Clinical symptomatology and treatment of diabetic and alcoholic polyneuropathies

1. Big picture

Diabetic and alcoholic polyneuropathies are among the most common acquired chronic polyneuropathies. Both usually produce a distal symmetric length-dependent polyneuropathy, meaning the longest nerves are affected first. Therefore, symptoms begin in the feet and later may involve the hands.

The classic exam pattern is:

burning feet + paraesthesia + distal numbness + reduced ankle reflexes + stocking-glove sensory loss = polyneuropathy

The cause then guides treatment:

• Diabetes mellitus causes metabolic and microvascular nerve injury.

• Chronic alcoholism causes direct toxic nerve damage plus nutritional deficiency, especially thiamine / vitamin B1 deficiency.

The main practical danger in diabetic neuropathy is loss of protective sensation, leading to diabetic foot ulcers, infection, Charcot joints, osteomyelitis, and amputation. In alcoholic neuropathy, always think also about malnutrition and associated alcohol-related neurological disease, especially Wernicke encephalopathy.