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BIBTEX RIS

First insights into circulating XDR and pre-XDR Mycobacterium tuberculosis in Southern Brazil

2019; Elsevier BV; Volume: 78; Linguagem: Inglês

10.1016/j.meegid.2019.104127

ISSN

1567-7257

Autores

Richard Steiner Salvato, Elis Regina Dalla Costa, Ana Júlia Reis, Sun Hee Schiefelbein, Maria Laura Halon, Regina Bones Barcellos, Gisela Unis, Cláudia Fontoura Dias, Miguel Viveiros, Isabel Portugal, Pedro Eduardo Almeida da Silva, Afrânio Lineu Kritski, João Perdigão, Maria Lúcia Rosa Rossetti,

Tópico(s)

Antibiotic Resistance in Bacteria

Resumo

Drug-resistant tuberculosis (DR-TB) is major problem in the fight against TB. Multidrug resistant (MDR) TB patients have a reduced treatment success rates and for, extensively drug-resistant (XDR) TB the cure rate does not exceed 25% in many countries. To evaluate the pre-XDR-TB and XDR-TB prevalence and transmission in Rio Grande do Sul State, in southern Brazil, we performed a retrospective WGS-based analysis of 87 MDR-TB cases, aiming to identify resistance-conferring mutations and its phylogenetic distinctiveness. Using a five SNP threshold for genomic clustering, 60 strains were genomically linked within 10 clusters, including 14 likely transmission events identified by retrospective conventional epidemiological investigation. Moreover, five likely transmission events involved 17 patients deprived of liberty in the same prison establishment. Mutations associated with isoniazid and rifampicin resistance were identified respectively in 97.70% and 98.85% of MDR M.tb strains, more frequently in katG and rpoB genes. In total, we identified eight (9.19%) pre-XDR and four (4.59%) XDR M.tb strains. Resistance to ofloxacin was observed in seven (8.04%) strains, all of them presenting resistance-conferring mutations. Phenotypic resistance from capreomycin and kanamycin was found in seven (8.04%) and four (4.59%) strains respectively, but no classic mutations associated with resistance to these drugs was identified. The results put in evidence a scenario involving multiple phylogenetically distinctive clades associated with pre-XDR and XDR-TB in the largest state of southern Brazil, while stressing the potential of using WGS to predict anti-TB drug resistance and need to halt MDR-TB transmission in the region.

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