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Mycobacterium avium complex (MAC) is a heterogeneous group of species found in several environmental sources and that exhibit variable degrees of pathogenicity. Among the MAC members, Mycobacterium colombiense has been related to pulmonary disease and disseminated infection in HIV-infected patients in Colombia. Lymphadenopathy cases have also been reported. We have described a fatal case of M. colombiense pulmonary disease in a Brazilian patient without evidence of HIV infection or other known causes of immunosuppression., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Foodborne diseases are a public health problem worldwide. The consumption of contaminated raw milk has been recognized as a major cause of transmission of bovine tuberculosis to humans. Other mycobacteria that may be present in raw milk and may cause diseases are those belonging to the Mycobacterium avium complex. In this study, molecular biology tools were applied to investigate raw milk contamination with Mycobacterium spp. in family dairy farms from Rio Grande do Sul, southern Brazil. Furthermore, different variables related to the source of the milk, herd characteristics, and management were evaluated for their effect on milk contamination. Five hundred and two samples were analyzed, of which 354 were from the Northwest region (102 farms with samples from 93 bulk tanks and 261 animals) and 148 from the South region of the state (22 farms with samples from 23 bulk tanks and 125 animals). Among them, 10 (1.99%) and 7 (1.39%) were positive for Mycobacterium tuberculosis (9 confirmed as Mycobacterium bovis) and M. avium complexes, respectively. There was no difference in the frequencies of positive samples between the regions or the sample sources. Of the positive samples, 4 were collected from a bulk tank (1 positive for M. avium and 3 for M. tuberculosis). Moreover, 1 sample was positive concomitantly for M. tuberculosis and M. avium complexes. On risk analysis, no variable was associated with raw milk contamination by M. tuberculosis complex species. However, washing the udders of all animals and drying them with paper towels were weakly classified as risk factors for M. avium contamination. Positive samples were obtained from both animals and bulk tanks, which emphasizes the importance of tuberculosis control programs and provides evidence that milk monitoring can be used as a control practice. Moreover, the findings of this study reinforce the need for awareness of the problems of raw milk consumption among the general population.

This work comprises 9 pulmonary nontuberculous mycobateria isolates obtained from sputum of 4 different patients from Brazil. The sequencing and phylogenetic analysis allowed their accurate identification as Mycobacterium intracellulare. We report a mutation at position 453 creating a new HaeIII cutting site and, therefore, a new PRA-hsp65 M. intracellulare profile., (Copyright © 2014 Elsevier Inc. All rights reserved.)

To identify clinical and therapeutic features of pulmonary nontuberculous mycobacterial (PNTM) disease, we conducted a retrospective analysis of patients referred to the Brazilian reference center, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil, who received a diagnosis of PNTM during 1993–2011 with at least 1 respiratory culture positive for NTM. Associated conditions included bronchiectasis (21.8%), chronic obstructive pulmonary disease (20.7%), cardiovascular disease (15.5%), AIDS (9.8%), diabetes (9.8%), and hepatitis C (4.6%).Two patients had Hansen disease; 1 had Marfan syndrome. Four mycobacterial species comprised 85.6% of NTM infections: Mycobacterium kansasii, 59 cases (33.9%); M. avium complex, 53 (30.4%); M. abscessus, 23 (13.2%); and M. fortuitum, 14 (8.0%). A total of 42 (24.1%) cases were associated with rapidly growing mycobacteria. In countries with a high prevalence of tuberculosis, PNTM is likely misdiagnosed as tuberculosis, thus showing the need for improved capacity to diagnose mycobacterial disease as well as greater awareness of PNTM disease prevalence.

Objective: To identify nontuberculous mycobacteria (NTM) isolated from sterile sites in patients hospitalized between 2001 and 2006 at the Clementino Fraga Filho University Hospital, located in the city of Rio de Janeiro, Brazil., Methods: During the study period, 34 NTM isolates from sterile sites of 14 patients, most of whom were HIV-positive, were submitted to phenotypic identification and hsp65 PCR-restriction enzyme analysis (PRA)., Results: Most isolates were identified as Mycobacterium avium, followed by M. monacense, M. kansasii, and M. abscessus., Conclusions: The combination of PRA, a relatively simple and inexpensive method, with the evaluation of a few phenotypic characteristics can allow NTM to be accurately identified in the routine of clinical laboratories.

Objective: To study the incidence of nontuberculous mycobacteria and the range of species isolated between 1996 and 2005 at a regional branch of the Adolfo Lutz Institute-located in the city of São José do Rio Preto, Brazil-and to show the importance of laboratory testing., Methods: Mycobacteria were isolated from pulmonary and extrapulmonary specimens and identified through phenotyping and molecular methods (polymerase chain reaction-restriction enzyme analysis)., Results: We isolated 317 nontuberculous mycobacterium strains: Mycobacterium avium complex, 182 (57.4%); M. gordonae, 33 (10.4%); M. fortuitum, 25 (7.9%); M. chelonae, 8 (2.5%); M. terrae complex, 8(2.5%); M.kansasii, 7 (2.2%); and less frequent species, 54 (17%). During this period, 72 cases (33.3%) were characterized as mycobacteriosis, according to bacteriological criteria established by the American Thoracic Society in 2007. Of those 72 cases, 56 were attributed to M.avium complex. Of those 56, 29 (51.8%) were characterized as disseminated disease. Six cases were attributed to M. fortuitum, 3 to M. gordonae, 2 to M. chelonae, 1 to M. abscessus, 1 to M. kansasii, 1 to M. intracellulare, 1 to M. malmoense and 1 to Mycobacterium ssp., Conclusions: These results show the importance of the bacteriological diagnosis, since identification of the species enables early and appropriate treatment.

The use of highly active antiretroviral therapy (HAART) for the treatment of HIV infection has been associated with a marked reduction in the incidence of most opportunistic infections. From April 2001 to February 2002, 80 blood samples from patients who were suspected to have disseminated mycobacterial infection, presenting fever and (preferably) a CD4 T cell count < 100.0 cell/mL were investigated. Twelve (15%) of the 80 blood cultures were positive for mycobacteria, with Mycobacterium avium being identified in 7 (8.8%) samples and M. tuberculosis in 5 (6.2%). The TCD4+ count at the time of M. avium bacteremia ranged from 7 cells/microL (average of 48.5 cell/microL), while in M. tuberculosis bacteremia it ranged from 50.0 cells/microL (average of 80.0 cell/microL). The prevalence of M. avium bacteremia in our study follows the expected decline in opportunistic infections observed after the introduction of HAART; however, mycobacteremia by M. tuberculosis still indicates a high prevalence of tuberculosis infection in AIDS patients.

Objective: To collect data on non-tuberculous mycobacteria (NTM) isolated from clinical laboratories in different countries to establish: 1) whether the isolation of NTM was increasing, 2) which species were increasing, and 3) whether there was any pattern of geographical distribution., Design: In 1996, the Working Group of the Bacteriology and Immunology Section of the International Union Against Tuberculosis and Lung Disease contacted 50 laboratories in different countries for the necessary information., Results: The number of patients reported with NTM was 36099 from 14 countries. Mycobacterium avium complex, M. gordonae, M. xenopi, M. kansasii and M. fortuitum were the five species most frequently isolated. There was a significant upward trend for M. avium complex and M. xenopi. Pigmented mycobacteria predominated in Belgium, the Czech Republic and the Mediterranean coast of Spain. Non-chromogenic mycobacteria were found to be predominant in the area of the Atlantic coast of Brazil and in Turkey, the United Kingdom, Finland and Denmark., Conclusions: There was an increase in the number of NTM isolated from clinical samples of patients. Isolation of the most frequent species is constantly changing in most of the geographical areas, and newer species are emerging due to better diagnostic techniques to detect and identify NTM.

Objective: Evaluate the incidence of mycobacterial disease and the colonization of the respiratory and gastrointestinal tracts by Mycobacterium avium complex (MAC) bacteria in AIDS patients., Inclusion Criteria: HIV-positive individuals with at least one CD(4)(+) count < 100 cells/mm(3)., Exclusion Criteria: Mycobacterial disease and MAC prophylaxis. Stool, sputum, and blood cultures were prospectively obtained every month from September, 1997, to December, 1999. The incidence was calculated using Poisson regression. Survival was estimated by the Kaplan Meier method and the Cox proportional hazard model., Results: We followed-up 79 patients during a median period of 428 days. Blood cultures (n = 742) were negative for all mycobacteria. Positive cultures (25 samples) were obtained from non-sterile sites: Stools (19/703 specimens = 2.7%) and sputum (14/742 specimens = 1.9%). MAC was isolated in 7/703 stool samples (1%) and 1/32 sputum specimens (0.1%). The incidence of patient colonization with MAC was 0.09 /year (CI=0.05-0.18). CD4 counts in patients colonized with MAC were below 100 cells/mm(3) in only 2 out of 8 cases. Restoration of CD(4)(+) counts >100 cells/mm(3) (HR = 0.18; CI = 0.05-0.70) predicted a lower risk of death (P<0.05) but was not protective for MAC colonization (HR=0.52;CI =0.62-4.35, P=0.55)., Conclusion: The absence of DMAC infection in colonized individuals argues in favor of a HAART protective effect against; DMAC; however, restoration of CD(4) counts did not protect patients against MAC colonization.

This study was done to determine the occurrence of mycobacteria in the bloodstreams of patients with fever and advanced AIDS in a Brazilian hospital. We also verified the capability of an automated method for recovering these bacteria. During a period of 19 months, 254 patients with AIDS were evaluated. Blood cultures were generally submitted in pairs and drawn separately. Blood cultures were processed by the BACTEC 460TB System (Becton Dickinson Microbiology Systems, Sparks, MD), using the Bactec 13A media (Becton Dickinson Microbiology Systems, Sparks, MD). Of the 530 vials submitted, 77 (14.5%) from 41 (16%) patients were positive. Mycobacterium avium complex was recovered from 45 (58.4%) of the 77 positive vials, corresponding to 22 (53.6%) patients with positive blood cultures. The average time to detect Mycobacterium avium complex was 15 days. Mycobacterium tuberculosis was recovered from 26 (33.8%) of the 77 positive vials, corresponding to 15 (36.6%) patients with positive blood cultures, with an average detection time of 24 days. Other species of mycobacteria were recovered from 6 (7.8%) of the 77 vials, corresponding to 4 (9.8%) patients. M.avium complex was fairly prevalent (8.7%) in severely ill patients with AIDS in our hospital. M. tuberculosis was also an important (6.0%) agent of systemic bacterial infections in these patients. The rapid diagnosis of mycobacteremia was possible with the implementation of this automated technology.

Objective: Disseminated Mycobacterium avium infection is an emerging opportunistic disease among patients with acquired immunodeficiency syndrome (AIDS) in Brazil. The mode of transmission of M. avium in a developing country setting needs to be better characterized., Methods: Mycobacterium avium strain collections in São Paulo and Rio de Janeiro were analyzed according to the strains' IS1245 DNA gel electrophoretic migration patterns. Medical records of the patients from whom M. avium isolates were available were reviewed, and their demographic characteristics were stratified according to the isolates' IS1245 DNA fingerprint patterns., Results: Of 105 patients, 33 (31%) with M. avium isolated between 1990 and 1994 had strains having IS1245 patterns identical in patterns seen in isolates from two or more patients (designated as cluster pattern strains). Cluster pattern strains were isolated from 21 (39%) of 54 patients with disseminated infection (defined as infection due to M. avium isolated from a sterile site in an adult patient). Six of the cluster pattern strains were isolated only from sterile sites. In São Paulo, cluster pattern strains were significantly more likely to be isolated from patients with disseminated disease., Conclusions: These preliminary observations suggest that in large cities of Brazil, a high proportion (at least 39%) of disseminated M. avium infections in patients with AIDS results from a recent transmission. Some strains of M. avium may be more likely to cause disseminated disease than others after an infection.

Mycobacterium avium complex (MAC) is ubiquitous throughout the world. It is an opportunistic pathogen in AIDS patients but the number of cases in HIV negative patients is also increasing. The aim of this study was to determine whether patients were being infected with different MAC strains or whether one strain was dominant. DNA obtained from isolates in Brazil and England were compared using pulsed field gel electrophoresis (PFGE). Strains from 22 Brazilian patients clustered into 7 groups but 68/90 patients had a unique strain. In all patients, Brazilian and English, the same strain was isolated repeatedly over time, some over several years. This study shows that it is most likely that Man is infected from the environment and that one strain can survive without change for many years both in the environment and in Man.

The purpose of this study was to assess the distribution of Mycobacterium avium serovars isolated from AIDS patients in São Paulo and Rio de Janeiro. Ninety single site or multiple site isolates from 75 patients were examined. The most frequent serovars found were 8 (39.2%), 4 (21.4%) and 1 (10.7%). The frequency of mixed infections with serovar 8 or 4 was 37.8%. Among the 90 strains examined, M. intracellulare serovars (7 strains) and M. scrofulaceum (4 strains) were found in 11 isolates (12%) indicating that M. avium (88%) was the major opportunistic species in the M. avium complex isolates in Brazilian AIDS patients.

Mycobacterium avium complex (MAC) infection has not been reported as a major opportunistic infection among patients with AIDS in Latin America or Africa. In this study, 125 AIDS patients who had persistent fever, anemia, and leukopenia were examined among 2628 AIDS patients admitted to Instituto de Infectologia Emilio Ribas between May 1990 and April 1992. From the bone marrow aspirates of the 125 patients, MAC was isolated from 23 (18.4%) and Mycobacterium tuberculosis was isolated from 9 (7.2%). Between 1985 and 1990, only 11 MAC isolations among 60,000 cultures obtained from human immunodeficiency virus-seronegative patients were documented in São Paulo. Hence, the minimal estimated rate of MAC infection in AIDS patients in this city was 23/2628, or 0.88%. These findings suggest that MAC infection is an important opportunistic infection, especially among a subset of patients with AIDS in Brazil who have clinical characteristics and risk activities similar to those associated with MAC infections in North America and Europe.