Purine nucleoside phosphorylase deficiency associated with a fatal lymphoproliferative disorder

A 2 1/2-year-old boy presented with an illness resembling glandular fever. He was found to have T-cell deficiency with lack of red and white cell purine nucleoside phosphorylase enzyme activity. A spastic tetraparesis was noted. The patient subsequently died of a malignant lymphoma of the B-immunoblastic type.