Plasma retinol and alpha-tocopherol level and growth indices of 7 months old healthy Thai infants in Bangkok.

A cross-sectional study was conducted to measure plasma retinol and alpha-tocopherol status and the growth indices of 66 healthy Thai infants aged about 7 months old. The mean (SD) plasma retinol and alpha-tocopherol level were 1.59(0.31) and 25.40(7.01) micromol/l respectively. For their weight, height, and body mass index, the mean (SD) values were 7.96(0.93) kg, 69.95(2.42) cm, and 16.25(1.43) respectively. There was a remarkable proportion of improper feeding. However there were no correlations between plasma retinol level, plasma alpha-tocopherol level, growth indices and duration of breast milk, formula milk, weaning food feeding except alpha-tocopherol level which positively correlated with duration of breastfeeding.

Pharmacokinetics of primaquine in healthy volunteers.

The pharmacokinetics of primaquine were investigated in 8 healthy subjects (4 males and 4 females). The volunteers received 15 mg base of primaquine daily for 14 days. The results showed that the concentration-time profiles in whole blood and in plasma were similar. The mean values (+/- SD) of area under the curve (AUC) of the last dose were significantly decreased when compared to the values of the first dose both in whole blood and in plasma (909.96 +/- 603.07, 1,147.05 +/- 684.8 ng.hr/ml respectively in whole blood with p = 0.007 and 1,255.11 +/- 531.59, 1,603.66 +/- 505.45 ng.hr/ml respectively in plasma with p = 0.023). The decrease in the concentration-time profile of the last dose was due to enhancement of drug elimination with significant increase in clearance after the last dose (4.871 +/- 1.741 and 6.443 +/- 2.514 ml/min/kg respectively in whole blood with p = 0.007, 3.199 +/- 1.197 and 4.422 +/- 2.068 ml/min/kg respectively in plasma with p = 0.016).

Treatment of quinine resistant falciparum malaria in Thai children.

A study was carried out to assess the efficacy of a modified 7 day course of quinine in children with falciparum malaria, in comparison with those of a 7 day course of quinine at standard dosage and a combination of a 7 day course of quinine and sulfadoxine-pyrimethamine, and in relation to the MIC, and to the serum levels of quinine during the course of treatment. Seventy seven children aged 2 years to 12 years with falciparum malaria were randomly treated with one of the 3 regimens. Group I, quinine 10 mg base per kg body wt. 8 hourly for 7 days, 21 of 28 cases (75%) were cured, while 6 cases (21%) showed RI and 1 case (4%) RII failure. Group II, quinine 10 mg base per kg body wt. 8 hourly for the first 4 days then 15 mg base per kg body wt. 8 hourly for the next 3 days, 20 of 23 cases (87%) were cured, while 3 cases (13%) showed RI failure. Group III, quinine 10 mg base per kg body wt. 8 hourly for 7 days and then sulfadoxine 30 mg per kg body wt. and pyrimethamine 1.5 mg per kg body wt., 16 of 26 cases (62%) were cured and 10 cases (38%) showed RI failure. The cure rates in the 3 groups were not statistically different. The three groups had similar serum quinine concentration profiles. Treatment with quinine was successful in cases in which serum quinine levels could be maintained above MIC for 7 days. There was no additional effect of sulfadoxine-pyrimethamine on quinine.

Serum quinine concentrations following the initial dose in children with falciparum malaria.

Serum quinine concentrations were determined in 51 children with uncomplicated falciparum malaria and 22 controls. Quinine 10 mg salt/kg was given one-hour, two-hour, four-hour intravenously in group A (14 patients, 5 controls), group B (12 patients, 6 controls), Group C (10 patients, 6 controls) and given orally in group D (15 patients, 5 controls). In malaria patients, the highest serum quinine levels were observed at the end of intravenous infusion and by the 4th hour after oral medication. Mean of the peaks of the drug concentrations of the 4 schedules were not significantly different, ranging from 22 to 28 n mol/ml. Serum concentrations in the patients were significantly higher than those of the controls. The total clearance of quinine in the patients were approx. 1 ml/min/kg, which was significantly less than those of the controls. The total apparent volume of distribution of the drug was similarly reduced. In patients it was about 0.8 litre/kg. The elimination half times of quinine ranged from 9 to 11 hours, whereas the value in the controls ranged from 3 to 7 hours. Side effects of quinine were not observed.

Red cell acetylcholinesterase activity in Plasmodium falciparum malaria.

Red cell ACHE activity was determined in 19 patients with P. falciparum malaria, 13 patients during convalescence as well as in 6 normal subjects. There was no significant difference between the mean values of ACHE in red cells of these 3 groups. After separation these blood samples into 2 portions by centrifugation in 5% Ficoll solution, the parasitized red cells in the lower portion which are mostly ring forms contained the same amount of ACHE activity as those of the normal subjects and the non-parasitized red cells. However, the parasitized red cells in the upper portion which contained predominantly mature asexual forms revealed a significantly higher ACHE activity than those of the normal red cells. There was also a reverse relationship between red cell ACHE activity and the parasitaemia from this portion of blood sample. These findings indicated that although malarial parasite invaded and caused the red cell membrane damage, it did not inactivate ACHE. It may be concluded that ACHE was not responsible for the anaemia and excessive erythrocyte destruction in patients with P. falciparum malaria.

Treatment of giardiasis in children with quinacrine, metronidazole, tinidazole and ornidazole.

One hundred and twenty four children with symptomatic and parasitologically confirmed giardiasis were treated in a comparative trial. The dosage of antigiardia drug was adjusted to the body surface area of the patients from the adult basic dosage as 100 mg of quinacrine t.i.d. for 5 days, 200 mg of metronidazole t.i.d. for 7 days, 2 gm of metronidazole once, 2 gm of tinidazole once or 2 gm of ornidazole once. They were hospitalized for follow-up for 30 days. The parasitological follow-up consisted of daily examination of stool specimens. Reinfections were unlikely. The rates of success were: a 5-day course of quinacrine, cured all of them, 20 patients; a 7-day course of metronidazole, 12 of 20; metronidazole, single dose, 11 of 21; tinidazole, single dose, 18 of 21; ornidazole, single dose, 21 of 22; placebo, none of 20. After a single dose, 5 patients had transient elevation of transaminases, one patient in each of metronidazole and tinidazole group 3 patients in ornidazole group. A 5-day course of quinacrine gave excellent result but the drug is not widely marketed. Ornidazole or tinidazole were more effective, both of them were recommended as a drug of choice as single dose therapy, however transient increase of transaminases may occur in some cases.