Antiamoebic drugs for treating amoebic colitis
Editorial Group: Cochrane Infectious Diseases Group
Published Online: 15 APR 2009
Assessed as up-to-date: 4 DEC 2008
Copyright © 2009 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
How to Cite
Gonzales MLM, Dans LF, Martinez EG. Antiamoebic drugs for treating amoebic colitis. Cochrane Database of Systematic Reviews 2009, Issue 2. Art. No.: CD006085. DOI: 10.1002/14651858.CD006085.pub2.
- Publication Status: New
- Published Online: 15 APR 2009
Entamoeba histolytica infection is common in developing countries, and up to 100,000 individuals with severe disease die every year. Adequate therapy for amoebic colitis is necessary to reduce the severity of illness, prevent development of complicated disease and extraintestinal spread, and decrease transmission.
To evaluate antiamoebic drugs for treating amoebic colitis.
In September 2008, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (2008, Issue 3), MEDLINE, EMBASE, LILACS, mRCT, and conference proceedings. We contacted individual researchers, organizations, and pharmaceutical companies, and checked reference lists.
Randomized controlled trials of antiamoebic drugs given alone or in combination, compared with placebo or another antiamoebic drug for treating adults and children diagnosed with amoebic colitis.
Data collection and analysis
Two authors independently assessed the eligibility and methodological quality of trials, and extracted and analysed the data. We calculated clinical and parasitological failure rates, relapse, and adverse events as risk ratios (RR) with 95% confidence intervals (CIs), using a random-effects model. We determined statistical heterogeneity and explored possible sources of heterogeneity using subgroup analyses. We carried out sensitivity analysis using trial quality to assess the robustness of the results.
Thirty-seven trials, enrolling 4487 participants, met the inclusion criteria. Only one trial used adequate methods for randomization and allocation concealment, was blinded, and analysed all randomized participants. Only one trial used a E. histolytica stool antigen test. Tinidazole reduced clinical failure compared with metronidazole (RR 0.28, 95% CI 0.15 to 0.51; 477 participants, eight trials) and was associated with fewer adverse events. Compared with metronidazole, combination therapy resulted in fewer parasitological failures (RR 0.36, 95% CI 0.15 to 0.86; 720 participants, 3 trials).
Tinidazole is more effective in reducing clinical failure compared with metronidazole and has fewer associated adverse events. Combination drug therapy is more effective in reducing parasitological failure compared with metronidazole alone. However, these results are based on trials with poor methodological quality so there is uncertainty in these conclusions. Further trials of the efficacy of antiamoebic drugs, with better methodological quality, are recommended. More accurate tests to detect E. histolytica are needed, particularly in countries where concomitant infection with other bacteria and parasites is common.
Plain language summary
Antiamoebic drugs for treating amoebic colitis
Amoebic colitis is caused by the parasite Entamoeba histolytica. This protozoan is distributed throughout the world and is commonly acquired by ingestion of contaminated food or water. It is estimated that about 40 to 50 million people infected with E. histolytica develop amoebic colitis or extraintestinal abscesses, which result in up to 100,000 deaths per year.
Metronidazole is currently the drug of choice for treating invasive amoebiasis in adults and children, but it may not be sufficient to eliminate parasite cysts in the intestine. Combinations with other drugs are therefore also used. However, the evidence to support combination therapy has not been reviewed. Also, some unpleasant adverse effects associated with metronidazole in some patients, and the possibility of parasite resistance to metronidazole has to be considered.
This review compares different drugs used against amoebic colitis, alone or in combination, and also assesses single-dose regimens versus longer regimens.
Thirty-seven trials with 4487 participants were included, and only one was of high methodological quality. Tinidazole reduced clinical failure compared with metronidazole and was associated with fewer adverse events. Combination therapy resulted in fewer parasitological failures than metronidazole alone.
The authors conclude that tinidazole appears more effective at reducing clinical failures than metronidazole, and has fewer associated adverse events. There is insufficient evidence to draw conclusions regarding the efficacy of the other antiamoebic drugs. However, the trials' methodological quality was generally inadequate. Also, the choice of antiamoebic drugs would depend largely on the availability and accessibility of drugs.
Better quality randomized trials with standardized outcomes are needed to evaluate the efficacy of drugs for treating amoebic colitis. There is also a need for improved, reliable diagnostic tests that can be used in developing countries.
2008年9月時我們搜尋Cochrane Infectious Diseases Group Specialized Register, CENTRAL (2008, Issue 3) 、MEDLINE、EMBASE、LILACS、mRCT,以及研討會手冊。此外還與本領域相關機構、藥廠及研究人員聯繫,並檢查參考資料清單。
由2名作者獨立評估試驗之適用性及方法學品質，並摘錄及分析數據。我們使用隨機效果模型，將臨床及寄生蟲學失敗率、復發、及不良作用計算為風險比(risk ratio；RR)與95%信賴區間(confidence intervals；CIs)。我們使用亞族群分析判定統計異質性並探詢可能之異質性來源。茲使用試驗品質進行敏感性分析以評估結果之可靠度。
共有招收4487名參與者之37項試驗符合收錄標準。其中僅有1項試驗使用了適當之方法進行隨機分派及分組隱匿，為遮盲試驗，並分析所有之隨機分派參與者。僅有1項試驗使用了溶組織內阿米巴(E. histolytica)糞便抗原試驗。Tinidazole相較於metronidazole可減少臨床失敗率(RR 0.28, 95% CI 0.15 to 0.51; 477名參與者，8項試驗)，且其具有較少之不良作用。相較於metronidazole，組合治療可產生較少之寄生蟲性失敗(RR 0.36, 95% CI 0.15 to 0.86; 720名參與者，3項試驗)。
此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。
阿米巴性結腸炎係由寄生蟲溶組織內阿米巴(Entamoeba histolytica)造成。此種原蟲分布於全世界，且其常係經由攝入污染之食物或水而感染。估計共有約四至五千萬名感染溶組織內阿米巴(E. histolytica)之患者會發生阿米巴性結腸炎或腸外膿瘍，其可造成每年高達100,000人死亡。Metronidazole目前係用以治療成人及兒童之侵襲性阿米巴痢疾首選藥物，但其可能並不足以清除腸中之寄生蟲性囊腫。因此亦使用與其他藥物之組合。然而，尚未針對可支持組合治療之證據進行回顧。同時，亦必須考量metronidazole 在部分病患體內所產生之不良作用以及寄生蟲可能對metronidazole 具有抗藥性。本回顧係比較用於對抗阿米巴性結腸炎之不同藥物(包括單獨或組合使用者)，並亦評估單劑療程對較長之療程。共收錄包括4487名參與者之37項試驗，而其中只有1項具有高方法學品質。Tinidazole 相較於metronidazole可更有效的減少臨床失敗，並具有較少之不良作用。相較於單獨使用之metronidazole，組合藥物治療可造成較少之寄生蟲性失敗。回顧作者歸結認為，tinidazole似乎可較metronidazole 更為有效的減少臨床失敗，並具有較少之不良作用。並無足夠之證據可取得關於其他抗阿米巴藥物功效之結論。然而，該等試驗一般皆不具有適當之方法學品質。同時，抗阿米巴藥物之選擇可能大量取決於藥物之可取得性。茲需要具有標準結果之較佳品質隨機試驗以評估藥物對於治療阿米巴性結腸炎之功效。亦需要可用於開發中國家之改良式可靠之診斷測試方法。