[Laboratory analysis of infectious keratitis in patients following refractive surgery].

PURPOSE To describe the laboratory findings in patients with infectious keratitis, who underwent refractive surgery, correlating the surgical procedure and the time of infection manifestation, and the results of culture and smears. METHODS The previous samples were obtained from patients submitted to radial keratotomy (RK), photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) at the Ophthalmology Department of UNIFESP. The infections were classified as early, when they occurred up to 30 days after the surgery, and late when diagnosed after 30 days. RESULTS In 93 samples, 39 (42%) came from patients submitted to radial keratotomy, 14 (36%) being early infections and 25 (64%) late; 38 (41%) of LASIK, 21 (55%) being early and 17 (45%) late; 16 (17%) of photorefractive keratectomy, 10 (62.5%) being early and 6 (37.5%) late. Eighty-six samples were submitted to culture and smears for bacteria, 43 cultures (50%) and 43 smears (50%) were positive. Seventy-two samples were submitted to culture and smears for fungi, 2 cultures (3%) and 4 smears (6%) were positive. CONCLUSION The agreement between culture and smear results was 80.2%; regarding the type of surgery there was no statistically significant relationship between time of onset of infection and surgery.