The looming tide of nontuberculous mycobacterial infections in Portugal and Brazil

Abstract

Nontuberculous mycobacteria (NTM) are widely disseminated in the environment and an emerging cause of infectious diseases worldwide. Their remarkable natural resistance to disinfectants and antibiotics and an ability to survive under low-nutrient conditions allows NTM to colonize and persist in man-made environments such as household and hospital water distribution systems. This overlap between human and NTM environments afforded new opportunities for human exposure, and for expression of their often neglected and underestimated pathogenic potential. Some risk factors predisposing to NTM disease have been identified and are mainly associated with immune fragilities of the human host. However, infections in apparently immunocompetent persons are also increasingly reported. The purpose of this review is to bring attention to this emerging health problem in Portugal and Brazil and to emphasize the urgent need for increased surveillance and more comprehensive epidemiological data in both countries, where such information is scarce and seriously thwarts the adoption of proper preventive strategies and therapeutic options.

HIV-negative pulmonary disease caused by nontuberculous mycobacteria in Southern Brazil: clinical and microbiological characterization

“…From 1991 to 1997 a study with 1,892 NTM isolates from 1,248 patients in the state of São Paulo, showed that MAC and M. kansasii were the most frequently species identified (12). Nunes-Costa et al (2016) reviewing the literature about NTM infections in Brazil and Portugal found that MAC was the most reported NTM in Brazilian studies (48%), followed by M. Kansasii (17%), M. fortuitum (7%), M. gordonae (6%), M. abscessus (5%) and M. chelonae (3%), quite similar to what is observed in Portugal (9). The findings of our study showed that M. intracellulare is the most frequent NTM isolated in pulmonary specimens from patients with confirmed NTM disease in Southern Brazil, followed by M. avium and M. abscessus.…”

“…Brazil is a continental country and NTM isolation rates are quite different among different regions, but there is a predominance of MAC, M. kansasii and M. fortuitum causing active NTM disease. Brazil is a high tuberculosis (TB) burden country and had for many years overshadowed the role of NTM in human disease (9,10).…”

Quantitative N-Terminal Footprinting of Pathogenic Mycobacteria Reveals Differential Protein Acetylation

“…21,22 In addition to mycobacterial species that cause TB, there are several nontuberculous mycobacteria (NTM) that are an emerging health threat. 23,24 Mycobacterium marinum is an NTM and an opportunistic human pathogen and an established model for studying M. tb pathogenesis. 25–29 A large-scale, shotgun proteogenomic approach aimed at improving genomic annotation reported NTA of proteins in the H37Rv laboratory strain of M. tb .…”

Mycobacterium avium paratuberculosis and Mycobacterium avium complex and related subspecies as causative agents of zoonotic and occupational diseases

“…pig's wild boars, elephants, horse (M. silvaticum), and dog(M. hominissuis;Escobar-Escamilla et al, 2014;Nunes-Costa, Alarico, Dalcolmo, Correia-Neves, & Empadinhas, 2016;Yong et al, 2011).Therefore, there is the possibility of incidence of zoonotic and occupational infections by these subspecies.4 | OTHER MAC SUBSPECIESOther subspecies of MAC based on 16s rRNA sequencing mostly include M. chimaera (or MAC-A serovar from human respiratory system), M. colombiense (from children lymph nodes), M. arosiense (or MAC-X serovar from systemic osteomyelitis of HIV-infected children), M. indicus pranii (MIP or Mw), M. vulneris (isolated from ulcers), M. xenopi, and M. lepraemurium which caused infections less common in humans. Because of nonoptimization of diagnostic methods, these subspecies are underestimated…”