Diabetic neuropathy: classification, measurement and treatment.

PURPOSE OF REVIEW

Diabetic neuropathies comprise a number of conditions affecting somatic or autonomic nerves and are the most common of the long-term diabetic complications. This review considers recent developments in the classification and noninvasive assessment of somatic neuropathy, and describes new approaches to the management of painful neuropathic symptoms.

RECENT FINDINGS

Classification of the diabetic neuropathies needs modifying to include the recently described 'prediabetic neuropathy' or 'neuropathy of impaired glucose tolerance'. There is increasing evidence to support the use of minimally invasive skin biopsies for evaluating small fibre neuropathies, and more recently, the noninvasive corneal confocal microscopy, which enables direct visualization of peripheral nerve in vivo. For those with painful neuropathic symptoms, a number of evidence-based therapies are now available.

SUMMARY

Patients with 'idiopathic neuropathy' should be screened for evidence of impaired glucose tolerance and considered for lifestyle management. Future trials of potential therapies will benefit from more relevant surrogate endpoints. Those with painful neuropathy should only be prescribed therapies whose efficacy has been confirmed by independent randomized controlled trials.