Clinical efficacy of Saccharomyces boulardii or metronidazole in symptomatic children with Blastocystis hominis infection

Abstract

Although many Blastocystis infections remain asymptomatic, recent data suggest it also causes frequent symptoms. Therapy should be limited to patients with persistent symptoms and a complete workup for alternative etiologies. The goal of this study was to compare the natural evolution (no treatment) to the efficacy of Saccharomyces boulardii (S. boulardii) or metronidazole for the duration of diarrhea and the duration of colonization in children with gastrointestinal symptoms and positive stool examination for Blastocystis hominis. This randomized single-blinded clinical trial included children presenting with gastrointestinal symptoms (abdominal pain, diarrhea, nausea-vomiting, flatulence) more than 2 weeks and confirmed B. hominis by stool examination (B. hominis cysts in the stool with microscopic examination of the fresh stool). The primary end points were clinical evaluation and result of microscopic stool examination at day 15. Secondary end points were the same end points at day 30. Randomization was performed by alternating inclusion: group A, S. boulardii (250 mg twice a day, Reflor®) during 10 days; group B, metronidazole (30 mg/kg twice daily) for 10 days; group C, no treatment. At day 15 and 30 after inclusion, the patients were re-evaluated, and stool samples were examined microscopically. On day 15, children that were still symptomatic and/or were still B. hominis-infected in group C were treated with metronidazole for 10 days. There was no statistically significant difference between the three study groups for age, gender, and the presence of diarrhea and abdominal pain. On day 15, clinical cure was observed in 77.7% in group A (n, 18); in 66.6% in group B (n, 15); and 40% in group C (n:15) (p < 0.031, between groups A and C). Disappearance of the cysts from the stools on day 15 was 80% in group B, 72.2% in group A, and 26.6% in group C (p = 0.011, between group B and group C; p = 0.013, between group A and group C). At the end of the first month after inclusion, clinical cure rate was 94.4% in group A and 73.3% in group B (p = 0.11). Parasitological cure rate for B. hominis was very comparable between both groups (94.4% vs. 93.3%, p = 0.43). Metronidazole or S. boulardii has potential beneficial effects in B. hominis infection (symptoms, presence of parasites). These findings challenge the actual guidelines.

Blastocystis hominis, un gran desconocido

“…La descripción de fallos terapéuticos y de intolerancia a dosis elevadas de metronidazol ha motivado el empleo de otros fármacos como cotrimoxazol o paromomicina 22 . Algunos autores han encontrado útiles probióticos como el Saccharomyces boulardii 21 .…”

Efficacy and Safety of Saccharomyces boulardii for Acute Diarrhea

“…After reading titles/abstracts, 36 potentially relevant studies were identified. Fourteen studies were excluded after full-text assessment for the following reasons: 3 studies evaluated the preventive effect of probiotic on diarrhea, [25][26][27] 3 studies had no control group, 28-30 2 were evaluated in patients who had persistent diarrhea, 31,32 2 were secondary publication of a study done by Cetina-Sauri et al, 33,34 1 included patients who had Blastocystis hominis infection without diarrhea, 35 1 used a mixed probiotic preparation for intervention, 36 data from 1 study were not reported, 15 and full-text of 1 study was not available. 20 Characteristics of excluded studies are presented in Supplemental Table 2.…”

In vitro sensitivity of Blastocystis hominis to garlic, ginger, white cumin, and black pepper used in diet

“…have been previously used for the treatment of diarrhea and enteritis associated with B. hominis as the sole identified pathogen in children and adults (Dunn and Boreham 1991). In a randomized, single blind study, Dinleyici et al (2010) compared no treatment to the efficacy of Saccharomyces boulardii or metronidazole (MTZ) for the duration of diarrhea and the duration of colonization in children with gastrointestinal symptoms and positive stool examination for B. hominis. On day 15, clinical cure was observed in 77.7% in group A (n=18); in 66.6% in group B (n=15); and 40% in group C (n=15) (p<0.031, between groups A and C).…”