MICROBIAL FINDINGS IN SUTURE EROSION AFTER PENETRATING KERATOPLASTY

Purpose: The purpose of the study was to evaluate the presence of micr oorganisms in eroded (broken or loose) sutures post-penetrating kerato plasty (PKP). Methods: Fifty-five consecutive episodes of eroded 10-0 nylon sutures post-PKP in 35 eyes were evaluated. Eroded sutures were removed and, along with a swab from the conjunctiva, studied for aerob ic and anaerobic bacteria. Preoperative diagnosis, elapsed time since surgery, presence of symptoms, suture location, infiltration, vascular ization, and mucous at the suture site were recorded. Student's t test was used for statistical analysis. Results: The average time from PKP to suture removal was 31.6 months. Eyes treated with topical steroids presented earlier suture erosions (P = 0.05). Of the 55 sutures, 34 w ere sterile, and in 21, both Staphylococcus epidermidis and diphtheroi ds (mixed flora) were cultured. Of the 55 conjunctivas, 32 were steril e, 22 showed mixed flora, and 1 had Pseudomonas. Sutures eroded for mo re than 24 hours had more positive cultures than those eroded for 24 h ours or less (P = 0.043). Sutures located superiorly had fewer positiv e cultures than did those in the palpebral fissure area (P = 0.044). E yes with repeated suture erosions had more culture-positive sutures (P = 0.017) and conjunctivas (P = 0.014) at the first erosion in compari son with the second erosion. Infiltration, vascularization, or mucus a t the suture site did not correlate with positive cultures. Conclusion s: Bacteria are encountered at the site of eroded sutures. Patients wi th PKP should report symptoms immediately, and eroded sutures should b e removed as early as possible.