1. Osmotic fragility in HS
Osmotic fragility in HS. In the osmotic fragility test, red cells are suspended in salt solutions of varying tonicities between isotonic saline (0.9 g/dl NaCl; left) and distilled water (right). Normal red cells swell in hypotonic media and eventually reach a limiting spherical shape, beyond which they hemolyze. Spherocytes, which begin with a lower than normal surface/volume ratio, can swell less before they reach their limiting volume; hence, their osmotic fragility curve is shifted to the left (higher salt concentrations). The spherocytes are said to be osmotically fragile. Before splenectomy, a small proportion of the red cells are extra fragile and produce a tail on the osmotic fragility curve. These cells have been conditioned by the spleen, as shown by their higher concentration in the splenic vein and especially in the splenic cords.576 (From Lux and Palek.4 Used by permission.)
Source: Hereditary Spherocytosis and Hereditary Elliptocytosis, The Online Metabolic and Molecular Bases of Inherited Disease
Citation: Valle D, Beaudet AL, Vogelstein B, Kinzler KW, Antonarakis SE, Ballabio A, Gibson K, Mitchell G. The Online Metabolic and Molecular Bases of Inherited Disease; 2014 Available at: Accessed: October 06, 2017
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