title: Sputum induction for the diagnosis of pulmonary tuberculosis: a systematic review and meta-analysis.
abstract: 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.
authors.affiliation: South African Tuberculosis Vaccine Initiative (SATVI), Wernher Beit Building N2.10, Faculty of Health Sciences, University of Cape Town, Anzio Road, Observatory, Cape Town, 7925, South Africa.
authors.forename: Y
authors.initials: Y
authors.lastname: Gonzalez-Angulo
authors.forename: C S
authors.initials: CS
authors.lastname: Wiysonge
authors.forename: H
authors.initials: H
authors.lastname: Geldenhuys
authors.forename: W
authors.initials: W
authors.lastname: Hanekom
authors.forename: H
authors.initials: H
authors.lastname: Mahomed
authors.forename: G
authors.initials: G
authors.lastname: Hussey
authors.forename: M
authors.initials: M
authors.lastname: Hatherill
mesh_terms: D001431:Bacteriological Techniques / Q000379:methods*; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology*; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*
references.citation: Lancet. 2005 Jan 8-14;365(9454):130-4
references.pmid: 15639294
references.citation: Lancet. 2005 Jan 8-14;365(9454):150-2
references.pmid: 15639297
references.citation: Eur Respir J Suppl. 2002 Sep;37:51s-55s
references.pmid: 12361365
references.citation: Bull World Health Organ. 1998;76(6):651-62
references.pmid: 10191561
references.citation: Am J Respir Crit Care Med. 2007 Jan 1;175(1):80-6
references.pmid: 17053204
references.citation: Tubercle. 1989 Jun;70(2):151-2
references.pmid: 2515646
references.citation: Br Med J (Clin Res Ed). 1981 Nov 14;283(6302):1285-7
references.pmid: 6794821
references.citation: Respirology. 2009 Aug;14(6):899-902
references.pmid: 19659832
references.citation: Dis Chest. 1961 Dec;40:639-42
references.pmid: 13906568
references.citation: Clin Infect Dis. 2007 Jun 1;44(11):1415-20
references.pmid: 17479935
references.citation: Lung. 1990;168(4):215-20
references.pmid: 2122138
references.citation: Kekkaku. 1996 Nov;71(11):603-6
references.pmid: 8958672
references.citation: Dis Chest. 1967 Jun;51(6):614-20
references.pmid: 6027030
references.citation: Int J Tuberc Lung Dis. 2005 Jul;9(7):716-26
references.pmid: 16013765
references.citation: Am Rev Respir Dis. 1963 Aug;88:223-7
references.pmid: 14045227
references.citation: Int J Tuberc Lung Dis. 2001 Sep;5(9):855-60
references.pmid: 11573898
references.citation: Arch Dis Child. 2007 Aug;92(8):693-6
references.pmid: 17185437
references.citation: Eur J Clin Microbiol Infect Dis. 2012 Apr;31(4):529-37
references.pmid: 21796347
references.citation: Dis Chest. 1962 Jul;42:74-8
references.pmid: 13866265
references.citation: J Clin Invest. 1997 Jan 1;99(1):9-13
references.pmid: 9011581
references.citation: Int J Tuberc Lung Dis. 2009 Jan;13(1):99-104
references.pmid: 19105886
references.citation: Arch Dis Child. 2000 Apr;82(4):305-8
references.pmid: 10735837
references.citation: Int J Tuberc Lung Dis. 2008 Nov;12(11):1279-85
references.pmid: 18926038
references.citation: Clin Infect Dis. 2006 Apr 15;42(8):e69-71
references.pmid: 16575719
references.citation: Clin Infect Dis. 2003 Dec 15;37(12):1649-53
references.pmid: 14689347
references.citation: Am J Respir Crit Care Med. 2000 Dec;162(6):2238-40
references.pmid: 11112145
references.citation: Arch Dis Child. 2009 Mar;94(3):195-201
references.pmid: 18829621
references.citation: Eur Respir J Suppl. 2002 Sep;37:9s-18s
references.pmid: 12361366
references.citation: Mymensingh Med J. 2008 Jul;17(2):115-23
references.pmid: 18626443
references.citation: Dis Chest. 1966 Oct;50(4):403-8
references.pmid: 4958938
references.citation: Eur Respir J Suppl. 2002 Sep;37:1s-2s
references.pmid: 12361359
references.citation: Am J Respir Crit Care Med. 1995 Nov;152(5 Pt 1):1570-4
references.pmid: 7582296
references.citation: Sao Paulo Med J. 2003 Sep 1;121(5):213-9
references.pmid: 14666295
references.citation: Thorax. 2002 Dec;57(12):1010-4
references.pmid: 12454293
references.citation: BMJ. 2003 Sep 6;327(7414):557-60
references.pmid: 12958120