Colonization of hydrogel lenses with Streptococcus pneumoniae: Risk of development of corneal infiltrates

Purpose. To report the association between colonization of contact lenses w ith Streptococcus pneumoniae and the observation of corneal infiltrative ev ents in a group of patients wearing disposable hydrogel lenses on an extend ed-wear schedule. Methods. In a prospective clinical trial, 330 patients wo re disposable hydrogels on a 6-night extended-wear and replacement schedule . The contact lens, lid, and conjunctival microbiota of these subjects was analyzed at frequent intervals and at the time of an adverse event. Results . Streptococcus pneumoniae was an uncommon isolate and was recovered from o nly one of the 3,763 conjunctival samples, five (0.1%) of the 3,764 lid sam ples, and 33 (0.8%) of the 4,315 contact lens samples. Of the 33 lens sampl es, 10 (30%) were associated with corneal infiltrative events, Many of the events were mild inflammatory responses and resolved rapidly on discontinua tion of lens wear. The presence of S. pneumoniae on the contact lens was as sociated with a significant risk of development of corneal infiltrates (odd s ratio, 3.0; p = 0.0227, logistic-regression analysis). Conclusions. Prese nce of S. pneumoniae on hydrogel lenses is a significant risk factor for th e development of corneal infiltrates.