Detection of staphylococcal superantigens from contact-lens-induced inflammatory diseases.

PURPOSE: We investigated the correlation between the production of superantigens in Staphylococcus-aureus-induced ulcer and contact-lens-induced peripheral ulcer (CLPU) and infiltrative keratitis (IK).

METHODS

Twenty-five S. aureus strains used in the study were isolated either from CLPU cases (six), or IK events (13) or asymptomatic eyes (six). A polymerase chain reaction (PCR) was employed to detect genes for superantigenic staphylococcal enterotoxins A-D, toxic shock syndrome toxin-1 and exfoliative toxins A and B. Reversed passive latex aggregation, enzyme-linked immunosorbent assay (ELISA) and immunoblot were used to examine the production of staphylococcal enterotoxins A-D and toxic shock syndrome toxin-1.

RESULTS

The frequency of the superantigenic genes was not significantly different among the clinical isolates when asymptomatic isolates were compared with the strains isolated from CLPU and IK events. ELISA and immunoblot showed non-specific protein cross-reactions.

CONCLUSIONS

The results suggest that detection of superantigenic toxin genes in ocular strains of S. aureus by PCR is a specific, sensitive, rapid and inexpensive alternative to traditional immunological assays. The role, if any, of the S. aureus superantigens in the production of CLPU/IK remains uncertain.