Length of time to laboratory diagnosis of Mycobacterium tuberculosis infection: Comparison of in-house methods with reference laboratory results

Objectives: To audit the time taken to obtain laboratory confirmation of infection with Mycobacterium tuberculosis using in-house methods of polymerase chain reaction (PCR) and culture and referral to a reference laboratory. Methods: Retrospective collection of data from laboratory records covering a period of 1 year, Results: Median time to microbiological diagnosis of a new infection using the in-house services in addition to the reference laboratory was 22.0 days. Using reference laboratory results alone, median time to diagnosis would have been 61.5 days. Conclusions: Development of on-site laboratory facilities to identify Mycobacterium tuberculosis can reduce the time to its identification by almost two-thirds. (C) 1999 The British Infection Society.