Background/Purpose: Anti-RNA polymerase III IgG antibody (Pol3) is associated with diffuse cutaneous scleroderma. Depending on the population studied, Pol3 prevalence in scleroderma patients ranges from 9-20% whereas its reported prevalence is less than 1% in healthy individuals. Pol3 is therefore considered highly specific for scleroderma. Emerging data suggests that this antibody is also associated with co-temporal development of malignancy in the scleroderma population. The purpose of this study was to determine the prevalence of Pol3 in patients with delayed wound healing.

Methods: The Wound Etiology and Healing (WE-HEAL) Study is an IRB approved biospecimen and data repository designed to investigate the immunologic features of delayed wound healing. A proportion of WE-HEAL patients undergo autoimmune serologic profiling (including Pol3) as part of their ongoing clinical care due to either skin graft failure, planned surgical intervention or prior to initiation of immunosuppressants. Testing for Pol3 was performed by RDL Reference Laboratory (Los Angeles, CA) with a result of >20 units considered positive. In patients with positive Pol3 results we investigated the percentage of scleroderma and other autoimmune diseases.

Results: Of the 568 patients enrolled in the WE-HEAL study at the time of data lock, Pol3 was positive in 9 out of 167 patients (5.4%) who had the test performed. There was no significant difference in baseline characteristics or wound outcome between Pol3 positive patients and Pol3 negative patients. (Table 1). Only 1 of the 9 patients with positive Pol3 had scleroderma (11.1%). This patient had longstanding diffuse scleroderma and was also diagnosed with metastatic breast cancer at the same time that her wounds developed. Of the other 8 patients one patient had a history of cervical cancer but 7 had no active or prior malignancy. In this cohort Pol3 was associated with other immune mediated skin disorders with a prevalence of 4.7% in Hidradenitis Suppurativa, 20% in patients with Sjogren’s Syndrome and 11.7% in patients with Rheumatoid Arthritis.

Conclusion: In this longitudinal cohort of patients with delayed wound healing Pol3 antibody was positive in 5% of patients tested which is higher than expected based on prevalence of this autoantibody in the general population. We postulate that Pol3 may not be unique to scleroderma and that other autoimmune mediated skin conditions such as vasculitic leg ulcers and hidradenitis may also be associated with Pol3 positivity. The findings suggest that patients with immune mediated wound issues have a higher than expected Pol3 positivity rate, a finding which further investigation in this ongoing longitudinal study.