Staphylococcus aureus skin colonization in atopic dermatitis patients.

Area of Science:

• Dermatology
• Microbiology
• Epidemiology

Background:

• Atopic dermatitis (AD) is a chronic inflammatory skin condition.
• Skin colonization by Staphylococcus aureus is common in AD patients.
• The extent and distribution of S. aureus colonization in AD require further investigation.

Purpose of the Study:

• To compare Staphylococcus aureus skin colonization levels in patients with atopic dermatitis (AD) versus healthy controls.
• To quantify S. aureus density on different types of AD skin lesions.
• To assess the antibiotic sensitivity of S. aureus strains isolated from AD patients.

Main Methods:

• Quantification of total aerobe and Staphylococcus aureus counts (CFU/cm2) on skin.
• Comparison of colonization between AD patients (n=21) and healthy controls (n=22).
• Isolation and antibiotic sensitivity testing of S. aureus strains from lesional skin.

Main Results:

• Significantly higher total aerobe counts, S. aureus fraction, and carrier frequency in AD patients' normal skin.
• S. aureus density was 100-1,000 times higher on dermatitic, lichenified, and impetiginized skin compared to normal AD skin.
• Antibiotic sensitivity of 190 S. aureus strains to 5 topical antibiotics was determined.

Conclusions:

• Atopic dermatitis patients exhibit markedly increased Staphylococcus aureus skin colonization.
• Severe S. aureus colonization on lesional skin poses biological and epidemiological risks.
• Findings support the need for preventive and therapeutic strategies targeting S. aureus in AD.