Local, systemic risk factors, older age led to higher rate of preoperative bacterial contamination

Eur J Ophthalmol. 2009;19:717-722.

Older age and local and systemic risk factors such as chronic topical medical use, contact lens wear and diabetes were among factors that contributed to higher rates of bacterial conjunctival contamination before intraocular surgery, a study found.

The prospective, masked study examined 1,474 consecutive patients who underwent intraocular surgery. Four groups of patients were created — a control group that had no local or systemic risk factors; a group that had local risk factors of chronic topical medication use, contact lens wear, blepharitis, chronic eyelid and conjunctival inflammation; a group with systemic risk factors of immunosuppression, diabetes, autoimmune conditions and asthma; and a group with both local and systemic risk factors.

Preoperative conjunctival cultures were taken.

The study found 914 bacteria in 214 patients. Of those cases, advanced age was "associated with a higher rate of positive conjunctival cultures (P < .005)," the study authors said.

"Among the 282 patients in the control group, 14 (5%) had a positive conjunctival culture," they said. "Compared to the control group, positive conjunctival cultures were found in 118 out of 503 patients (23.5%) with local risk factors (P < .0001), 65 out of 545 patients (11.9%) with systemic risk factors (P = .0019) and 22 out of 144 (15.3%) with both (P = .0006)."

Gender showed no statistical role in cases, the study found.