One hundred sixty-six cases of primary immunodeficiency diseases (PID) (95 males, 71 females), diagnosed according to WHO criteria, have been registered at the Children's Hospital, University of São Paulo, Brazil. The following frequencies were found: predominantly humoral defects, 60.8% (n = 101); T cell defects, 4.9% (n = 8); combined ID, 9.6% (n = 16); phagocyte disorders, 18.7% (n = 31); and complement deficiencies, 6% (n = 10). IgA deficiency was the most frequent disorder (n = 60), followed by transient hypogammaglobulinemia (n = 14), chronic granulomatous disease (n = 14), and X-linked agammaglobulinemia (n = 9). In comparison to other (national) reports, we observed higher relative frequencies of phagocyte and complement deficiencies. Recurrent infections were the cause of death in 12.7%. Allergic symptoms were observed in 41%, mainly in IgA-deficient, hypogammaglobulinemic, or hyper-IgE patients, and autoimmune disorders in 5%, predominantly in IgA and complement deficiencies. Five patients suffered from BCG dissemination; two of them died. This is the first Brazilian report on PID over an observation time of 15 years.
PIP: Over a 15-year observation period (1981-96), 166 cases of primary immunodeficiency disease (PID) were registered at the Department of Pediatrics, University of Sao Paulo, Brazil. PID was diagnosed according to World Health Organization criteria and only children with well-established deficiencies were included. The following frequencies were noted by PID classification: predominantly humoral defects (60.8%), T cell defects (4.9%), combined immunodeficiency (9.6%), phagocyte disorders (18.7%), and complement deficiencies (6%). The male to female ratio was 1.3 to 1. Immunoglobin A deficiency was the most frequent disorder (60 cases), followed by transient hypogammaglobulinemia (14 cases), chronic granulomatous disease (14 cases), and X-linked agammaglobulinemia (9 cases). Allergic symptoms occurred in 41% of cases. During the observation period, 23 children (13.8%) died, primarily of recurrent infections. Although improved diagnostic facilities have facilitated the recognition of immunodeficient children, the true incidence is likely to be higher than that detected in this study. Increased international collaboration is urged to improve the early detection of PID.