Use of GeneXpert and the role of an expert panel in improving clinical diagnosis of smear-negative tuberculosis cases.

SETTING:A high proportion of notified tuberculosis cases in the Philippines are clinically diagnosed (63%) as opposed to bacteriologically confirmed. Better understanding of this phenomenon is required to improve tuberculosis control. OBJECTIVES:To determine the percentage of smear negative presumpt...

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Bibliographic Details
Main Authors: Jovilia Abong, Victoria Dalay, Ivor Langley, Ewan Tomeny, Danaida Marcelo, Victor Mendoza, Arvin Christian Aquino, Anna Marie Celina Garfin, Bertie Squire, Charles Yu
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2019-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0227093
Description
Summary:SETTING:A high proportion of notified tuberculosis cases in the Philippines are clinically diagnosed (63%) as opposed to bacteriologically confirmed. Better understanding of this phenomenon is required to improve tuberculosis control. OBJECTIVES:To determine the percentage of smear negative presumptive tuberculosis patients that would be diagnosed by GeneXpert; compare clinical characteristics of patients diagnosed as tuberculosis cases; and review the impact that the current single government physician and a reconstituted Tuberculosis Diagnostic committee (expert panel) may have on tuberculosis over-diagnosis. DESIGN:This a cross-sectional study of 152 patients 15-85 years old with two negative Direct Sputum Smear Microscopy results, with abnormal chest X-ray who underwent GeneXpert testing and review by an expert panel. RESULTS:Thirty-two percent (48/152) of the sample were Xpert positive and 93% (97/104) of GeneXpert negatives were clinically diagnosed by a single physician. Typical symptoms and X-ray findings were higher in bacteriologically confirmed tuberculosis. When compared to the GeneXpert results the Expert panel's sensitivity for active tuberculosis was high (97.5%, 39/40), specificity was low (40.2%, 35/87). CONCLUSION:Using the GeneXpert would increase the level of bacteriologically confirmed tuberculosis substantially among presumptive tuberculosis. An expert panel will greatly reduce over-diagnosis usually seen when a decision is made by a single physician.
ISSN:1932-6203