Two Cases of Tacrolimus-related Transplant-associated Thrombotic Microangiopathy Retinopathy after Allogenic Peripheral Blood Stem Cell Transplantation

Purpose: We report two cases of tacrolimus-related transplant-associated thrombotic microangiopathy (TA-TMA) retinopathy in leukemia patients who had undergone allogenic peripheral blood stem cell transplantation (PBSCT). Case summary: (Case 1) A 58-year-old woman with a history of PBSCT due to acute myelocytic leukemia and taking tacrolimus was referred to the ophthalmology clinic with visual disturbance. Her visual acuity (VA) was 0.4 in the right eye and 0.5 in the left eye. Multiple cotton wool spots and retinal hemorrhages were found in both eyes on fundus examination. Multiple capillary non-perfusions were seen on fluorescein angiography (FA). Tacrolimus-related TA-TMA retinopathy was suspected. Tacrolimus was discontinued and plasmapheresis was performed. After 3 months, neovascular glaucoma developed and her VA became "counting fingers" at 20 cm in both eyes. (Case 2) A 20-year-old man with a history of PBSCT due to acute lymphocytic leukemia and taking tacrolimus was referred to our clinic because of decreased VA in both eyes. His VA was 0.05 in the right eye and 0.025 in the left eye. Fundus and FA findings were the same as in Case 1, and the patient was suspected to have tacrolimus-related TA-TMA retinopathy. Tacrolimus was discontinued and plasmapheresis was performed. His VA was 0.2 in the right eye and 0.4 in the left eye at 1 month after treatment. Conclusions: It is necessary to consider TA-TMA retinopathy in leukemia patients taking calcineurin inhibitors, such as tacrolimus, who have decreased VA. Early diagnosis and treatment are important.