Skin microbiome in autoimmune pemphigus: a comparative analysis of bacterial diversity in relation to treatment

Teplyuk N.P., Kolesova Yu.V., Vartanova N.O., Leonova A.Yu., Toshchakov S.V., Kozlova A.D., Lepekhova A.A.

I.M. Sechenov First Moscow State Medical University, Russia
I.I. Mechnikov Research Institute of Vaccines and Sera, Moscow, Russia
National Research Center «Kurchatov Institute», Moscow, Russia

Background. Autoimmune pemphigus (AP) is a chronic, life-threatening disease of the skin and mucous membranes. Effective therapeutic options are currently available, but mortality in AP patients is higher than in the general population. The leading causes of death are infectious complications. Recent years have revealed the key role of microbiome alteration in a number of skin diseases. There is an increasing number of published studies examining the skin microbiome in patients with AP, but they have a number of limitations and require further research to understand the role of skin microbial composition in the course of AP.
Aims: to study the composition of skin microbiome by culture method in patients with AP (in active stage and in remission), to perform correlation analysis of microbiome composition and therapy received.
Materials and methods. Experimental prospective comparative study. Forty-four patients with diagnosed AP (16 men, 36.4%; 28 women, 63.6%; mean age 51.5±13.1 years) and 10 controls (7 women, 70%; 3 men, 30%; mean age 40±12.5 years) were included. Patients were enrolled between November 2021 and June 2023 at the V.A. Rakhmanov Clinic of Skin and Venereal Diseases.
Results. Seventy-nine skin samples were obtained and analysed. Only bacterial growth was detected in all submitted samples. No statistically significant difference was found between the composition of the microbiome of the unchanged skin of patients with AP in the active stage and in remission and the control group. In patients in the active stage of AP, a significant difference was found between the composition of the microbiome from rash elements and unchanged skin. S. aureus prevails on the skin from rash elements, and S. hominis dominates on unchanged skin. In patients before the start of glucocortlcosteroid (GCS) therapy, a predominance of S. aureus in the samples and a decrease in microbial diversity is noted. In patients receiving GCS therapy, S. hominis and S. epidermidis predominate, and greater microbial diversity is also noted.
Conclusions. The study revealed that the skin microbiome from the rash elements of patients with AP undergoes significant changes during the active stage of the disease, mainly due to colonisation of the skin by S. aureus. However, against the background of therapy with systemic GCS there is a tendency to normalisation of skin microflora composition, which demonstrates that there are no differences in the composition of the microbiome of patients in remission of AP and control groups.