Cytokines and clinical manifestations of malaria in adults with severe and uncomplicated disease.

Pro- and anti-inflammatory cytokines are supposed to be involved in malaria pathogenesis. Their relationship with clinical manifestations of the disease, however, is rarely studied in adults from non-endemic countries with imported disease, particularly with severe malaria. In this study we compared serum levels of gamma interferon (IFNgamma) and interleukins: IL-12, IL-18, IL-10 in healthy adults and patients with severe or uncomplicated imported malaria, with predominance of Plasmodium falciparum and Plasmodium vivax infections within studied group. Severe malaria was shown to be associated with elevated serum levels of IFNgamma and IL-18 as well as with relative deficiency of IL-12 mediated response in comparison to uncomplicated malaria cases, while IL-10 was found to be higher in all malaria patients compared to the controls. Overall, the results of our study are consistent with the observations from the regions with holoendemic malaria transmission, suggesting a pivotal role of impaired IL-12 expression in severe malaria. On the contrary, patients with severe malaria included into our study presented with the pattern of excessive production of inflammatory IFNgamma and IL-18, what seems to be an unusual finding compared to the results of the studies on African children and may be the feature of severe malaria in non-immune adults.