Background: Aging and oxidative stress seem to play a key role in the onset and
progression of ocular surface diseases. Dry Eye Syndrome (DES) is a multifactorial disease of the
tears and ocular surface in which symptoms may interfere with the ability to work and carry out
Methods: This clinical trial was a pilot study to evaluate the effects of supplementation with
mixture (Saccharomyces boulardii MUCL 53837 and Enterococcus faecium LMG S-28935) on the
tear film. Following the run-in period subjects were randomized in two groups: group A (n.30 subjects)
and group B (n.30 subjects). Group A (control) treated only with substitute tear and group B
treated with substitute tear + mixture (probiotic).
Results: The data obtained in the two study groups A and B were, respectively the following:
Schirmer I: 9.2±0.2 vs. 12.8±0.4 (p< 0.001); Schirmer II: 3.6±0.1 vs. 4.6±0.2 (p<0.001); BUT
3.8±0.3 vs. 6.2±0.2 (p<0.001).
Culture test showed initial bacterial growth in group “A” (placebo) 27 out of 60 samples tested,
corresponding to 45.0% and “B” after treatment (probiotic) was found positive culture whit growth
of bacteria in 18 tests equal to 30.0%.
The total numbers of isolations of aerobic and anaerobic bacteria found group A and B after treatment.
A reduction of 23 to 16 strains of aerobic and anaerobic isolates from 13 to 7 has been found.
Conclusion: The administration of probiotics strains was effective in reducing DES. In light of these
results, we have identified our probiotic (Saccharomyces boulardii MUCL 53837 and Enterococcus
faecium LMG S-28935) activity integration with the action of tear substitutes, along with
standardization of clinical parameters of the tear film and microbiological activity in restoring of the
microbiota ocular surface subject with DES.