: Chlamydia Antigen, Specimen, Qualitative

: What This Test Looks For

: The test detects antigens, which are protein markers belonging to the Chlamydia trachomatis bacterium. It is a qualitative test, meaning the report is generally positive (detected) or negative (not detected) rather than a measured amount.

: How the Sample Is Collected

: The specimen used depends on the testing method and your provider's instructions. Samples may come from urine or from a swab of the affected area such as the genital tract or, in some situations, the rectum or throat. Collecting the sample correctly is important for an accurate result.

: What Results Can Mean

: A positive result means Chlamydia antigen was detected and is generally treated as evidence of infection. A negative result does not always rule out infection; it can occur if the sample was inadequate, if the bacterial load was low, or if testing occurred too early after exposure.

: Screening and Follow-Up

: Because chlamydia often causes no symptoms, screening is recommended for people at increased risk. If the result is positive, the usual next steps include antibiotic treatment, avoidance of sexual contact until cleared, and evaluation and testing of partners to prevent reinfection.