Clinical Guidance
Schimke immunoosseous dysplasia (SIOD) is characterized by a constellation of clinical findings that affect a variety of organ systems. Nearly all affected individuals have disproportionate short stature, spondyloepiphyseal dysplasia causing hip disease, nephrotic syndrome that progresses to end-stage renal disease (ESRD), hyperpigmented macules, and immunodeficiency (primarily cellular immunodeficiency). Central nervous system vasculopathy (migraines, transient ischemic attacks, strokes), thyroid dysfunction, and cytopenias are also common. Secondary complications include hypertension, anemia, elevated lipids, recurrent infections, and osteopenia. Although not defining features of SIOD, bone marrow failure and lymphoproliferative disease have been reported . Based on review of the medical literature to date, more than 100 individuals have been identified with biallelic pathogenic variants in SMARCAL1. The following description of the phenotypic features associated with this condition is based on these reports. Table 2. Frequency of Physical, Radiographic, and Laboratory Features in Individuals with Schimke Immunoosseous Dysplasia Confirmed on Molecular Testing
