Study on the effectiveness of antibiotic prophylaxis in external dacryocystorhinostomy: a review of 697 cases.

PURPOSE To evaluate the prophylactic use of antibiotics in external dacryocystorhinostomy for the prevention of postoperative complications. METHODS This study included 697 patients diagnosed with distal nasolacrimal duct obstruction and who were operated on by the same surgeon. Direct culture of the lacrimal sac content was carried out. Data were collected regarding clinical signs and symptoms, use of intraoperative antibiotics, results of culture samples obtained during surgery, and antibiogram analysis. Also, the postoperative period was analyzed with regard to the presence of postoperative complications. RESULTS Out of 697 patients, 536 were women. The mean age at surgery was 67.0 ± 13.3 years. Prior to surgery, 19.5%, 18.5%, 11%, and 17.8% of patients showed recurrent conjunctivitis, mucocele, mucopyocele, and episodes of acute dacryocystitis, respectively. Seventy-three patients did not receive prophylactic treatment during surgery. A total of 8.3% of lacrimal sacs were culture positive, the most commonly isolated organism being Staphylococcus aureus. The use of antibiotics during surgery was not associated with a lower rate of postoperative complications. A statistically significant association was found between some clinical pictures, such as mucocele, mucopyocele, and dacryocystitis, and a higher rate of positive cultures. CONCLUSIONS This study questions the generalized use of prophylactic antibiotics for external dacryocystorhinostomy, while providing evidence to indicate their use for patients who have had prior episodes of mucocele, mucopyocele, or acute dacryocystitis.