In visual loss due to giant cell arteritis reversible?

Giant cell arteritis (GCA) is a common systemic vasculitis with an unknown etiology. It mainly affects people older than 50 years of age and often presents with symptoms such as headache, jaw claudication, visual loss, polymyalgia rheumatica and increased erythrocyte sedimentation rate (ESR). Established blindness is irreversible if the steroid treatment is not administered within a few days. Here, we report a case of GCA in a patient with a normal ESR whose left eye perceived just light at the initiation of treatment. Immediately prior to the combined treatment with high dose oral steroids and cyclophosphamide, the ESR level had increased to 80 mm/h and the vision improved after the combined treatment four months later.