Sputum induction for the diagnosis of pulmonary tuberculosis: a systematic review and meta-analysis
- 590 Downloads
Sputum induction (SI) has been proposed as the optimal sample collection method for patients with paucibacillary tuberculosis (TB). Studies reporting the culture of Mycobacterium tuberculosis from SI were reviewed. A random-effects meta-analysis of diagnostic yield (numerator M. tuberculosis SI culture-positive cases; denominator all culture-positive cases) was conducted. Diagnostic yields (95% confidence intervals, CIs) were displayed as Forest plots. Heterogeneity was evaluated using Chi-squared and I-squared tests and meta-regression analysis. Ninety publications were screened, 28 full-text papers reviewed, and 17 analyzed. Collectively, n = 627 SI culture-positive cases among n = 975 culture-confirmed TB cases were reported. The diagnostic yield of SI ranged from 35 to 95%. The pooled diagnostic yield was 74% (CI 65–81%), with significant heterogeneity (p < 0.0001, I2 = 86%). There were no statistically significant differences in the yield between sub-groups defined by human immunodeficiency virus (HIV) prevalence or age. Univariate analysis demonstrated that the use of fiberoptic bronchoscopy (FOB) as the comparator method was associated with a 22% reduction (CI 2–42%) in the diagnostic yield of SI. However, after adjustment for confounding, the meta-regression analysis showed that FOB usage (p = 0.21) and saline concentration (p = 0.31) were not independently associated with the diagnostic yield. SI will detect approximately three-quarters of M. tuberculosis culture-positive cases under study conditions. Significant heterogeneity in the diagnostic yield was not explained by HIV prevalence, age, or the use of FOB as the comparator method. The use of a particular nebulized saline concentration for SI cannot be recommended on the basis of this meta-regression analysis.
KeywordsHuman Immunodeficiency Virus Diagnostic Yield Human Immunodeficiency Virus Prevalence Gastric Lavage Fiberoptic Bronchoscopy
Y.G.-A. is the recipient of a SATVI Masters Scholarship and M.H. and W.H. are supported by a National Institutes of Health (NIH) grant (1R01AI075603-01).
Potential conflicts of interest
All authors: no conflicts.
- 1.World Health Organization (WHO) (2009) Global tuberculosis control—epidemiology, strategy, financing. WHO report 2009. WHO/HTM/TB/2009.411. WHO, Geneva, Switzerland. Available online at: http://www.who.int/tb/publications/global_report/2009/en/index.html
- 14.Conde MB, Soares SL, Mello FC, Rezende VM, Almeida LL, Reingold AL, Daley CL, Kritski AL (2000) Comparison of sputum induction with fiberoptic bronchoscopy in the diagnosis of tuberculosis: experience at an acquired immune deficiency syndrome reference center in Rio de Janeiro, Brazil. Am J Respir Crit Care Med 162(6):2238–2240PubMedGoogle Scholar
- 21.World Health Organization (WHO) (2000) Second generation surveillance for HIV: the next decade. WHO, Geneva, Switzerland. Available online at: http://www.who.int/reproductivehealth/publications/rtis/CDS_CSR_EDC_2000_5/en/index.html
- 26.Morse M, Kessler J, Albrecht S, Kim R, Thakur R, Nthobatsang R, Radisowa K, Maunatlala C, Yang W, Macgregor RR, Friedman H (2008) Induced sputum improves the diagnosis of pulmonary tuberculosis in hospitalized patients in Gaborone, Botswana. Int J Tuberc Lung Dis 12(11):1279–1285PubMedGoogle Scholar
- 33.Riso R, Mudido PM, Karamagi C, Whalen C (2005) The diagnosis of childhood tuberculosis in an HIV-endemic setting and the use of induced sputum. Int J Tuberc Lung Dis 9(7):716–726Google Scholar
- 36.Geldenhuys HD, Kleynhans W, Buckerfield N, Tameris M, Gonzalez Y, Mahomed H, Hussey G, Hanekom W, Hatherill M (2011) Safety and tolerability of sputum induction in adolescents and adults with suspected pulmonary tuberculosis. Eur J Clin Microbiol Infect Dis (in press)Google Scholar