1. To assess the association between vitamin A, vitamin E and the clinical course of severe malaria, serial morning blood samples were taken from 24 Vietnamese patients, aged 18–62 years, receiving intensive treatment for complicated Plasmodium falciparum infections. A single fasting blood sample was also taken from 10 control subjects aged 22–45 years. Serum retinol, carotene and vitamin E concentrations were measured by h.p.l.c.
2. Admission serum retinol concentration was depressed relative to that of the control subjects (0.69 ± 0.35 versus 1.86 ± 0.41μmol/l mean ± SD, P < 0.001) and correlated inversely with indices of hepatic function, but positively with the simultaneous serum creatinine concentration (P < 0.05). During the first week of treatment, serum retinol concentration increased in parallel with improving liver function, whereas serum creatinine concentration remained elevated in the majority of patients. Serum α- and β-carotene concentrations remained depressed throughout.
3. Serum vitamin E concentration, corrected for total serum cholesterol concentration in the form of a ratio, was also depressed at presentation (3.1 ± 1.8×103 versus 4.2 ± 0.8×103 in control subjects; P < 0.05), but tended to be higher than the control value at the time of discharge (0.1 > P > 0.05); there was a significant correlation between admission ratio and parasite clearance time (P = 0.04).
4. On the basis of this and previous studies, vitamin A replacement could be considered in selected severely ill patients without renal impairment. As found previously in animal models, depressed vitamin E levels may have a beneficial effect on the course of malarial infection.
Vitamin A status of neonatal foals assessed by serum retinol concentration and a relative dose response test
