Blocking antibody assay for confirmation of urogenital Chlamydia infection.
We evaluated the Syva MicroTrak Chlamydia Blocking Antibody Assay as a confirmatory assay for the detection of Chlamydia trachomatis in urogenital specimens. During a 5-month period, 109 positives were obtained (4.9%) by the MicroTrak II Enzyme Immunoassay as implemented with the Syva XL automated enzyme immunoassay instrument. Of 98 evaluable samples, 92 (93.9%) were confirmed as positive by the blocking assay, and 3 blocking-negative samples had organisms detected by direct fluorescent-antibody analysis (blocking sensitivity, 96.8%). We found that direct fluorescent-antibody analysis of samples with a specimen-to-cutoff absorbance ratio of < or = 2.0 was a reasonable confirmation alternative and was more cost-effective than the blocking assay.
Department of Pathology and Laboratory Medicine, University of Pennsylvania Medical Center, Philadelphia 19104-4283, USA.
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Nachamkin
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Riddle
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J
O'Connor
D000328:Adult; D000907:Antibodies, Bacterial / Q000737:chemistry*; D001666:Binding Sites, Antibody; D001667:Binding, Competitive / Q000276:immunology; D002690:Chlamydia Infections / Q000175:diagnosis* / Q000276:immunology / Q000382:microbiology; D002692:Chlamydia trachomatis / Q000276:immunology; D005260:Female; D052776:Female Urogenital Diseases / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D052801:Male Urogenital Diseases
D000907:Antibodies, Bacterial