X-linked lymphoproliferative syndrome (XLP or Duncan disease) is characterized by extreme sensitivity to Epstein-Barr virus (EBV), resulting in a complex phenotype manifested by severe or fatal infectious mononucleosis, acquired hypogammaglobulinemia and malignant lymphoma.
Patients with SH2D1A mutations displayed severe acute infectious mononucleosis with hyperimmunoglobulin M, hypogammaglobulinemia, and B-cell malignant lymphoma.
The manifestations of XLP generally occur following Epstein-Barr virus (EBV) infection and include fulminant mononucleosis, hypogammaglobulinemia and lymphoma.
However, compared with XLP caused by SLAM-Associated Protein deficiency (SH2D1A mutation), XIAP deficiency was originally observed to be associated with a high incidence of hemophagocytic lymphohistiocytosis (HLH) and a lack of lymphoma, suggesting that classification of XIAP deficiency as a cause of XLP may not be entirely accurate.
We propose SH2D1A mutational screening be considered in male patients with or without hypogammaglobulinemia who received rituximab treatment for lymphoma and did not recover immunoglobulin G in a year after B-depleting therapy.