Wiskott-Aldrich syndrome complicated by an atypical lymphoproliferative disorder: a case report.

Wiskott-Aldrich syndrome (WAS) is an X-linked syndrome consisting of eczema, recurrent pyogenic infection, and thrombocytopenia with decreased platelet volume. Immunologic studies reveal normal immunoglobulin G (IgG), decreased IgM, elevated IgA and IgE levels, and decreased T-cell function. Patients with WAS often have increased susceptibility to lymphoproliferative disorders (LPDs). We report a 3-year-old boy who had persistent thrombocytopenia with bleeding, recurrent infections, and chronic eczema with frequent skin infections since birth. A blood smear revealed small platelets (50% of normal size). Immunologic studies showed normal IgG (1880 mg/dL), decreased IgM (76 mg/dL) and increased IgA (228 mg/dL) and IgE (14,282 IU/mL) levels. The relative proportions of immune cells were CD2 52.2%, CD3 41.1%, CD4 23.4%, CD8 16.8%, CD19 8.0%, CD57 7.7% and active T cells 14.6%. T-cell dysfunction was detected on the multitest for cell-mediated immunity. The WAS diagnosis was confirmed by mutation analysis which demonstrated a 4-base pair deletion in WAS protein gene exon 1. His thrombocytopenia was uncontrolled despite intravenous immunoglobulin infusions, so splenectomy was performed. The platelet count then rose to about 60,000 to 80,000/microL. However, about 2 weeks after splenectomy, he developed generalized lymphadenopathy and lymphoma was misdiagnosed based on lymph node biopsy at another hospital where he was admitted for urgent care. However, our analysis of his lymph node pathology led to the diagnosis of atypical LPD (ALPD). The lymphadenopathy regressed spontaneously 1 month later without chemotherapy. Early and correct diagnosis of WAS complicated with ALPD is important to avoid unnecessary chemotherapy.