Hands that feel like they’re burning; feet that make it feel like you’re walking on pins and needles; numbness that spreads gradually up the limbs. These are among the most vexing of symptoms for patients and their doctors alike. Many patients spend years going from doctor to doctor seeking a diagnosis, and many doctors order test upon test, with no firm conclusion.
Now a Rochester neurologist has helped compile a national set of guidelines that aim to help doctors better diagnose the most common cause of such symptoms more quickly and efficiently and with less expense.
David Herrmann, MBBCh, director of the Peripheral Neuropathy Clinic at Strong Memorial Hospital, is an author of the guidelines for a painful nerve condition known as neuropathy, which affects millions of people with diabetes and many other patients as well. The new practice parameters were published last month in the journal Neurology.
The symptoms of nerve damage vary greatly among patients: Burning pain, tingling, numbness, and weakness are all common. The new guidelines focus on patients with distal symmetric polyneuropathy, which generally describes nerve damage that is most often in the hands and feet, and arms and legs. The condition has a variety of causes, including diabetes, poor nutrition, HIV, certain medications, excessive alcohol consumption, or simply, genetics.
“Neuropathy can be very difficult to pin down, and there are dozens upon dozens of tests that a doctor can order in an attempt to properly diagnose the patient,” said Herrmann. “The new parameters are designed to help patients by giving physicians the tools they need to arrive at a proper diagnosis efficiently.”
Herrmann and colleagues recommend that doctors begin by ordering three blood tests to identify the cause of neuropathy: measuring levels of blood glucose and vitamin B12, as well a test known as serum protein electrophoresis and immunofixation. The guidelines also recommend the use of genetic analysis in some cases, to either rule out or pin down a specific inherited form of the disorder. Charcot-Marie-Tooth disease is the most common inherited form of neuropathy.
Guidelines also support the use of specialized tests, including skin biopsy, for some patients. Herrmann is an expert in the use of skin biopsy to identify neuropathy and track its progression. He is also currently developing a new technique that uses a specialized microscope to look beneath the skin to gauge the condition of a person’s nerves in the fingers, as a way to possibly eliminate the need for a biopsy in some patients.
Herrmann notes that once identified, symptoms in a majority of patients with neuropathy can be treated successfully – the pain is lessened or reduced, for instance, or feeling returns to hands and feet that had been numb. In some instances, the nerve damage can actually be reversed.
“Anything we can do to improve the lives of these patients would be tremendous,” said Herrmann, who is associate professor of Neurology and of Pathology and Laboratory Medicine. “For a particular form known as small fiber neuropathy, many patients are told that the problem is all ‘in their head’ and not real, because a doctor can’t find evidence of the condition. And so the patients search for answers for years, all the while suffering needlessly. It’s very unfortunate. Skin biopsy can be helpful to identify neuropathy in such patients.”
The new parameters are a result of a collaboration between the American Academy of Neurology, the American Association of Neuromuscular and Electrodiagnostic Medicine, and the American Academy of Physical Medicine and Rehabilitation. The effort was led by neurologist John D. England, M.D., of Louisiana State University Health Sciences Center.