Desempenho do GeneXpert MTB/RIF Ultra no Diagnóstico da Tuberculose em um Laboratório de Referência no Norte do Brasil

Abstract

Tuberculosis (TB), a disease caused by Mycobacterium tuberculosis, remains a major public health challenge. Its diagnosis continues to be a source of study and a fundamental part of controlling the disease. Objectives: To evaluate the performance of geneXpert MTB/Rif ultra versus conventional methods (bacilloscopy and culture) in the diagnosis of TB in a Central Public Health Laboratory (LACEN, Tocantins), northern Brazil. Methods: Retrospective study, with results of 263 suspected cases of TB from patients treated between January 2020 and December 2020 at LACEN-TO. Results: From the culture (reference standard), the sensitivity, specificity, PPV, NPV and accuracy of the geneXpert MTB/Rif ultra were 100%, 92%, 74%, 100% and 93%, respectively against 84%, 95%, 79%, 96% and 93% of bacilloscopy. When we evaluated its performance regarding the exception with negative bacilloscopy, the sensitivity, specificity, PPV, NPV and accuracy of the geneXpert MTB/Rif ultra were 100%, 96%, 48%, 100% and 96%. Conclusions: The geneXpert MTB/Rif ultra showed similar performance to culture and greater sensitivity than bacilloscopy, proving to be a valuable tool in the early detection of TB, even in paucibacillary patients. Furthermore, the high NPV demonstrated showed that this technique can be useful in excluding the disease in suspected patients.