Antineutrophil cytoplasmic antibody-positive scleritis: Clinical profile of patients from a tuberculosis-endemic region

Purpose: To report the clinical profile of a series of antineutrophil cytoplasmic antibody (ANCA) -associated scleritis in Indian population. Methods: We conducted a retrospective review of medical records of 33 eyes of 26 consecutive patients with scleritis, who tested positive for either antibody to proteinase 3 [anti-PR3/cytoplasmic antineutrophil cytoplasmic antibody (cANCA)] or myeloperoxidase [anti-MPO/perinuclear anti-neutrophil cytoplasmic antibody (pANCA)] between 2006 and 2015. Results: The mean age at presentation was 54.1 (11.1) years and 61.5% of the patients were female. Underlying systemic disorder was found in 46.2% of patients and includes granulomatosis with polyangitis (30.8%) and tuberculosis (15.4%). Necrotizing scleritis (48.5%) was the most common scleritis observed, followed by diffuse anterior scleritis (42.4%). Positive cANCA was found in 65.4% of patients and 34.6% was found positive for pANCA. Four of the six patients with positive Mantoux test were started on anti-tuberculosis treatment (ATT) by pulmonologist. Cyclophosphamide was the most common immunosuppressive and 11.5% of the patients required combination of two immunosuppressives. Seventeen eyes developed cataract and four eyes required patch graft. Female gender was more frequently associated with pANCA-associated scleritis than cANCA (P = 0.037). Incidence of necrotizing scleritis was higher in patients with positive cANCA, but this difference was not statistically significant (P = 0.806). cANCA-positive patients had statistically significant higher association with systemic rheumatic diseases (P = 0.021). Conclusion: Necrotizing scleritis is the most common subtype of scleritis in ANCA-positive individuals and even in the absence of systemic involvement. All patients with ANCA positivity should be thoroughly screened to rule out any evidence of tuberculosis, especially in tuberculosis-endemic region before planning aggressive immunomodulatory therapy.