Antiamoebic drugs for treating amoebic colitis

Department of Pediatrics, College of Medicine-Philippine General Hospital, University of the Philippines, Taft Avenue, Manila, National Capital Region, Philippines, 1000.
Cochrane database of systematic reviews (Online) (Impact Factor: 6.03). 02/2009; DOI: 10.1002/14651858.CD006085.pub2
Source: PubMed


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.

1 Follower
209 Reads
  • Source
    • "MTZ is currently the drug of choice for treating invasive amoebiasis, but it may not be sufficient to eliminate parasite cysts in the intestine. Moreover, some unpleasant adverse effects associated with metronidazole in some patients, and the possibility of parasite resistance to metronidazole has to be considered [95]. Treatment of patients with Clostridium difficile infection with MTZ generally reduces morbidity and mortality, although the number of patients that do not respond is increasing [96– 98]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Nitroheterocyclic compounds are widely used as therapeutic agents against a variety of protozoan and bacterial infections. However, the literature on these compounds, suspected of being carcinogens, is widely controversial. In this study, cytotoxic and genotoxic potential of three drugs, Nifurtimox (NFX), Benznidazole (BNZ), and Metronidazole (MTZ) was re-evaluated by different assays. Only NFX reduces survival rate in actively proliferating cells. The compounds are more active for base-pair substitution than frameshift induction in Salmonella; NFX and BNZ are more mutagenic than MTZ; they are widely dependent from nitroreduction whereas microsomal fraction S9 weakly affects the mutagenic potential. Comet assay detects BNZ- and NFX-induced DNA damage at doses in the range of therapeutically treated patient plasma concentration; BNZ seems to mainly act through ROS generation whereas a dose-dependent mechanism of DNA damaging is suggested for NFX. The lack of effects on mammalian cells for MTZ is confirmed also in MN assay whereas MN induction is observed for NFX and BNZ. The effects of MTZ, that shows comparatively low reduction potential, seem to be strictly dependent on anaerobic/hypoxic conditions. Both NFX and BNZ may not only lead to cellular damage of the infective agent but also interact with the DNA of mammalian cells.
    Journal of Parasitology Research 10/2009; 2009:463575. DOI:10.1155/2009/463575
  • Source
  • [Show abstract] [Hide abstract]
    ABSTRACT: The gastrointestinal mucosa is a target of many sexually transmitted infections, and major advances have increased our understanding of the consequences of such infections within the gastrointestinal system. HIV-1 is associated with a marked loss of mucosal CD4(+) T cells that express CC-chemokine receptor 5. This process seems to be more rapid and more severe in mucosa-associated lymphoid tissue than in the peripheral blood. Mechanistic insights into the underlying cause of acute and chronic gastrointestinal damage with HIV infection-microbial translocation, defects in intestinal epithelial barrier function and activation of a systemic immune response-have also been achieved. Increased understanding of the pathogenesis of mucosal HIV-1 infection may identify therapeutic targets to restore immunological function and the integrity of the intestinal mucosal epithelial barrier. The increasing prevalence of lymphogranuloma venereum in Europe, mostly in HIV-positive men who have sex with men, suggests a change in the epidemiology of what was previously considered to be a 'tropical' disease. The increasing incidence of acute HCV infection transmitted via sexual contact has also been fueled by high-risk sexual behaviors among men who have sex with men, many of whom are also HIV-positive. The first part of this Review discusses the pathogenesis and gastrointestinal complications of HIV infection, and the second part summarizes advances in our understanding of other sexually transmitted infections of the gastrointestinal system.
    Nature Reviews Gastroenterology &#38 Hepatology 09/2009; 6(10):592-607. DOI:10.1038/nrgastro.2009.143 · 12.61 Impact Factor
Show more

Preview (2 Sources)

209 Reads

We use cookies to give you the best possible experience on ResearchGate. Read our cookies policy to learn more.