Is it Effective to Treat Patients With Blastocystis Hominis Infection?

Phase 4

• Conditions: Blastocystis Hominis Infections
• Interventions: Drug: Placebo; Drug: Metronidazole

• Registration Number: NCT01521403
• Lead Sponsor: University of Lausanne Hospitals

Brief Summary

The objective of this study is to determine whether in the setting of primary health care it is effective to treat with metronidazole returning travellers with gastrointestinal symptoms and B. hominis in the stool or not.

Detailed Description

Prevalence of B. hominis is between 30-50% in developing countries. Many travellers visit developing countries and are therefore at risk to be infected by this parasite. It's frequent that travellers return from developing countries with gastro-intestinal symptoms and approximately 10% of them have B. hominis as the sole parasite identified in the stools. Some anti-infective drugs, including metronidazole, trimethoprim-sulfamethoxazole and nitazoxanide, have shown to have activity against B. hominis, but there is still controversy about the pathogenic potential of B. hominis and there is no consensus about the indications for treatment.

It is hypothesised that metronidazole is more effective than placebo in returning travellers with gastrointestinal symptoms and B. hominis as the sole intestinal parasite identified in the stool.

Study Timeline

• Study First Submitted: 2012-01-25
• Study First Submitted QC: 2012-01-27
• Study First Posted: 2012-01-30
• Study Start: 2012-11
• Primary Completion: 2018-12-31
• Status Verified: 2022-08
• Last Update Submitted: 2022-08-22
• Last Update Posted: 2022-08-23
• Study Completion: 2022-12-30

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 200

Inclusion Criteria

• ≥ 18 years
• Gastrointestinal symptoms for more than 10 days
• B. hominis in any quantity in at least one stool specimen out of 3 examined
• No other pathogenic micro-organism identified

Exclusion Criteria

• Fever > 37.5°
• bloody diarrhoea
• weight loss > 10% of usual body weight
• significant decrease of general condition
• oncological diseases
• immune deficiencies
• known chronic intestinal diseases
• use of anti-protozoan drugs in the last 2 weeks
• use of anti-coagulant treatment or antabuse
• pregnant and lactating women

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	Placebo 3x1 tablet per day for 10 days
Metronidazole	Metronidazole	Metronidazole 3x500 mg per day for 10 days

Primary Outcome Measures

Name	Time	Method
Improvement of gastro-intestinal symptoms	10-14 days after treatment with Metronidazol	The improvement of the following symptoms will be evaluated: * Presence of unusually soft or unformed stools in the last 3 days (yes or no); * Average number of stools per day in the last 3 days; * Maximal abdominal pain in the last 3 days on a scale from 0-10; * Bloating in last 3 days on a scale from 0-10; * Flatulence in last 3 days on a scale from 0-10

Trial Locations

Locations (1)

Travel Clinic, Department of Ambulatory Care and Community Medicine, University Hospital of Lausanne, Switzerland; 🇨🇭 Lausanne, Vaud, Switzerland