{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T11:02:39Z","timestamp":1788433359165,"version":"build-2803163510"},"reference-count":54,"publisher":"Oxford University Press (OUP)","issue":"1","license":[{"start":{"date-parts":[[2021,8,5]],"date-time":"2021-08-05T00:00:00Z","timestamp":1628121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,1,17]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Rationale for review<\/jats:title>\n                  <jats:p>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.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>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 \u2018Giardia\u2019 AND \u2018treatment failure\u2019 OR \u2018refractory giardia\u2019 OR \u2018resistant giardia\u2019 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.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Key findings<\/jats:title>\n                  <jats:p>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.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>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.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/jtm\/taab120","type":"journal-article","created":{"date-parts":[[2021,8,4]],"date-time":"2021-08-04T11:16:41Z","timestamp":1628075801000},"source":"Crossref","is-referenced-by-count":33,"title":["Treatment strategies for nitroimidazole-refractory giardiasis: a systematic review"],"prefix":"10.1093","volume":"29","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0846-6422","authenticated-orcid":false,"given":"Daniel 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