Diabetic neuropathy may often go unnoticed in the early stages when symptoms may be minor or even absent. Diagnosis is made based on clinical examination and is confirmed by certain tests.

Some of the steps taken in diagnosing diabetic neuropathy include:

• Detailed clinical examination of the peripheries such as the legs, feet, fingers, toes and hands to look for signs of muscle wasting, numbness or loss of sensation.
• Obtaining details of any symptoms.
• Examination of blood pressure that may fluctuate with posture change such as on standing up or leaning over which can indicate autonomic neuropathy.
• Muscle strength, reflexes and sensitivity to vibration and hot or cold temperatures are tested.
• Any affected areas are lightly touched with a nylon monofilament after blindfolding the patient. If the touch is not detected or if the touch is felt with unusual intensity or pain, diabetic neuropathy is suspected.
• A detailed foot examination is very important as the foot is one of the most commonly affected sites in peripheral diabetic neuropathy. People with diabetic neuropathy may hurt their feet without noticing because the neuropathy has caused their feet to become numb to pain. With time, such injury fails to heal (also due to high blood sugar) and may progress to diabetic foot or gangrene of the foot. People diagnosed with peripheral neuropathy therefore need frequent foot exams.
• Further confirmatory tests include nerve conduction studies and electromyography. These detect nerve impulses and muscle contraction in response to external nerve stimulation. If impaired, diabetic neuropathy is suspected. These tests help to determine the type and extent of the nerve damage. These tests are rarely needed to diagnose diabetic neuropathy.
• Detailed examination of heart health and ultrasound examinations to check the health of other internal organs.
• Routine blood checks to monitor blood sugar levels and aid tight blood sugar control.