Accuracy of serological tests for diagnosis of chronic pulmonary aspergillosis: A systematic review and meta-analysis.

Chronic pulmonary aspergillosis (CPA) is a slow and progressive disease that develops in preexisting lung cavities of patients with tuberculosis sequelae, and it is associated with a high mortality rate. Serological tests such as double agar gel immunodiffusion test (DID) or counterimmunoelectrophoresis (CIE) test have been routinely used for CPA diagnosis in the absence of positive cultures. However, these tests have been replaced with enzyme-linked immunoassay (ELISA) and, a variety of methods. This systematic review compares ELISA accuracy to reference test (DID and/or CIE) accuracy in CPA diagnosis. It was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The study was registered in PROSPERO under the registration number CRD42016046057. We searched the electronic databases MEDLINE (PubMed), EMBASE (Elsevier), LILACS (VHL), Cochrane library, and ISI Web of Science. Gray literature was researched using Google Scholar and conference abstracts. We included articles with patients or serum samples from patients with CPA who underwent two serological tests: ELISA (index test) and IDD and/or CIE (reference test). We used the test accuracy as a result. Original articles were considered without a restriction of date or language. The pooled sensitivity, specificity, and summary receiver operating characteristic curves were estimated. We included 14 studies in the review, but only four were included in the meta-analysis. The pooled sensitivities and specificities were 0.93 and 0.97 for the ELISA test. These values were 0.64 and 0.99 for the reference test (DID and/or CIE). Analyses of summary receiver operating characteristic curves yielded 0.99 for ELISA and 0.99 for the reference test (DID and/or CIE). Our meta-analysis suggests that the diagnostic accuracy of ELISA is greater than the reference tests (DID and/or CIE) for early CPA detection.

Tuberculosis infection among cocaine crack users in Brazil.

BACKGROUND: WHO recommends treatment for latent tuberculosis infection (LTBI) in the homeless and people who use drugs (PWUD). The optimal test for LTBI screening is uncertain. METHODS: A cross-sectional study was conducted among the homeless and drug-rehabilitation clinic clients chronically using crack in Western Brazil. Participants were interviewed and offered HIV testing plus tuberculin skin testing (TST) and QuantiFeron®-Gold-in-Tube (QFT). We considered LTBI when either TST or QFT were positive. Factors associated with LTBI were adjusted in a multivariate model. RESULTS: Among 372 subjects with at least one valid test, 216 (58%) had LTBI. TST was not read in 18.4%; QFT was indeterminate in 2.5%. TST detected 27 (26%) extra LTBI cases among 75 QFT-negative individuals. PWUD had over three-fold odds for LTBI. TST was 4.5 times more likely to be positive in BCG-vaccinated individuals. CONCLUSION: Given the high risk of progression to disease in this population, the high rates of loss to TST reading and the possibility of false-positive TST results from BCG vaccination, we endorse current CDC recommendations to use QFT for LTBI screening among the homeless and PWUD. However, because adding TST to a negative QFT increased LTBI detection considerably, TST should be considered in QFT-negative individuals.