[Investigation of Molecular Differences in Plasmodium spp. Isolates Obtained from Malaria Patients].

Abstract

Malaria continues to pose a serious threat to more than half of the world’s population each year. The Plasmodium parasites that cause disease are not limited to humans alone; they have a wide range of infections that extend to reptiles, birds, mammals and other vertebrates. Plasmodium species have extraordinary genetic flexibility that allows them to adapt to changes in the environment, giving them the potential to rapidly develop resistance to therapeutics such as antimalarials and to change host specificity. Parasites multiply dynamically in the erythrocytes of vertebrate hosts and during the development of these parasites, numerous reactive oxygen species are produced that damage biological macromolecules in the cell. The severe form of malaria, cerebral malaria caused by Plasmodium falciparum, is a complex neurological syndrome. Survivors have behavioral difficulties, cognitive deficits and a risk of epilepsy. Cerebral malaria is associated with multiple organ dysfunction. Adhesion and accumulation of infected erythrocytes, platelets, and leukocytes (macrophages, CD4+ and CD8+ T cells and monocytes) in the cerebral microvessels play a major role in disease progression. Microvascular obstruction with coagulation and endothelial dysfunction contribute to neurological damage and disease severity. The aim of this study was to investigate the molecular differences of Plasmodium spp. isolated from imported and domestic patients diagnosed with malaria in the routine diagnostic laboratories of the Erciyes University Faculty of Medicine Department of Medical Parasitology. Thin smears were prepared from the peripheral blood of patients who applied to our hospital with the complaints of fever, shivering and chills, stained with Giemsa and examined under a microscope with a x100 objective. When the thin smears of the patients were examined, trophozoites and gametocytes belonging to the Plasmodium genus were detected. As a result of routine microscopic examination and molecular probe-based quantitative realtime polymerase chain reaction (qRt-PCR) studies for species identification, the Plasmodium spp. that infected the patients were identified. Of the 17 Plasmodium spp. isolates included in the study, 10 were P.falciparum, five were Plasmodium vivax, one was Plasmodium ovale and one was Plasmodium knowlesi. DNA sequence analysis was applied to the PCR products obtained as a result of conventional PCR studies targeting mitochondrial COX-1 gene regions for P.vivax and P.falciparum and 18S rRNA gene regions for P.ovale and P.knowlesi. DNA sequencing results were evaluated by BLAST analysis and phylogenetic analysis with the MEGA program. The data obtained were found to be compatible with similar isolates previously entered into Genbank by BLAST search. Malaria is one of the leading causes of death from infectious diseases. When malaria control programs are evaluated within eradication studies, it is thought that revealing the existing species and their molecular diversity is extremely valuable in terms of forming the basis of important studies such as vaccine, drug and resistance studies.