Objective:The incidence of lung disease caused by nontuberculous mycobacteria (NTM) has been increasing worldwide. In Brazil, there are few studies about nontuberculous mycobacterial lung disease (NTMLD), and its prevalence is yet to be known. Our objective was to determine the specific etiology of the disease in the state of Rio Grande do Sul, Brazil, as well as the frequency and diversity of NTM species in our sample of patients. Methods:This is a retrospective analysis of the medical records of patients diagnosed with NTMLD treated in a referral center located in the city of Porto Alegre, Brazil, between 2003 and 2013. Results:Our sample comprised 100 patients. The most prevalent NTM species were Mycobacterium avium complex (MAC), in 35% of the cases; M. kansasii, in 17%; and M. abscessus, in 12%. A total of 85 patients had received previous treatment for tuberculosis. Associated conditions included structural abnormalities in the lungs, such as bronchiectasis, in 23% of the cases; COPD, in 17%; and immunosuppressive conditions, such as AIDS, in 24%. Conclusions:MAC and M. kansasii were the most prevalent species involved in NTMLD in the state, similarly to what occurs in other regions of Brazil. Data on regional epidemiology of NTMLD, its specific etiology, and associated conditions are essential to establish appropriate treatment, since each species requires specific regimens. Most patients with NTMLD had received previous tuberculosis treatment, which might lead to development of resistance and late diagnosis.

We conducted a cross-sectional, retrospective study, characterized by classical and molecular epidemiology, involving M. tuberculosis isolates from a regional prison in southern Brazil. Between January of 2011 and August of 2014, 379 prisoners underwent sputum smear microscopy and culture; 53 (13.9%) were diagnosed with active tuberculosis. Of those, 8 (22.9%) presented with isoniazid-resistant tuberculosis. Strain genotyping was carried out by 15-locus mycobacterial interspersed repetitive unit-variable-number tandem-repeat analysis; 68.6% of the patients were distributed into five clusters, and 87.5% of the resistant cases were in the same cluster. The frequency of drug-resistant tuberculosis cases and the rate of recent transmission were high. Our data suggest the need to implement an effective tuberculosis control program within the prison system.

Outbreaks associated with rapidly growing mycobacteria (RGM) have been increasingly reported worldwide, including in Brazil. Among the RGM, the Mycobacterium abscessus complex is the most pathogenic and related to multidrug resistance. The aim of this study was to evaluate the antimicrobial susceptibility and molecular profile of RGM isolates involved in new postsurgical infection outbreaks in Brazil since 2007. Of the 109 cases reported in the state of Rio Grande do Sul between 2007 and 2011, 43 (39 %) had confirmed mycobacterial growth in culture. Clinical isolates were obtained from biopsy specimens or abscess aspirates. PRA-hsp65 restriction pattern identified the isolates as M. abscessus type 2, and partial rpoB sequencing confirmed the identification as M. abscessus subsp. bolletii. All isolates were susceptible to amikacin and resistant to ciprofloxacin, doxycycline, sulfamethoxazole, moxifloxacin and tobramycin. Most isolates (72 %) were fully susceptible to cefoxitin but six isolates (14 %) were fully resistant to clarithromycin. The latter differed from the susceptibility profiles of the previously described BRA100 clone from other Brazilian regions. Nevertheless, pulsed-field gel electrophoresis analysis revealed that these isolates belonged to a single BRA100 clone. In conclusion, our study reports the persistence of an emergent single and highly resistant clone of M. abscessus subsp. bolletii for several years even after national implementation of infection control measures. The first outbreak of M. abscessus subsp. bolletii reported in Brazil occurred in 2004 and involved 68 patients who had

BACKGROUND Mycobacterium abscessus complex (MABC) includes species with high resistance rates among mycobacterial pathogens. In fact, MABC infections may not respond to clarithromycin treatment, which has historically been very effective against MABC infection. Molecular markers have been proposed to detect both acquired (rrl polymorphisms) and inducible (erm(41) polymorphisms) clarithromycin resistance in MABC isolates.OBJECTIVESThis study aimed to evaluate the susceptibility profile and molecular markers of clarithromycin resistance in MABC.METHODSThe clarithromycin susceptibility profile was determined by broth microdilution with reads on days 3, 5, 7 and 14. Mutations in the rrl and erm(41) genes were evaluated by polymerase chain reaction (PCR) using specific primers, followed by sequencing.FINDINGSA total of 14 M. abscessus subsp. abscessus isolates and 28 M. abscessus subsp. massiliense isolates were evaluated, and clarithromycin resistance was observed in all isolates for up to three days of incubation. None of the 42 isolates exhibited a point mutation in the rrl gene, while all the isolates had a T28 polymorphism in the erm(41) gene. Moreover, all 28 M. abscessus subsp. massiliense isolates had a deletion in the erm(41) gene.MAIN CONCLUSIONSWhile all the MABC isolates exhibited acquired clarithromycin resistance, no isolates exhibited a point mutation in the rrl gene in this study. The M. abscessus subsp. massiliense isolates demonstrated clarithromycin resistance, which is an uncommon phenotype. The molecular data for the rrl and erm(41) genes were not consistent with the phenotypic test results of clarithromycin susceptibility, indicating a lack of correlation between molecular clarithromycin resistance markers for both acquired and inducible resistance.