Diabetic neuropathy is a type of nerve damage that can occur if you have diabetes. Diabetic neuropathy is a common serious complication of diabetes. Diabetic neuropathy can affect all the nerve types including cranial nerves but commonly affects the peripheral nerves especially of the legs and can spread to the upper limbs.
The commonly encountered symptoms and signs are:
Types of Diabetic Neuropathy
Diabetic neuropathy is broadly categorized as:
Generalised neuropathy – Can be sensory fibres or motor fibres or both sensorimotor fibres are involved
Focal or multifocal neuropathy, Eg:
- Cranial neuropathy like double vision, facial weakness
- Entrapment neuropathies such as carpel tunnel syndrome
- Lumbosacral radiculoplexus neuropathy eg: pain in the thighs
Diabetic neuropathy can also exclusively affect the very small nerve fibres and can cause small fibre neuropathy. Symptoms include:
- Burning pain mainly in the feet and hands
- Sometimes abnormal skin sensations such as tingling or itchiness.
- Pain is more severe during nights
- Increased sensitivity to pain- Pain to non-painful stimuli (Hypoesthesia)
- Reduced ability to differentiate hot from cold
Another rare form of diabetic neuropathy is Autonomic neuropathy causing symptoms
- Fainting /dizziness due to fall in blood pressure related to posture eg:Orthostatic hypotension and palpitations.
- GI symptoms such as bloating, diarrhea, nausea, malabsorption, constipation
- Urinary symptoms such as increase in urge, incontinence, retention, infections
- Heat intolerance, increased sweating or loss of sweating
Nature of damage in Diabetic Neuropathy
- Microangiopathy or small blood vessel damage to the nerves
- Toxic end products of abnormal glucose metabolism in diabetes eg: free oxygen radicles, Sorbitol and nitric oxide.
Diagnosis of Diabetic Neuropathy
A good clinical examination followed by some laboratory tests such as
- Blood test
- Check urine for protein
- Nerve conduction studies
- Tests for blood flow in the limbs .eg: doppler studies
- Imaging such as nerve ultrasound and MRI
Management of Diabetic Neuropathy
Good Glycemic control
- Tight and stable glycemic control is probably the most important for slowing the progression of neuropathy
- The Diabetes Control and Complications Trial (DCCT) demonstrated that tight blood sugar control in patients with type1 diabetes decreased the risk of neuropathy by 60% in 5 years.
Physical Measures such as Walking, Foot care, customised foot ware, physiotherapy, TENS/Ultrasound therapy
Drugs that help with symptomatic relief include Pregabalin, Gabapentin, Carbamazepine and Sodium Valporate, opoids for pain management, Tricyclic anti-depressants, SSRIs, Duloxetine
Vitamin supplementation such as Zinc sulfide showed improvement in glycemic control and B vitamins to reduce the symptoms of neuropathy
Surgical treatment is useful for entrapment neuropathies such as carpal tunnel syndrome. In extreme cases of foot ulcers, amputation is required to prevent spread of infection.
Measures such as compression stockings, fluid intake help prevent fall in blood pressure and also special drugs to help in the management of autonomic neuropathy causing gastric, urinary symptoms are used in clinical practice.
Diabetic neuropathy is thus a common complication of diabetes and needs diagnosis and treatment as early as possible to prevent complications. Occasionally patients get diagnosed with Diabetes Mellitus when they present with signs and symptoms of neuropathy. Awareness to seek medical help at the appropriate time is the key to successful management of Diabetic neuropathy.
Article by Dr. Bhuvaneshwari Rajendran
MBBS, MRCP(UK), CCT(UK)
Consultant Neurology and Clinical Neurophysiology
Kauvery Hospital