Barata, LTHenriques, RHivroz, CJouanguy, EPaiva, AFreitas, AMCoimbra, HBFischer, ACarmona da Mota, H2011-10-242011-10-242001Acta Med Port. 2001 Jul-Aug;14(4):413-7.http://hdl.handle.net/10400.4/1089The authors present the case of a child with recurrent infections since the age of 4 months, including bilateral pneumonia by Pneumocystis carinii and protracted varicella. Serum immunoglobulin values (when 10 months old), and B cell values were normal. There was persistent lymphocytic leucocytosis, near absence of CD8+ cells, and an increased CD4/CD8 ratio. The percentage of activated T cells and the expression of HLA class I were normal. Proliferation, activation and IL-2 synthesis studies in T cells showed a TCR/CD3-associated signal transduction deficit. ZAP-70 cDNA sequencing showed a mutation, and no ZAP-70 protein was detected in T cells. ZAP-70 deficiency is associated with a rare immune deficiency with absence of CD8+ T cells as well as a functional deficiency in T cells. Seven months after bone marrow transplantation the child is clinically well and immunologically recoveredporImunodeficiência Primáriajournal article