Atypical Chronic Inflammatory ANCA-Positive Deforming Arthritis After Cocaine-Levamisole Exposure.

Background/Objective: Immunostimulatory drugs including immune checkpoint inhibitors and levamisole can induce inflammatory disease including vasculitis, rashes, tissue necrosis, and arthritis. Methods: This prospective cohort study determined the 5-year outcomes of cocaine-levamisole-induced inflammatory disease as to outcomes and survival. Thirty-one consecutive cocaine-levamisole autoimmune patients and 45 primary vasculitis patients were characterized as to clinical differentiating features, antineutrophil cytoplasmic antibody (ANCA) status, treatment, the presence of acute and chronic arthritis, and 5-year outcome. Results: Seventy-one percent (22/31) of cocaine-levamisole vasculopathy cases were ANCA positive (86% p-ANCA and 14% c-ANCA), whereas 53% (23/45) of the primary vasculitis were ANCA positive (p = 0.04). The ANCA-positive cocaine-levamisole cohort at onset were characterized by younger age (45 +/- 12 vs 53 +/- 14 years, p = 0.04), superficial skin necrosis (82% vs 54%, p = 0.036), depressed complement C3 (27% vs 4%, p = 0.33), antiphospholipid antibodies (50% vs 4%, p < 0.001), neutropenia (18% vs 0%, p = 0.044), and elevated antimyeloperoxidase (MPO) antibody levels (100% vs 67%, p < 0.001). Chronic cocaine-levamisole disease was characterized by severe cicatrical deformities of the face and extremities (45.5% vs 8.3%, p = 0.005). Arthralgias (71% vs 82%, p = 0.19) and acute arthritis (33% vs 32%, p = 0.25) were similar between the 2 groups. However, a substantial proportion cocaine-levamisole-induced autoimmune patients (18% vs 0%, p = 0.045) developed a chronic deforming inflammatory arthritis that was rheumatoid factor, anti-cyclic-citrillinated antibody antibody, and HLA-B27 negative, but p-ANCA- and MPO antibody positive. Conclusions: Patients exposed to cocaine-levamisole may develop serious chronic sequelae including cicatrical cutaneous and facial deformities and an atypical seronegative, p-ANCA and MPO antibody-positive, HLA-B27-negative chronic deforming inflammatory arthritis.