A comparison of metronidazole and single-dose ornidazole for the treatment of dientamoebiasis

Abstract

Recent reports of the pathogenic potential of Dientamoeba fragilis have underlined the need for an effective treatment against this colon-dwelling protozoan. Metronidazole is a well-known and commonly used anti-protozoal agent, but another 5-nitroimidazole derivative, ornidazole, may be preferable, where available, because of its longer half-life and fewer side-effects. This study compared the efficacies of metronidazole and ornidazole in a group of 112 patients with dientamoebiasis. Patients were randomised into two treatment groups: group 1 (n = 56) received metronidazole for 5 days, 20 mg/kg/day for children and 1.5 g/day for adults, in three oral doses, while group 2 (n = 56) received a single oral dose of ornidazole, 30 mg/kg for children and 2 g for adults. Stool samples were examined on the seventh and 14th days after treatment, and clinical symptoms were recorded to evaluate the efficacy of treatment. A statistically significant difference was recorded between the efficacies of ornidazole and metronidazole, both parasitologically (92.9% vs. 69.6%, p 0.001) and clinically (96.4% vs. 76.8%, p 0.001). Patients in the metronidazole group reported more side-effects than patients in the ornidazole group, none of whom required termination of treatment. These results suggest that single-dose ornidazole may be an important alternative agent for the treatment of dientamoebiasis.

Treatment of Dientamoeba fragilis in Patients with Irritable Bowel Syndrome

“…We used PCR for the detection of D. fragilis, which is known to be a sensitive method for detecting the parasite, 42 and we analyzed three consecutive samples thereby overcoming the problem with intermittent shedding of the parasite in feces. 43 Our eradication rate of 60% of MZ on D. fragilis is consistent with the literature 24,[43][44][45][46][47] supporting the validity of our estimate of microbiological response. We used a validated measure of clinical effect, "adequate relief," accepted as a primary endpoint and recommended for use in IBS trials.…”

“…Therefore, this study is not directly comparable to the current study. To our knowledge, no other studies report on the effect of eradication of D. fragilis in IBS patients, but clinical improvement of gastrointestinal symptoms other than IBS linked to eradication of D. fragilis have been described 24,31,44,45,47,[53][54][55][56][57][58][59][60] suggesting that at least in some individuals D. fragilis is pathogenic. Only two epidemiologic studies deal with the association between D. fragilis and IBS.…”

Dientamoeba fragilis, the Neglected Trichomonad of the Human Bowel

“…Ornidazole, another newer 5-nitroimidazole, was used in a randomized double-blind study comparing the efficacies of metronidazole and ornidazole in 112 patients with D. fragilis infection (194). Ornidazole outperformed metronidazole by achieving both clinical cure (96.4%) and parasite eradication (92.9%).…”

General Features of Patients Infected with Dientamoeba fragilis: Assessment of a Cohort of One Hundred Patients from Manisa Province

“…Bunun başlıca nedeni, D. fragilis'in uzun yıllar patojen olmayan bir intestinal protozoon olarak görülmesi yanında insanlara geçiş yolu gibi bazı özelliklerinin aydın-latılamaması ve uygun bir hayvan modeli oluşturula-mamasıdır [1][2][3][4][5] . Günümüzde D. fragilis özellikle çocuk hastalar için ciddi bir enfeksiyon etkeni olarak görülmekte, tanı konulan her hastanın uygun antimikrobiyal ajanlarla etkin bir tedavi alması önerilmektedir 1,3,8,9 . Çeşitli çalışmalarda D. fragilis'in sıklıkla 20 yaş altı kızlarda görüldüğü ve en sık ilkbahar ve yaz aylarında enfeksiyona rastlandığı bildirilmektedir 17,18 .…”

“…Son yıllarda dışkıdan DNA izolasyonu sonrası PZR testiyle enfeksiyonun tespit edilmesi yaygınlaşmaktadır 6,7 . Tedavide 5-nitroimidazoller ve paromomisinin etkili olduğu bildirilmektedir 2,3,8,9 . Dünyanın farklı bölgelerinde yapılan çok sayıda çalış-mada bağırsak parazitlerinin neden olduğu enfeksiyonlar ile toplumdaki eğitimsel ve sosyoekonomik düzeyin dü-şüklüğü, evlerde kanalizasyon sisteminin olmayışı ve genel hijyen yetersizliği arasında güçlü bir ilişki bulunduğu gös-terilmiştir [10][11][12][13][14][15][16] .…”