Compound Heterozygosity for the C6777T Mutation of the MTHFR Gene and the FII G20210A Mutation of the Prothrombin Gene in Sequential Bilateral Anterior Ischemic Optic Neuropathy.

Nonarteritic anterior ischemic optic neuropathy (NA-AION) is the most common form of acute painless, usually unilateral, optic neuropathy in the elderly population. Systemic risk factors include diabetes mellitus, arterial hypertension, sleep apnea syndrome, and cardiovascular disease. Α 52-year-old man developed sequential, bilateral NA-AION, involving a worsening, severe vision compromising attack in the secondly affected eye. Thrombophilia testing revealed compound heterozygosity for the C6777T mutation of the MTHFR gene and the prothrombin G20210A (FII mutation). Oral anticoagulation treatment was initiated. A thorough systemic and family history, especially in the absence of major vasculopathic disease, should alert toward investigation for thrombophilia in middle-aged patients with atypical forms of NA-AION and initiation of anticoagulant treatment should be considered.