Red blood cell sorbitol in diabetic children

When red blood cells (RBC) were incubated with various concentrations of glucose, the RBC sorbitol level increased in a concentration-dependent manner. The elevated RBC sorbitol level was not reduced by further incubation in a glucose-free medium. In both diabetic and non-diabetic children, an increase of RBC sorbitol levels occurred in the oral glucose tolerance test and the return to baseline was delayed in diabetics compared with non-diabetics. In the majority of diabetics (87%), RBC sorbitol levels exceeded the upper limit of the normal range, which was arbitrarily determined as the mean + 2 s.d., in healthy non-diabetic children and adults. A good correlation was observed between RBC sorbitol levels and plasma glucose levels (r = 0.644). In both diabetics and non-diabetics, no correlation was observed between RBC sorbitol levels and age, and in diabetics the RBC sorbitol level was not related to the duration of disease. A good correlation was observed between RBC sorbitol levels, and hemoglobin Alc (HbAlc) or fructosamine levels in diabetic children.