The haematological emergency - Malaria - Calendar 2008 month 12

Author(s): H. Diem (1), R. Hinzmann, F. Forstreuter (2)
Institution(s): (1) Würmtal-Labor, 82131 Gauting; (2) Sysmex Europe GmbH, Norderstedt - Germany
References: The Sysmex Scientific Calendar 2008;
Photos and text: Heinz Diem, MD; text: Rolf Hinzmann, MD, PhD; Frauke Forstreuter, PhD
Last change of this image collection: 2008/01/01

If malaria is suspected, so called 'thick blood films' have to be prepared by the laboratory. Additional regular blood films are required because the thick blood film does not always allow the differential diagnosis of the Plasmodium species (the plasmodia can be damaged by the haemolysis). The diagnosis of malaria is quite often an incidental finding and must be reported to the physician immediately.

A ‘thick blood film’ is prepared by spreading a drop of blood on a slide in a way that approximately 20 layers of erythrocytes are on top of each other. The slide is then left to dry and subsequently treated with Giemsa solution to lyse the erythrocytes. This process leads to a higher density of the malaria pathogens (here: trophozoites of Plasmodium falciparum <-) on the slide so that they can be detected more easily and quickly. The large nuclei are debris from lysed leukocytes.

Several throphozoites (Tr) in a patient with in malaria tropica. Concomitant thrombocytopenia with giant platelets (T).

The same patient as above: At higher magnification the nucleus of the malaria parasite (reddish dot) and the digestive vacuole (bluish ring) are clearly visible.