burr cell

Burr cells can also arise in vitro due to elevated pH, blood storage, ATP depletion, calcium accumulation, and contact with glass.

Burr cells usually imply uremia, but are seen in many conditions, including mild hemolysis in hypomagnesemia and hypophosphatemia, hemolytic anemia in long-distance runners, and pyruvate kinase deficiency.

Acanthocytes should be distinguished from echinocytes, which are also called 'burr cells', which although crenated are dissimilar in that they have multiple, small, projecting spiculations at regular intervals on the cell membrane.

This can cause false results in assays such as coagulation assays (causing falsely increased clotting times) or blood cell differentials (causing a false increase in poikilocytes, particularly burr cells.)