title: Diagnostic Accuracy of the Small Membrane Filtration Method for Diagnosis of Pulmonary Tuberculosis in a High-HIV-Prevalence Setting.
abstract: Sputum acid-fast bacilli (AFB) smear microscopy has suboptimal sensitivity but remains the most commonly used laboratory test to diagnose pulmonary tuberculosis (TB). We prospectively evaluated the small membrane filtration (SMF) method that concentrates AFB in a smaller area to facilitate detection to improve the diagnostic performance of microscopy. We enrolled adults with suspicion of pulmonary TB from health facilities in southwestern Uganda. Clinical history, physical examination, and 3 sputum samples were obtained for direct fluorescent AFB smear, SMF, Xpert MTB/RIF, and MGIT culture media. Sensitivity and specificity were estimated for SMF, AFB smear, and Xpert MTB/RIF, using MGIT as the reference standard. The analysis was stratified according to HIV status. From September 2012 to April 2014, 737 participants were included in the HIV-infected stratum (146 [20.5%] were culture positive) and 313 were in the HIV-uninfected stratum (85 [28%] were culture positive). In HIV-infected patients, the sensitivity of a single SMF was 67.4% (95% confidence interval [CI], 59.9% to 74.1%); for AFB, 68.0% (95% CI, 60.6% to 74.6%); and for Xpert MTB/RIF, 91.0% (95% CI, 85.0% to 94.8%). In HIV-uninfected patients, the corresponding sensitivities were 72.5% (95% CI, 62.1% to 80.9%), 80.3% (95% CI, 70.8% to 87.2%), and 93.5% (95% CI, 85.7% to 97.2%). The specificity for all 3 tests in both HIV groups was ≥96%. In this setting, the SMF method did not improve the diagnostic accuracy of sputum AFB. The Xpert MTB/RIF assay performed well in both HIV-infected and -uninfected groups.
authors.affiliation: Epicentre, Médecins sans Frontières, Mbarara, Uganda.|Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda.
authors.forename: Yap
authors.initials: Y
authors.lastname: Boum
authors.affiliation: Department of Biostatistics, Rutgers School of Public Health, Rutgers, The State University of New Jersey, Newark, New Jersey, USA.
authors.forename: Soyeon
authors.initials: S
authors.lastname: Kim
authors.affiliation: Epicentre, Médecins sans Frontières, Mbarara, Uganda.|Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda.
authors.forename: Patrick
authors.initials: P
authors.lastname: Orikiriza
authors.affiliation: Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine, Boston, Massachusetts, USA.
authors.forename: Carlos
authors.initials: C
authors.lastname: Acuña-Villaorduña
authors.affiliation: Núcleo de Doenças Infecciosas (NDI), Universidade Federal do Espírito Santo (UFES), Vitória, Brazil.
authors.forename: Solange
authors.initials: S
authors.lastname: Vinhas
authors.affiliation: Epicentre, Médecins sans Frontières, Mbarara, Uganda.|Institut pour la Recherche et le Development (IRD) UMI 233 TransVIHMI-UM-INSERM U1175, Montpellier, France.
authors.forename: Maryline
authors.initials: M
authors.lastname: Bonnet
authors.affiliation: Epicentre, Médecins sans Frontières, Mbarara, Uganda.
authors.forename: Dan
authors.initials: D
authors.lastname: Nyehangane
authors.affiliation: Epicentre, Médecins sans Frontières, Mbarara, Uganda.|Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda.
authors.forename: Juliet
authors.initials: J
authors.lastname: Mwanga-Amumpaire
authors.affiliation: Division of Global Medicine, Department of Medicine, University of Florida at Gainesville, Gainesville, Florida, USA.
authors.forename: Kevin P
authors.initials: KP
authors.lastname: Fennelly
authors.affiliation: Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine, Boston, Massachusetts, USA edward.jones@bmc.org.
authors.forename: Edward C
authors.initials: EC
authors.lastname: Jones-López
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001431:Bacteriological Techniques / Q000379:methods*; D005260:Female; D005374:Filtration / Q000379:methods*; D015658:HIV Infections / Q000150:complications / Q000453:epidemiology; D006801:Humans; D008297:Male; D008853:Microscopy / Q000379:methods*; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D013183:Sputum / Q000382:microbiology*; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*; D014454:Uganda; D055815:Young Adult