Prothrombin deficiency with recurrent subretinal hemorrhage.

Ocular hemorrhage has been recorded in congenital factor deficiencies like hemophilia A, but it has never been documented in prothrombin deficiency. Here, we describe an unusual case of sudden vision loss in the right eye caused by subretinal hemorrhage following a coughing episode in a 67-year-old woman. Notably, the patient underwent left eye enucleation 12 years previously under similar circumstances due to subretinal hemorrhage. During the interview, it was discovered that the patient had a history of prothrombin deficiency, which was subsequently confirmed through laboratory testing. Aside from recurrent ocular bleeding and 1 instance of bleeding following dental extraction in childhood, there is no other history of bleeding. Subsequent molecular studies revealed a homozygous missense mutation at G1499A (Arg500Gln), a variant previously identified as R457Q. Although the likelihood of prothrombin deficiency initiating subretinal hemorrhage is low, it is likely to worsen retinal hemorrhage and contribute to difficulty in controlling bleeding. A comprehensive coagulation workup is essential in patients with ocular hemorrhage. Determining factor II activity should be included in individuals exhibiting variably prolonged prothrombin time and activated partial thromboplastin time with correction in mixing studies. Additional investigations, such as genetic sequencing and family studies, are advised for those with isolated low prothrombin levels.