Infección por Mycobacterium scrofulaceum en un niño de las Islas Galápagos - Ecuador / Mycobacterium scrofulaceum infection in a pediatric patient from the Galapagos Islands - Ecuador

Resumen Mycobacterium scrofulaceum es una micobacteria atípica de crecimiento lento que tiene como reservorio el ambiente. De forma ocasional causa enfermedad en humanos. Se presenta el caso de un niño de 10 años de edad con fiebre de cuatro meses de evolución, adenopatías cervicales, torácicas, abdominales e inguinales bilaterales, exantema, dolor abdominal y vómitos; con evidencia concomitante de serología positiva para el VEB y cultivo de los ganglios inguinales izquierdos con crecimiento de M. scrofulaceum. Es la primera comunicación de una infección causada por esta micobacteria en Ecuador, y que particularmente se presentó con un patrón de resistencia inusual.

Mycobacterium scrofulaceum is a slow-growing atypical mycobacteria with a reservoir in the environmen, and occasionally it causes disease in humans. The case of a 10-year-old patient with fever of four months of evolution is presented. Symptoms include bilateral adenopathies of neck, thorax, abdomen and inguinal region, rash, abdominal pain and vomiting; in addition, a positive serology for EBV and a culture of the left inguinal ganglia with growth of M. scrofulaceum were evidenced. Thus, this is the first report of human infection caused by the aforementioned mycobacterium in Ecuador, which it was particularly manifested with an unusual pattern of resistance.

Characterization of Proinflammatory Responses and Innate Signaling Activation in Macrophages Infected with Mycobacterium scrofulaceum

Mycobacterium scrofulaceum is an environmental and slow-growing atypical mycobacterium. Emerging evidence suggests that M. scrofulaceum infection is associated with cervical lymphadenitis in children and pulmonary or systemic infections in immunocompromised adults. However, the nature of host innate immune responses to M. scrofulaceum remains unclear. In this study, we examined the innate immune responses in murine bone marrow-derived macrophages (BMDMs) infected with different M. scrofulaceum strains including ATCC type strains and two clinically isolated strains (rough and smooth types). All three strains resulted in the production of proinflammatory cytokines in BMDMs mediated through toll-like receptor-2 and the adaptor MyD88. Activation of MAPKs (extracellular signal-regulated kinase 1/2, and p38, and c-Jun N-terminal kinase) and nuclear receptor (NF)-kappaB together with intracellular reactive oxygen species generation were required for the expression of proinflammatory cytokines in BMDMs. In addition, the rough morphotypes of M. scrofulaceum clinical strains induced higher levels of proinflammatory cytokines, MAPK and NF-kappaB activation, and ROS production than other strains. When mice were infected with different M. scrofulaceum strains, those infected with the rough strain showed the greatest hepatosplenomegaly, granulomatous lesions, and immune cell infiltration in the lungs. Notably, the bacterial load was higher in mice infected with rough colonies than in mice infected with ATCC or smooth strains. Collectively, these data indicate that rough M. scrofulaceum induces higher inflammatory responses and virulence than ATCC or smooth strains.

Mycobacteriosis [Part 1]: Non-tuberculous mycobccteria

From the turn of the last century reports continued of the isolation of Non-tuberculous mycobacteria [NTM], and there is now evidence that diseases caused by such organisms are becoming increasingly recognized in many places worldwide occuring more frequently than M. tuberculosis, particularly in association with HIV/AIDS infection. Better diagnostic techniques with optimal sense of suspicion and revitalization of the National Tuberculosis Control Programmes [NTCP] are urgently required to overcome this problem globally

Characterization of mycobacterial species in clinically diagnosed cases of pulmonary tuberculosis and their HIV status.

A total of 75 clinically diagnosed and radiologically evident cases suggestive of pulmonary tuberculosis were selected for study. Sputum sample of each patient was screened for AFB by Ziehl Neelsen staining and culture. On examination 20 smears were found positive for AFB and 55 smears were negative by concentration method. A total of 23 samples were found to be culture positive and 52 were culture negative. Of these, 22 stains were identified as Mycobacterium tuberculosis, one was identified as M. Scrofulaceum. Of the 75 patients 3 were seropositive for HIV-I antibodies. Out of these 3, one was found to be smear and culture positive and was identified as M. scrofulaceum. Other two seropositive patients were smear and culture negative for AFB.

Water soluble palmitic acid in media for cultivation of leprosy derived psychrophilic mycobacteria from Mycobacterium leprae infected tissues

Cultivation trials for Mycobacterium leprae resulted in growth of Mycobacterium psychrophilum (L). Media were inoculated with host grown Mycobacterium leprae cells from armadillo tissues, Nu mice foot pads or human lepromata. Cultures were obtained in liquid and on semisolid multifactoria 1 media containing water soluble palmitic acid or its salts. Ammonium thioglycolate and Napalmitate served as carbon and energy sources. The water soluble palmitic acid remained in perfect solution following sterilization in the autoclave, thus easily accessible to the cells. The cyclodextrin-Fe complex served as a siderophore to grow the obtained leprosy derived psychrophilic cells. The leprosy derived cultures and subcultures grew opimally at+10 degrees Celssius but deteriorated rapidly at + 32 degrees Celsius, in the multifactorial media. No growth occurred in 7H9 media. Cultures were not identified for classification.

Protective response in guinea pigs exposed to Mycobacterium aviumintracellulare/M. scrofulaceum, BCG & south Indian isolates of M. tuberculosis.

The protective immunity resulting from exposure to nontuberculous mycobacteria (NTM), BCG and virulent mycobacteria in different sequences was studied in the guinea pig model employing strains prevalent in the south Indian BCG trial area and time kinetics to observe the immuno-modulation. The findings suggest that during the early course of challenge infection in guinea pigs there was no interference with the immunity due to BCG, by prior exposure to NTM. In the animals sensitised with M. avium intracellulare before immunisation, the challenge infection was localised and confined to the site of inoculation, and only a few organisms reached the spleen. However, at the later stages of the infection, as seen by the spleen viable counts at 12 wk, it appeared that the barrier at the localised site of infection may not be intact in the animals with prior exposure to NTM, and a few organisms disseminate to the spleen.

Micobacteriosis por mycobacterium scrofulaceum: reporte de 1 caso / Mycobacterium scrofulaceum mycobacteriosis: report on one 1 case

Se reporte 1 caso de 1 paciente de 71 años que presentó trastornos respiratorios por más de 11 años. La microscopia directa fue negativa en 4 esputos y finalmente el cultivo permitió en 5 ocasiones una cepa caracterizada bioquímicamente como mycobacterium scrofulaceum. El caso se correspondió con una micobacteriosis