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Alteration, dissolution, or destruction of red blood cells in such a manner that hemoglobin is liberated into the medium in which the cells are suspended, e.g., by specific complement-fixing antibodies, toxins, various chemical agents, tonicity, alteration of temperature. SYN: erythrocytolysis, erythrolysis, hematolysis. [hemo- + G. lysis, destruction]
- α′ h. h. observed in blood agar cultures of occasional strains of pneumococci or streptococci; the zone of h. about the colony is greenish caused by a partial decomposition of hemoglobin.
- β h. complete or “true” h. observed in blood agar cultures of various bacteria, especially hemolytic streptococci and staphylococci; virtually all of the erythrocytes are destroyed in a relatively wide, regularly circumscribed, circular zone about the colony, thereby resulting in a clear “halo” of transparent agar; the zone of h. is frequently much wider than the diameter of the colony; the degree of change varies with species of erythrocytes.
- biologic h. h. caused by materials elaborated by various living organisms.
- conditioned h. SYN: immune h..
- γ h. a term sometimes used to indicate that there is no h. in relation to bacterial colonies in or on blood agar; thus, nonhemolytic organisms may be referred to as producing γ h..
- immune h. h. caused by complement when erythrocytes have been sensitized by specific complement-fixing antibody. SYN: conditioned h..
- phenylhydrazine h. (fen′il-hi′-dra-zin) an in vitro test for glucose-6-phosphate dehydrogenase (G6PD) deficiency; hem olysis resulting from in vitro addition of phenylhydrazine to blood with red cells which are deficient in G6PD, with the appearance of Heinz-Ehrlich bodies.
- venom h. that caused by hemolytic material in the venom of various species of snakes or other venomous animals.
- viridans h. α′ h..
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he·mo·ly·sis or chiefly Brit hae·mo·ly·sis hi-'mäl-ə-səs, .hē-mə-'lī-səs n, pl -ly·ses -.sēz lysis of red blood cells with liberation of hemoglobin see ALPHA HEMOLYSIS, BETA HEMOLYSIS
he·mo·lyt·ic or chiefly Brit hae·mo·lyt·ic .hē-mə-'lit-ik adj
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he·mol·y·sis (he-molґə-sis) [hemo- + -lysis] disruption of the integrity of the erythrocyte membrane causing release of hemoglobin; it may be caused by bacterial hemolysins, by antibodies that cause complement-dependent lysis, by placing erythrocytes in a hypotonic solution, or by defects in the cell membrane. Called also erythrocytolysis, erythrolysis, and hematolysis.Medical dictionary. 2011.