Hemolysis

hemolysis /he·mol·y·sis/ (he-mol´i-sis) the liberation of hemoglobin, consisting of separation of the hemoglobin from the red cells and its appearance in the plasma.hemolyt´ic

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immune hemolysis  lysis by complement of erythrocytes sensitized as a consequence of interaction with specific antibody to the erythrocytes.

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he·mol·y·sis (h-ml-ss, hm-lss) or he·ma·tol·y·sis (hm-tl-ss)

n.

The destruction or dissolution of red blood cells, with release of hemoglobin. Also called erythrocytolysis, erythrolysis.

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Hemolysis

The process of breaking down of red blood cells. As the cells are destroyed, hemoglobin, the component of red blood cells which carries the oxygen, is liberated.

Mentioned in: Coombs' Tests, Glucose-6-Phosphate Dehydrogenase Deficiency, Hemolytic Anemia, Hepatitis, Alcoholic, Jaundice, Physical Allergy

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hemolysis (himol´isis),

n the breakdown of red blood cells and the release of hemoglobin that occurs normally at the end of the life span of a red blood cell.

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hemolysis

rupture of erythrocytes with release of hemoglobin.

In a transfusion reaction or in alloimmune hemolytic anemia antibody mediated lysis of red blood cells involves triggering of the complement cascade. Red blood cells also clump together. The agglutinated cells become trapped in the smaller vessels or are phagocytosed and eventually disintegrate.

Some microbes form substances called hemolysins that have the specific action of destroying red blood cells; beta-hemolytic streptococci are an example.

Intravenous administration of a hypotonic solution or plain distilled water will cause the red cells to fill with fluid until their membranes rupture and the cells are destroyed.

Wherever either in vitro or in vivo IgG or IgM antibodies are bound to red blood cell antigens in the presence of complement, the complement cascade is triggered the final products of which include enzymes that result in holes being 'punched' in the wall of the red blood cell, allowing hemoglobin to escape and which is observed as lysis.

Snake venoms and certain plant substances may cause hemolysis. A great variety of chemical agents can lead to destruction of erythrocytes if there is exposure to a sufficiently high concentration of the substance. These chemical hemolytics include copper.

A disorder of the immune response in which antibodies are made to 'self' red blood cell antigens resulting in the lysis of the cells. See also autoimmune hemolytic anemia.

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alpha (a) hemolysis

a characteristic of some bacteria, especially streptococci, manifested by a zone of greenish coloration of cleared agar around a colony of the bacteria on a blood-agar plate. Note that a-hemolysis of staphylococci causes complete lysis. See also streptococcus.

beta (ß) hemolysis

complete hemolysis of sheep and ox erythrocytes by bacteria in culture media. Note that ß-hemolysin of staphylococci causes incomplete hemolysis.

blood transfusion hemolysis

see transfusion reaction.

differential hemolysis

a technique for identification of chimerism, e.g. freemartin calves. Antisera against a single blood group causes only partial hemolysis of the blood composed of two cell populations with different blood cell antigens.

double hemolysis

two types of hemolysis produced on blood agar by alpha and beta lysins found in Staphylococcus aureus and S. intermedius.

extravascular hemolysis

the hemolysis which occurs when fragments of erythrocytes and the majority of aged erythrocytes are phagocytosed directly by the cells of the mononuclear phagocytic system.

hemolysis fever

the rise in body temperature which accompanies each hemolytic incidence of significant size.

fragmentation hemolysis

see microangiopathic anemia.

hemolysis inhibition test

a serological test used in the diagnosis of Corynebacterium pseudotuberculosis infection.

intravascular hemolysis

disruption of red blood cells occurs while they are within blood vessels.

microangiopathic hemolysis

fragmentation hemolysis often associated with microvascular injury, as in disseminated intravascular coagulation, and resulting from a primary disease.

target hemolysis

see double hemolysis (above).