PURPOSE: To report on isolated central retinal artery occlusion (CRAO) as an initial presentation in two patients with undiagnosed paroxysmal nocturnal hemoglobinuria (PNH). METHODS: CRAO related to the aggravation of PNH was observed in 2 of 98 consecutive PNH patients for 10 years. Ocular and systemic manifestations were evaluated before and after systemic steroid, eculizumab and anticoagulant administration with adjuvant ocular treatments. RESULTS: Two young patients presented with complaints of acute painless monocular vision loss. In both cases, fundus examination revealed retinal edema and a cherry-red spot in the macula, consistent with CRAO. On systemic evaluation, severe anemia and thrombocytopenia were observed, and simultaneously thrombogenic processes were suggested by increased D-dimers, fibrinogen degradation products and/or portal vein thrombosis. PNH testing of red blood cells revealed a CD55 and CD59 deficiency consistent with PNH in both cases. The systemic complications typically associated with thrombosis were not observed for the following several months with early conservative treatments including eculizumab. CONCLUSIONS: Acute blindness from CRAO can be a unique manifestation of undiagnosed PNH and its subsequent aggravation. Systemic evaluations including PNH testing, especially in young CRAO patients, are strongly recommended for early detection of the further systemic thrombogenic processes.
PURPOSE: To report on isolated central retinal artery occlusion (CRAO) as an initial presentation in two patients with undiagnosed paroxysmal nocturnal hemoglobinuria (PNH). METHODS: CRAO related to the aggravation of PNH was observed in 2 of 98 consecutive PNH patients for 10 years. Ocular and systemic manifestations were evaluated before and after systemic steroid, eculizumab and anticoagulant administration with adjuvant ocular treatments. RESULTS: Two young patients presented with complaints of acute painless monocular vision loss. In both cases, fundus examination revealed retinal edema and a cherry-red spot in the macula, consistent with CRAO. On systemic evaluation, severe anemia and thrombocytopenia were observed, and simultaneously thrombogenic processes were suggested by increased D-dimers, fibrinogen degradation products and/or portal vein thrombosis. PNH testing of red blood cells revealed a CD55 and CD59 deficiency consistent with PNH in both cases. The systemic complications typically associated with thrombosis were not observed for the following several months with early conservative treatments including eculizumab. CONCLUSIONS: Acute blindness from CRAO can be a unique manifestation of undiagnosed PNH and its subsequent aggravation. Systemic evaluations including PNH testing, especially in young CRAO patients, are strongly recommended for early detection of the further systemic thrombogenic processes.