From the Guidelines
The workup for neuropathy in patients with diabetes should include a careful history and assessment of either temperature or pinprick sensation and vibration sensation using a 128-Hz tuning fork, as well as annual 10-g monofilament testing to identify feet at risk for ulceration and amputation. According to the most recent guidelines 1, all people with diabetes should be assessed for diabetic peripheral neuropathy starting at diagnosis of type 2 diabetes and 5 years after the diagnosis of type 1 diabetes, and at least annually thereafter. The assessment should include:
- A careful history to identify symptoms of neuropathy
- Assessment of temperature or pinprick sensation (small-fiber function)
- Vibration sensation using a 128-Hz tuning fork (for large-fiber function)
- Annual 10-g monofilament testing to identify feet at risk for ulceration and amputation Additionally, symptoms and signs of autonomic neuropathy should be assessed, including orthostatic dizziness, syncope, or dry cracked skin in the extremities, and signs such as orthostatic hypotension, a resting tachcardia, or evidence of peripheral dryness or cracking of skin 1.
The workup may also involve laboratory tests, such as complete blood count, comprehensive metabolic panel, hemoglobin A1c, vitamin B12 level, and thyroid function tests, as well as additional tests based on clinical suspicion, such as erythrocyte sedimentation rate, C-reactive protein, and antinuclear antibody 1. Nerve conduction studies and electromyography may be essential to characterize the type of neuropathy, and imaging studies such as MRI of the spine may be necessary if radiculopathy is suspected.
It is also important to note that diabetic neuropathy is a diagnosis of exclusion, and nondiabetic neuropathies may be present in people with diabetes and may be treatable 1. Therefore, a comprehensive approach to identify the underlying cause of neuropathy is crucial for appropriate treatment, as management strategies differ significantly depending on the etiology of the neuropathy.
From the Research
Workup for Neuropathy
The workup for neuropathy involves a systematic approach to diagnose and manage the condition.
- The diagnosis requires careful clinical assessment, judicious laboratory testing, and electrodiagnostic studies or nerve biopsy if the diagnosis remains unclear 2.
- A comprehensive history, physical examination, and judicious laboratory testing are essential for diagnosis 3.
- Initial laboratory evaluation includes a complete blood count, comprehensive metabolic profile, fasting blood glucose, vitamin B12, and thyroid-stimulating hormone levels 2, 3.
Laboratory Tests and Diagnostic Studies
- Electrodiagnostic studies, including nerve conduction studies and electromyography, can help in the differentiation of axonal versus demyelinating or mixed neuropathy 2, 4.
- Lumbar puncture and cerebrospinal fluid analysis may be helpful in the diagnosis of Guillain-Barré syndrome and chronic inflammatory demyelinating neuropathy 2.
- Skin biopsy may be used to assess intraepidermal nerve fiber density if small-fiber neuropathy is suspected, and nerve biopsy may be useful in select cases 4.
- Magnetic resonance imaging and neuromuscular ultrasound have also shown promise in the evaluation of peripheral neuropathy 4.
Treatment and Management
- Treatment should address the underlying disease process, correct any nutritional deficiencies, and provide symptomatic treatment 2.
- Several classes of medications, including gabapentinoids and antidepressants, can help alleviate neuropathic pain 3, 5.
- Individualized multidisciplinary patient care is facilitated by careful consideration of pain-related disability and patient education 5.
- An algorithmic approach with dosing recommendations is provided for the treatment of neuropathic pain associated with peripheral neuropathy 6.