Objective To investigate the relationships of the severity of rosacea with serum testosterone, estradiol and intestinal flora in rosacea patients.

Methods A total of 102 patients with rosacea diagnosed and treated in our hospital from March 2021 to September 2022 were selected as observation group, and 105 healthy volunteers were selected as control group. According to differed severity of clinical symptoms, the patients were divided into mild group (64 cases), moderate group (17 cases) and severe group (21 cases). Serum testosterone and estradiol levels were detected by radioimmunoassay; the copy numbers of Enterococcus, Escherichia coli, Lactobacillus and Bifidobacterium in intestinal flora were determined by fluorescent quantitative polymerase chain reaction; Pearson correlation analysis was conducted to analyze the correlations of serum testosterone, estradiol levels with intestinal flora in rosacea patients.

Results Compared with the control group (445.34±68.75) ng/L, (294.25±42.97) pmol/L, the serum testosterone level (547.06±75.13) ng/Lof rosacea patients in the observation group was obviously higher, and the estradiol level (225.28±25.89) pmol/L was obviously lower (P < 0.05). The serum estradiol level of males with rosacea in the observation group was obviously lower than that of males in the control group, and the serum testosterone level of females with rosacea in the observation group was obviously higher than that of females in the control group (P < 0.05). Compared with the control group, the number of intestinal Bifidobacteria and Lactobacilli in rosacea patients in the observation group decreased obviously, the number of Escherichia coli and Enterococcus increased obviously, and the B/E decreased (P < 0.05). Compared with mild group, serum testosterone level was increased and estradiol was decreased in moderate and severe groups, and the difference was statistically significant (P < 0.05). Serum testosterone level in the severe group was higher, and estradiol was lower than that in the moderate group, the differences were statistically significant (P < 0.05). Pearson analysis showed that the serum testosterone level in rosacea patients was negatively correlated with the number of Bifidobacteria and Lactobacillus (r=-0.409, -0.485, P < 0.05), and positively correlated with the number of Escherichia coli and Enterococcus (r=0.502, 0.431, P < 0.05); serum estradiol level was positively correlated with the number of Bifidobacteria and Lactobacillus (r=0.417, 0.526, P < 0.05), and negatively correlated with the numbers of Escherichia coli and Enterococcus (r=-0.481, -0.4, 21, P < 0.05).

Conclusion The increase of serum testosterone level and the decrease of estradiol level in rosette acne patients are related to the imbalance of intestinal flora, and play certain roles in the occurrence and development of rosette acne.