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Phagocytosed malaria pigment

From haematologyetc.co.uk


Appearance:

In the context of malarial infection the neutrophils may contain masses of phagocytosed brown or golden malaria pigment within their cytoplasm.



Images of malaria pigment

Images of neutrophils containing malaria pigment: Image 1 shows a schizont in the process of releasing daughter parasites at the end of asexual reproduction – note the golden pigment that will also be released. Images 2 & 3 show phagocytosed malaria pigment. Note also that the neutrophils show features of both activation (with hypergranulation and vacuolation) and apoptosis (condensed and vacuolated nucleus). Image 3 also shows malaria parasites.


Cause:

Malaria pigment is the iron-containing residue that is formed following the metabolism of haemoglobin by the parasites. It is the “detoxified” remains of the haem portion of the molecule. When the red cell ruptures at the end of asexual (schizont) development the pigment is released and is taken up by neutrophils or monocytes, and remains until they are cleared from the circulation (after about 72hrs).


Significance:

  • The percentage of neutrophils containing malaria pigment increases with disease severity
  • The malaria pigment is reported to paralyse and reduce the effectiveness of neutrophils