[Purine nucleoside phosphorylase deficiency. Report of two cases].

Two brothers with a PNP deficit are reported. The first case presented recurrent upper respiratory infections and died of a sepsis by pseudomonas. The second one was diagnosed when he was six months old and remains asymptomatic. Immunologic tests revealed a deficit of T cell mediated immunity. Treatment consisted on radiated erythrocytes transfusions because HLA compatible donors were not available.