Plasmodium malariae: Morphology
From MalariaETC
| Navigation |
| >Main malaria Index |
| >Main Species identification page |
Plasmodium malariae
P. malariae infection overlaps geographically with the distribution of P.falciparum in areas that include sub-Saharan Africa, Southeast Asia, Indonesia, the western Pacific and in areas of the Amazon Basin of South America.
The early trophozoite
During this later growth stage the rings enlarge and begin to modify the erythrocyte, forming typical features of the species.
- Small but well-formed rings are typically seen sometimes with a central chromatin dot or elongation
- Red cells are generally of normal size, though occasionally may have reduced volume
- Pigment will not generally be present at this developmental stage
The late trophozoite
Text
- Parasites may be elongated, forming a band across the infected red cell
- Others spread to form an angular or basket form within the red cell
- Red cells remain round, but red cell size is often reduced
- cytoplasmic dots are uncommon but Ziemann's stippling may be seen
- Pigment can now be seen over the parasite surface
The schizont
Often present in the blood, these small schizont forms may have species-specific features.
- These are often seen in this species – the number of individual merozoites is often low (around 8)
- The central area of clumped pigment may have merozoites arranged to form a “daisy head” appearance
- At this stage the erythrocyte is devoid of haemoglobin and the small size is readily detected
The gametocyte
The sexual replication form in this species tend to be small beat and round.
- Gametocytes tend to be regular and round in shape.
- The parasites are small and do not generally fill the erythrocyte
- Haemoglobin is absent and scattered pigment overlies or surrounds the gametocyte