Abstract
Purpose: :
Staphylococcal superantigens are a group of high– molecular–weight pyrogenic proteins, and recently been reported to play a significant role as it leads to a worsening of disease severity by producing superantigens that induce a strong proliferation of T cells and favour a T helper type 2–like cytokine profile. The role of staphylococcal superantigens in atopic dermatitis has recently been recognized, and new evidence suggests that similar mechanisms may also be relevant in conjunctiva. Those facts may indicate possibility that alteration of bacterial flora play a crucial role in development of allergic conjunctivitis. In this study, we investigated the bacterial flora in conjunctival sac and its production of enterotoxin, the representative superantigen, in patients with vernal keratoconjunctivitis (VKC) and normal volunteers.
Methods: :
Ten patients (all males; aged 8–27 years) with VKC with corneal epithelial disease, but without infection, were enrolled for this study. Microbial culture of samples collected from conjunctival sac using swabs was performed. For the controls, microbial culture of conjunctival sac was also performed in 6 females and 1 male subjects (aged 22–40 years) with no allergic or infectious eye disease. After staphylococcus is detected Long–term culture, anti–biotics sensitibity test, and assessment for superantigens and coagulase, were examined.
Results: :
Methicillin–sensitive staphylococcus aureus (MSSA) was detected in conjunctival smears from 7 of 10 VKC patients. In 2 of 7 MSSA positive patients, enterotoxin production was observed. In normal controls, MSSA without enterotoxin production was detected from 1 volunteer and coagulase negative staphylococcus was detected in 2 volunteers.
Conclusions: :
MSSA was highly detected in conjunctival smears in patients with VKC. Staphylococcus infection and superantigen production may affect exacerbation of VKC.
Keywords: conjunctivitis • immunomodulation/immunoregulation • microbial pathogenesis: clinical studies