The Microscopic Diagnosis of Malaria

      Skip to Main Content

HOME

HELP

.

BACK

Glossary

 

- A

Accolé:   a term applied to the manner in which the ring stage of Plasmodium attaches to the membrane of erythrocytes.

Amoeboid: resembling an amoeba, specifically by moving or changing shape through the flow of protoplasm.

Anopheles: a genus of mosquito, some species of which can transmit human malaria.

Artifact: an object on a stained smear that can be mistaken for a parasite but is of host origin or contamination.

 

- B

Babesia microti: a tick-borne blood parasite of rodents that can infect humans. Closely resembles Plasmodium but has only trophozoite forms in the blood.

Basophilic: staining readily with a basic stain, and acquiring a blue color.

Binucleate:   having two nuclei.

Borrelia sp: insectborne, spiral, filamentous bacteria that cause relapsing fever in humans.

 

-C  

Chromatin: a complex of a nucleic acid with basic proteins in eukaryotic cells that is usually dispersed in the interphase nucleus and condensed into chromosomes in mitosis and meiosis.

Crenated:   having the margin or surface cut into rounded scallops.

Cytoplasm:   the organized complex of inorganic and organic substances external to the nuclear membrane of a cell and including the cytosol and membrane-bound organelles (as mitochondria or chloroplasts).  

 

- E -

Erythrocyte: a red blood cell.

Erythrocytic stage: stage in the lifecycle of the malaria parasite found in red blood cells.

Exflagellation:   formation and extrusion of sperm-like microgamete from macrogametocytes composed of chromatin and flagella.

Exoerythrocytic stage: stage in the life cycle of the malaria parasite found in liver cells (hepatocytes).

 

- G

Gametocyte: the sexual stage of malaria parasites.

Giemsa stain:   stain consisting of a mixture of eosin and methylene azure used chiefly in differential staining of blood films.

 

- H

Helicosporium griseum: a fungus whose filamentous spores occasionally contaminate blood films and may be mistaken for microfilariae.

 

- J

Jamess dots: coarse basophilic dots in the cytoplasm of red cells infected with Plasmodium ovale

 

- L

Leukocyte: a white blood cell.   Also known as leucocyte.

 

- M

Macrogametocyte: female form of the gametocyte

Malaria: a mosquito-borne disease caused by a parasite

Maurers dots: organelles in the cytoplasm of red cells infected with P. falciparum. They are of parasite origin and may be involved in protein transport from host cell membrane to parasite.

Microgametocyte: male form of the gametocyte.

Monocyte: a leukocyte with a large, usually kidney-shaped nucleus. Within tissues, monocytes develop into macrophages which ingest bacteria, dead cells, and other debris.

Merozoites: stage in the life cycle of the malaria parasite, Plasmodium. Formed during the asexual division of the schizont. Merozoites invade other cells upon release.

Microfilaria: the larva of a filarial worm found in blood or tissue.

Morphological: relating to shape or appearance.

 

- N

Nucleus: the organelle within the cell that contains its genetic material (see also, chromatin).

 

- O

Ookinete: the motile zygote of the malaria parasite that penetrates the wall of the mosquito stomach to form an oocyst.

 

- P

Parasite: any organism that lives in or on another organism without benefiting the host organism; commonly refers to pathogens, most commonly in reference to protozoa and helminths.

Phagocyte: a type of white blood cell that can engulf and destroy foreign organisms, cells and particles. Phagocytes are an important part of the immune system.

Plasmodium: genus of the parasite that causes malaria; includes four species that infect humans: Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale and Plasmodium malariae.

Platelets: small, irregularly-shaped bodies in the blood that contain granules; important components of the blood coagulation (clotting) system.

 

- S

Schizont: developmental form of the malaria parasite that contains many merozoites; seen in liverstage and bloodstage parasites.

Schüffners dots: fine basophilic granules seen in the cytoplasm of red cells infected with Plasmodium vivax

Spirochetes: any bacterium of the order Spirochaetales, including those causing syphilis and relapsing fever, so called because of their spiral or corkscrew shape.

Stippling: having dots

 

- T

Trophozoite: a developmental form of malaria parasite in the bloodstage, or the feeding stage.   After merozoites have invaded red blood cells, they develop into trophozoites. Early trophozoites are sometimes called rings, or ring stage parasites. Trophozoites develop into schizonts.

 

- U

Uninucleate: having a single nucleus

 

-V

Vacuole:   a cavity or vesicle containing fluid in the cytoplasm of a cell.

 

-W

Wuchereria bancrofti: a mosquito-borne nematode that lives in the lymphatic system of infected humans whose larvae can be found in the blood.

 

-Z

Ziemanns dots: irregularly shaped dots seen in the cytoplasm of red cells infected with Plasmodium malariae.