Bacterial contamination of intraocular lenses: the source of the bacteria

In order to investigate potential sources for the bacterial contamination of intraocular lenses, specimens were taken for culture from a variety of sites. A swab from the lid margin, the operating room air, an intraocular lens which was allowed to rest on the eye, and the sodium hyaluronate were cultured during routine intercapsular lens implant surgery on 31 patients. Positive cultures were obtained from six intraocular lenses. Subtyping by three independent methods showed that isolates from five of these lenses were indistinguishable from bacteria cultured from the air. In the case of the sixth lens a bacterial isolate from the lid margin matched with that from the lens. Staphylococcus epidermidis was cultured from four lenses; Staphylococcus haemolyticus was also isolated from one of these four lenses and the remaining two lenses produced isolates of Staphylococcus aureus.