Nucleic acid tests for the diagnosis of sexually transmitted diseases

Nucleic acid (NA) assays have been developed and commercialized for many sexually transmitted diseases (STDs). Solid phase, liquid phase or in situ hybridization of nucleic acids without amplification procedures have been successfully used for diagnosing Chlamydia trachomatis, Neisseria gonorrhoeae and human papillomaviruses. Tests which use amplification procedures have provided better sensitivity and specificity than traditional tests. With special temperatures and enzymes, the new tests are designed to amplify either the target nucleic acid or the probe after annealing to the target. A third approach uses signal amplification. This article discusses the technology, specimen requirements and the current status of NA assay performance for diagnosing STDs and HIV by traditional and non-invasive clinical specimens.