Función del sistema NADPH oxidasa en la formación de trampas extracelulares de los neutrófilos (NETs) / Role of nadph oxidase system in the neutrophil extracelular Traps (NETs) formation

Las trampas extracelulares de los neutrófilos son estructuras fundamentalmente compuestas de cromatina y proteínas granulares, que una vez liberadas constituyen un mecanismo de defensa que tiene la capacidad de atrapar y destruir microorganismos patógenos. El proceso que libera estas estructuras es conocido como NETosis y en el caso que provoque muerte celular, esta es diferente a la apoptosis y a la necrosis. Si bien no se conocen todos los eventos moleculares involucrados en la formación de las NETs, se sabe que dependiendo del estímulo, las especies reactivas del oxígeno son esenciales para que ocurra la descondensación de la cromatina y se lleve a cabo el proceso de NETosis(AU)

Neutrophil extracellular traps (NETs) are structures mainly composed of chromatin and granule proteins that once released constitute a defense mechanism due to their ability to trap and destroy pathogen microorganisms. The process by which these structures are released is known as NETosis and in case this may lead to cell death is different to apoptosis and necrosis. Although all the molecular events involved in the formation of NETs are poorly understood, it is known that depending on the stimulus, reactive oxygen species (ROS) are essential to the chromatin decondensation and subsequent NETs formation(AU)

Enfermedad granulomatosa crónica / Chronic granulomatous disease

La enfermedad granulomatosa crónica (EGC) es una inmunodeficiencia primaria de la fagocitosis. Se presenta un paciente de 13 años de edad que a partir el mes de nacido presentó infecciones recurrentes: diarreas, neumonías, tuberculosis pulmonar, gingivo-estomatitis, celulitis, adenitis, abscesos cutáneos y hepáticos recidivantes. Al examen físico presentó una disminución severa del peso y la talla para la edad, palidez cutáneo-mucosa, periodontitis crónica, hiperlaxitud, aumento del hemiabdomen derecho y adenopatías generalizadas. Los estudios inmunológicos mostraron concentraciones normales de las inmunoglobulinas (Ig) séricas IgM: 0,98 g/L (0,69 - 2,69 g/L), IgA: 2,76 g/L (1,58 - 3,94 g/L) e IgE: 11,70 UI/ml (hasta 50 UI/mL), respectivamente, y ligeramente aumentadas de IgG: 17,2 g/L (7,81 - 15,30 g/L), C3 y C4 normales: 1,28 g/L (0,9 - 1,7 g/L) y 0,30 g/L (0,2 - 0,4 g/L), respectivamente. Las subpoblaciones linfocitarias T CD3, CD4 y CD8 positivas estuvieron normales: 62 por ciento (52 - 78 por ciento), 45 por ciento (25 - 48 por ciento) y 15 por ciento (9 - 35 por ciento), y los linfocitos B CD19 positivos estuvieron normales: 24 por ciento (8 - 24 por ciento). El índice opsonofagocítico mostró valores normales en los tiempos 15 y 60 min: 35 por ciento (22,99 - 53,95 por ciento) y 12,50 por ciento (6,63 - 28,4 3 por ciento). La prueba de reducción de nitroazul de tetrazolium espontánea y con agente inductor (Cándida albicans) fue negativa. Se concluyó como una EGC ligada al cromosoma X. El tratamiento incluyó el drenaje de los abscesos hepáticos recidivantes, uso de antimicrobianos y antimicóticos potentes e interferón gamma, con lo que disminuyó la frecuencia e intensidad de las infecciones. El diagnóstico y el tratamiento precoces de la EGC disminuyen la morbilidad y mortalidad de estos enfermos...

Chronic granulomatous disease (CGD) is a primary immunodeficiency with a defect of the phagocytosis process. A 13 year-old adolescent with recurrent life-threatening episodes since one month of birth is presented. The main clinical manifestations included diarrhea, stomatitis, cellulitis, lymphadenitis, pneumonia, granuloma formation, pulmonary tuberculosis, pulmonary and hepatic abscesses. Physical examination showed poor growth, hepatomegaly, adenopathies, hyperextension of extremities and chronic gingivitis. Immunological studies showed normal concentrations of immunoglobulins (Ig): IgM: 0,98 g/L (0,69 - 2,69 g/L), IgA: 2,76 g/L (1,58 - 3,94 g/L) and IgE: 11,70 UI/mL ( < 50 UI/ml), C3 and C4 (1,28 g/L (0,9 - 1,7 g/L) and 0,30 g/L (0,2 - 0,4 g/L), respectively, and hypergammaglobulinemia of 17,2 g/L (7,81 - 15,30 g/L). Lymphocytes count T CD3, CD4 and CD8 positive were normal: 62 percent (52 - 78 percent), 45 percent (25 - 48 percent) y 15 percent (9 - 35 percent) and B lymphocytes count was also normal: 24 percent (8 - 24 percent). Opsonophagocytic index was normal at time 15 and 60 minutes: 35 percent (22,99 - 53,95 percent) and 12,50 percent (6,63 - 28,43 percent), respectively. Diagnosis was confirmed with negative nitroblue tetrazolium test . Treatment with antibiotics, fungistats, as well as gamma interferon contributed to a favorable response, presenting a lower amount of infectious episodes as well as a recovery of weight and height. Early diagnosis and treatment of CGD has improved prognosis and reduced patients´ morbidity and mortality...

Doença granulomatosa crônica: diagnóstico no primeiro episódio infeccioso / Chronic granulomatous disease: diagnosis on the first infection episode

OBJETIVO: Relatar caso ilustrativo de doença granulomatosa crônica cujo diagnóstico ocorreu durante o aparecimento do primeiro episódio infeccioso, colaborando com a iniciativa do Brazilian Group for Immunodeficiency para a sensibilização do pediatra geral em relação ao diagnóstico precoce das imunodeficiências primárias, o que está associado a melhor qualidade de vida e maior sobrevida desses indivíduos. DESCRIÇÃO DE CASO: Paciente do sexo masculino, 39 dias de vida, admitido em pronto-socorro pediátrico por febre alta há cinco dias e irritabilidade. No dia seguinte, observou-se abscesso cervical, isolando-se Staphylococcus aureus comunitário. Durante a internação, ocorreram outros abscessos superficiais e em cadeias ganglionares profundas, além de resposta lenta aos antimicrobianos. Solicitou-se investigação para imunodeficiências, que confirmou a hipótese de doença granulomatosa crônica por quantificação dos ânions superóxido e teste de redução do nitrobluetetrazolio. Paciente foi encaminhado a serviço especializado, no qual identificou-se doador de medula óssea compatível, realizando-se o transplante seis meses após o diagnóstico. Quatro meses após o transplante, ocorreu normalização do burst oxidativo, indicando sucesso. COMENTÁRIOS: O paciente mostrou apresentação típica da doença, o que permitiu seu diagnóstico por pediatras gerais já na primeira infecção, tendo como consequência o acompanhamento por especialistas em imunodeficiências primárias, a introdução da profilaxia antimicrobiana e a procura bem sucedida de doador de medula HLA-compatível.

OBJECTIVE: To report a case of chronic granulomatous disease diagnosed during the first infectious episode in order to collaborate with the Brazilian Group for Immunodeficiency, in sensitizing the general pediatrician that the early diagnosis of primary immunodeficiency results in better quality of life and longer life expectancy for the patients. CASE DESCRIPTION: Male patient, 39 days, admitted to the pediatric emergency ward with fever for the last five days and irritability. On the following day, a cervical abscess was noted and a community Staphylococcus aureus was isolated. During hospital stay, other abscesses were observed in the skin and in the deep ganglia chains, with a slow response to antibiotics. Investigation of immunodeficiency was requested and chronic granulomatous disease was confirmed by quantification of superoxide anions and nitrobluetetrazolium tests. The patient was transferred to a specialized clinic for bone marrow transplantation, performed six months after diagnosis. Four months afterwards, the normalization of oxidative burst was noted, indecating the success of the transplantation. COMMENTS: The patient showed a typical presentation of the disease, which allowed its diagnosis by general pediatricians on the first infection, allowing the follow-up by experts in primary immunodeficiencies, the introduction of antimicrobial chemoprophylaxis, and the successful search for an HLA-compatible bone marrow donor.

Effect of corticosteroid therapy in esophageal stricture of a child with chronic granulomatous disease

In chronic granulomatous disease [CGD] patients, esophageal stricture is a rare complication and the treatment of choice is still controversial. There are few reports of successful therapy with antibiotics, corticosteroids, multiple balloon dilatations or their combination. We report a 3-three-year-old Iranian boy with recurrent esophageal obstruction due to CGD. The patient transiently responded to dilatation in one occasion and at another time to short term steroid therapy. We observed an excellent response when long term and high dose of corticosteroid was administered. It showed that a long term and high dose steroid therapy is more effective than a short term in a patient with CGD and esophageal stricture

Enfermedad granulomatosa crónica: aspectos actuales / Chronic granulomatous disease: current aspects

La enfermedad granulomatosa crónica (EGC) es una inmunodeficiencia primaria causada por mutaciones en los genes que codifican para cualquiera de las 4 subunidades que conforman a la enzima adenina dinucleótido fosfato oxidasa (NADPH oxidasa), encargada de regular la producción de especies oxidantes microbicidas que constituyen la primera vía de defensa del organismo contra los microorganismos infecciosos. Esta es una deficiencia muy heterogénea clasificada en EGC ligada al cromosoma X (subunidad gp91-phox) y autosómica recesiva, donde puede estar afectada cualquiera de las siguientes subunidades de la enzima: p22-phox, p47-phox y p67-phox. Dentro de los hallazgos clínicos más frecuentes se encuentran entre otros la linfadenopatía, hepatoesplenomegalia, neumonía. Para el tratamiento de la enfermedad se utilizan antibióticos de amplio espectro y el interferón gamma para el tratamiento de infecciones severas en la EGC ligada al cromosoma X. Actualmente se están realizando estudios para utilizar la terapia génica somática como posible cura de la enfermedad