A Report of an Outbreak of Postoperative Endophthalmitis
WITAYA SWADDIWUDHIPONG,M.D.*, RUNGNAPA PRASANTONG, M.D.**, PONGTHEP WONGWATCHARAPAIBOON, M.D.** PlY A LINLAWAN, M.D.**, ROONGRUENG KITPHA Tl, M.D.**,
Affiliation : * Department of Community and Social Medicine, Mae Sot General Hospital, Tak 63110, ** Field Epidemiology Training Program, Division of Epidemiology, Ministry of Public Health, Nonthaburi 11000, Thailand.
We report an outbreak of endophthalmitis following cataract extraction or secondary intraocular lens (IOL) implantation in a 400-bed general hospital in northern Thailand. From December 1997 to September 1998, of 329 patients who had undergone cataract extraction or secondary IOL implantation in the hospital, 31 (9.4%) developed postoperative endophthalmitis. The interval between the operation and the clinical diagnosis of endophthalmitis ranged from 5 to 74 days with a median of 15 days. Of the 31 cases of endophthalmitis, 18 occurred in phacoemul- sification (PE) with IOL, 11 in extracapsular cataract extraction (ECCE) with IOL, and 2 in secondary IOL implantation. Patients who had undergone PE with IOL had a significantly higher rate (12.4%) than those of ECCE with IOL (6.3%). The infection rates also increased with the order of the operations within each operation period (morning or afternoon); later operations were at higher risk. Our findings detected defects in sterilization for the surgeries including possible inadequacy in the autoclave sterilization of surgical instruments, insufficient exposure time with 2 per cent activated glutaraldehyde solution (about 15-30 minutes) for sterilizing some surgical instruments, and the use of multiple-dose intraocular irrigating solution. This outbreak of endophthalmitis emphasizes the necessity to monitor regularly the practice of sterilization/ disinfection in hospitals for prevention and control of nosocomial infections.
Keywords : Endophthalmitis, Nosocomial Outbreak, Sterilization
