Abstract
Background For years, Plasmodium vivax has been considered the cause of benign malaria. Nevertheless, it has been observed that this parasite can produce a severe disease comparable with Plasmodium falciparum. It has been suggested that some physiopathogenic processes might be shared by these 2 species, such as cytoadherence.
Objective This study was conducted to demonstrate the severity of the disease with the hyaluronic acid (HA) level with different species of Plasmodium in patients complaining of fever of unknown origin, highly suspected clinically to be caused by malaria, which were diagnosed by microscopic examination, OptiMAL rapid antigen test, and serum level of HA and were assessed.
Subjects and Methods A total of 32 expatriate patients attending King Faisal Specialized Hospital, Taif, Kingdom of Saudi Arabia, complaining of fever of unknown origin were examined for malaria parasites by microscopy of Giemsa-stained blood smears, OptiMAL rapid antigen test, and HA test. The diagnostic performance of these methods was statistically compared.
Results Of 32 clinically suspected cases, 17 (53%) were positive for Plasmodium infection, and of these, 8 (47%) were infected by P. falciparum (G1) and 9 (53%) by P. vivax (G2). Fifteen (47%) were negative for Plasmodium species (G3). The differences in the level of HA were statistically significant in G1 as compared with G3 as well as G2 as compared with G3 and statistically insignificant in G2 as compared with G1 (P > 0.05).
Conclusions The association of severity of anemia and the trend observed between adhesion to HA and increased parasite densities suggest their potential contribution to sequestration observed in P. vivax infections.