Methods: Twenty-eight patients with atopic dermatitis and 8 healthy control subjects were enrolled. Urine was obtained in all subjects and serum was obtained in eighteen atopic dermatitis patients. After genomic DNA was extracted from the urine and serum, 16s ribosomal DNA was amplified using the universal primer, sequenced through the next generation sequencer, and then the sequenced data was analyzed using bioinformatics.
Results: The bacterial composition was nearly identical between serum and urine. However, there was notable difference of bacterial composition in the urine of the normal control and the atopic dermatitis patients. In the control group, proportion of Lactococcus, Leuconostoc, Lactobacillus, Lactobacillales(o) were significantly higher than in the patients group, and that of Alicyclobacillus, Propionibacterium, Streptophyta(o) were increased in the patients group than in the control group. Pseudomonas was commonly found in the both groups. Before treatment, Alicyclobacillus and Comamonadaceae were frequently found, however their proportion were decreased and Acinetobacter and Oxalobacteraceae(f) were increased after treatment in the urine of atopic dermatitis patients
Conclusions: We confirmed the systemic bacterial composition in the atopic dermatitis and normal controls through the metagenomic analysis of bacterial DNA in the urine and serum.