Neuropathy, diabetic

• Diabetic polyneuropathy
• Metabolic polyneuropathy

• 250.60 Diabetes mellitus with neurological manifestations type 2 or unspecified type not states as controlled
• 357.2 Polyneuropathy in diabetes

• E13.40 Diabetes, diabetic (mellitus) with neuropathy

• 5G: Impaired motor function and sensory integrity associated with acute or chronic polyneuropathies

Description

• Damage to peripheral sensory (most common) and/or motor neurons
• Most likely due to demyelination, inflammation, ischemia or infarction from as yet poorly understood metabolic abnormality

Essentials of Diagnosis

• Distinct clinical syndromes include
  • Distal, symmetrical, primarily sensory polyneuropathy affecting feet and legs in a chronic, slowly progressive manner (most common)
    • Usually unnoticed by patient until fairly progressed
    • Most common complaint is persistent numbness or tingling, worse at night
  • Acute ophthalmoplegia affecting cranial nerve III (oculomotor) and less often cranial nerve VI (abducens) on one side
  • Acute mononeuropathy of limbs or trunk, including painful thoracolumbar radiculopathy
  • Acute or sub-acute painful, asymmetrical, predominantly motor multiple neuropathy affecting upper lumbar roots and proximal leg muscles (diabetic amyotrophy)
  • Symmetrical, proximal motor weakness and wasting, usually without pain, with variable sensory loss, pursing sub-acute or chronic course
  • Autonomic neuropathy involving bowel, bladder, sweating, circulatory reflexes

General Considerations

• Sensory loss puts patient at risk for skin tears, skin breakdown
• Sensory and motor loss can result in loss of normal forces on joints, particularly foot and ankle, causing joint deformity over time
• Sensory and motor loss puts patient at higher risk for injury, acute and repetitive
• Peripheral nerve damage most common in lower extremities, but may occur in the upper extremities

Demographics

• 15% of patients with diabetes have symptoms of polyneuropathy
• 50% of cross-sectional sample of people with diabetes have evidence of peripheral nerve damage on nerve conduction velocity testing
• Less than 10% have clinical neuropathy on diagnosis of diabetes
• Infrequent in people under 30 years of age

Signs and Symptoms

• Numbness
• Tingling
• Weakness, muscle atrophy
• Loss or impairment of deep tendon reflexes, vibration, proprioception
• Pain, burning, stabbing
• Impaired balance
• Altered gait
• Impaired vision
• Orthostatic hypotension

Functional Implications

• Fall risk with mobility on uneven or unpredictable surfaces
• Injury risk with items of unknown sharpness or temperature
• Impaired driving due to lower-extremity neuropathy or ophthalmoplegia
• Difficulty with fine motor tasks (writing, grooming, cooking, feeding, bathing)
• Difficulty with gross motor tasks (transfers, gait, stair climbing, dressing)

Possible Contributing Causes

• Cardiovascular risk factors associated with “metabolic syndrome” thought to be risk factors for diabetic polyneuropathy: triglyceride levels, body mass, hypertension
• Poorly controlled diabetes results in higher likelihood of developing polyneuropathy

Differential Diagnosis

• Spinal cord injury
• Guillain–Barré syndrome
• Tabes dorsalis
• Lumbar radiculopathy
• Peripheral vascular disease
• Lyme disease
• Leprosy
• HIV-related neuropathy
• Lupus erythematosus
• Sarcoidosis ...