Hematological involvement in nephropathic cystinosis: new insights

Abstract Nephropathic cystinosis (NC) is a rare autosomal recessive lysosomal storage disease characterized by defective lysosomal efflux of cystine due to variations in the CTNS gene encoding the lysosomal cystine transporter, cystinosin. This leads to pathological crystal accumulation in almost all tissues and organs in the body, affecting their functions. NC primarily affects the kidneys followed by a cascade of extrarenal organ involvement later in life. There are few reports of hematological complications as anemia or cytopenias; nevertheless, most of the reported data have been derived from case reports or small case series. Anemia/cytopenias in NC can be multifactorial in origin. Early identification and timely management of these alterations are critical to better growth, improved outcome, and quality of life of NC patients. Early diagnosis of NC, early initiation of both supportive and definitive cystine-depleting treatment, and adherence to therapy remain the mainstay for disease control and prevention of progression of some extrarenal complications. We hereby review hematological findings in NC, discuss the underlying contributing factors, suggest work-up, and highlight treatment options for hematological complications in NC patients. Given the multisystem nature of NC, we recommend integrated NC care approach with involvement of hematologist into its multidisciplinary team.