Plasmodium falciparum: Morphology: Difference between revisions
From MalariaETC
No edit summary |
No edit summary |
||
| Line 52: | Line 52: | ||
*Additional blue/grey dots and clefts are seen in red cell cytoplasm when [[stained correctly]] | *Additional blue/grey dots and clefts are seen in red cell cytoplasm when [[stained correctly]] | ||
*These dots have low number a characteristic "dot" or "line" form [[Added dots main|Maurer's dots and clefts]] | *These dots have low number a characteristic "dot" or "line" form [[Added dots main|Maurer's dots and clefts]] | ||
*[[Red cell size and shape|Size and shape]] of infected red cells is usually unaffected, but may become crenated | *[[Red cell size and shape main|Size and shape]] of infected red cells is usually unaffected, but may become crenated | ||
*The [[Double chromatin dot forms|double dot]], [[Accolé form| accolé]], and [[multiple parasites|multiple parasite]] forms remain present | *The [[Double chromatin dot forms|double dot]], [[Accolé form| accolé]], and [[multiple parasites|multiple parasite]] forms remain present | ||
</br> | </br> | ||
Revision as of 11:47, 10 December 2024
| Navigation |
| >Main malaria Index |
| >Main Species identification page |
Morphology of Plasmodium falciparum
The early trophozoite
The earliest growth stage, this is characterised by fine ring forms with few other changes to red cell or parasite.
- Ring forms are fine and delicate and may be the sole form present (synchronicity)
- Frequently the red cells contain multiple parasites
- Parasites may have a distinctive "double dot" or signet ring form
- Parasites may appear on the accolé forms that appear flattened against the cell membrane
- Affected red cells have normal size and haemoglobin content
| The late trophozoite |
The early trophozoite
The later growth stage of trophozoites where parasites modification of the erythrocyte is seen with characteristic added dots and possible minor changes to red cell form:
- Parasites resemble early ring forms, but are thicker and may be slightly larger
- Additional blue/grey dots and clefts are seen in red cell cytoplasm when stained correctly
- These dots have low number a characteristic "dot" or "line" form Maurer's dots and clefts
- Size and shape of infected red cells is usually unaffected, but may become crenated
- The double dot, accolé, and multiple parasite forms remain present
| The schizont |
The schizont is the asexual form of the malaria parasite in blood - for a detailed description see the "Biology of malaria" section in the main menu:
- Do not generally circulate in this species unless overwhelming infection
- The merozoites cluster "untidily" as they develop
- Schizonts develop progressively to form 8-16 merozoites when mature
- In this species the loose malaria pigment may be seen in clumps between the parasites
- Red cell size is generally unaffected but red cells become pale as haemoglobin is metabolised by the parasites
→Click for P.falciparum schizont gallery
| The gametocyte |
The sexual replication form (very distinctive).
- male and femaie gametocytes are elongated and have the appearance of rods
- They parasites are rod shaped but the membrane may cause them to curve into a “"banana" form”
- The residual membrane (empty of haemoglobin) is often seen as a "blister" to the side of the parasite
- The single chromatin area is in the centre of the parasite, often has pigment overlying it
- Gametocytes may not be be seen, or may be the only form present (particularly after treatment)
→Click for P.falciparum gametocyte gallery