Plasma Chitotriosidase activities in different test groups. Normal pediatric controls (∆), normal adult controls (▲), pediatric controls with renal Fanconi syndrome (○), pediatric controls with ESRD (●), adult renal controls with microalbuminuria (□), adult renal controls with ESRD (∎ ) and Cystinotic patients; European (♦) and Egyptian (◊). Forty five cystinotic patients were compared to 54 healthy pediatric controls, 33 healthy adult controls, 24 renal disease pediatric patients (12 with Fanconi syndrome and 12 with ESRD) and 30 renal disease adult patients (15 with albuminuria and 15 with ESRD). Nine newly diagnosed Egyptian patients were compared to all controls below 5 years of age (26 normal and 13 renal). Averages of duplicates were used. Horizontal bars represent the median value for each group.