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.

Can treatment of P. vivax lead to a unexpected appearance of falciparum malaria?

Of 994 patients admitted to the Bangkok Hospital for Tropical Diseases for P. vivax malaria, 104 (10.5%) experienced appearance of Plasmodiumfalciparum following drug treatment for P. vivax . In all patients, P. falciparum parasites were not found by microscopic examination upon admission. The mean time for P. falciparum appearance was 12.6 days after the commencement of chloroquine treatment. Patients experiencing appearance of P. falciparum had significantly lower hematocrit, and greater initial P. vivax parasite counts. We use a mathematical model to explore the consequences of chloroquine treatment of such mixed infections. Both clinical results and features of the model suggest that such "hidden infections" may be quite common, and that the appearance of P. falciparum may be stimulated by treatment of P. vivax.

Effects of rice powder salt solution and milk-rice mixture on acute watery diarrhea in young children.

A randomized pilot study was carried out to compare the safety and effectiveness of rice powder salt solution (RPSS) in combination with milk-rice mixture (RPSS-MR group, n = 17) with other two regimens, glucose-based oral rehydration solution (ORS) combined with MR (ORS-MR group, n = 17) and ORS combined with formula milk (ORS-milk group, n = 14) in the treatment of acute watery diarrhea with mild to moderate dehydration in 48 boys younger than 2 years. Results showed that in the first 24 hours patients in the RPSS-MR group had significantly smaller amounts of stool weight (32.7 g/kg) than those in the ORS-MR group (67.5 g/kg) and ORS-milk group (59.2 g/kg) (p< 0.05 for both measurements). Patients in the RPSS-MR group also had significantly shorter duration of diarrhea (29.6 hours) than the other two groups (43.8 hours and 49.6 hours, respectively) (p < 0.05 for both measurements). The stool weight and duration of diarrhea between the ORS-MR group and the ORS-milk group were not significantly different. The positive effect of milk rice mixture was not demonstrated in the study due to the significantly more severe diarrhea in the ORS-MR group. The effectiveness of the RPSS-MR is therefore likely due to mainly RPSS.

Incidence and clinical manifestations of influenza in nurse assistant students.

A prospective study was conducted to find the incidence and clinical manifestations of influenza in 201 nurse assistant students of Faculty of Tropical Medicine during June 1998 to May 1999. There were 106 episodes of influenza-like illness (incidence 52.7%) of which only 33% were proven to be influenza (incidence 17.4%). Main clinical manifestations of influenza included headache, fever, malaise, myalgia, rhinorrhea, cough, and sore throat. We found that influenza could not be diagnosed solely by using clinical manifestations. Respiratory pathogenic bacteria were rarely isolated in patients with influenza-like illness and this led to our suggestion that routine pharyngeal culture and antibiotic therapy would not be helpful. Influenza vaccination of every nurse assistant student would be beneficial.

Pleural effusion in childhood falciparum malaria.

Pulmonary complication is a rare manifestation of childhood malaria and isolated pleural effusion without pulmonary edema has never been reported in children. We report here an 11-year-old boy who suffered from cerebral malaria and massive right pleural effusion. The patient was treated with intravenous artesunate, albumin, and other supportive treatments. He recovered completely after eight days. The clinical and laboratory courses suggested that the plasma leakage played a role in the pathogenesis of pleural effusion.

Dengue infection with unusual manifestations: a case report.

Since 1978, there has been an increasing number of reported cases of dengue infection with unusual manifestations and most of them had dengue shock syndrome. We report here one patient who had dengue hemorrhagic fever grade II with liver failure and hepatic encephalopathy and very high elevation of liver enzymes. She made a complete recovery after conservative therapy. She is the fourth case of reported dengue hemorrhagic fever grade II who had unusual manifestation.

Randomized dose-ranging study of the safety and efficacy of WR 238605 (Tafenoquine) in the prevention of relapse of Plasmodium vivax malaria in Thailand.

WR 238605 is an 8-aminoquinoline developed for the radical cure of Plasmodium vivax. Forty-four P. vivax-infected patients were randomly assigned to 1 of 4 treatment regimens: 3 groups received a blood schizonticidal dose of chloroquine followed by WR 238605: group A (n=15) received 300 mg daily for 7 days; group B (n=11), 500 mg daily for 3 days, repeated 1 week after the initial dose; group C (n=9), 1 dose of 500 mg. A fourth group (D; n=9) received chloroquine only. Among patients who completed 2-6 months of follow-up (n=23), there was 1 relapse in group B (day 120) and 1 in group C (day 112). Among patients treated with chloroquine only, there were 4 relapses (days 40, 43, 49, and 84). WR 238605 was safe, well tolerated, and effective in preventing P. vivax relapse.

Treatment of malarial acute renal failure by hemodialysis.

We studied 112 patients with malarial acute renal failure (ARF) during the period 1991-1997 at Bangkok Hospital for Tropical Diseases (Mahidol University, Bangkok, Thailand). Hemodialysis was performed in 101 (90.2%) of these patients. The mean number of times the patients were hemodialyzed was 6.5 (range = 1-27). Ninety-three (83.0%) patients were oliguric and the remainder were nonoliguric. Patients who had oliguric renal failure required more hemodialyses and had more complications than the nonoliguric patients. The oliguric patients had an eight-fold higher risk of requiring six or more hemodialyses (95% confidence interval = 1.2-53.9, P = 0.0008). The overall mortality rate was 10.7% (12 of 112). Eleven of the patients who died were jaundiced and eight of them had cerebral malaria with a Glasgow Coma Score < or = 8. We conclude that hemodialysis is a useful treatment for oliguric and nonoliguric ARF from severe malaria, particularly when initiated early in the course of the illness.

A randomized, double-blind, comparative trial of a new oral combination of artemether and benflumetol (CGP 56697) with mefloquine in the treatment of acute Plasmodium falciparum malaria in Thailand.

CGP 56697, a new oral fixed combination of artemether and benflumetol, was tested in a double-blinded, randomized trial in 252 adult patients treated either with CGP 56697 (4 x 4 tablets each containing 20 mg of artemether and 120 mg of benflumetol, given at 0, 8, 24, and 48 hr), or with mefloquine (three tablets of 250 mg at initial diagnosis, followed by two tablets of 250 mg at 8 hr). Baseline data of the two groups were comparable. The 28-day cure rate with CGP 56697 was lower than with mefloquine (69.3% versus 82.4%; P = 0.002). However, CGP 56697 was more effective than mefloquine in parasite clearance time (43 hr versus 66 hr; P < 0.001) fever clearance time (32 hr versus 54 hr; P < 0.005), and gametocyte clearance time (152 hr versus 331 hr; P < 0.001). This study revealed that CGP 56697 is effective against multidrug-resistant Plasmodium falciparum malaria in Thailand, but higher doses will probably be needed to improve the cure rate.

Research on new antimalarial drugs and the use of drugs in combination at the Bangkok Hospital for Tropical Diseases.

With the emergence of multidrug resistant falciparum malaria in Thailand, various approaches have been taken. Research on new antimalarial drugs and the use of existing available drugs with modification are urgently needed. New drugs and drugs in combination such as pyronaridine, WR 238605, arteether, dihydroartemisinin, benflumetol atovaquone/proguanil are being evaluated. Drug combinations for the treatment of patients suffering from uncomplicated falciparum malaria include quinine-tetracycline for 7 days, or sequential treatment of artesunate (600 mg given over 5 days) followed by mefloquine (1,250 mg divided into 2 doses 6 hours apart) are recommended. The sequential treatment is highly recommended for those who failed other treatment regimens. Other combinations such as a short course sequential treatment of artesunate (300 mg given over 2.5 days) followed by a single dose of 750 mg mefloquine, or a combination of mefloquine 1,250 mg together with tetracycline 1 g per day or doxycycline 200 mg per day for 7 days are alternative treatment regimens with acceptable cure rates. The simultaneous administration of artesunate and mefloquine, in various doses and duration of treatment, is currently being investigated. Until proven otherwise, the drug combinations are still recommended for all adult patients suffering from acute uncomplicated falciparum malaria contracted in multidrug resistant areas. In severe malaria and malaria in children, the drug combinations need further investigation.

A clinical trial of combination of artesunate and mefloquine in the treatment of acute uncomplicated falciparum malaria: a short and practical regimen.

The difficulties in treating drug-resistant falciparum malaria in Thailand are compounded by the necessity of giving antimalarials over long periods of time. The resultant fall in patient compliance not only lowers cure rates but also predisposes to the further spread of drug-resistance. Sequential treatment with artesunate given over 5 days followed by mefloquine produced 100% cure rates in previous study, but might not be a suitable regimen for field treatment. We conducted a clinical trial of a combination of artesunate and mefloquine given twice daily for 2 days in 150 patients with acute uncomplicated falciparum malaria. The dose of artesunate (200 mg) and mefloquine (312.5 mg) were given simultaneously in a separate package. All patients were admitted to a hospital in Bangkok for 28 days to exclude re-infection and monitor the possible adverse effects. One hundred and thirty patients completed the study with 28 days follow up. Twenty patients (13%) left the hospital prior to completion of follow-up for reasons unrelated to their treatment. Cure rate was 97% (126/130). There were no RII or RIII failures and all four patients with treatment failures were of the RI type. The mean parasite clearance time and fever clearance time were 46.4 and 42.5 hours, respectively. All patients were tolerated the combination drugs well and there were no serious toxic adverse reactions. The results indicate that combination of artesunate and mefloquine given twice daily for 2 days is effective and well tolerated in patients with acute, uncomplicated falciparum malaria and suitable as an alternative treatment for multidrug resistant falciparum malaria.