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.

Historia de la escrófula: de la discrasia humoral a la consunción / History of scrofula: from humoral dyscrasia to consumption

The term “scrofula” was used for a long time to designate a chronic swelling of cervical lymph nodes. This paper outlines the prevalent ideas on the nature, pathogenesis and the treatment of this disorder, from classical Greek medicine up to the 18th century. A Hippocratic treatise regarded scrofula as produced by an accumulation of phlegm, with a consequent imbalance or dyscrasia of the body humors. It was believed that it could heal spontaneously; but it could also soften, open through the skin and have an obstinate course. The treatment consisted mainly on local applications, incision to evacuate the soft content, or extirpation of the abnormal mass. In France and England, crowds of scrofulous patients were touched by the kings who were supposed to have a hereditary miraculous power to cure the disease. A Medieval text mentioned that scrofula could also affect other parts of the body. In the 17th century, scrofula was reputed as a frequent condition and was attributed to blood acrimony which coagulated in spongy organs. It was associated to phthisis or consumption due to the lethal outcome in some patients and to a cheese-like appearance of the pulmonary and the scrofulous lesions.

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.