Clinical features of Epstein-Barr virus infection in primary immunodeficiency patients

Recurrent respiratory infections are frequent in healthy children. The association with peculiar signs and symptoms such as splenomegaly, lymphopenia, and hypogammaglobulinemia should induce suspicion of primary immunodeficiency (PID). The described case is an example of early detection of PID due to heterozygous gain of function mutation of the gene coding for p110 PI3K subunit responsible for APDS (activation PI3 kinase delta syndrome). Recently recognized, APDS is a combined immunodeficiency charac-terised by recurrent pulmonary infections, CMV and EBV viremia and lymphadenopathy. The typical immunological pattern of this syndrome is: hypogammaglobulinemia charac-terised by altered levels of IgM (more often increased but sometimes normal or decreased levels have been reported) associated with reduction in IgG and IgA levels; altered distribution of the T cell subsets (CD4+ lymphopoenia) and anomalous compartment B (expansion of transitional B cells and reduction in memory B cells). In the reported case, although the patient presented with an incomplete phenotype, early diagnosis was guided by the immuno-disregulation red flags (splenomegaly, chronic EBV viremia and persistent otorrhea) and therapy was promptly instituted in order to reduce the onset of long-term complications.