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

Autoři: Jovilia Abong aff001;  Victoria Dalay aff001;  Ivor Langley aff002;  Ewan Tomeny aff002;  Danaida Marcelo aff001;  Victor Mendoza aff001;  Arvin Christian Aquino aff001;  Anna Marie Celina Garfin aff003;  Bertie Squire aff002;  Charles Yu aff001
Působiště autorů: Research Division, De La Salle Medical and Health Sciences Institute, Dasmariñas City, Cavite, Philippines aff001;  Collaboration for Applied Health Research & Delivery, Liverpool School of Tropical Medicine, Liverpool, United Kingdom aff002;  National TB Control Program, Department of Health, Manila, Metro Manila, Philippines aff003
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article
doi: 10.1371/journal.pone.0227093



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.


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.


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.


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).


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.

Klíčová slova:

Coughing – Diagnostic medicine – Medicine and health sciences – Philippines – Physicians – Sputum – Tuberculosis – Tuberculosis diagnosis and management


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Článek vyšel v časopise


2019 Číslo 12