Is it Effective to Treat Patients With Blastocystis Hominis Infection?

Study Overview
=================
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.

Official Title
-----------------
Is it Effective to Treat Patients With Blastocystis Hominis Infection? A Double-blind Placebo Controlled Randomized Trial

Conditions
-----------------
Blastocystis Hominis Infections

Intervention / Treatment
-----------------
* Drug: Metronidazole
* Drug: Placebo


Participation Criteria
=================
Eligibility Criteria
-----------------
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

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Metronidazole<br>Metronidazole 3x500 mg per day for 10 days | Drug: Metronidazole<br>* 3x500 mg/day for 10 days<br>|
| Placebo Comparator: Placebo<br>Placebo 3x1 tablet per day for 10 days | Drug: Placebo<br>* 3x1 tablet per day for 10 days<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Improvement of gastro-intestinal symptoms | 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 | 10-14 days after treatment with Metronidazol | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Blastocystis hominis, Metronidazole