From the Guidelines
The diagnosis and management of peripheral neuropathy should begin with a thorough clinical evaluation, including a detailed history, physical examination, and targeted laboratory testing, with assessment 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, as recommended by the most recent guidelines 1.
Key Diagnostic Steps
- Initial diagnostic steps include blood tests for diabetes, vitamin deficiencies (B12, folate), thyroid function, and immunological markers.
- Assessment for distal symmetric polyneuropathy should include a careful history and assessment of either temperature or pinprick sensation (small-fiber function) and vibration sensation using a 128-Hz tuning fork (for large-fiber function) 1.
- Annual 10-g monofilament testing is recommended to identify feet at risk for ulceration and amputation 1.
Management Approach
- Management focuses first on treating the underlying cause when possible, such as optimizing glycemic control in diabetic neuropathy or correcting nutritional deficiencies.
- For symptom management, first-line medications include gabapentin or pregabalin, with duloxetine and amitriptyline also being effective options 1.
- Topical treatments like capsaicin cream or lidocaine patches may help localized pain.
- Non-pharmacological approaches include physical therapy, transcutaneous electrical nerve stimulation, and lifestyle modifications such as regular exercise and avoiding alcohol.
Patient Education and Follow-Up
- Patient education about foot care is crucial, especially for those with diabetes, to prevent complications like ulcers and infections.
- Regular follow-up is necessary to monitor symptom progression and medication effectiveness, with treatment adjustments made based on response and tolerability 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Peripheral Neuropathy Diagnosis
The approach to diagnosing peripheral neuropathy involves a stepwise evaluation and workup, starting with a detailed history of symptoms, family and occupational history, and a neurological as well as general physical exam 2. Pattern recognition of various neuropathies can help to build a differential diagnosis based on the presentation.
Screening Tests
For asymptomatic patients with disorders that have a high prevalence of peripheral neuropathy, such as diabetes mellitus, a quick and efficient screening test is necessary 3. The 5.07/10-g monofilament test is often used, but its diagnostic accuracy is limited, with sensitivity ranging from 41% to 93% and specificity ranging from 68% to 100% 4. A systematic review and meta-analysis found that monofilament tests had limited sensitivity for screening diabetic peripheral neuropathy, with a pooled sensitivity of 0.53 and specificity of 0.88 5.
Diagnostic Tools
Nerve conduction studies and electromyography (NCS/EMG) are the primary diagnostic tools in the evaluation of patients with large-fiber polyneuropathy 2. Laboratory workup includes serum studies and potentially cerebrospinal fluid, genetic studies, immunological markers, and fat pad biopsy for select patients. 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.
Key Considerations
- A comprehensive history, physical examination, and judicious laboratory testing are required for diagnosis 6
- Early categorization of the type of neuropathy can help focus the workup for peripheral neuropathy 2
- Identification of the etiology of neuropathy is crucial and often time-sensitive, as an increasing number of causes are now reversible or treatable 2
- Treatment of peripheral neuropathy focuses on managing the underlying etiology, and several classes of medications can help alleviate neuropathic pain 6
Diagnostic Approach
The diagnostic approach to peripheral neuropathy involves:
- Clinical evaluation, including a comprehensive neurologic and musculoskeletal examination
- Laboratory testing, including complete blood count, comprehensive metabolic profile, fasting blood glucose, vitamin B12, and thyroid-stimulating hormone levels
- Electrodiagnostic studies, such as NCS/EMG, to help categorize polyneuropathy as primary axonal versus primary demyelinating
- Referral to a neurologist for additional testing, such as nerve biopsy or specific antibody assays, if the initial evaluation is inconclusive 6