Neuropathy is well recognized as a major complication of insulin-dependent
diabetes mellitus in adults, resulting in significant morbidity and possibl
y an increased mortality. Both the peripheral and autonomic nervous systems
can be involved, and adolescents with diabetes can show early evidence of
neuropathy. The pathogenesis of diabetic neuropathy remains unclear but is
thought to involve various mechanisms. This complication can be traced to t
he metabolic effects of hyperglycemia and/or other effects of insulin defic
iency on the various constituents of the peripheral nerve. The polyol pathw
ay and/or nonenzymatic glycation affecting one or more cell types in the mu
lticellular constituents of the peripheral nerve appear likely to have an i
nciting role. The role of other factors, such as possible direct neurotroph
ic effects of insulin and insulin-related growth factors, seems to be relev
ant.