# Changing Staphylococcus aureus Resistance in Atopic Dermatitis: Implications for Topical Antimicrobial Use From a Regional Study in the United Kingdom

## TL;DR

This study examines how Staphylococcus aureus resistance is changing in atopic dermatitis patients in the UK, highlighting concerns about topical antibiotic use.

## Contribution

The study provides new regional insights into S. aureus resistance patterns, particularly fusidic acid resistance in children.

## Key findings

- MRSA prevalence was 7% in community isolates and 11% in hospital isolates.
- Fusidic acid resistance was significantly higher in children compared to adults.
- Adults showed greater resistance to erythromycin, clindamycin, and tetracycline.

## Abstract

Background: Staphylococcus aureus plays a central role in the pathogenesis and exacerbation of atopic dermatitis, with superinfection contributing to disease severity and treatment challenges. As antimicrobial resistance evolves, understanding local susceptibility patterns is essential for dermatological practice and antibiotic stewardship.

Methods: A retrospective analysis was conducted of Staphylococcus aureus (S. aureus) isolates from skin and soft tissue infections in the Black Country region of the United Kingdom between 2019-2024, with community isolates obtained from general practice and hospital isolates from both inpatient and outpatient settings. Antimicrobial susceptibility was compared between adults and children (0-17 years), with methicillin-resistant S. aureus (MRSA) defined by flucloxacillin/oxacillin resistance. Statistical comparisons were made using Chi-squared testing.

Results: Among 30,160 community isolates, MRSA prevalence was 7%. Hospital-based S. aureus isolates (n=2,733) demonstrated 11% MRSA prevalence. Paediatric isolates (n=272) showed 10% MRSA prevalence, which were not significantly different from adults (p=0.47). Fusidic acid resistance, a key concern in dermatology due to its frequent topical use for atopic dermatitis, was significantly higher in children (21% vs 14%, p=0.002). Adults demonstrated greater resistance to erythromycin, clindamycin, and tetracycline.

Conclusion: This study highlights changing staphylococcal epidemiology with concerningly high MRSA and fusidic acid resistance in dermatological isolates. Given the frequent use of topical fusidic acid in atopic dermatitis, its role in management should be reconsidered. The findings underscore the need for dermatology-led antimicrobial stewardship to mitigate escalating community resistance in S. aureus infections.