What causes tingling in the extremities?

Causes of Tingling in the Extremities

Tingling in the extremities is most commonly caused by diabetic peripheral neuropathy, vitamin B12 deficiency, nerve compression syndromes, and other types of neuropathies affecting small and large nerve fibers.

Diabetic Neuropathy

• Diabetic peripheral neuropathy is the most common cause of tingling in the extremities, particularly in patients with type 2 diabetes 1
• Symptoms typically start distally in the feet and progress proximally in a "stocking-glove" distribution 1
• Small fiber involvement causes pain, burning sensations, and tingling (dysesthesias) 1
• Large fiber involvement may cause numbness and loss of protective sensation 1
• Symptoms are often worse at night and can significantly impact sleep quality 2

Vitamin Deficiencies

• Vitamin B12 deficiency can cause peripheral neuropathy with tingling and numbness in the extremities 3
• Early intervention with B12 supplementation can reverse both central and peripheral nervous system dysfunction 3
• Other nutritional deficiencies that may cause tingling include folate and vitamin E deficiencies 4

Compression Neuropathies

• Carpal tunnel syndrome (median nerve compression at the wrist) is the most common mononeuropathy, causing tingling in the fingers 4
• Load-related compression neuropathies include:
  • Rucksack palsy (brachial plexus compression from backpack straps) 5
  • Digitalgia paresthetica (compression of sensory digital nerves in the foot) 5
• Nerve fiber compression can cause tingling in the corresponding dermatome 1

Other Neurological Causes

• Small fiber neuropathy can occur in systemic diseases such as Guillain-Barré syndrome, sarcoidosis, neurofibromatosis type 1, and HIV 1
• Chronic inflammatory demyelinating polyneuropathy (CIDP) can cause tingling and numbness 4
• Multiple sclerosis and spinal cord tumors can cause neuropathic symptoms including tingling 1

Vascular Causes

• Erythromelalgia causes episodic burning pain with redness and warmth of the extremities, often triggered by physical activity and warm temperatures 1, 2
• Myeloproliferative disorders (essential thrombocythemia, polycythemia rubra vera) may cause erythromelalgia with tingling 1

Medication and Toxin-Related Causes

• Neurotoxic medications (e.g., chemotherapy agents) can cause peripheral neuropathy 1
• Heavy metal poisoning can lead to tingling sensations 1
• Alcohol abuse can cause peripheral neuropathy with tingling 1

Diagnostic Approach

• Assessment should include evaluation of:
  • Small-fiber function: pinprick and temperature sensation 1
  • Large-fiber function: vibration perception using a 128-Hz tuning fork and 10-g monofilament testing 1
  • Protective sensation: 10-g monofilament 1
• In patients with severe or atypical neuropathy, consider causes other than diabetes, including:
  • Neurotoxic medications
  • Heavy metal poisoning
  • Vitamin B12 deficiency
  • Renal disease
  • Chronic inflammatory demyelinating neuropathy
  • Inherited neuropathies
  • Vasculitis 1

Common Pitfalls in Diagnosis

• Failing to consider non-diabetic causes of neuropathy in patients with diabetes 1
• Overlooking vitamin B12 deficiency, which is treatable and potentially reversible 3
• Not recognizing that up to 50% of diabetic peripheral neuropathy may be asymptomatic, leading to delayed diagnosis 1
• In 20-25% of chronic polyneuropathies, no direct cause can be found despite thorough investigation 4
• Excessive cooling strategies (ice water immersion, powerful fans) used by patients to relieve symptoms can cause tissue damage and worsen the condition 1, 2