The efficacy and safety of 30 mg fexofenadine HCl bid in pediatric patients with allergic rhinitis.

Allergic rhinitis is one of the most common chronic disorders in children. It is also one of the most common causes of absence from school. This study reports on the efficacy and safety of a twice-daily oral dose of fexofenadine HCl 30 mg in Asian children aged 6-11 years diagnosed with seasonal or perennial allergic rhinitis. A total of 100 children with a history of allergic rhinitis for more than one year and a positive prick skin test response to at least one of the common aeroallergens in Thailand were enrolled in this multi-center, open-label, non comparative study. The severity of individual symptoms such as sneezing, rhinitis, etc. and adverse events were recorded in diary cards by the patients in form of scores as well as by the investigator at each visit. The total symptom score (TSS) with or without blocked nose at baseline, week 1 and week 2 was recorded. The TSS was defined as the sum of the individual symptom scores except for the nasal blockage score, as nasal blockage was not expected to respond to antihistamine treatment. Only patients with a total symptom score > or = 6 were included in the study. There was a statistically significant improvement at p < 0.01 for the TSS with or without blocked nose and for each symptom score such as blocked nose, sneezing, rhinorrhea, itchy nose/palate and/or throat, and itchy/watery/red eyes from baseline to week 1 and week 2. Additionally, there was a statistically significant improvement between week 1 and week 2 for itchy nose/palate and/or throat and itchy/watery/red eyes (p < 0.05). The Kappa measure of agreement was statistically significant at p < 0.001 between investigator's and patient's/parent's assessment, indicating the same degree of satisfaction with the overall effectiveness of the treatment. Fexofenadine 30 mg bid is effective in reducing the total symptom score of allergic rhinitis including blocked nose and is generally well tolerated. It is not cardiotoxic and is safe for pediatric patients as young as 6 years of age.

Plasmodium vivax malaria in Southeast Iran in 1999-2001: establishing the response to chloroquine in vitro and in vivo.

Chloroquine-resistant Plasmodium vivax is emerging in Oceania, Asia and Latin America. The drug sensitivity of P. vivax to chloroquine both in vivo and in vitro in the southern part of Iran was assessed; chloroquine-resistant Plasmodium falciparum has already been documented in this area. The in vitro sensitivity of 39 P. vivax isolates was assessed: the mean IC50 and IC90 were 189 ng/ml and 698 ng/ml blood respectively; for in vivo testing, all 39 vivax malaria patients were treated with a standard regimen of chloroquine and followed-up at 28 days: the mean parasite clearance time was 67.2 +/- 22.5 hours. The in vitro development of young parasites to mature schizonts in standard test medium was compared with that obtained in McCoy's 5A medium: no significant difference was observed. Synchronization of the blood-stage parasites was performed according to Lambros' method: the method was not suitable because it was detrimental to the parasites. A number of in vitro tests were performed using both our own laboratory-predosed microplates and WHO microplates: there was no significant difference between the results.

Normal plasma free amino acid levels in Thai children.

Analysis of plasma free amino acid levels is important for diagnosis of inborn errors of metabolism. Traditionally, this is performed using commercially available dedicated amino acid analyzers, but few such instruments are available in Thailand, and many are not used in routine operations. Here, the authors describe the analysis of plasma free amino acid levels in 57 normal children by reverse-phase HPLC and pre-column derivatization with phenylisothiocyanate. Plasma free amino levels are reported as mean +/- SD and 95 per cent confidence interval of mean for each of 5 age groups: 0-6 months; 6-12 months; 1-3 years; 3-6 years; 6-12 years. Mean amino acid levels were generally similar in all age groups (p > or = 0.01), except that hydroxyproline tended to be higher in the 0-6 months age group compared to other age groups (p<0.01). Comparisons were made between the present data with the normal free plasma amino acid levels in children of similar age groups reported both in Thailand and overseas in terms of both mean +/- SD and maximum and minimum values. Overall, our methodology involving HPLC can identify 35 amino acid derivatives, including all the major amino acids except for cysteine, which is substantially more than the number reported in earlier work on plasma free amino acid levels in normal Thai children. Moreover, the present methodology gives mean +/- SD values similar to an overseas report. For these reasons, HPLC should be considered as an alternative approach in laboratories, where demand does not justify the need for dedicated amino acid analyzers. However, there can be substantial variations between the results from different laboratories, and each laboratory should establish its own normal values.

Antiparasite adherence activity in Thai individuals living in a P. falciparum endemic area.

Two types of antimalaria antibodies in the serum of 54 villagers living in a malaria endemic area of Thailand were determined by indirect immunofluorescence assay in order to define the status of malaria immunity within the group. Antibodies to parasite-derived antigens in the membrane of ring stage-infected erythrocytes were very high (> or = 1:1,250) in 44%, moderate to low (< or = 1:250) in 37% of the sera, and the rest did not have the antibody. However, all the sera had antibodies to antigens of the intraerythrocytic mature parasites, showing a very high level in 65% and moderate to low levels in 37% of the sera. Sera with high antibody titers to either type of antigen significantly inhibited cytoadherence of P. falciparum-infected erythrocytes. All the sera variably inhibited rosette formation of the parasites but showed no association with the antibody titers. These results suggest that the antibodies to cytoadherence and rosette formation can be elicited and sustained in the malaria experienced host while living in the endemic area. This may be a natural preventive mechanism against the severity of P. falciparum infection in the infected host. How long the antiparasite adherence activity will last remains to be investigated.