Laboratory testing for Chlamydia trachomatis in New Zealand

Purpose: To assess clinician knowledge of laboratory tests used to diagnose genital chlamydia infection and to determine the availability and type of diagnostic tests used by clinical Laboratories. Methods: Sexual health, family planning and student and youth health clinic s and randomly selected general practitioners (GPs) were surveyed in Novemb er 1997 regarding knowledge of tests used to diagnose chlamydia. Diagnostic laboratories were surveyed regarding tests used and the number of specimen s tested. Results: Half (52 per cent) of GPs and 30 per cent. 26 per cent and 11 per cent of student and youth health, family planning and sexual health clinic staff respectively did not know which tests their laboratory used to diagno se chlamydia. Of the 40 laboratories that tested for chlamydia. 58 per cent used enzyme immunoassay (EIA). 73 per cent direct fluorescent antibody (DF A), and 20 per cent nucleic acid (DNA) amplification tests. By April 2000, 43 per cent of laboratories performed DNA amplification tests, Approximatel y 62 per cent of specimens sent for testing were from GPs. The proportion o f specimens positive for chlamydia was 4.2 per cent in women and 8.3 per ce nt in men, 4.6 per cent total. Of the positive specimens, 78.6 per cent wer e from women. Conclusions: Many New Zealand clinicians were unable to identify the tests used by their laboratory to diagnose chlamydia. Clinicians need io consider the test methodology when deciding when to test for chlamydia and how to i nterpret test results.