Pre- and post-induction probiotic administration in experimental otitis media with effusion: effects on effusion resolution and inflammation

Background Otitis media with effusion (OME) is a common inflammatory middle ear disease, and the efficacy of available medical treatments remains controversial. Probiotics have emerged as a potential non-antibiotic therapeutic strategy.Aims/Objectives To compare the efficacy of methylprednisolone, montelukast, and Lactobacillus reuteri (L. reuteri) in the treatment of experimentally induced OME model.Material and Methods Thirty-five male Wistar albino rats were randomly assigned to five groups (n = 7). OME was induced by intratympanic histamine injection. Groups comprised control, methylprednisolone, montelukast, post-induction probiotics, and pre- and post-induction probiotics. Effusion resolution was assessed otomicroscopically, and submucosal inflammatory leukocyte infiltration was evaluated histologically.Results Effusion resolution differed significantly among groups (p < 0.001), reaching 78.6% with methylprednisolone and 85.7% with pre- and post-induction probiotics, compared with 0% in controls. All treatment groups showed significantly lower submucosal inflammatory leukocyte counts than controls (p < 0.001). No statistically significant difference in inflammatory leukocyte counts was detected between the combined pre- and post-induction probiotic group and the methylprednisolone group in this exploratory study.Conclusions and Significance L. reuteri exhibited anti-inflammatory activity in this histamine-induced OME model. Combined pre- and post-induction probiotic administration was associated with greater effusion resolution than post-induction treatment alone, although longer total exposure may have contributed to this finding. These findings support further investigation of probiotics in OME but do not establish equivalent efficacy to methylprednisolone.