Treatment strategies for nitroimidazole-refractory giardiasis: a systematic review.

Abstract

RATIONALE FOR REVIEW:

Giardiasis is one of the most common human protozoal infections worldwide. First-line therapy of giardiasis includes nitroimidazole antibiotics. However, treatment failure with nitroimidazoles is increasingly reported, with up to 45% of patients not responding to initial treatment. There is no clear consensus on the approach to the management of nitroimidazole-refractory giardiasis. This systematic review aims to summarize the literature on pharmacotherapy for nitroimidazole-refractory giardiasis.

METHODS:

We conducted a systematic review of the literature to determine the optimal management strategies for nitroimidazole-refractory giardiasis. We searched Pubmed/MEDLINE, Embase and Cochrane library using the following search terms 'Giardia' AND 'treatment failure' OR 'refractory giardia' OR 'resistant giardia' with date limits of 1 January 1970 to 30 June 2021. We included all reports on humans, which described clinical outcomes of individuals with treatment refractory giardiasis, including case series and case reports. A descriptive synthesis of the data was conducted with pooling of data for interventions.

KEY FINDINGS:

Included in this review were five prospective studies, three retrospective studies, seven case series and nine case reports. Across these reports, a wide heterogeneity of treatment regimens was employed, including retreatment with an alternative nitroimidazole, combination therapy with a nitroimidazole and another agent and monotherapy with non-nitroimidazole regimens, including quinacrine, paromomycin and nitazoxanide. Retreatment with a nitroimidazole was not an effective therapy for refractory giardiasis. However, treatment with a nitroimidazole in combination with albendazole had a cure rate of 66.9%. In the included studies, quinacrine monotherapy was administered to a total of 179 patients, with a clinical cure rate of 88.8%. Overall, quinacrine was fairly well tolerated.

CONCLUSIONS:

Reports on the treatment of nitroimidazole-refractory giardiasis demonstrate a heterogeneous approach to treatment. Of these, quinacrine appeared to be highly effective, though more data on its safety are needed.

• Authors: Daniel L Bourque, Andreas Neumayr, Michael Libman, Lin H Chen
• Journal: Journal of travel medicine (J Travel Med) Vol. 29 Issue 1 (Jan 17 2022) ISSN: 1708-8305 [Electronic] England
• PMID: 34350966 (Publication Type: Journal Article, Systematic Review)
• Copyright: © The Author(s) 2021. Published by Oxford University Press on behalf of International Society of Travel Medicine. All rights reserved. For permissions, please e-mail: [email protected].

Chemical References

• Antiprotozoal Agents
• Nitroimidazoles
• Metronidazole
• Quinacrine

Topics

• Antiprotozoal Agents (therapeutic use)
• Giardia lamblia
• Giardiasis (drug therapy)
• Humans
• Metronidazole (therapeutic use)
• Nitroimidazoles (therapeutic use)
• Prospective Studies
• Quinacrine (adverse effects, therapeutic use)
• Retrospective Studies