Schimke immuno -osseous dysplasia is an autosomal recessive disease, characterized by a dysmorphic syndrome associated with severe renal damage and clinical polymorphism. We report the case of a threeyear - old girl hospitalized for corticosteroid-resistant nephrotic syndrome. A significant edematous syndrome, associated with a dysmorphic syndrome: bulging forehead, micrognathia, triangular face, associated with asymmetry of the two limbs, was discovered during the examination. The assessments revealed severe lymphopenia less than 800/mm3, LTCD4 and LTCD8 lymphopenia with a normal CD4/CD8 ratio and frank B lymphopenia. These elements were observed despite previously well-administered corticosteroid therapy. Schimke syndrome was selected because of the distinctive characteristics. Schimke’s immuno -osseous dysplasia is a rare disease characterized by a clinical polymorphism that includes spondylo -epiphyseal dysplasia, disproportionate stature delay, characteristic facial dysmorphism and corticosteroid-resistant nephrotic syndrome, which is the usual mode of presentation of the syndrome. . The disease progresses to end-stage renal failure. Mutation of the SMARCAL1 gene, which participates in cellular DNA repair processes, explains the clinical polymorphism of this syndrome. In the presence of clinical and immunological signs; the genetic study makes it possible to confirm the diagnosis. Most patients have a life expectancy limited to early childhood or adolescence due to complications represented mainly by stroke, infections and end-stage renal disease. Schimke's immuno -osseous dysplasia is a disease characterized by clinical polymorphism and renal involvement with a guarded prognosis.