Mårtensson et al. found no significant changes in SNOT-22 scores, microbiome, or levels of inflammatory markers (IL-6, IL-8, TNF-, IL-8, and MPO) in nasal lavage of CRSsNP patients following the administration of a nasal spray containing 13 lactic acid bacteria (Lactobacillus and Bifidobacterium) [40]. This evidence concerns the gene MPO and chronic rhinosinusitis without nasal polyps.