A hereditary clue for the development of cutaneous polyarteritis nodosa in siblings

We read with great interest the case report by Kizawa et al. [1] about cutaneous polyarteritis nodosa (PAN) in siblings. The authors described two sisters with cutaneous PAN who shared almost identical clinical symptoms, including erythematous nodules and leg pain during childhood. This uncommon report suggested that a single inherited factor must be involved in disease pathogenesis, although PAN including cutaneous PAN has been thought to be a...