EyeWorld Asia-Pacific September 2016 Issue

September 2016 16 EWAP FEATURE Views from Asia-Pacific Cesar ESPIRITU, MD Department of Ophthalmology, Manila Doctors Hospital, UN Avenue, Ermita, Metro Manila, Philippines Tel. no. +632-525-2260 Fax no. +632-558-0888 local 4080 espiritueyemd@mac.com T he 22 cases cited in this article plus one more reported by Lenci et al. ( Case Rep Ophthalmol Online . 2015; Published online 2015), certainly raises issues regarding the use of intracameral antibiotics for prophylaxis in cataract surgery. These are the same issues that have held back the widespread acceptance of this mode of infection prevention and this new adverse reaction may be another blow to advocates of this mode of prophylaxis. The two main issues here are efficacy and safety. Briefly on efficacy and zeroing in on vancomycin. Eye surgeons have used intracameral vancomycin to reduce the risk of postoperative endophthalmitis during routine cataract surgery with claimed excellent results (Anijeet et al. Clin Ophthalmol . 2010;4:321–326) but this practice has not been without controversy and debate. A recent large, retrospective study (Rudnisky et al. Ophthalmology . 2014;121:835–841) suggested that fluoroquinolones were more effective and, with their superior antibacterial activity, this group may very well be the best choice. The second issue is that of safety. When our study on the “Safety of prophylactic intracameral moxifloxacin 0.5% in cataract surgery patients” came out in the Journal of Cataract and Refractive Surgery 2007 issue, the concern then, outside of the efficacy of the antibiotic, was that of having to compound or reconstitute a parenteral preparation for intracameral injection as is the case for vancomycin and cefuroxime. The possibility of inconsistencies in concentrations, particularly that of excessive levels being delivered into the eye that would cause damage (e.g. TASS) was well founded. The use of fixed volume (0.1 ml) extracted from a sterile, self-preserved commercial preparation (Vigamox, Alcon Laboratories, Fort Worth, Texas) that would be directly injected into the eye addressed issues regarding compunding. From the recent discussions, HORV does not represent a toxic reaction but rather an extremely rare type III hypersensitivity reaction to vancomycin similar to vancomycin-associated leukocytoclastic vasculitis and Henoch–Schonlein purpura. Nevertheless, it is still a drug-related reaction and a change in the choice of antibiotic should at least be considered. There is also possible that there may be some cases of HORV that are less severe and have not been detected or reported. A recent case report demonstrated a milder case of HORV that spontaneously resolved without visual sequelae (Lenci et al. Case Rep Ophthalmol Med . 2015;2015:683194). The initiative taken in addressing this problem spearheaded by the ASCRS/ASRS HORV Task Force should be commended and supported. Editors’ note: Dr. Espiritu is a consultant for Alcon. CHAN Tat Keong, MD Senior Consultant and Chairman, Infection Control Committee Singapore National Eye Centre 11 Third Hospital Avenue, Singapore 169751, Singapore Tel. no. +65-6227-7255 Fax no. +65-6226-3395 tatkeongchan@gmail.com H ORV, a recently described clinical entity, is of great clinical relevance because of its devastating and sight-threatening nature as well as its association with intraocular vancomycin. Fortunately, it is a rare complication, considering the widespread prophylactic use of intraocular vancomycin in countries such as the United States. In Singapore, prophylactic vancomycin use in cataract surgery is less popular, partly because methicillin- resistant Staphylococcus aureus (MRSA) ocular infections are not common. For surgeons who administer intracameral antibiotics, cefuroxime, cefazolin or moxifloxacin are usually used. In Singapore, the lack of a commercially- available intracameral antibiotic is a major factor for many surgeons not routinely administering intracameral antibiotics. The presenting features of HORV are very distinctive and surgeons should distinguish this condition from other post-cataract surgery complications such as toxic anterior segment syndrome (TASS) and infectious endophthalmitis. The etiology of HORV, believed to be a type III hypersensitivity reaction, is also uniquely different from that of TASS which results from antibiotic toxicity. The poor visual acuity present in TASS is almost immediately seen whereas the visual loss in HORV has a more delayed onset. Profound corneal edema and excessive anterior chamber inflammation, two common features present in TASS, are usually not seen in HORV. Aminoglycoside ocular toxicity usually affects the macula and rarely the peripheral retina, whereas HORV usually causes diffuse peripheral retinal vascular occlusion. It is laudable and timely that the ASRS and ASCRS have set up a joint Task Force to monitor the prevalence of HORV by setting up an online registry as well as to conduct surveillance surveys among their members. Meanwhile, surgeons who are routinely administering intracameral vancomycin during cataract surgery should remain vigilant and monitor their patients for the possible advent of HORV, rare as the occurrence may be. For surgeons practicing in countries where MRSA infections are not a major problem and who are contemplating the choice of an intracameral antibiotic, cefuroxime and moxifloxacin are viable alternatives. Great care, however, should be exercised during the preparation of non-commercially available versions of intracameral antibiotics in order to prevent possible dosage error and resultant ocular toxicity. Editors’ note: Dr. Chan is a consultant for Alcon, Allergan, and Santen. Clinical alert - from page 15