CLINICAL AND MICROBIOLOGICAL CHARACTERISTICS OF PATIENTS WITH DEMODICOSIS AND CONCOMITANT ROSACEA
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Abstract
Relevance. Demodicosis, especially in combination with rosacea, represents a significant clinical problem because of the intensification of inflammatory manifestations, pronounced erythema, papulopustular elements and resistance to therapy. Modern studies show that an increased density of Demodex spp. and pronounced skin dysbiosis intensify immune-inflammatory reactions and aggravate the course of the disease. Despite the high prevalence and the growing number of observations, the comprehensive clinical and microbiological features of such patients have been insufficiently studied, which determines the need for further research to optimise diagnosis and the choice of effective therapeutic approaches. Aim of the study. To carry out a comprehensive clinical and microbiological characterisation of patients with demodicosis of the facial skin and concomitant rosacea in order to identify the factors that determine the severity of clinical manifestations and the features of microbial dysbiosis. Materials and methods. A cross-sectional comparative study of the «case–control» type was carried out, including 86 patients: the main group — 46 patients with demodicosis in combination with clinically confirmed rosacea, and the control group — 40 patients with isolated demodicosis. The severity of erythema (IGA Rosacea Severity Score), of inflammatory elements (IGA) and of subjective symptoms (VAS), the density of Demodex invasion (SSSB, individuals/cm²), the frequency of isolation and the microbial load of the main microorganisms (Staphylococcus epidermidis, Cutibacterium acnes, Bacillus spp., gram-negative bacteria), as well as polymicrobial colonisation, were assessed. Statistical analysis included Student's t-test, the χ² test and Pearson correlation analysis (p < 0.05). Results. Patients of the main group showed more pronounced erythema (3.1 ± 0.6 versus 1.8 ± 0.5 points; p < 0.001), a greater density of Demodex invasion (13.2 ± 3.4 versus 8.1 ± 2.7 individuals/cm²; p < 0.001) and more intense subjective symptoms. The frequency of detection of S. epidermidis, C. acnes, Bacillus spp. and gram-negative bacteria, as well as their microbial load and polymicrobial colonisation, were significantly higher when demodicosis was combined with rosacea. Significant correlations were established between the density of Demodex and the severity of erythema, papulopustular elements and burning, as well as with colonisation by S. epidermidis and C. acnes and with polymicrobial colonisation. Conclusion. The combination of demodicosis with rosacea is accompanied by a more severe clinical course and pronounced skin dysbiosis caused by the synergistic influence of a high load of Demodex spp. and opportunistic microbiota. The data obtained substantiate the need for a multimodal therapeutic approach that takes into account the parasitic, microbial and immune-inflammatory components of pathogenesis.
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