Abstract
Purpose: :
To report a case of bilateral vitreous hemorrhage and retinal neovascularization in a 6-year-old Hispanic female patient with the C677T 5,10-methylenetetrahydrofolate reductase (MTH-FR) gene mutation, without other known predisposing risk factors.
Methods: :
Case report.
Results: :
A 6-year-old Hispanic female patient with past medical history significant only for eczema was referred in April 2008 for evaluation of bilaterally decreased vision of 4 months duration, with a history of normal vision prior to the onset of her symptoms. She had been treated with pan-retinal photocoagulation by an outside ophthalmologist in March 2008 for retinal neovascularization. At the time of referral, visual acuity was hand motions in the right eye, and counting fingers at 3 feet in the left eye. Bilateral vitreous hemorrhage of unknown etiology was present; she underwent pars plana vitrectomy in both eyes. Intraoperative examination disclosed evidence of regressed retinal neovascularization, but no evidence of retinal artery or vein occlusions. A subsequent workup including thorough medical history, evaluation by a pediatric hematologist and pediatric cardiologist, ocular echography, and extensive laboratory blood analysis for hypercoagulability, was performed. The patient was homozygous for the C677T MTH-FR mutation. Interestingly, however, her serum homocysteine levels were reported normal on two separate occasions. She was not using folic acid or vitamin B6/B12 therapy.
Conclusions: :
MTH-FR gene mutation in the setting of normal serum homocysteine levels is not sufficient to precipitate hypercoagulability. It is however, possible that folic acid deficiency or prolonged dehydration in the past may have been associated with hyperhomocysteinemia. The cause of the patient’s retinal ischemia and neovascularization remains unclear.
Keywords: genetics • retinal neovascularization • vascular occlusion/vascular occlusive disease