The Molecular Diagnostics section of the Public Health Laboratory provides testing for Chlamydia trachomatis using Abbott LCX or Roche AMPLICOR PCR assays. GEN-PROBE PACE2 and Abbott LCX are assays used for detection of Neisseria gonorrhoeae.
Chlamydia trachomatis infections are now recognized as the leading cause of sexually transmitted diseases in the United States, where 3-4 million cases are reported per year. Gonorrhea is one of the most commonly reported sexually transmitted diseases in the United States with nearly 700,000 reported cases per year.
The AMPLICOR Chlamydia trachomatis test is a direct DNA probe test that utilizes a nucleic acid amplification called Polymerase Chain Reaction (PCR) and nucleic acid hybridization for the detection of Chlamydia trachomatis plasmid DNA in endocervical, urethral (male), and urine (male) samples. Female urine has been added to the list of acceptable specimens based on an in-house validation study using the Abbott LCX assay as the reference method. The Molecular Diagnostics Section receives on average 7500 specimens per month for PCR testing. The lower cost of the assay, compared to Abbott LCX, ease of specimen processing, and its capability to handle the high volume of specimens received by the laboratory has made PCR the primary diagnostic test used by the laboratory for detection of Chlamydia trachomatis.
The Molecular Diagnostics section receives on average 4500 specimens per month for detection of Neisseria gonorrhoeae and/or Chlamydia trachomatis, using the Abbott LCX assay. The assay uses the nucleic acid amplification method Ligase Chain Reaction (LCR) to detect the presence of the aforementioned organisms' DNA directly in clinical specimens. FDA has approved the use of female endocervical and male urethral swab specimens or male and female urine specimens from asymptomatic and symptomatic males and females in the assay. The assay enables us to detect the presence of both Neisseria gonorrhoeae and Chlamydia trachomatis in a single urine specimen.
The GEN-PROBE PACE2 System for Neisseria gonorrhoeae is a rapid DNA probe test that utilizes the technique of nucleic acid hybridization for the detection Neisseria gonorrhoeae in female endocervical and male urethral swab specimens and identification of Neisseria gonorrhoeae from culture isolates. Rectal and pharyngeal swab specimens have been added to the list of the acceptable specimens based on an in-house validation study using culture as the reference method. Currently, PACE2 is used primarily for detection of Neisseria gonorrhoeae in approximately 900 swab specimens, from non-genital sources, submitted per month to the laboratory. Since PACE2 has shown decreased sensitivity in swab samples relative to either LCR or culture, in a high prevalence population used for a comparison study of LCR, PACE2 and culture, we have made the decision not to use the assay as the primary diagnostic test for Neisseria gonorrhoeae.
||Chlamydia trachomatis, nucleic acid amplification, PCR
||Cervical or male urethral swab in M4 transport medium. Male 20-50 mL in urine in sterile container. Transport in cold pack.
||Neisseria gonorrhoeae, nucleic acid amplification, LCR
|| Cervical or male urethral swab in LCR swab specimen transport medium at ambient temperature. Urine: 15-20 mL first void in sterile container. Refrigerate immediately and transport in cold pack.