Nephropathic cystinosis is a rare autosomal recessive lysosomal disease 
characterized by accumulation of pathognomonic cystine crystals in renal and 
other tissues of the body. Cystinosis is caused by mutant cystinosin, the 
cystine transport protein located in lysosomal membranes, leading to systemic 
deposits of cystine and resultant end organ damage. Cystinosis is rarer in 
Asians than Caucasians with only a handful of cases reported from India to date. 
Due to its extreme rarity and clinically insidious presentation in contrast to 
the infantile form, the diagnosis of juvenile nephropathic cystinosis is 
frequently delayed or overlooked. Moreover, routine processing and sectioning of 
paraffin embedded tissues dissolves cystine crystals, making it difficult to 
diagnose this condition on light microscopic examination alone, mandating 
electron microscopic (EM) analysis of renal biopsies for an accurate diagnosis 
of this condition. We describe a case of juvenile nephropathic cystinosis 
presenting with uveitis and photophobia in a 17-year-old Indian male, diagnosed 
after EM examination of the patient's renal biopsy for evaluation of nephrotic 
syndrome. While highlighting the diagnostic utility of EM, we describe a few 
histopathologic clues which can prompt inclusion of EM analysis of renal 
biopsies in this setting.