Nerve Ultrasound as a Decisive Tool in Nonsystemic Vasculitic Neuropathy: A Case Report

INTRODUCTION: The additional value of peripheral nerve ultrasound in acquired immune-mediated neuropathies has recently been reported. Its impact in vasculitic neuropathy is yet to be defined. We report electrophysiological and nerve ultrasound studies in a patient with nonsystemic vasculitic neuropathy at first diagnosis and in response to immunosuppression. CASE REPORT: A 44-year-old female presented with painful neuropathy and weakness of the intrinsic hand muscles. Electrodiagnostic studies revealed severe axonal neuropathy of the nerves of the left arm. On nerve ultrasound, massive and patchy swelling of these nerves was detected. Clinical, laboratory, and radiological evidence of nonneuromuscular involvement and systemic vasculitic diseases was absent. Hence, nonsystemic vasculitic neuropathy was diagnosed without the possibility of histological verification. After 6 months of systemic immunosuppression with steroids and cyclophosphamide, clinical symptoms improved in parallel with neurosonography. In contrast, electrophysiological studies remained pathological despite clinical improvement. CONCLUSIONS: Neurosonography studies in nonsystemic vasculitic neuropathy are rare but might be an ancillary technique to guide noninvasive diagnosis and therapeutic monitoring. Morphological analysis of nerves and changes in response to treatment could be well visualized. Additionally, neurosonography might be useful to target nerve biopsy.