Purpose: To analyze the potential cause of retinal arterial occlusion in a 9-year-old child.
Methods: Case report. Antithrombin III, protein C, free protein S, activated protein C resistance, and antiphospholipid antibodies in plasma were determined. Determination of factor V R506Q (Leiden mutation), thermolabile methylene tetrahydrofolate reductase by polymerase chain reaction, and restriction enzyme analysis were performed.
Results: The patient was found to be heterozygous for factor V R506Q (Leiden mutation) and homozygous for thermolabile methylene tetrahydrofolate reductase.
Conclusion: Coexistence of two mild hereditary thrombophilic states may result in severe thrombotic manifestations in young people.