The evaluation of small fiber neuropathy: a survey of American Academy of Neurology members (P4.140)

Objective: To determine how neurologists evaluate and test for small fiber neuropathy.

Background: Small fiber neuropathy (SFN) affects the thinly myelinated and unmyelinated sensory and autonomic nerve fibers. Symptoms of SFN can be difficult for practitioners to recognize. There is clinical and etiological heterogeneity, and sometimes SFN overlaps with the more commonly recognized distal symmetric large fiber polyneuropathy. Clinical practice in the evaluation of distal symmetric polyneuropathy has been demonstrated to differ amongst neurologists, neuromuscular specialists and internists.

Design/Methods: We surveyed 798 neurologists who are members of the American Academy of Neurology (AAN) including 400 members randomly selected from a pool of neurologists who, according to internal AAN records, had indicated neuromuscular medicine to be either a primary or secondary subspecialty. The second half of the sample consisted of randomly selected members who had indicated neuromuscular medicine to neither be a primary nor a secondary specialty. Respondents answered a survey instrument with a list of serum tests and procedures for different neuropathy clinical scenarios.

Results: The survey response rate was 29.3% (234/798), with 67.9% of respondents identified as specializing in neuromuscular medicine. When asked which tests they would order given a clinical scenario of distal symmetric SFN, neuromuscular specialists were more likely to order electromyography/nerve conduction studies, skin biopsy for SFN, anti-nuclear antibodies, oral glucose tolerance tests, and serum immunofixation compared to non-neuromuscular neurologists who were more likely to order a serum folate level.

Conclusions: Our findings reveal that neuromuscular neurologists are more likely to order as part of their initial evaluation of SFN serum tests recommended in the AAN practice parameter for distal symmetric polyneuropathy and skin biopsies for pathological confirmation of SFN. The development of an AAN practice parameter for SFN may help promote consistent practice amongst neurologists of all subspecialties.

Disclosure: Dr. Thawani has nothing to disclose. Dr. Adams has nothing to disclose. Dr. Brannagan has received personal compensation from Grifols, Catalyst, and Baxter. Dr. Callaghan has received research support from Imepto Medical Inc.