Diagnosis of intestinal amebiasis using salivary IgA antibody detection.

Attempts were made to use soluble antigen extract of strain HK-9 of Entamoeba histolytica to detect salivary IgA antibodies in intestinal amebiasis patients by using ELISA. Total salivary samples of 109 individuals were divided into four groups. Group I comprised 32 patients whose stools were positive only for E. histolytica cysts and/or trophozoites. Group II comprised 12 individuals whose stools were positive for E. histolytica and other intestinal parasites. Group III comprised 36 individuals whose stools were negative for E. histolytica but contained other intestinal parasites such as E. coli, E. nana, Blastocystis hominis, Trichomonas hominis, Giardia lamblia, Opisthorchis viverrini, and hookworm. Group IV comprised 29 healthy individuals whose stools were free from any intestinal parasitic infections. Based on the mean optical density, OD + 2SD of the results from 29 parasitologically negative healthy individuals, the cut-off OD value for salivary IgA antibodies was 1.265. Therefore, the assays were positive in 14 out of 32 (43.75%) of group I and 2 out of 12 (16.6%) of group II. The assays were positive in 16 out of 36 (44.44%) for group III whereas 2 out of 29 (6.90%) for group IV were positive. The overall sensitivity and specificity of the assays were 36% and 72%, respectively. The false positive rate was 28% and the false negative rate was 64%. The predictive values of positive and negative results were 47% and 63%, respectively. The diagnostic accuracy of ELISA for the presence of salivary IgA antibodies was 58%.

Prevalence of parasitic infections in Thai workers from 1993 to 1997.

Study on the prevalence of parasitic infections in Thai laborers who applied for working abroad was carried out during 5 years. The total number of 78,240 stool specimens was obtained and examined by simple smear and iodine. It was found that the prevalence of parasitic infections from 1993 to 1997 was 12.15%, 13.13%, 12.57%, 4.62% and 5.76% respectively. The five most frequently parasites found in stool were Blastocystis hominis, hookworms, Giardia lamblia, Strongyloides stercoralis and Opisthorchis viverrini. Such findings were similar to previous reports, but in lower percentages. Thus, continuity of public health education and sanitation improvement should be concerned for prevention and control of parasitic infections.

Prevalence of intestinal parasites in fresh vegetables and food-handlers of faculty of medicine Siriraj Hospital.

Studies on the prevalence of intestinal parasitic infections in food-handlers and fresh vegetables of the Faculty of Medicine Siriraj Hospital were carried out in November-December, 1987. The total number of 142 stool specimens and 105 nail specimens were collected and examined. In was found that the prevalence of parasitic infections and Enterobius vermicularis that would be directly transmitted from the food handlers to the consumers were found. Rhabditis spp. was only parasite found in fresh vegetables. Routine stool examination, personal hygiene, prevention and treatment of infected persons were suggested for the prevention of parasitic infections.

Treatment of Opisthorchiasis viverrini in hamsters with albendazole.

Efficacy of many drugs against Opisthorchis viverrini in man were shown by the percentages of egg reduction and the absence of egg in faeces. In some cases, however, the eggs reappeared after a period of time. The pathological changes of the bile duct could cause partial or even complete obstruction of the bile passages, thus resulting in the occurrence of natural egg reduction. Albendazole, a broad spectrum anthelmintic was used to treat opisthorchiasis viverrini in hamsters. At dosage of 100 mg per kg body weight twice daily for three consecutive days, the drug yielded an average of 81.5% of worm reduction at four months after medication. In this study complete cure was not obtained.