S Ainan1,2, F F Furia1, F Mhimbira3,4, N P Mnyambwa2, N Mgina5, A Zumla6, S G Mfinanga2,4,7, E Ngadaya2. 1. Department of Paediatrics and Child Health, School of Medicine, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania. 2. National Institute for Medical Research, Muhimbili Medical Research Centre, Dar es Salaam, Tanzania. 3. Department of Intervention and Clinical Trials, Ifakara Health Institute, Dar es Salaam, Tanzania. 4. Department of Epidemiology and Biostatistics, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania. 5. Central Tuberculosis Reference Laboratory, Dar es salaam, Tanzania. 6. Department of Infection, Division of Infection and Immunity, University College London, and NIHR Biomedical Research Centre, University College London Hospitals NHS Foundation Trust, London, UK. 7. School of Life Sciences and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania.
Abstract
SETTING: Six health facilities in Dar es Salaam, Tanzania. OBJECTIVE: To evaluate the use of stool specimens in the diagnostic workup of paediatric TB using the Xpert® MTB/RIF assay. DESIGN: Between December 2018 and May 2019, we performed a cross-sectional diagnostic study of children aged between 1 month and 14 years with presumptive TB. A single stool specimen was tested using Xpert. The result was compared with the reference microbiological standard for respiratory or gastric specimens tested using Xpert and/or solid culture. The sensitivity, specificity and predictive values of stool Xpert assay were assessed. RESULTS: A total of 225 children with a median age of 2.17 years (IQR 1.16-5.19) were enrolled; 165/225 (73.3%) were aged <5 years. Of 225 children, 8 (3.6%) were diagnosed with TB as they were culture- or Xpert-positive on sputum/gastric aspirate. The stool Xpert assay showed a sensitivity of 62.5% (95% CI 25-92) and specificity of 100% (95% CI 98-100) against the reference standard. CONCLUSION: Use of the Xpert assay on stool specimens had a moderate sensitivity and high specificity in the diagnosis of pulmonary TB in children. Our data adds to the body of evidence for the use of Xpert assay on stool as a non-respiratory specimen to complement conventional methods used to diagnose the disease.
SETTING: Six health facilities in Dar es Salaam, Tanzania. OBJECTIVE: To evaluate the use of stool specimens in the diagnostic workup of paediatric TB using the Xpert® MTB/RIF assay. DESIGN: Between December 2018 and May 2019, we performed a cross-sectional diagnostic study of children aged between 1 month and 14 years with presumptive TB. A single stool specimen was tested using Xpert. The result was compared with the reference microbiological standard for respiratory or gastric specimens tested using Xpert and/or solid culture. The sensitivity, specificity and predictive values of stool Xpert assay were assessed. RESULTS: A total of 225 children with a median age of 2.17 years (IQR 1.16-5.19) were enrolled; 165/225 (73.3%) were aged <5 years. Of 225 children, 8 (3.6%) were diagnosed with TB as they were culture- or Xpert-positive on sputum/gastric aspirate. The stool Xpert assay showed a sensitivity of 62.5% (95% CI 25-92) and specificity of 100% (95% CI 98-100) against the reference standard. CONCLUSION: Use of the Xpert assay on stool specimens had a moderate sensitivity and high specificity in the diagnosis of pulmonary TB in children. Our data adds to the body of evidence for the use of Xpert assay on stool as a non-respiratory specimen to complement conventional methods used to diagnose the disease.
Authors: I Sabi; R Kabyemera; S E Mshana; B R Kidenya; G Kasanga; L E Gerwing-Adima; A Meremo; P Clowes; A Rachow; R N Peck Journal: Int J Tuberc Lung Dis Date: 2016-02 Impact factor: 2.373