Factors Associated With Relapse, Prognosis in Cutaneous Polyarteritis Nodosa Identified

In patients with cutaneous polyarteritis nodosa (CPAN), the presence of ≥1 cutaneous ulcer prior to treatment may be associated with a poor prognosis, with serum C-reactive protein (CRP) level, blood absolute neutrophil count (ANC), neutrophil-to-lymphocyte ratio (NLR), and systemic immune-inflammation index (SII) all potential markers of disease relapse, according to the results of a retrospective case series. The study was conducted at a dermatology clinic in Japan, and results were reported in JAMA Dermatology.

The investigators sought to identify clinical and laboratory markers associated with relapse among patients with CPAN. Among 30 patients with CPAN, a total of 21 with histopathologic evidence of disease were enrolled in the study. Of these, 16 were women; median patient age at diagnosis was 49 years (range, 11-74 years). Median follow-up was 42 months (range, 8-374 months). Relapse was defined as “the first recurrence or new onset of cutaneous disease that required further escalation of treatment with prednisolone at a dosage of greater than 20 mg/d and/or add-on use of immunosuppressant therapy, more than 6 months after initial treatment.”

Pretreatment factors were evaluated statistically in the group with and the group without disease relapse. The presence of pretreatment cutaneous ulcer was significantly associated with relapse (0 of 11 in the nonrelapse group vs 4 of 10 in the relapse group; P <.05). Based on laboratory test results, significantly higher mean values were reported in the relapse arm vs nonrelapse arm for the following parameters: CRP level (6.03 mg/dL vs 0.23 mg/dL, respectively; 95% CI, 0.01 mg/dL-10.8 mg/dL; P =.01); mean ANC (6.0 x 10³/μL vs 3.4 x 10³/μL, respectively; 95% CI, 1.9 x 10³/μL-14.6 x 10³/μL; P =.001); mean NLR (2.8 vs 1.4, respectively; 95% CI, 1.1-4.9; P =.002); and mean SII (11.7 x 10⁵ vs 5.1 x 10⁵, respectively; 95% CI, 3.3 x 10⁵-31.1 x 10⁵; P =.007).

The estimated 2-year cumulative relapse rate was significantly higher among patients with blood ANC of >4.9 x 10³/μL vs those with blood ANC of ≤4.9 x 10³/μL (90% [9 of 10] vs 18% [2 of 11], respectively; 95% CI, 6%-72%).

The investigators concluded that pretreatment status of cutaneous ulcer presence, elevated serum CRP level, blood ANC, NLR, and elevated SII are all linked with possible relapse and worse prognosis among patients with CPAN.

Reference

Kato A, Hamada T, Miyake T, et al. Clinical and laboratory markers associated with relapse in cutaneous polyarteritis nodosa. JAMA Dermatol. 2018;154:922-926