osmotic fragility

fragility /fra·gil·i·ty/ (frah-jil´it-e) susceptibility, or lack of resistance, to influences capable of causing disruption of continuity or integrity.

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fragility of blood  erythrocyte f.

capillary fragility  abnormal susceptibility of capillary walls to rupture.

erythrocyte fragility  susceptibility of erythrocytes to hemolysis under certain conditions.

mechanical fragility  susceptibility of certain erythrocytes to hemolysis under mechanical stress.

osmotic fragility  susceptibility of certain erythrocytes to hemolysis in increasingly hypotonic saline solutions.

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osmotic fragility,

a sensitivity to changes in osmotic pressure characteristic of red blood cells. Exposed to a hypotonic concentration of sodium in solution, red cells take in increasing quantities of water, swell until the capacity of the cell membrane is exceeded, and burst. Exposed to a hypertonic concentration of sodium in a solution, red cells give up intracellular fluid, shrink, and break up. Laboratory findings of exceptional fragility or resistance may be diagnostic of certain conditions. Hemolysis of normal cells begins in 0.39% to 0.45% salt solution and is complete in 0.30% to 0.33% salt solution in 24 hours at 37° C (98.6° F). Also called erythrocyte fragility.

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osmotic

emanating from or pertaining to the pressure of osmosis.

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osmotic concentration

concentration of osmotically active particles in solutions.

osmotic fragility

the susceptibility of red blood cells to hemolyze in hypotonic saline solutions; may be used as a test of red cell fragility when a series of increasing concentrations is used. See also erythrocyte fragility.

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osmotic fragility

Red blood cell osmotic fragility test Hematology The susceptibility of RBCs to osmotic lysis; in hypotonic solutions, RBCs behave as perfect osmometers, where the free water rapidly equilibrates, causing the RBCs to swell. See Hereditary spherocytosis.