High Mycobacterium tuberculosis Bacillary Loads Detected by Tuberculosis Molecular Bacterial Load Assay in Patient Stool: a Potential Alternative for Nonsputum Diagnosis and Treatment Response Monitoring of Tuberculosis
Emmanuel Musisi, Abdul Sessolo, Sylvia Kaswabuli, Josephine Zawedde, Patrick Byanyima, Shariifah Kasinga, Ingvar Sanyu, Esther Uwimaana, Stanley Walimbwa, Joseph Olore, Willy Ssengooba, Christine Sekaggya‐Wiltshire, Moses Joloba, William Worodria, Laurence Huang, Stephen H. Gillespie, Derek J. Sloan, Wilber Sabiiti
Abstract
This paper highlights the value of stool as a sample type for diagnosis of tuberculosis. While other studies have used DNA-based assays like the Xpert MTB/RIF and culture to detect Mycobacterium tuberculosis in stool, this is the first study that has applied TB-MBLA, an RNA-based assay, to quantify TB bacteria in stool. The high microbial density and diversity in stool compromises the specificity and sensitivity of culture-based tests due to overgrowth of non-M. tuberculosis flora. Consequently, TB-MBLA becomes the most sensitive and specific test for the detection and quantification of viable TB bacteria in stool. Most crucially, this study raises the possibility of a nonsputum alternative sample type for diagnosis of TB among people who have difficulty in producing sputum.