A generic term for any diabetes mellitus (DM)–related disorder of the peripheral nervous system, autonomic nervous system, and some cranial nerves.
This most common of the chronic complications of DM can affect the peripheral or the autonomic nervous system, singly or in combination. Peripheral neuropathies can cause bilaterally symmetric hypesthesia, hyperesthesia, paresthesia, loss of temperature and vibratory sense, or causalgia. With more advanced disease, deep tendon reflexes and proprioception may be impaired. Peripheral mononeuropathies (Bell palsy, radiculopathy) can mimic neurologic diseases of other origin. Sensory neuropathy is believed to play a role in at least half of all lower limb amputations in patients with DM by blunting awareness of cutaneous injuries, which then fail to heal because of macrovascular circulatory impairment. Sensory neuropathy to a degree that can lead to ulceration or gangrene can be detected by examination of the foot with a 10-g monofilament. Involvement of the autonomic nervous system may be manifested by postural hypotension, dysphagia, gastroparesis, alternating diarrhea and constipation, and impotence. The pathogenesis of chronic diabetic neuropathy is poorly understood. Symptoms tend to progress and the response to treatment is unpredictable. In contrast, cranial nerve palsies due to microangiopathy in DM often resolve spontaneously.
Reference: Stedman's Medical Dictionary