A Comparison Study of the Staphylococcal Exotoxins and Staphylococcal Enterotoxin A-specific IgE Antibody between Childhood and Adulthood Atopic Dermatitis

ABSTRACT

BACKGROUND: The skin of patients with atopic dermatitis (AD) exhibits a striking susceptibility to colonization with Staphylococcus aureus (S. aureus). Superantigens produced by S. aureus and their specific IgE antibodies are thought to be important precipitating factors of AD, but there are few reports evaluating these 2 factors at the same time, particularly in adult AD patients. OBJECTS: Our purpose was to investigate the differences in the culture degree of S. aureus from the lesion, non-lesion, and control group of child and adult AD patients, to research the correlation between the exotoxin production, total IgE, anti-SEA IgE and the disease severity by SCORAD index, to ascertain the differences between child and adult AD patients. METHODS: The clinical severity of 30 child (2 to 15 years of age) and 30 adult patients (16 to 40 years of age) with AD was evaluated by using SCORAD index. S. aureus was isolated from lesional and non-lesional skin of AD patients, and from healthy controls. Staphylococcal exotoxins were detected by using reversed passive latex agglutination toxin detection kits. Anti-SEA IgE antibody was determined by using AlaSTATt assay RESULTS: S. aureus colonizations were found in 11 (36.7%) of the lesional skin, in 5 (16.7%) of the non-lesional skin of 30 child AD patients, and in 26 (86.7%), in 20 (66.7%) of 30 adult AD patients, respectively. The colonization rates of S. aureus in child patients were much lower than those in adult patients, both form lesional skin and non-lesional skin. Staphylococcal exotoxins were detected in 5 (45.5%) of the 11 colonizations from lesional skin, in 2 (40%) of the 5 colonizations from non-lesional skin of children, and in 10 (38.5%) of the 26 colonizations, in 9 (45%) of the 20 colonizations of adults, respectively. Staphylococcal enterotoxin A (SEA) was most frequently detected in both groups. S. aureus colonization was correlated with the severity of AD in childhood, but not in adulthood. However, there were no statistical significances between severity of AD and others such as exotoxin production, and the level of total IgE and anti-SEA IgE in both groups. CONCLUSION: The colonization of S. aureus was more common in adult AD patients than child AD patients. Anti-SEA IgE level was much higher in adult AD patients than in child AD patients. It is tempting to speculate that the colonization of S. aureus and exotoxin production might be related to the disease. duration rather than clinical severity of AD.