Brief report Post‒cataract surgery endophthalmitis outbreak caused by multidrug-resistant Pseudomonas aeruginosa Helena C. Maltezou MD a, * , Olga Pappa MD b , Georgios Nikolopoulos DDS a , Lemonia Ftika MD a , Antonios Maragos RN a , Helen Kaitsa MD c , Efthimia Protonotariou MD d , Eudoxia Diza MD d , Nikolaos Georgiadis MD e , Alkiviadis Vatopoulos MD b, f , Pavlos Nicolaidis MD g a Department for Interventions in Health Care Facilities, Hellenic Center for Diseases Control and Prevention, Athens, Greece b Central Public Health Laboratory, Hellenic Center for Diseases Control and Prevention, Athens, Greece c Department of Microbiology, Theageneio Hospital, Thessaloniki, Greece d Department of Microbiology, AHEPA University Hospital, Thessaloniki, Greece e Department of Ophthalmology, AHEPA University Hospital, Thessaloniki, Greece f Department of Microbiology, National School of Public Health, Athens, Greece g First Department of Internal Medicine, AHEPA University Hospital, Thessaloniki, Greece Key Words: Epidemic Nosocomial Eye Cataract In June 2010, a severe outbreak of 13 cases of postecataract surgery endophthalmitis caused by multidrug-resistant Pseudomonas aeruginosa occurred. Pulse-field gel electrophoresis in eye isolates found 95% genetic similarity; however, extensive environmental and carriage investigation revealed no source of infection. Copyright Ó 2012 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved. Cataract surgery is among the most common surgeries, with an estimated 10 million surgeries performed annually worldwide. 1 Post‒cataract surgery endophthalmitis (PCSE) is a detrimental complication that usually causes severe visual impairment and even eye loss in some cases. A systemic review of 3,140,650 cataract extractions from 1963-2003 revealed an overall PCSE incidence rate of 0.128%. 2 Usually PCSE cases occur sporadically; however, outbreaks have occurred, and the sources of infection have been traced to contaminated surgical instruments, materials and solu- tions, ventilation systems, and disruption of infection control measures. 3-10 We describe an outbreak of 13 PCSE cases caused by a multidrug-resistant (MDR) Pseudomonas aeruginosa strain. METHODS The outbreak occurred in a 60-bed private hospital. Between December 2005 and June 2010, 1,093 cataract surgeries were per- formed using phacoemulcification through a sutureless incision followed by intraocular lens implantation. The cataract surgeries were performed in 2 operating rooms on 2 consecutive days each week by 4 surgeons, 1 anesthesiologist, and 1 nurse. The personnel used 7.5% povidone-iodine scrub for surgical antisepsis and 80% alcohol-based antiseptic for hand disinfection, and changed sterile gloves, gowns, and surgical masks between surgeries. Povidone- iodine solution 10% in 240-mL bottles was applied to the eye before and after surgery. The same bottle was used for multiple patients who underwent surgery on the same day, and it was dis- carded at the end of the day. Cefuroxime was infused in the anterior chamber, and tobramycin ointment was applied to the eye post- operatively. Surgical instruments were sterilized at 134  C for 18 minutes. All other instruments (eg, prefilled syringes) were disposable. Personnel, surgical technique, and hygiene procedures did not change during the study period. An unmatched case-control study of patients who underwent sugery during January-June 2010 was conducted. A PCSE case was defined as a patient with clinically diagnosed endophthalmitis (eg, blurred vision, eye pain, conjunctival injection, hypopion). Controls were selected randomly among the patients without PCSE. Demo- graphic, clinical, and operational data were collected. Swab cultures were collected from the vitreous humor of 12 patients. Pharyngeal and rectal swabs were collected from opera- tive personnel for carriage testing. Forty-one environmental * Address correspondence to Helena C. Maltezou, MD, Department for Inter- ventions in Health Care Facilities, Hellenic Center for Disease Control and Preven- tion, 3-5 Agrafon Street, Athens, Greece. E-mail address: helen-maltezou@ath.forthnet.gr (H.C. Maltezou). Conflict of interest: None to report. Contents lists available at ScienceDirect American Journal of Infection Control journal homepage: www.ajicjournal.org American Journal of Infection Control 0196-6553/$36.00 - Copyright Ó 2012 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved. doi:10.1016/j.ajic.2011.02.007 American Journal of Infection Control 40 (2012) 75-7