Comparison of skin microbiome components analyzed by culture method in patients with autoimmune pemphigus

BACKGROUND: Autoimmune pemphigus is a group of severe, potentially fatal bullous dermatoses affecting both skin and mucous membranes. To date, the pathogenesis and therapeutic approaches to the disease have been well studied; despite this, secondary bacterial complications remain the leading cause of death in these patients. Study of qualitative and quantitative composition of skin microbiome in chronic dermatoses is an actual contemporary problem. These data allow one to investigate the influence of microorganisms on the disease severity, relapse rate and remission duration. Analysis of literature sources shows a high interest of scientific groups in the study of microbiome components of the skin and mucous membranes in patients with bullous dermatoses, however, similar works on autoimmune bullous vesicles are still limited.

AIM: to compare the composition of the skin microbiome in patients with autoimmune pemphigus and a healthy control group based on the results of the culture method performed.

MATERIALS AND METHODS: Experimental, prospective, comparative study. Seventeen patients with previously or first-time diagnosis of autoimmune vesicular disease, as well as a control group of 10 people were included in the study. Patients were enrolled between November 2021 and November 2022. Rakhmanov clinic. All study participants had their skin swabs taken (for patients with rash elements and with apparently unchanged skin in the back or chest area; for the control group, from healthy skin in the back area), after which the material was taken to the laboratory for culture study.

RESULTS: Data from 17 patients (5 men, 29.5%; and 12 women, 70.5%; average age 51±13.3 years) were analyzed. Also included were 10 individuals from the control group (7 women, 70%; and 3 men, 30%; mean age 40±14.7 years). Bacterial growth was detected in all samples submitted. No other microgranisms were identified. Eleven bacterial species were detected on the skin from the rash elements. The most frequent species encountered were: Staphylococcus aureus (in 70.59% of patients), Staphylococcus epidermidis (35.3%), Staphylococcus hominis (17.63%), Staphylococcus haemolyticus and Corynebacterium aurimucosum (11.8%). Twelve bacterial species were isolated on visibly unchanged skin. The most frequent were S. epidermidis (52.9%), S. aureus and S. hominis (35.3%), Staphylococcus capitis and Staphylococcus warneri (17.65%), Micrococcus luteus (11.76%). Fifteen bacterial species were identified in the control group. The following species were found most frequently: S. hominis (60%), S. capitis (50%), M. luteus (40%), S. epidermidis, S. haemolyticus and S. warneri (20%). The mean value of bacterial colony-forming units per 1 ml on rash elements was 5106.33±8752.46; on visibly unchanged skin 593.23±1223.06; in the control group 349.33±915.52.

CONCLUSIONS: We were able to obtain primary data on the composition of the skin microbiome in 17 patients with various types of autoimmune pemphigus and compare them with the control group. The data obtained demonstrate a great variety of microbial communities on the skin and a significant quantitative difference in the composition on the skin of patients and controls. A limitation of the study is the chosen cultural method, which cannot fully reflect all the diversity of microorganisms. To confirm the hypotheses put forward, we plan to conduct an additional study involving a larger number of patients and using genomic sequencing methods to identify microbial communities.