What is osmotic fragility of red blood cells?
The osmotic fragility test (OFT) is used to measure erythrocyte resistance to hemolysis while being exposed to varying levels of dilution of a saline solution. When erythrocytes are exposed to a hypotonic environment, water enters the cell and causes swelling and eventual lysis.
What is meant by osmotic fragility?
Definition. Osmotic fragility is a blood test to detect whether red blood cells are more likely to break down.
What is the basis of measuring osmotic fragility of the red blood cell in a sample of blood?
The degree of resistance of red blood cells (RBC) to lysis as a result of a decrease in the NaCl concentration of their environment is the basis of the osmotic fragility test.
What is the normal range of osmotic fragility of red blood cells?
With the technique of Parpart et al (1947), the normal range for osmotic fragility of red blood cells had been estimated to include 5%–45% haemolysis at a salt concentration corresponding to 4.5 g NaCl/l (Dacie 1954).
What is the importance of osmotic fragility?
An osmotic fragility test can be used to help diagnose two hereditary conditions: thalassemia and hereditary spherocytosis: Thalassemia causes your body to make an abnormal form of hemoglobin. Hemoglobin is the protein that allows red blood cells to carry oxygen.
What causes osmotic fragility?
What Is An Osmotic Fragility Test? Two conditions that can cause this to happen are called thalassemia and hereditary spherocytosis (HS). These conditions cause the red blood cells to be more likely to break and become a smaller size. Both thalassemia and HS may lead to hemolytic anemia.
How osmotic fragility is measured?
Osmotic fragility is determined by measuring the degree of hemolysis in hypotonic saline solution. With the unincubated test, red cell osmotic fragility is considered to be increased if hemolysis occurs in a sodium chloride concentration > 0.5%.
How is osmotic fragility test done?
For an osmotic fragility test, you’ll need to give a blood sample. Your red blood cells will be tested to see how easily they break apart in a salt solution. If your red blood cells are more fragile than normal, the test is considered positive.
How osmotic fragility test is done?
What increases red cell fragility?
Pseudohyperkalemia may be due to hemolysis-related potassium release after phlebotomy, ischemia from increased tourniquet time, increased red cell fragility due to rheumatoid arthritis, infectious mononucleosis, red cell membrane disorders, chronic lymphocytic leukemia, and thrombocytosis.
What are the factors affecting osmotic fragility test?
The extrinsic factors include the type, ionic strength and pH of incubation media, type of anticoagulant and storage time of the blood, ambient temperature, drugs, medicinal plant extracts, xenobiotics, chemical agents; whereas intrinsic factors are age, sex, breed, species, pregnancy, lactation and genetic factors.
What are the precautions in erythrocyte osmotic fragility test?
It is recommended that testing should be done within two hours after collection. If the test cannot be performed within this time frame, the blood should be refrigerated. Osmotic fragility testing can be adversely affected by temperature and pH. Hemolyzed sample should not be used.