The American Academy of Neurology has developed new, evidence-based guidelines to support the most accurate diagnosis for distal symmetric polyneuropathy (DSP). The guidelines, published in the December 3, 2008, online issue of Neurology®, find that a combination of laboratory and genetic blood tests and other specialized assessments like autonomic testing and nerve and skin biopsy appear to be the most helpful tests for finding the cause of DSP.
"There are many people with a neuropathy who have been walking around for years without having been diagnosed and treated," said guidelines author John D. England, MD, FAAN. "Both neurologists and people with neuropathy need to know that the appropriate choice of tests is critical to accurate diagnosis."
The guidelines were developed in full collaboration with the American Association of Neuromuscular & Electrodiagnostic Medicine and the American Academy of Physical Medicine and Rehabilitation. Authors analyzed all available scientific studies on the topic.
The guidelines recommend that doctors obtain certain blood tests for all patients with numb, painful feet. "People with suspected nerve problems should talk to their doctors about screening tests, especially blood glucose, vitamin B12 level and serum protein levels, since these tests can often point to common causes of neuropathy," said England. The guidelines recommend tailored genetic testing for accurately diagnosing certain neuropathies that run in families.
The guidelines further recommend that doctors consider a combination of specialized tests to accurately evaluate neuropathies with autonomic dysfunction. These tests measure the action of the nerves that control sweating, heart rate, and blood pressure. Skin biopsy may also be useful to diagnose loss of tiny nerve fibers in the skin.