Clinical features of severe malaria:Protective effect of mixed plasmodial malaria

ABSTRACT

Objective: To investigate clinically severe malaria patients with Plasmodium falciparum (P. falciparum), Plasmodium vivax (P. vivax) and mixed species infections. Methods: This study was conducted at Dr. Saiful Anwar General Hospital, Malang, Indonesia, from December 2011 to May 2013. Twenty nine patients (mean age of 41 years, 22% female), who suffered from severe malaria according to World Health Or-ganization criteria (major and minor) and other criteria based on previous studies, were selected by consecutive sampling. Blood samples were obtained at admission from pe-ripheral blood for microscopic diagnostic, nested PCR and laboratory examination of blood chemistry. Laboratory results were compared between the groups and correlated to each other. Results: From 29 samples, eight (28%) were diagnosed as P. falciparum mono-infection, 12 (41%) as P. vivax mono-infection and nine (31%) as mixed infections, confirmed by PCR. Cerebral malaria occurred in P. falciparum or mixed species infection only. Para-sitaemia was highest in P. falciparum mono-infection. Mean haemoglobin was signifi-cantly lower in P. falciparum than P. vivax infection (P=0.01). Mean thrombocyte count (77 138/mL) was low in all groups. Mean urea, creatinine, total and direct bilirubin were significantly higher in P. falciparum mono-infection compared to other groups, whereas aspartate aminotransferase and alanine aminotransferase showed no significant differ-ences. Parasitaemia was positively correlated with an increase in urea, creatinine, bilirubin and leucocytosis in all species. Conclusions: Both Plasmodium species can solely or in combination cause severe ma-laria. Mixed infection was generally more benign than P. falciparum mono-infection and seemed to have some protective effects.