Nephropathic Cystinosis Presenting as Renal Fanconi Syndrome without Glycosuria

Abstract

Renal Fanconi syndrome is diagnosed by its cardinal features of glycosuria without diabetes, aminoaciduria, phosphaturia, and renal tubular acidosis. It is often associated with hypokalaemia, hypophosphatemia and rickets. We report a seven-year-old boy with nephropathic cystinosis who presented with all the cardinal features of renal Fanconi syndrome associated with rickets, pathological fractures, stage IV chronic kidney disease (CKD) and hypothyroidism. Slit-lamp examination of the cornea confirmed the diagnosis. However glycosuria was conspicuously absent. Whenever there are features of rickets with failure to thrive and recurrent vomiting renal rickets should be ruled out. Cystinosis is one such disorder and we report this case due its rarity and interesting clinical presentation.

Keywords

• cystinosis
• glycosuria
• renal fanconi syndrome