Osmotic fragility test

Citation Sang Hyuk Park , Chan-Jeoung Park , Bo-Ra Lee , Young Jin Kim , Young-Uk Cho , Seongsoo Jang , Kyung Nam Koh , Ho-Joon Im , Jong Jin Seo , Hye-Lim Jung , Eun Sil Park , Ji Won Lee , Keon Hee Yoo , Hyun-Sook Chi; Screening For Hereditary Spherocytosis: EMA Binding Test and Flow Cytometric Osmotic Fragility Test Are Recommended, But Cryohemolysis Test Is Not Recommended. Blood 2013; 122 (21): 3425. doi: Download citation file: • • • • • • • • • Background The hallmark of laboratory test for the diagnosis of hereditary spherocytosis (HS) has been osmotic fragility (OF) test. However, OF test gives false negative results in 10% - 20% of HS patients and false positive results in autoimmune hemolytic anemia (AIHA) patients. Currently, the eosin 5-maleimide (EMA) binding test and hypertonic cryohemolysis (HCH) test have been proposed as screening tests in recently published guidelines for the diagnosis of HS ( Br J Haematol 2012;156:37-49). And the flow cytometric OF (FC OF) test is recently developed as an assay that can replace the classical OF test. In this study, we evaluated the performance of 3 screening tests (EMA binding test, FC OF test, and HCH test) for the diagnosis of HS. Methods A total of 151 patients [32 for HS, 40 for AIHA, 40 for anemia of chronic disease (ACD), 39 for iron deficiency anemia (IDA)] and 140 normal controls (NCs) were enrolled in this study. EMA binding test, FC OF test, and HCH test were performed separately in each patient. Reference ra...

This test can be used to confirm a suspected diagnosis of Hereditary Spherocytosis (HS). HS is a common inherited hemolytic anemia characterized by the presence of spherical erythrocytes (spherocytes). HS is diagnosed based on family history and clinical features, along with clinical laboratory tests, including peripheral smear examination, osmotic fragility (OF), flow cytometry, or by genetic testing (Hereditary Hemolytic Anemia Panel Sequencing. ARUP test code 2012052). Band 3 (or solute carrier family 4 member 1, SLC4A1) is the most abundant transmembrane protein found in human red blood cells (RBC). Eosin-5-maleimide (EMA) dye binds to band 3 on intact RBC's. A reduction of fluorescence intensity will be seen in hereditary spherocytosis. This test by flow cytometry has been reported to have a sensitivity of 93 percent for a diagnosis of HS. Congenital Dyserythropoietic Anemia Type II, Southeast Asian Ovalocytosis and Hereditary Pyropoikilocytosis are rare disorders that may also show a positive result. This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes. CPT Codes The American Medical Association Current Procedural Terminology (CPT) codes published in ARUP's Laboratory Test Directory are provided for informational purposes only. The codes reflect our interpretati...

Hereditary spherocytosis and hereditary elliptocytosis are congenital red blood cell (RBC) membrane disorders that can cause a mild hemolytic anemia. Symptoms, generally milder in hereditary elliptocytosis, include variable degrees of anemia, jaundice, and splenomegaly. Diagnosis requires demonstration of increased RBC osmotic fragility and a negative direct antiglobulin test. Rarely, patients < 45 years with symptomatic disease require splenectomy. Hereditary spherocytosis (chronic familial icterus; congenital hemolytic jaundice; familial spherocytosis; spherocytic anemia) is an autosomal dominant disease with variable gene penetrance. About 25% of cases are sporadic. Hereditary spherocytosis is characterized by hemolysis of spheroidal RBCs and anemia. In hereditary spherocytosis, the cell membrane surface area is decreased disproportionately to the intracellular content due to loss of proteins associated with the cell membrane. The decreased surface area of the cell impairs the flexibility needed for the cell to traverse the spleen’s microcirculation, causing intrasplenic hemolysis. • In hereditary spherocytosis, symptoms and signs are usually mild. The anemia may be so well compensated that it is not recognized until an intercurrent viral illness, such as parvovirus infection, transiently decreases RBC production, causing an aplastic crisis. These episodes can be self-limited, resolving with resolution of the infection, while others require urgent treatment. Moderate ja...

[ Erythrocyte fragility refers to the propensity of [ citation needed] When multiple levels of stress are applied to a given population/sample of cells, a fragility profile can be obtained by measuring the relative or absolute extent of hemolysis existing at each such level, indexes stability," though technically stability refers to cells' resistance to both stress-induced lysis and spontaneous auto-lysis. [ citation needed] Erythrocyte osmotic fragility [ ] Osmotic fragility (OF) refers to the degree or proportion of The osmotic fragility test is common in increased OF include decreased OF include chronic liver disease, iron deficiency anemia, thalassemia, hyponatremia, polycythemia vera, hereditary xerocytosis, New approaches to testing OF are under development to better facilitate its use in disease diagnosis and screening, such as by utilizing microfluidic devices along with cell counting. Erythrocyte mechanical fragility [ ] Mechanical fragility (MF) refers to the degree or proportion of Uses of erythrocyte mechanical fragility can include diagnostic testing, It's also notable that there can be a qualitative difference between a mechanical fragility test involving a comparatively lower energy stress, such as by agitating one or more beads in the presence of the sample (a common approach [ citation needed] Related erythrocyte properties [ ] Susceptibility to hemolysis from causes other than osmotic or mechanical forces are not as common, but may sometimes be referred t...

Osmotic Fragility The increase in osmotic fragility is a property of the spheroidal shape of the cell and is independent of the cause of the spherocytosis. From: Dacie and Lewis Practical Haematology (Twelfth Edition), 2017 Related terms: • Patient • Edetic Acid • Mean Corpuscular Hemoglobin • Erythrocyte Disorder • Spectrin • Anemia • Elliptocytosis • Hemolytic Anemia • Hereditary Spherocytosis Robin K. Ohls, in Fetal and Neonatal Physiology (Fifth Edition), 2017 Osmotic Fragility The osmotic fragility of red blood cells is a composite index of their shape, hydration, and, within certain limitations, proneness to in vivo destruction. 164,174 Preterm and term infants have an increased osmotic resistance. 175,176 The osmotic fragility of neonatal cells begins to revert towards adult values shortly after birth, and osmotic resistance reaches adult values by 4 to 6 weeks of age. There is no known advantage to the increased osmotic resistance seen in the neonatal red blood cell. However, studies of osmotic fragility in neonates have practical implications. It has been suggested that the diagnostic criteria for hereditary spherocytosis used in adults and older children are unreliable in newborn infants. For example, spherocytes are not regularly seen in all infants with hereditary spherocytosis. Indeed, spherocytes may be frequently found in ABO incompatibility. When one is performing an osmotic fragility test, a neonatal osmotic fragility curve must be used rather than an adul...

Both a whole blood EDTA specimen and a shipping control specimen are required. Patient: Specimen Type: Whole blood Container/Tube: Lavender top (EDTA) Specimen Volume: 4 mL Collection Instructions: 1. Refrigerate specimen immediately after collection. 2. Send whole blood specimen in original tube. Do not aliquot. 3. Rubber band patient specimen and control vial together. Normal Shipping Control: Specimen Type: Whole blood Container/Tube: Lavender top (EDTA) Specimen Volume: 4 mL Collection Instructions: 1. Collect a shipping control specimen from a normal (healthy), unrelated, nonsmoking person at the same time as the patient. 2. Clearly hand write “normal control” on the outermost label. 3. Refrigerate specimen immediately after collection. 4. Send control specimen in original tube. Do not aliquot. 5. Rubber band patient specimen and control vial together. The control and patient specimen must be handled in the same manner from specimen collection to receipt in the testing laboratory. Spherocytes are osmotically fragile cells that rupture more easily in a hypotonic solution than do normal red blood cells . Because they have a low surface area:volume ratio, they lyse at a higher osmolarity than do normal discocytes (ie, RBC). Cells that have a larger surface area:volume ratio, such as target cells or hypochromic cells, are more resistant to lysing. After incubation, an increase in hemolysis is seen in spherocytes. Hereditary spherocytosis typically has a greater number of ...