1114 Which Clinical Features Are Useful in Predicting Presence of Staphylococcus Aureus colonization/Infection in Childhood Atopic Dermatitis?

Wednesday, 14 October 2015
Hall D1 Foyer (Floor 3) (Coex Convention Center)

Kam Lun E. Hon, MD , Paediatrics, Prince of Wales Hospital, Hong Kong, Hong Kong

Yin Ching K. Tsang , Paediatrics, The Chinese Unbiversity of Hong Kong, Hong Kong, Hong Kong

Ting Fan Leung, MD, FRCPCH, FAAAAI , Department of Paediatrics, Prince of Wales Hospital, Hong Kong, Hong Kong

Introduction: Staphylococcus aureus (SA) colonization/infection is important in the pathophysiology of childhood atopic dermatitis (AD). This study evaluated which clinical features may predict presence of SA colonization/infection, and reviewed antimicrobial sensitivity of SA in patients with AD.

Methods: The associations between bacteriologic culture results of skin swabs (taken at the most severely affected area and at the antecubital fossa) and SCORing-Atopic-Dermatitis (SCORAD), skin hydration, transepidermal water loss (TEWL) and quality of life were evaluated.

Results: Moderate-to-heavy growth of SA was present in 31% of the swabs of the most severe area and in 16% of the flexural (antecubital fossae) areas of 95 AD patients (12.5±4.8 years). Binomial logistic regression showed moderate-to-heavy growth of SA were associated with objective SCORAD (p=0.004) and lesion intensity [erythema (p=0.022) and lichenification (p=0.035)] in the severe area; and excoriation (p=0.024) and TEWL (p=0.009) in the antecubital fossa. The relative risk of isolating moderate-to-heavy growth of SA in the most affected area in patients with severe disease (Objective SCORAD >40) is 2.73 (1.43 – 5.21, p =0.001). Any growth of SA in either swab sites was associated with objective SCORAD and lesion intensity (p=0.001-0.019). SA had no association with quality of life and other clinical parameters. All specimens of methicillin-sensitive SA were sensitive to cloxacillin. All methicillin-resistant SA (5.7%) was sensitive to cotrimoxazole and fusidic acid.

Conclusions: Clinical features, especially severity and lesion intensity, are useful in “predicting” presence of SA colonization/infection in AD patients. Cloxacillin has a favourable sensitivity profile for methicillin-sensitive-SA, and cotrimoxazole and fusidic acid for methicillin-resistant-SA. These findings will facilitate management of patients before bacteriology results become available.