Optic neuropathy after long-term treatment with tacrolimus — a case series

Introduction. Optic neuropathy is a rare but severe complication of tacrolimus treatment. We present a case series of patients with optic neuropathy after long-term tacrolimus therapy who underwent organ transplantation.Material and methods. The study included 4 patients (8 eyes) who were diagnosed with optic neuropathy in the course of tacrolimus treatment conducted due to a kidney transplant (3 patients) and a liver transplant (1 patient). Each patient underwent an ophthalmic examination (best corrected visual acuity test, applanation tonometry, slit-lamp examination,visual field test) at the time of visual acuity decline and half a year afterward. Additionally, at the second examination, spectral-domain optical coherence tomography (SD-OCT), evaluating the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer complex (GCL-IPL), was performed.Results. During the first examination, the anterior segment and fundus were unremarkable except for papilledema in the affected eye. Visual acuity, half a year after the onset of neuropathy, was close to the initial state. Intraocular pressure remained stableduring the entire time of follow-up. In the perimetric examination, the neuropathy-affected eye was characterized by concentric narrowing of the visual field during the whole follow-up period. On SD-OCT, in all examined patients, we observed a persistent statistically significant decline in the mean thickness of the RNFL and GCL-IPL. In the case of the RNFL (around the optic disc), injury to superior and inferior sectors prevailed.Conclusion. Tacrolimus-associated optic neuropathy can be observed years after transplantation and with the absence of toxic blood levels. SD-OCT is a quick and non-invasive method of tacrolimus-associated optic neuropathy assessment