Correlation of livedo racemosa, cutaneous inflammatory plaques, and antiphospholipid antibodies in patients with cutaneous polyarteritis nodosa.

We examined the prevalence of various cutaneous symptoms including livedo racemosa and inflammatory plaques, lupus anticoagulant (LA), anticardiolipin (aCL) antibodies (Abs), and anti-phosphatidylserine-prothrombin complex (anti-PS/PT) Abs in patients with cutaneous polyarteritis nodosa (PAN) to determine if any of them correlate with the clinical and/or serologic features. If such correlations exist, the clinical and serologic features of the cutaneous manifestations could aid in the early diagnosis and/or treatment of cutaneous PAN. We retrospectively investigated the clinical and serologic features, direct immunofluorescence findings, and treatment methods used in 50 patients with cutaneous PAN seen at our Department of Dermatology between 2003 and 2009. Subcutaneous nodules were observed in all 50 patients, 44 (88.0%) had livedo racemosa, 30 (60.0%) had skin ulcers, and 14 (28.0%) had inflammatory plaques. Levels of serum IgM anti-PS/PT Abs were significantly higher in patients with livedo racemosa than in patients without livedo racemosa. Serum IgG anti-PS/PT Ab levels differed significantly between patients with inflammatory plaques (12.86 ± 13.16 U/mL) and those without inflammatory plaques (6.53 ± 5.92 U/mL). Similar trends were seen with respect to IgG aCL Ab levels. In contrast, levels of IgM anti-PS/PT Abs were significantly lower in patients with inflammatory plaques compared to patients without them. Inflammatory plaques were significantly more prevalent in patients with skin ulcers. Warfarin and prednisolone were selected as the primary therapy at a significantly higher rate in patients with inflammatory plaques and skin ulcers than in patients without them. We suggest that a variety of antiphospholipid Abs could influence the cutaneous patterns of cutaneous PAN. In particular, IgG anti-PS/PT Abs and/or IgG aCL Abs could indicate the presence of inflammatory plaques as a specific cutaneous manifestation of cutaneous PAN.