MON-165 A Case of Tacrolimus-Induced Posterior Reversible Encephalopathy Syndrome

Abstract

This case demonstrates posterior reversible encephalopathy syndrome (PRES) as a rare neurotoxic adverse effect of tacrolimus. A 49 year-old lady presented with reduced level of consciousness and upper limb jerking on background of recent kidney transplantation three weeks prior to presentation. Among her medical history, she has end-stage renal failure secondary to kidney agenesis, hypothyroidism, anxiety/depression, restless legs syndrome and history of opioid misuse. On admission, her immunosuppressants were tacrolimus 6mg BD, mycophenolate mofetil 1g BD and prednisolone 20mg daily. Following failure of naloxone trial, she was admitted to intensive care and loaded with phenytoin as seizure prophylaxis. Initial serial brain imaging, lumbar puncture and seizure study showed brain changes suggestive of PRES. Furthermore, despite its rarity, tacrolimus use was concluded as the main cause of patient’s presentation. Tacrolimus was ceased and sirolimus was commenced as an alternative immunosuppressant. Due to its major potential to augment sirolimus clearance, phenytoin therapy was ceased following pharmacist intervention and with neurology advice. Sirolimus level was monitored regularly and the dose was up-titrated to therapeutic level. Additionally, blood pressure control was tightly monitored as hypertension is a known risk factor for PRES. Multiple antihypertensives (perindopril, amlodipine and prazosin) were used to provide satisfactory blood pressure readings. With conservative management and repeat brain studies, patient fully recovered and was discharged with close follow-ups from transplant and neurology teams. This report enhances clinical recognition of PRES as a potential adverse effect of tacrolimus use in the setting of solid-organ transplantation.