TABLE 1.

Recommended diagnostic methods according to specimen type for Chlamydia trachomatis

	Diagnostic method
Specimen	Microscopy	Culture	AD*	NAH*	NAA†
Conjunctival	+	+	+	+	+
Nasopharyngeal	–	+	–	–	+
Cervical	–‡	+	+	+	+
Urethral	–	+	+	+	+
Rectal	–	+	+§	–	+
Vulval	–	–	–	–	+
Vaginal	–	–	–	–	+
Introital	–	–	–	–	+
Meatal	–	–	–	–	+
Urine	–	–	–	–	+
Bubo pus	–	+	–	–	+
Semen	–	–	–	–	+¶

^*Samples positive by nucleic acid hybridization (NAH) or enzyme immunoassay antigen detection (AD) require confirmation by another AD method or by neutralization;

^†Relative to the other assays, nucleic acid amplification (NAA) tests are the most sensitive and specific;

^‡Papanicolaou smear not useful;

^§Only direct fluorescent antibody;

^¶No commercial NAA tests are approved, therefore, semen should only be used with a validated protocol. Low-level NAA results are not always repeatable