Disorders of peripheral nerves are among the most frequent neurological complications of diabetes. The number of patients with diabetic neuropathy worldwide is increasing along with the prevalence of diabetes itself. Diabetes can affect peripheral sensory and motor nerves, thoracic nerves, cranial nerves or autonomic nerves. Diabetic neuropathy can manifest itself in multiple ways. It can affect multiple sensory and motor nerves in distal parts of the limbs (diabetic polyneuropathy) or affect one nerve at a time (diabetic mononeuropathy). It can also primarily affect the autonomic nerves and cause diabetic autonomic neuropathy.
The symptoms of diabetic neuropathy depend on the type of neuropathy. In diabetic polyneuropathy, the patients may experience unusual sensations (paresthesias), numbness and pain in their hands and feet. In addition there may be weakness of the muscles in the feet and hands. In diabetic mononeuropathy, the symptoms depend on which nerve is affected. For example it can affect thoracic nerves and cause numbness and pain in the chest wall or it can affect cranial nerves and cause sensory or motor deficits in the face. In diabetic autonomic neuropathy, the patients may experience persistent nausea, vomiting, diarrhea, constipation, incontinence, sweating abnormalities or sexual dysfunction.
Diagnosis of diabetic neuropathies is based on history, clinical examination and supporting laboratory investigations. These include electromyography with nerve conduction studies, skin biopsies to evaluate cutaneous nerve innervation, and nerve and muscle biopsies for histopathological evaluation.
Treatment of diabetic neuropathies depends on optimum diabetic control, exercise and weight loss to reduce insulin resistance, and symptomatic control when paresthesias are painful. Neuropathic pain due to diabetic neuropathy can be treated with anti-seizure medications, antidepressants, or analgesics, including opiate drugs. In severe painful conditions patients may be referred to the Blaustein Chronic Pain Clinic for a multidisciplinary approach to pain management.