Background: Bacterial infectious skin diseases are common dermatological conditions caused by various pathogenic bacteria. In recent years, their incidence has remained high due to factors such as climate change and the overuse of antibiotics, posing persistent challenges for clinical diagnosis and treatment. This study aimed to identify plasma proteins causally associated with cellulitis, erysipelas, cutaneous abscess, furuncle, and carbuncle through Mendelian randomization (MR) analysis. Methods: We analyzed genetic instruments of 4907 proteins derived from the Icelandic population together with genome-wide association study (GWAS) data from the FinnGen project to investigate circulating plasma proteins involved in bacterial infectious skin diseases. To validate causal associations, we employed Steiger filtering, reverse MR analysis, phenome-wide association studies (pheWAS), Bayesian colocalization, summary data–based Mendelian randomization (SMR) and (Heterogeneity in Dependent Instruments) HEIDI test. Furthermore, we conducted protein–protein interaction (PPI) network analysis and drug target evaluation to assess therapeutic potential. Results: We identified five key proteins associated with bacterial infectious skin diseases. Specifically, FN1 was associated with erysipelas; ULK3 and CSK were associated with cellulitis; and ARHGAP25 and ENTPD6 were associated with cutaneous abscess, furuncle, and carbuncle. Conclusion: Through a systematic proteome-wide Mendelian randomization analysis with multiple layers of validation, this study prioritised a set of host plasma proteins associated with different subtypes of bacterial infectious skin diseases, providing a reference for biomarker exploration, further elucidation of disease-related molecular mechanisms, and subsequent research into non-antibiotic intervention strategies. Keywords: proteome, mendelian randomization, bacterial infectious skin diseases, erysipelas, cellulitis, cutaneous abscess
Zheng et al. (Sun,) studied this question.