swab specimens when
there is a need to assess GC isolates for resistance to front line
antibiotics

6. CT / GC Recommendations:
Supplemental Testing
2002
 An additional test should be considered after a positive screening
test if a false-positive screening test would result in substantial
adverse medical, social, or psychological impact for a patient.
 Consideration should be given to routinely performing an additional
test after a positive screening test if the positive predictive value is
considered low (e.g., <90%).
2010
 Routine repeat testing of NAAT positive specimens is not
recommended for CT
 Routine repeat testing of NAAT positive specimens is not
recommended for GC unless there are a significant number of false-
positive test results, in clinical studies, due to cross-reaction with
non-gonococcal Neisseria species

7. CT / GC Recommendations:
Testing Specimens Related to Possible Sexual Assault or
Abuse
2002
 Culture is the recommended method for detecting C. trachomatis
and N. gonorrhoeae in urogenital, pharyngeal, and rectal specimens
2010
 NAATs are the recommended method for detecting C. trachomatis
and N. gonorrhoeae in urogenital specimens
• Some NAATs report cross-reaction with non-gonococcal Neisseria species and
these may require repeat testing by an alternative method
 Limited data on the use of NAATs with pharyngeal and rectal
specimens from children