Fluorescein diacetate and rapid molecular testing for the early identification of rifampicin resistance in Mali

• DOI: 10.5588/ijtld.19.0698
• Publication Date: 2020-09-11T04:47:38Z
• Authors: B. Diarra; T. Decroo; A. Somboro; G. Coulibaly; M. Tolofoudie; M. Kone; B. Degoga; F. Diallo; A. C. G. Togo; M. Sanogo; Y. S. Sarro; A. B. Cisse; O. Kodio; B. Baya; A. Kone; M. Maiga; S. Dao; I. I. Maiga; R. L. Murphy; S. Siddiqui; Y. Toloba; B. Konate; M. Diakite; S. Doumbia; A. Van Deun; L. Rigouts; S. Diallo; B. C. de Jong
• Keywords: 0303 health sciences; Sputum; Mycobacterium tuberculosis; Fluoresceins; Mali; Sensitivity and Specificity; 3. Good health; 03 medical and health sciences; Molecular Diagnostic Techniques; Drug Resistance, Bacterial; Tuberculosis, Multidrug-Resistant; Humans; Human medicine; Rifampin

BACKGROUND: Non-conversion on auramine smear microscopy indicates a lack of treatment response, possibly associated with initial rifampicin-resistant tuberculosis (RR-TB). However, dead bacteria still stain positive and may be detected. Fluorescein diacetate (FDA) shows live mycobacteria only. Therefore, we studied the potential 2-month (2M) FDA for identification RR-TB. METHODS: Between 2015 2018, enrolled new smear-positive pulmonary TB patients from five local centres in Bamako, Mali. After baseline screening, sputum samples were collected at 1M, 2M, 5M 18M. We used rpo B sequencing to identify RESULTS: Of 1359 enrolled, 1019 (75%) had results. Twenty-six (2.6%, 95%CI: 1.7–3.7) mutations conferring rifampicin resistance. Most frequent located codons Asp435Val (42.4%) Ser450Leu (34.7%). Among RR-TB, 72.2% FDA-negative 2M ( P = 0.2). The negative predictive value culture-based failure was respectively 20.0% 94.7%. CONCLUSION: did not majority RR-TB or failure. As full spectrum identified using Xpert, our data support its rapid universal implementation