Microbiological profile in chronic granulomatous disease patients in a single Brazilian primary immunodeficiency center.

BACKGROUND: Chronic granulomatous disease (CGD) is a rare primary immunodeficiency. Infections of lung, skin, lymph nodes, and liver are the hallmark of CGD and frequently the initial manifestation of the disease. The aim of the present paper is to describe the sites of infections and their causative agents in 38 pediatric patients with CGD. METHODS: This retrospective, single-center cohort study included CGD patients followed at the allergy and immunology unit of a tertiary hospital in São Paulo, Brazil over the last 40 years. Sites of infections and their causative agents were described. RESULTS: Thirty-eight patients were included (36 males). The median age of onset of symptoms was 45 days (ranging from 7 days-7 years), and the median age at diagnosis was 23 months (ranging from 1 month-12 years). In all, 31.6% of the patients reported a family history of child deaths and 21% (eight cases) had another male family member with CGD. The most common infections were pneumonia (81.6%), skin infections (50.0%), adenitis (42.1%), and liver abscess (23.7%); 188 cultures were positive (85.6% bacteria; 14.4% fungi). The most prevalent bacterial agents were Staphylococcus sp. (12.4%), Staphylococcus aureus (11.2%), and Klebsiella pneumoniae (9.3%). Aspergillus sp. and Candida sp. were 56% and 22.2% of the isolated fungi, respectively. Mycobacterium tuberculosis was isolated in 5.6% and Mycobacterium bovis in one patient (0.9%). CONCLUSION: Staphylococcus sp., Staphylococcus aureus, and Aspergillus sp. were the most frequent agents found in this cohort. M. tuberculosis should be considered in endemic area. Detection of infectious agents drives to the adequate treatment and benefits the evolution of patients with CGD.

[Provocation tests]. / Pruebas de provocación.

Oral provocation tests involve the supervised administration of suspected foods in increasing doses to evaluate a patient's allergic condition. Acknowledged as the superior method for diagnosing food allergies, it surpasses results from specific IgE serum or prick tests, which indicate sensitization but not necessarily allergy. The test is indicated in cases of diagnostic uncertainty, assessment of natural or induced tolerance, or cross-reactivity risks. Three types of tests exist: open, single-blind, and double-blind with a placebo. While the latter two reduce anxiety, open tests are more practical for children under three.

Las pruebas de provocación oral implican la administración supervisada de alimentos sospechosos en dosis crecientes para evaluar la condición alérgica del paciente. Reconocido como el mejor método para diagnosticar alergias alimentarias, supera los resultados de IgE sérica específica o pruebas de punción, que indican sensibilización pero no necesariamente alergia. La prueba se indica en casos de incertidumbre diagnóstica, evaluación de tolerancia natural o inducida, o riesgos de reacción cruzada. Existen tres tipos: abierta, simple ciega y doble ciega con placebo. Mientras que las dos últimas reducen la ansiedad, las pruebas abiertas son más prácticas para menores de tres años.