Abstract: 【Abstract】    Objective    To investigate differences in the bacterial community composition and metabolic pathways of axillary skin between patients with axillary osmidrosis and healthy individuals, and to preliminarily explore the association between the axillary skin microbiota and the development of axillary osmidrosis.  Methods    Axillary skin bacterial samples were collected from 32 patients diagnosed with axillary osmidrosis at the Department of Dermatology, Kunming Yan’an Hospital, between October 2021 and October 2022, and from 16 healthy volunteers during the same period. High-throughput sequencing was performed to analyze the bacterial composition of the samples. Rarefaction curve analysis, Venn diagram analysis, community composition analysis, and beta diversity analysis were conducted. The metabolic functions of the microbiota were analyzed using the Kyoto Encyclopedia of Genes and Genomes （KEGG） database. Results    The axillary osmidrosis group had 7,837 unique operational taxonomic units （OTUs）, whereas the healthy control group had 1,922 unique OTUs, with 984 OTUs shared between the two groups. The total number of OTUs was substantially higher in the axillary osmidrosis group than in the healthy control group. Beta diversity analysis showed that the microbial community structure was more dispersed in the axillary osmidrosis group and more clustered in the healthy control group, with a statistically significant difference in community structure between the two groups （P < 0.001）. The four genera with the highest mean relative abundances in the axillary osmidrosis group were Staphylococcus （52.22%）, Corynebacterium （13.67%）, Rhodococcus （7.10%）, and Anaerococcus （6.59%）. In the healthy control group, the four most abundant genera were Corynebacterium （65.25%）, Anaerococcus （11.76%）, Staphylococcus （7.37%）, and Rhodococcus （5.41%）. At KEGG level 1, the axillary osmidrosis group showed significantly higher gene abundances in the categories of human diseases, metabolism, and organismal systems than the healthy control group. At KEGG level 2, female patients with axillary osmidrosis had higher gene abundances in the carbohydrate metabolism, amino acid metabolism, energy metabolism, and lipid metabolism pathways than male patients with axillary osmidrosis.  Conclusion    The composition of the axillary skin bacterial community differs to some extent between male and female patients with axillary osmidrosis and healthy individuals. Differences in metabolic pathway enrichment may be strongly associated with the production of the characteristic pungent odor of axillary osmidrosis.

Key words: Bromidrosis, Staphylococcus, RNA, ribosomal, 16S, Genetic testing, β-diversity, Pathways