Abstract
Hemoglobin C (Hb C) disease is caused by a mutation that leads to reduced hemoglobin solubility, crystallization, and chronic hemolysis. We report on a patient with a homozygous Hb C disease, persistent fetal hemoglobin, and a heterozygous factor II mutation. This case illustrates the complex interaction between hemoglobinopathies and thrombophilia disorders, where the coexistence of Hb C disease and a factor II mutation significantly heightens the risk of thrombosis. Its geographic prevalence in the Caribbean, particularly Puerto Rico, reflects historical migration patterns and underscores the need for early detection and multidisciplinary care.