Subject(s)
Bacteremia/etiology , Pelvic Inflammatory Disease/complications , Peritonitis/complications , Streptococcal Infections/etiology , Streptococcus pyogenes , Acute Disease , Adult , Bacteremia/epidemiology , Canada/epidemiology , Female , Humans , Pelvic Inflammatory Disease/microbiology , Peritonitis/microbiology , Streptococcus pyogenes/isolation & purification , Vaginitis/complications , Vaginitis/microbiologyABSTRACT
Decision analysis methods were used to compare four mycobacteriology laboratory strategies with respect to time to confirmation and exclusion of smear-positive and smear-negative cases of pulmonary tuberculosis. Strategies assessed included the following: (i) polymerase chain reaction (PCR) on all respiratory specimens; (ii) PCR on smear-positive specimens and on the broth of vials for other specimens attaining a growth index >10 in a radiometric culture detection system; (iii) PCR on smear-positive specimens only; and (iv) radiometric culture detection, with DNA probe for species identification of vials attaining a growth index >999. Strategies i and ii had predicted average times to confirm cases of 5 and 7.6 days, respectively, and remained within 3 days of each other over a broad range of PCR performance with smear-negative specimens. In contrast, case-confirmation times using strategies iii and iv were 10.4 and 15.3 days, respectively. Only 10% of specimens were processed by PCR in strategy ii. Times to confirm smear-negative cases were comparable for strategies i and ii when PCR sensitivity was <40% with these specimens. Times to exclude pulmonary tuberculosis were similar for all strategies. Given the current suboptimal performance of PCR with smear-negative specimens, strategy ii offers accelerated case confirmation with limited PCR usage.