The relationship between Staphylococcus aureus and atopic keratoconjunctivitis

PURPOSE: To investigate the role of Staphylococcus aureus in patients with vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC) complicated by atopic dermatitis (AD). SUBJECTS AND METHODS: Microbiological culture from the conjunctival sac of acute exacerbated patients with VKC and AKC complicated by AD was performed. The subjects were 29 patients (31 eyes) with VKC and AKC who showed acute exacerbated clinical symptoms of conjunctivitis. Antigen specific IgE antibodies to staphylococcal enterotoxin A (SEA) and staphylococcal enterotoxin B (SEB) in serum were also examined. In this study, the patients were divided into two groups: An AD group consisting of 22 patients with VKC and AKC complicated by AD, and a control group consisting of 8 patients with allergic conjunctivitis without AD. We also examined SEA/SEB specific IgE antibody in tears from the 5 patients who underwent bacteriological examinations of the conjunctival sac at the same time. RESULTS: Twenty-seven out of 31 eyes were gram-positive in the bacteriological culture from the conjunctival sac (87.1%). Staphylococcus aureus was detected in 21 out of the 27 eyes (77.8%). In the AD group, 2 of the 22 cases were gram-positive for serum SEA specific IgE antibodies, 2 cases of the 22 cases were gram-positive for SEB specific IgE antibodies, and 9 cases were gram-positive for both SEA and SEB specific IgE antibodies. Serum SEA and SEB specific IgE antibodies were all gram-negative in the control group. Either SEA or SEB specific IgE antibody in tears was detected in all of the above 5 patients who underwent bacteriological examinations of the conjunctival sac, and 4 of the 5 were gram-positive. Staphylococcus aureus was isolated in 3 out of the 5 patients, and 1 case was gram-negative. CONCLUSION: Staphylococcus is one of the exacerbating factors in VKC and AKC. It is important to evaluate both bacteriological examinations of the conjunctival sac and SEA/SEB specific IgE in tears.