Abstract
BACKGROUND: To report a very rare acute cystoid macular oedema following ganciclovir injection in patients receiving allogeneic haematopoietic stem cell transplantation. CASE PRESENTATION: A 44-year-old male patient experienced vision loss in his left eye eight months after allogeneic stem cell transplantation. Ophthalmologic examination showed posterior retinopathy with retinal haemorrhage, a yellow necrotic border, and a vascular white sheath involved in the superior temporal retina but not the posterior pole. Cytomegalovirus DNA results in both plasma and ocular fluid were positive. All tests combined with the patient's medical history suggested that his ocular disease was cytomegalovirus retinitis. Consequently, he received a weekly ganciclovir vitreous injection. The disease was visibly controlled, and the fundus condition improved after the first three treatments. However, the patient had severe vision loss in his left eye and acute cystic oedema in the macula, while the original lesion was stable two hours after the fourth treatment. The macular oedema subsided significantly on the first day. Over the next week, daily OCT findings indicated that the patient's macular oedema gradually subsided and resolved completely by the second week, and his left eye vision partially improved. CONCLUSION: Macular oedema may occur in patients with cytomegalovirus retinitis, but it rarely occurs during treatment. In this case, the patient's macular oedema appeared and resolved quickly. Macular oedema in patients with cytomegalovirus retinitis receiving vitreous cavity injections of ganciclovir needs to be further studied and discussed.