Fatal lymphoproliferative disorder in a child with Schimke immuno-osseous dysplasia.

Schimke immuno-osseous dysplasia (SIOD) is a rare autosomal recessive disorder characterized by spondyloepiphyseal dysplasia, nephrotic syndrome, and cell-mediated immunodeficiency. Mutations in the SMARCAL1 gene (SW1/SNF2-related, matrix-associated, actin-dependent regulator of chromatin, subfamily a-like1) cause SIOD. We report a patient with SIOD and SMARCAL1 mutations, who presented with fever of unknown origin secondary to B-cell lymphoma. To our knowledge, this is the first report of an SIOD patient with a primary lymphoproliferative disorder (LPD).