title: Plasmodium malariae-infected erythrocytes in the peripheral blood, liver, stomach and duodenum: an ultrastructural study.
abstract: We examined the ultrastructure of Plasmodium malariae-infected erythrocytes in peripheral blood and tissue biopsies of the liver, stomach, and duodenum from three patients infected with P. malariae. Ultrastructural features of P. malariae-infected erythrocytes in peripheral blood appear similar to those described previously. The surface membranes of P. malariae-infected erythrocytes had numerous knobs, as seen in P. falciparum-infected erythrocytes. There was no evidence of P. malariae-infected erythrocytes in the microvessels of the organs. This finding suggests the presence of knobs on P. malariae-infected erythrocytes is not associated with the attachment of P. malariae-infected erythrocytes to vascular endothelium and may be the reason for the mild symptoms of malariae malaria. The failure to find P. malariae-infected erythrocytes in the tissue biopsies using electron microscopy may be due to low parasitemia. More cases with higher parasitemia need to be studied to confirm these findings.
authors: Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors: Emsri
authors: E
authors: Pongponratn
authors: Oranan
authors: O
authors: Prommano
authors: Urai
authors: U
authors: Chaisri
authors: Parnpen
authors: P
authors: Viriyavejakul
authors: Polrat
authors: P
authors: Wilairatana
mesh_terms: D000293:Adolescent; D000328:Adult; D004386:Duodenum / Q000469:parasitology*; D004912:Erythrocytes / Q000469:parasitology / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D008099:Liver / Q000469:parasitology*; D008288:Malaria / Q000175:diagnosis* / Q000469:parasitology; D008297:Male; D008854:Microscopy, Electron; D018512:Parasitemia / Q000469:parasitology*; D010965:Plasmodium malariae / Q000648:ultrastructure*; D013270:Stomach / Q000469:parasitology*