Diagnostic Findings [Last Modified: ]
Malaria
[Plasmodium falciparum] [Plasmodium knowlesi] [Plasmodium malariae] [Plasmodium ovale] [Plasmodium vivax]
Causal Agent Life Cycle Geographic Distribution Clinical Features Laboratory Diagnosis Treatment

Ring-form trophozoites of P. malariae have one (rarely two) chromatin dots and a cytoplasm ring that tends to be thicker than P. falciparum.  'Bird's-eye' forms may appear. There is no enlargement of infected RBCs.

Plasmodium malariae ring-form trophozoites

A

A: Ring-form trophozoites of P. malariae.  Fig. 1: Normal red cell; Figs. 2-5: Ring-form trophozoites.
Illustrations from: Coatney GR, Collins WE, Warren M, Contacos PG. The Primate Malarias. Bethesda: U.S. Department of Health, Education and Welfare; 1971.

Plasmodium malariae ring-form trophozoite in thick blood smear Plasmodium malariae ring-form trophozoite in thin blood smear
B C

B: Ring-form (lower right) and developing (upper left) trophozoites of P. malariae in a thick blood smear.
C: "Birds-eye" trophozoite of P. malariae in a thin blood smear.

Plasmodium malariae ring-form trophozoite in thin blood smear Plasmodium malariae ring-form trophozoite in thin blood smear
D E

D, E: Ring-form trophozoites of P. malariae in thin blood smears.

 
Back Top