e-Article
Rapid diagnosis of pulmonary tuberculosis in African children in a primary care setting by use of Xpert MTB/RIF on respiratory specimens: a prospective study.
Document Type
Academic Journal
Author
Zar HJ; Department of Paediatrics and Child Health, University of Cape Town, Cape Town, South Africa; Red Cross War Memorial Children's Hospital, Cape Town, South Africa. Electronic address: heather.zar@uct.ac.za.; Workman L; Department of Paediatrics and Child Health, University of Cape Town, Cape Town, South Africa; Red Cross War Memorial Children's Hospital, Cape Town, South Africa.; Isaacs W; Department of Paediatrics and Child Health, University of Cape Town, Cape Town, South Africa; Red Cross War Memorial Children's Hospital, Cape Town, South Africa.; Dheda K; Department of Medicine, University of Cape Town, Cape Town, South Africa.; Zemanay W; Division of Medical Microbiology, Institute for Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa; National Health Laboratory Service, Groote Schuur Hospital, Cape Town, South Africa.; Nicol MP; Division of Medical Microbiology, Institute for Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa; National Health Laboratory Service, Groote Schuur Hospital, Cape Town, South Africa.
Source
Publisher: Elsevier Ltd Country of Publication: England NLM ID: 101613665 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 2214-109X (Electronic) Linking ISSN: 2214109X NLM ISO Abbreviation: Lancet Glob Health Subsets: MEDLINE
Subject
Language
English
Abstract
Background: In children admitted to hospital, rapid, accurate diagnosis of pulmonary tuberculosis with the Xpert MTB/RIF assay is possible, but no paediatric studies have been done in the primary care setting, where most children are given care, and where microbiological diagnosis is rarely available. We assessed the diagnostic accuracy of Xpert MTB/RIF in children in primary care.
Methods: For this prospective study, we obtained repeat induced sputum and nasopharyngeal aspirate specimens from children (<15 years) with suspected pulmonary tuberculosis at a clinic in Khayeliwtsha, Cape Town, South Africa. We compared the diagnostic accuracy of Xpert MTB/RIF with a reference standard of culture and smear microscopy on induced sputum specimens. For the main analysis, specificity of Xpert MTB/RIF versus liquid culture, we included only children with two interpretable Xpert MTB/RIF and induced sputum culture results.
Findings: Between Aug 1, 2010, and July 30, 2012, we enrolled 384 children (median age 38·3 months, IQR 21·2-56·5) who had one paired induced sputum and nasopharyngeal specimen, 309 (81%) of whom had two paired specimens. Five children (1%) tested positive for tuberculosis by smear microscopy, 26 (7%) tested positive by Xpert MTB/RIF, and 30 (8%) tested positive by culture. Xpert MTB/RIF on two induced sputum specimens detected 16 of 28 culture-confirmed cases (sensitivity of 57·1%, 95% CI 39·1-73·5) and on two nasopharyngeal aspirates detected 11 of 28 culture-confirmed cases (sensitivity of 39·3, 23·6-57·6; p=0·18). The specificity of Xpert MTB/RIF on induced sputum was 98·9% (95% CI 96·9-99·6) and on nasopharyngeal aspirates was 99·3% (97·4-99·8).
Interpretation: Our findings suggest that Xpert MTB/RIF on respiratory secretions is a useful test for rapid diagnosis of paediatric pulmonary tuberculosis in primary care.
Funding: National Institutes of Health, National Health Laboratory Services Research Trust, the Medical Research Council of South Africa, the National Research Foundation South Africa, the European and Developing Countries Clinical Trials Partnership.
(Copyright © 2013 Zar et al. Open Access article distributed under the terms of CC BY. Published by .. All rights reserved.)
Methods: For this prospective study, we obtained repeat induced sputum and nasopharyngeal aspirate specimens from children (<15 years) with suspected pulmonary tuberculosis at a clinic in Khayeliwtsha, Cape Town, South Africa. We compared the diagnostic accuracy of Xpert MTB/RIF with a reference standard of culture and smear microscopy on induced sputum specimens. For the main analysis, specificity of Xpert MTB/RIF versus liquid culture, we included only children with two interpretable Xpert MTB/RIF and induced sputum culture results.
Findings: Between Aug 1, 2010, and July 30, 2012, we enrolled 384 children (median age 38·3 months, IQR 21·2-56·5) who had one paired induced sputum and nasopharyngeal specimen, 309 (81%) of whom had two paired specimens. Five children (1%) tested positive for tuberculosis by smear microscopy, 26 (7%) tested positive by Xpert MTB/RIF, and 30 (8%) tested positive by culture. Xpert MTB/RIF on two induced sputum specimens detected 16 of 28 culture-confirmed cases (sensitivity of 57·1%, 95% CI 39·1-73·5) and on two nasopharyngeal aspirates detected 11 of 28 culture-confirmed cases (sensitivity of 39·3, 23·6-57·6; p=0·18). The specificity of Xpert MTB/RIF on induced sputum was 98·9% (95% CI 96·9-99·6) and on nasopharyngeal aspirates was 99·3% (97·4-99·8).
Interpretation: Our findings suggest that Xpert MTB/RIF on respiratory secretions is a useful test for rapid diagnosis of paediatric pulmonary tuberculosis in primary care.
Funding: National Institutes of Health, National Health Laboratory Services Research Trust, the Medical Research Council of South Africa, the National Research Foundation South Africa, the European and Developing Countries Clinical Trials Partnership.
(Copyright © 2013 Zar et al. Open Access article distributed under the terms of CC BY. Published by .. All rights reserved.)