In pediatric patients with atopic dermatitis (AD), both the nasal and skin microbiomes are associated with disease severity, according to study results published in the British Journal of Dermatology.
In a cross-sectional study conducted in The Netherlands, investigators sought to characterize the nasal and skin microbiome in children with AD relative to AD severity. They also examined the differences and associations between the nasal and skin communities in these individuals. The microbial composition of 90 nasal and 108 lesional skin samples from pediatric patients with AD was described via 16S ribosomal rRNA (16S rRNA) sequencing. Additional quantitative polymerase chain reaction (qPCR) for Staphylococcus aureus and S epidermidis was performed on the skin samples. Severity of AD was determined with use of the self-administered Eczema Area and Severity Index.
An association between the microbial composition of the samples and the severity of AD was observed in both the nose and skin samples (R2 =2.6%; P =.017 and R2 =7.0%; P =.005, respectively), with staphylococci reported to be the strongest drivers of the relationship. Other bacterial species also contributed, including Moraxella of the nose.
Overall, skin lesions were positive for S aureus in approximately 50% of the pediatric patients. Moreover, the presence and load of S aureus were not associated with the severity of AD. Despite the fact that the nose and skin harbor distinct microbial communities (n=48 paired samples; P <.001), study findings demonstrated that links do exist between species in the nose and other species on the skin.
The investigators concluded that although both the nasal and skin microbiome are related to the severity of AD in children, the skin microbiome is responsible for more of the variation in disease severity. Additional studies are warranted to explore the role played by microbial species in AD, their interaction with the host and other species, and the interactions between different microbial communities of the body. Future studies need to utilize uncontrolled longitudinal cohorts, along with adequate sequencing and culture-based techniques.
Totté JEE, Pardo LM, Fieten KB, et al. The nasal and skin microbiome are associated with disease severity in pediatric atopic dermatitis [published online February 9, 2019]. Br J Dermatol. doi:10.1111/bjd.17755