Norwegian National Advisory Unit on Tropical Infectious Diseases, Department of Medicine, Haukeland University Hospital.
Department of Clinical Science and Faculty of Medicine, University of Bergen, Bergen, Norway.
Curr Opin Infect Dis. 2020 Oct;33(5):355-364. doi: 10.1097/QCO.0000000000000668.
Giardiasis remains a common cause of diarrhea and intestinal enteropathy globally. Here we give an overview of clinical treatment studies and discuss potential mechanisms and molecular targets for in-vitro testing of drug resistance.
Giardia is a cause of disease both in diarrheal and nondiarrheal cases. The prevalence of treatment refractory giardiasis is increasing. Recent studies reveal 5-nitroimidazole refractory infection occurs in up to 50% of cases. Mechanisms of drug resistance are not known. Placebo controlled studies of drug efficacy, taking the self-limiting course of giardiasis into account, has not been reported. No randomized controlled trials of treatment of refractory infection have been performed the last 25 years. Based on the clinical studies reported, combination treatment with a 5-nitroimidazole and a benzimidazole is more effective than repeated courses of 5-nitroimidazole or monotherapies in refractory cases. Quinacrine is effective in refractory cases, but potentially severe side effects limit its use.
A combination of a 5-nitroimidazole and albendazole or mebendazole, and quinacrine monotherapy, are rational choices in nitroimidazole refractory infections, but randomized controlled studies are needed. Further research into more recent clinical isolates is necessary to uncover mechanisms for the increase in metronidazole refractory giardiasis observed during the last decade.
贾第虫病仍然是全球范围内导致腹泻和肠内肠病的常见原因。本文概述了临床治疗研究，并讨论了体外药物耐药性检测的潜在机制和分子靶点。
贾第虫是引起腹泻和非腹泻病例的病因。治疗难治性贾第虫病的患病率正在增加。最近的研究表明，多达 50%的病例存在 5-硝基咪唑耐药感染。耐药机制尚不清楚。考虑到贾第虫病的自限性病程，尚未报道关于药物疗效的安慰剂对照研究。过去 25 年，没有针对难治性感染的随机对照试验。根据已报道的临床研究，在难治性病例中，5-硝基咪唑和苯并咪唑的联合治疗比重复使用 5-硝基咪唑或单一疗法更有效。奎纳克林在难治性病例中有效，但潜在的严重副作用限制了其使用。
在 5-硝基咪唑耐药感染中，联合使用 5-硝基咪唑和阿苯达唑或甲苯达唑以及奎纳克林单药治疗是合理的选择，但需要进行随机对照研究。需要对最近的临床分离株进行进一步研究，以揭示过去十年中观察到的甲硝唑耐药性贾第虫病增加的机制。
