MRCP UK EXAMINATIONS

Detailed explanation-1: -Green (sodium or lithium heparin) or lavender (EDTA).

Detailed explanation-2: -Methods: The osmotic fragility of hereditary spherocytosis (HS) cases and healthy controls were evaluated by FC-OFT using a series of tubes containing decreasing concentrations of NaCl. The analyses were executed in fresh and incubated (37°C for 24 h) blood samples anticoagulated with EDTA and heparin.

Detailed explanation-3: -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.

Detailed explanation-4: -The most used test at present is NESTROFT, the acronym for Naked Eye Single Tube Redcell Osmotic Fragility Test (5-7). Principle: Microcytic red blood cells are resistant to lysis when exposed to hypotonic solutions.