How benign is benign tertian malaria?

This retrospective study was conducted to determine the incidence of various complications of Plasmodium vivax malaria based on review of case records.

The case records of all confirmed cases of malaria over the period of one year (September 2005-August 2006) were studied. Complete blood count, peripheral blood findings, liver and kidney functions were reviewed. The results of rapid diagnostic test for malaria (OptiMAL test, Diamed AG, Switzerland) were correlated with the peripheral blood smear findings in the patients in whom it was requested. All abnormal results like a positive direct Coomb's test were noted. Findings were clinically correlated.

There were 265 confirmed cases by peripheral blood examination. Of these 221 were due to Plasmodium vivax and 41 due to P. falciparum. Two cases had mixed infection and in one case the species could not be identified as it showed only malarial pigment. The peak incidence of malaria was seen in September 2005 and August 2006. The complications in P. vivax were thrombocytopenia, biochemical evidence of hepatic dysfunction, renal damage, positive DCT and death due to ARDS. Thrombocytopenia was seen in 213 patients with counts < 20 x 103/microl in 13 patients. Nine (4%) patients had serum bilirubin >3 mg/dl with normal liver enzymes. Liver enzymes were elevated in 60 patients with seven patients showing liver enzymes level, three times the normal. Renal dysfunction was seen in 17 patients with serum creatinine ranging from 1.3-10.65 mg/dl. One patient went into acute renal failure following quinine therapy and showed red cell fragments in the peripheral blood. In two children DCT was positive with the peripheral smear showing RBC agglutinates around the parasitised RBC. There were three maternal deaths at about 32 weeks gestation due to ARDS. The peripheral blood smear in these patients showed WBC agglutinates.

This paper is presented to highlight that P. vivax malaria though considered to be a benign entity can also have a severe and complicated course which is usually associated with P. falciparum malaria.