Faculty Opinions recommendation of Clinicopathologic features of nonsystemic vasculitic neuropathy and microscopic polyangiitis-associated neuropathy: a comparative study.
To me, this article is of importance because it indirectly addresses the question of how patients with neuropathy due to isolated vasculitis of the peripheral nervous system should be treated. Non-systemic vasculitic neuropathy (NSVN) is a well described disorder of unknown etiology. Although many case series have been published, it is still unclear whether this is an independent entity or an oligosymptomatic manifestation of a generalized vasculitis, like microscopic polyangiitis or Wegener’s granulomatosis (Kararizou et al., J Rheumatol 2005, 32:853-858 [PMID:15868621]). The question is of importance because the diagnosis of a generalized vasculitis entails a more aggressive immunosuppressive therapy, given the more severe organ involvement and the worse prognosis. Here, the authors compared 23 patients with NSVN and 40 patients with microscopic polyangiitis-associated neuropathy (MPAN) in a retrospective study, analyzing clinical data, electrophysiology and sural nerve biopsies. In brief, the question whether these are different entities or a continuum could not be solved, but differences were found, including more severe neuropathy in MPAN, indicating overall greater clinical severity. A thorough workup is needed in patients with apparent NSVN, because MPAN is an important differential diagnosis, which probably needs more aggressive treatment. Further, preferably prospective studies, including assessment of treatment response, are needed to solve this question.