Diabetic neuropathy
Diabetic neuropathy is length-dependent nerve damage from chronic hyperglycemia, most often a distal symmetric sensorimotor polyneuropathy causing numbness, pain, and loss of ankle reflexes, with autonomic, mononeuropathy, and radiculoplexus variants. Diagnosis is clinical after excluding other causes; management is tight glycemic control plus gabapentinoid or duloxetine therapy for painful symptoms.
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What this article covers
- Overview
Definition: diabetic neuropathy is a heterogeneous group of nerve disorders caused by chronic hyperglycemia and metabolic dysfunction in diabetes mellitus and impaired glucose tolerance, most…
- Epidemiology
Common with disease duration: risk and prevalence rise with duration of diabetes and degree of chronic hyperglycemia.
- Risk factors
Duration and severity of hyperglycemia: the dominant modifiable driver.
- Pathophysiology
Length-dependent axonal injury: metabolic and microvascular injury to peripheral nerves preferentially affects the longest axons first, producing the classic distal-to-proximal, stocking-glove pattern.
- Clinical features
Distal symmetric sensorimotor polyneuropathy (most common): length-dependent loss of light touch, pinprick, and vibration sensation, loss of the ankle reflex, and, in advanced disease, distal…
- Differential diagnosis
Chronic inflammatory demyelinating polyradiculoneuropathy: proximal and distal weakness with demyelinating features on EMG (slowed conduction, conduction block), unlike the sensory, axonal pattern of diabetic polyneuropathy.
- Diagnosis
Diagnostic basis: distal symmetric diabetic polyneuropathy is a clinical diagnosis in a patient with established diabetes or impaired glucose tolerance plus the characteristic length-dependent…
- Management
First step - optimize glycemic control: tight glycemic control, along with exercise and management of dyslipidemia, obesity, and metabolic syndrome, can slow the progression and improve symptoms of…
- Complications
Foot ulceration and amputation risk: loss of protective sensation predisposes to unrecognized trauma, ulceration, and, if complicated by infection or ischemia, lower-extremity amputation.
- Prognosis
Distal symmetric polyneuropathy: generally slowly progressive and not reversible once established, though progression can be slowed with sustained glycemic control; painful symptoms may partially…
- Prevention
Glycemic control from diagnosis: sustained tight glycemic control (individualized hemoglobin A1c target, generally close to or below 7%) reduces the incidence and progression of diabetic neuropathy…
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