Evaluation of Helicobacter pylori and Small Intestinal Bacterial Overgrowth in Subjects With Rosacea

Systemic abnormalities in the immune system may contribute to rosacea pathogenesis. Several studies have found a higher prevalence of abnormal bacterial growth, such as Helicobacter pylori (H. pylori) and small intestinal bacterial overgrowth (SIBO) in rosacea subjects. However, discrepancies remain in the literature, likely perpetuated by inconsistent testing methods and incomplete controlling for potential confounders.

We aimed to evaluate the prevalence of H. pylori and SIBO in rosacea subjects after controlling for several potential confounders.

This cross-sectional study evaluated subjects with papulopustular or erythematotelangiectatic rosacea. Subjects with previous or existing gastrointestinal (GI) disease, GI surgery, autoimmune disorders, immunosuppression, or significant comorbidities were excluded. Certain medication use (antibiotics, steroids, GI-modulating medications, anti-inflammatories) required an appropriate washout period. Rosacea history and severity were assessed. Subjects answered questions regarding their rosacea and GI health. H. pylori andSIBO were evaluated by ¹³C-urea breath test and glucose-breath test methods, respectively.

Of 27 subjects, 14.8% (N=4) tested positive for H. pylori and 33.3% (N=9) tested positive for SIBO. Compared to the general population prevalence, the proportion of H. pylori in the rosacea cohort was significantly less (p=0.02). Though the estimated population prevalence of SIBO had a wider range, compared to midrange, the prevalence of SIBO in the rosacea cohort was greater (p<0.001). There were no significant associations between demographics, rosacea characteristics, or GI symptoms and H. pylori or SIBO positivity.  Conclusion: When eliminating several potential confounders, SIBO is more prevalent in subjects with rosacea compared to the general population. Thus, SIBO may be associated with rosacea, though it remains incompletely understood whether SIBO itself contributes to rosacea pathophysiology or rather SIBO prevalence and rosacea are both downstream effects of abnormalities in systemic immunity. Future studies are warranted to elucidate this relationship further, though this observed association may be promising for novel therapeutic targets in rosacea treatment.