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Phagocytosis of erythrocytes

From www.haematologyetc.co.uk


Appearance:

Neutrophils phagocytosing red cells that have been opsonised by autoantibody.



Images of phagocytosis of erythrocytes by neutrophils:

Phagocytosed erythrocytes may be very clearly seen and easily identified as red cells (image 1) or may have the appearance of red cell ghosts that contain no haemoglobin so resemble large round vacuoles within the erythrocyte cytoplasm. Sometimes both erythrocytes and red cell ghosts may be seen together within a single neutrophil (image 2).



Cause:

The autoantibody usually affects children with viral infection, it can also occur idiopathically in adults


Described by:

Donath and Landsteiner


Significance:

The biphasic IgG autoantibody usually recognises the P antigen, and binds in cold areas of the body (i.e. the extremities) fixing complement to the red cells. The cells subsequently circulate to warmer areas of the body and undergo complement-mediated hemolysis. This causes intravascular haemolysis with haemoglobin in the urine – paroxysmal cold haemoglobinuria (PCH).