Modern laboratory diagnosis of mycobacterial infections

This review summarises recent advances made in microscopic techniques (fluo rescence and peptide nucleic acids) and culture techniques (solid, liquid, radiometric, and non-radiometric systems) and in the development of rapid m ethods for the identification of mycobacterial cultures thigh performance l iquid chromatography, thin layer chromatography, RNA sequencing, and polyme rase chain reaction restriction enzyme assays). The role of molecular ampli fication systems in identifying Mycobacterium tuberculosis is described. Mo st methods record high specificity and sensitivity for smear positive sputu m but have variable sensitivity for sputum smear negative and extrapulmonar y specimens. Specimen quality ill affect the performance of these assays an d organisational delays, such as the batching of specimens, can reduce the time saved. In house assays can be as effective as commercial systems as lo ng as appropriate controls are used.