What is the common method for confirmation of Chlamydia trachomatis in sexually transmitted infections?

• A. Cell culture
• B. Nonculture EIA methods
• C. DNA-amplification techniques
• D. Culture on modified Thayer-Martin agar

Answer: (C)

Detecting Chlamydia trachomatis is most reliably done by DNA-amplification techniques because the organism is an intracellular bacterium and traditional culture can be difficult, slow, and requires specialized cell culture facilities. DNA-based tests, such as PCR or other nucleic acid amplification methods, target organism-specific genetic material, so they don’t depend on recovering live bacteria and they deliver rapid, highly sensitive and specific results. This makes them the preferred method for confirming infection, and they work well on noninvasive samples like urine or swabs.

Nonculture antigen tests can miss infections (lower sensitivity) and culture on specialized media or cells (like modified Thayer-Martin agar) is impractical for routine confirmation and is not routinely used for Chlamydia.