Emerging trends in human skin microbiota in diabetic and non-diabetic subjects

Introduction: The skin hosts a diverse microbiota, and its disruption can lead to pathogen colonisation. This study aimed to assess differences in skin microbiota between individuals with and without diabetes, and explore variations by sex, skin location and skin tone. Methods: A cross-sectional study of 100 participants with diverse skin tones (50 diabetic, 50 non-diabetic; 43 males, 57 females) analysed microbiota from the right plantar forefoot and interdigital spaces using next-generation sequencing. Results: Both groups shared similar bacterial microbiota, with Staphylococcus hominis and S. epidermidis being the most common. However, the fungal diversity differed between groups, and diabetic participants had higher abundances of Gram-negative pathogens, particularly Klebsiella aerogenes pneumoniae and a Pseudomonas sp., in the plantar region. The interdigital spaces of diabetics also showed an increase in a Pseudomonas sp., especially P. aeruginosa, while non-diabetics had more Gram-positive Streptococci. Various positive interactions between commensal and pathogenic microbes differed between groups. Conclusions: This study highlights microbiota variations associated with diabetes, skin location, and other factors. Whether these changes contribute to or result from diabetes remains unclear. Further research may enhance understanding of skin health and infection risks in diabetes. Level of clinical evidence: Prospective and retrospective cohort studies (n≥30 patients) = 2