Relationship Between Nasal Cavity Microbial Colonization and Atopic Dermatitis Severity: A Systematic Review and Meta-analysis

Context: Atopic dermatitis is among the most common chronic diseases in children, with increasing prevalence. Objectives: This study evaluated the relationship between the microbial composition of nasal nares and atopic dermatitis severity. Study Selection: This meta-analysis included all types of studies (experimental and observational) on nasal colonization of pediatrics (age ≤ 19 years old) with a diagnosis of AD confirmed by a physician. The following search strategy was used in the databases: Atopic dermatitis AND (nasal OR nares). Results: Twenty-two studies were included in our analysis. Nine studies compared the odds of Staphylococcus aureus nasal colonization between AD pediatrics and non-AD healthy controls. In 13 studies, there was no control group. Subgroup analysis was performed on eight studies regarding AD severity in pediatrics with positive nasal colonization of S. aureus. Pooled analysis showed that S. aureus was colonized in 38% of the pediatrics with mild AD, 50% with moderate AD, and 22% with severe AD. The random-effects model showed that the odds of nasal colonization of S. aureus were significantly higher in AD pediatrics than in non-AD healthy controls (OR: 2.52; 95% CI (1.60, 3.97); I2 = 72%). Conclusions: The nasal cavity of pediatric AD patients was more colonized with S. aureus than in healthy children. More studies on children with severe AD are needed to accurately prove the role of S. aureus colonization in the severity of atopic dermatitis.