Cicatrising conjunctivitis and severe dry eye syndrome revealing systemic sarcoidosis initially misdiagnosed as mucous membrane pemphigoid

A woman in her 60s with severe dry eye symptoms since 2007 was initially diagnosed with stage II mucous membrane pemphigoid in 2012 and treated with systemic immunosuppressive therapy. The initial conjunctival biopsy report described linear deposition of complement along the epithelial basement membrane without immunoglobulin deposition on direct immunofluorescence, findings considered suggestive of ocular mucous membrane pemphigoid. In 2017, she was referred to our tertiary cornea unit due to progressive ocular surface disease despite treatment. Examination revealed severe cicatrising conjunctivitis with forniceal shortening and symblepharon formation. Repeat conjunctival biopsy demonstrated non-caseating granulomas with negative direct immunofluorescence for immunoglobulins and complement. Systemic evaluation showed mediastinal lymphadenopathy and pulmonary involvement also and transbronchial biopsy confirmed systemic sarcoidosis. During follow-up, additional osseous involvement was identified. Despite systemic treatment, the patient developed chronic ocular surface disease requiring intensive medical therapy, as well as ocular surface reconstruction. This case highlights the importance of considering sarcoidosis in the differential diagnosis of cicatrising conjunctivitis, particularly in atypical cases or when immunofluorescence findings are inconclusive or discordant with the clinical course