 i. Intravascular: Intrinsic RBCs defects leading to hemolytic anemia eg, enzyme deficiencies, hemoglobinopathies, membrane defects. Extrinsic: liver disease, hypersplenism, infections eg, bartonella, babesia, malaria, treatment with oxidizing exogenous agents eg, dapsone, nitrites, aniline dyes, exposure to other hemolytic agents eg, lead, snake and spider bites, lymphocyte leukemia, autoimmune hemolytic disorders. 