Pam-malarial LDH and Pan-malarial aldolase
Background:
These two proteins are enzymes related to glycolysis pathways of metabolism active in all malaria species. Since malaria parasites have specific forms of these proteins, antibodies do not cross-react with human aldolase. Antibodies to these proteins therefore have the potential to recognise all species of malaria ”.
Use of pan-malarial antibodies in RDT tests
Outside of Africa, RDT tests often combine a species-specific with a pan-species antibody to combine the specific recognition of a major target (most often P.falciparum) and also allow the more general recognition of all malaria species.
Use in malaria testing
Both these antigens have similar characteristics in malaia testing and have the potential to detect any species. This makes them ttractive in diagnostic tests. However, although they offer good sensitivity for the recognition of ‘’P.falciparum’’ and ‘’P.vivax’’ they are is less effective in the detection of other species (particularly when parasite concentration is low).
The value of combination tests including a pan-malarial antigen is:
(1) Extended specied recognition: the ability to detect species not targetted by the species-specific antibody.
(2) Improved sensitivity: if the species-specific antibody gives a false negative result (for example HRP2 gene deletion or prozone effect (see test interpretation) then the pan-malarial antibody may still allow the infection to be detected.
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