Superantigens of Staphylococcus Aureus Colonization in Atopic Dermatitis and Treatment Efficacy of Oral Cefuroxim in Vietnamese Patients

BACKGROUND: Atopic dermatitis (AD) is a common, chronic, relapsing, genetically determined inflammatory skin disorder. Staphylococcus aureus (S. aureus) plays an important role in the pathogenesis of AD. Atopic skin is susceptible to infection with S. aureus. AIM: This study was aimed to compare the skin S. aureus colonisation status and its secretion of superantigens in adult AD and healthy subjects and to evaluate the efficacy of two treatment regimens (oral cefuroxime plus topical betamethasone dipropionate 0.05% versus topical betamethasone dipropionate 0.05%) in AD patients. METHODS: A group of 128 AD and 40 healthy subjects were recruited in this study and treatment efficacy was assessed by the SCORAD score. RESULTS: S. aureus was found in skin lesions in 83.8% of AD patients while only 37.5% of healthy subjects possessed this kind of bacteria in the external nares (p < 0.001). Superantigen production was more common in S. aureus strains isolated from AD than the control group (58.6% versus 6.6%, p = 0.0006) and staphylococcal enterotoxin B was predominant (88.89%). 68 AD patients who had positive cultures with S. aureus were included in a clinical therapeutic trial. The isolated bacteria were all sensitive to cefuroxime. Patients were randomised to receive either oral cefuroxime 500 mg b.i.d. Plus topical betamethasone dipropionate 0.05% twice daily for 2 weeks (so-called group 1, 36 patients) or only topical betamethasone dipropionate 0.05% twice daily for 2 weeks (so-called group 2, 32 patients). The mean SCORAD scores of group 1 at baseline and after 1 and 2 weeks of treatment were 44.61, 26.69 and 16.61, respectively. The corresponding values for group 2 were 43.03, 32.53 and 23.41, respectively. CONCLUSION: The reduction in SCORAD scores was significantly higher in group 1 than group 2 in comparison to the baseline value of each study group (p = 0.003 after 1 week and p < 0.001 at the end of treatment).