Tacrolimus-Induced Neurotoxicity in Early Post-Liver Transplant Saudi Patients: Incidence and Risk Factors

BACKGROUND Tacrolimus is a calcineurin inhibitor (CNI) commonly used as an immunosuppressant to prevent the rejection of organ transplants. After liver transplantation, it can cause early neurological complications, known as early calcineurin inhibitor-induced neurotoxicity (ECIIN). Its management requires CNI withdrawal, a measure that can affect post-transplant outcomes, primarily allograft rejection. In addition, it can negatively impact the quality of life. The incidence and risk factor of ECIIN has not been reported in the Saudi population. We investigated the incidence and risk factors of ECIIN after liver transplant in Saudi patients. We also looked at the length of stay in the Intensive Care Unit, hospital, and 30-day mortality as secondary endpoints. MATERIAL AND METHODS This was a retrospective cohort study of adult patients on tacrolimus with mild, moderate, or severe neurological events within the first month after liver transplantation at a single center of patients who meet the inclusion criteria and were over age 14 years. A total of 338 patients were included in the analysis, and the sample size was calculated based on a pilot study. RESULTS Among 338 liver transplantation patients, 63 patients (19%) developed ECIIN. Forty-eight percent of patients had seizures, 23% had agitation, 21% had psychosis, 10% had severe tremors, 13% had confusion, and 6% developed coma. The median time of the incident to develop ECIIN was 9 (IQR: 5-13.5) days after transplant. Thirty-eight patients were managed by switching to cyclosporine, 12 required a reduction in the dose, and 3 were managed temporarily by discontinuing therapy. Autoimmune hepatitis as an underlying liver disease was one of the statistically significant risk factors (P=0.0311). The median length of hospital stay was 31 (IQR: 21-75.5) days, ICU length of stay was 10 (IQR: 5-20.5) days, and 8 patients died within 30 days after transplant. CONCLUSIONS The incidence of ECIIN in Saud Arabia was similar to that reported in other populations with similar risk factors. Electrolyte imbalance, mainly hyponatremia, was significantly associated with developing ECIIN. Therefore, ECIIN may potentially increase hospital and ICU length of stay.