Exacerbated symptoms in Blastocystis sp.-infected patients treated with metronidazole: two case studies
Blastocystis sp. is a gastrointestinal (GI) protozoan parasite reported to cause non-specific GI symptoms including diarrhea, flatulence, abdominal pain, and nausea. Complete eradication of Blastocystis sp. is rather challenging even with the drug of choice, i.e., metronidazole. Here, we report on two Blastocystis sp.-infected individuals, who presented increased parasite load and exacerbated symptoms upon treatment with the usual recommended dosage and regime of metronidazole. The two studies uniquely demonstrate for the first time a cyst count as high as fivefold more than the original cyst count before treatment and show an exacerbation of GI symptoms despite treatment. The study provides additional support in recognizing metronidazole resistance in Blastocystis sp. and its consequences towards the pathogenicity of the parasite.
KeywordsBlastocystis sp. Metronidazole Cysts Exacerbation of symptoms Subtypes
The authors would like to thank the staffs of Dr. Madhav Kudva’s Clinic, Pantai Medical Centre, and the staffs from Department of Parasitology, Faculty of Medicine, University Malaya.
This work was entirely supported by Fundamental Research Grant Scheme (FRGS), FP015-2017A, and Postgraduate Research Grant (PPP), PG140-2016A.
Compliance with ethical standards
This study was approved by the Medical Ethics Committee, University Malaya Medical Centre.
The authors declare that they have no conflict of interest.
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