Cutaneous manifestations of vasculitic or vasculopathic processes can pose a diagnostic challenge, particularly when systemic symptoms are absent. We report a case of an adult patient who presented with nonpainful petechiae and blue-purple discoloration of the lower extremities three days after a self-limited upper respiratory infection. Laboratory testing revealed elevated erythrocyte sedimentation rate, white blood cell count, and C-reactive protein, as well as positive cytoplasmic antineutrophil cytoplasmic antibody (c-ANCA) titers. No other systemic findings or organ involvement were identified. A punch biopsy of the affected skin demonstrated vascular changes with a differential diagnosis that included lymphocytic vasculopathy. The patient was managed with short-course systemic corticosteroids and close observation as the lesions gradually resolved without complications. This case highlights an atypical, skin-limited c-ANCA-associated lymphocytic vasculopathy, emphasizing the importance for physicians to maintain vigilance for subtle cutaneous signs of autoimmune or inflammatory disease even in the absence of systemic involvement.
Jones et al. (Tue,) studied this question.