Vasculitic peripheral neuropathy in patients with provisional cutaneous arteritis

Cutaneous arteritis (CA) is a skin-limited medium-vessel vasculitis. Some patients with CA also exhibit extracutaneous manifestations, such as vasculitic peripheral neuropathy (VPN). VPN is likely underdiagnosed because nerve biopsies are invasive and often impractical. This study proposed the concept of provisional CA to better identify patients with neuropathic involvement and to evaluate the prevalence and electrophysiological features of VPN.

We retrospectively analysed patients with provisional CA treated at the Severance Hospital between 2011 and 2024. Provisional CA was defined as skin-limited medium-vessel vasculitis with neuropathic symptoms in the lower limbs irrespective of a nerve biopsy. VPN was defined based on established clinical and electrophysiological criteria. Demographic, clinical, and laboratory data were collected from the electronic medical records.

Thirty-six patients met the provisional CA criteria. The median age was 51.0 years, and 36.1% of the patients were male. Among these, 22 (61.1%) demonstrated electrophysiological evidence of VPN. Pure sensory neuropathy and sensorimotor involvement were observed in 59.1% and 40.9% of patients, respectively. The most frequently affected nerves were the peroneal (63.6%) and sural (54.5%) nerves. No significant differences were found between the patients with and without VPN in terms of age, sex, skin manifestations, or laboratory findings.

VPN was prevalent in patients with provisional CA. Clinical features alone were insufficient to predict nerve involvement. Nerve conduction studies serve as a valuable diagnostic tool when a nerve biopsy is not feasible and may facilitate the earlier detection and management of neuropathic complications in skin-limited vasculitis.