Prognostic implication of hypocalcemia and QTc interval in malaria

Hundred confirmed cases of malaria were included in the present study to determine the clinical and prognostic implications of hypocalcemia and corrected QT interval (QTc) prolongation in malaria. Peripheral blood smear examination was done to determine the parasite species and the parasite load. Serum calcium level and QTc measurements in electrocardiogram were done for each patient. Fifty patients were of P. falciparum malaria (38 complicated and 12 uncomplicated), 40 of vivax malaria and 10 patients were having mixed (P. falciparum and P. vivax) infection. Hypocalcemia was found in 26 cases in which QTc was prolonged. Ten patients who had convulsions, all of them were having QTc prolongation and eight had hypocalcemia. A total number of eight patients had muscle spasm, of which six had QTc prolongation and four had hypocalcemia. There were 34 cases of cerebral malaria, of which 18 had hypocalcemia as well as QTc prolongation, 12 of them developed renal failure and 14 had high parasitaemia. Four patients died who had hypocalcemia and QTc prolongation due to hepatorenal syndrome. The mean parasite load, QTc interval and serum calcium were 2.69 +/- 1.0, 0.468 +/- 0.055 sec and 8.16 +/- 0.86 mg/dl respectively in complicated falciparum malaria; 1.6 +/- 0.55, 0.442 +/- 0.043 sec and 8.72 +/- 0.97 mg/dl in complicated mixed (Pf + Pv) infection. 1.33 +/- 0.52, 0.435 +/- 0.035 sec and 9.77 +/- 1.34 mg/dl in uncomplicated falciparum malaria and 1.35 +/- 0.58, 0.403 +/- 0.019 sec and 9.68 +/- 0.99 mg/dl in vivax malaria. The difference was significant between complicated falciparum and mixed (Pf + Pv) infection when compared to uncomplicated falciparum and vivax malaria (p < 0.05).