Iu Lawrence P L, Fan Michelle C Y, Lam Wai-Ching, Wong Ian Y H
Department of Ophthalmology, The University of Hong Kong, Grantham Hospital, 125 Wong Chuk Hang Road, Aberdeen, Hong Kong, Hong Kong.
BMC Ophthalmol. 2018 Feb 9;18(1):36. doi: 10.1186/s12886-018-0703-8.
Cytomegalovirus (CMV) retinitis is an opportunistic infection that primarily affects immunocompromised individuals. Intravitreal ganciclovir injection monotherapy or in combination with systemic anti-CMV therapy are effective treatments for CMV retinitis. Crystallization of ganciclovir after intravitreal injection is extremely rare. Only two cases had been reported in literature. Crystallization in only one eye after bilateral injections had not been reported before. We hereby report a case of intraocular ganciclovir crystallization in one eye after bilateral intravitreal injections, and repeated crystallization in the same eye after repeated injections.
A 79-year-old patient had bilateral cytomegalovirus retinitis and received bilateral intravitreal ganciclovir injections of 2.5 mg in 0.05 ml sterile water. Fundus examination after injection showed formation of needle-shaped, golden-yellow crystals in the vitreous of right eye but not in left eye. The crystals dissolved spontaneously. Repeated bilateral intravitreal ganciclovir injections 4 days later resulted in repeated crystallization of ganciclovir in right eye but not in left eye. The crystals dissolved spontaneously and completely after 5 minutes. Visual acuity remained unchanged and intraocular pressure was normal.
Intraocular ganciclovir crystallization could occur after intravitreal injections. It is important to perform fundus examination after injection. The crystals may dissolve rapidly and vitrectomy may not be necessary. Our case suggested intraocular ganciclovir crystallization is an idiosyncratic phenomenon, subjects to distinctive intraocular environment which could be different between two eyes of the same patient. The susceptible intraocular environment could be persistent leading to repeated crystallization.
巨细胞病毒（CMV）视网膜炎是一种主要影响免疫功能低下个体的机会性感染。玻璃体内注射更昔洛韦单一疗法或联合全身抗CMV治疗是CMV视网膜炎的有效治疗方法。玻璃体内注射后更昔洛韦结晶极为罕见。文献中仅报道过两例。双侧注射后仅一只眼睛出现结晶此前尚未见报道。我们在此报告一例双侧玻璃体内注射后一只眼睛出现眼内更昔洛韦结晶，且重复注射后同一眼睛再次出现结晶的病例。
一名79岁患者患有双侧巨细胞病毒视网膜炎，接受了双侧玻璃体内注射2.5毫克更昔洛韦（溶于0.05毫升无菌水中）。注射后眼底检查显示右眼玻璃体中形成针状、金黄色晶体，而左眼未出现。晶体自行溶解。4天后重复双侧玻璃体内注射更昔洛韦导致右眼再次出现更昔洛韦结晶，左眼未出现。5分钟后晶体自行完全溶解。视力保持不变，眼压正常。
玻璃体内注射后可能发生眼内更昔洛韦结晶。注射后进行眼底检查很重要。晶体可能迅速溶解，可能无需进行玻璃体切除术。我们的病例表明眼内更昔洛韦结晶是一种特异质现象，取决于独特的眼内环境，同一患者的两只眼睛可能不同。易感的眼内环境可能持续存在，导致反复结晶。
