Tuberculum sellae meningioma with possible tacrolimus neurotoxicity manifesting as manic-like psychosis after kidney transplantation

Tacrolimus-Induced Neurotoxicity After Transplant: A Literature Review

Tacrolimus, a calcineurin inhibitor, is an immunosuppressant used globally to prevent rejection after organ transplantation. Although it significantly improves outcomes for solid organ transplant patients, it is associated with various side effects such as nephrotoxicity and neurotoxicity. Tacrolimus-induced neurotoxicity is frequently encountered in clinical practice and can present with a variety of symptoms that may occur even at therapeutic levels. Although tacrolimus-induced neurotoxicity is well documented, there is limited literature available on pharmacologic management. Twenty-eight case reports of tacrolimus-induced neurotoxicity were identified and analyzed in addition to other literature including reviews, retrospective studies, and animal model studies. The severity of cases of tacrolimus-induced neurotoxicity reported ranged from mild symptoms that could be managed with symptomatic treatment to conditions such as posterior reversible encephalopathy syndrome and chronic inflammatory demyelinating polyradiculoneuropathy that may require more immediate intervention. This information was utilized in addition to clinical experience to compile potential management options for prevention and treatment of neurotoxic adverse events. This review is limited by the utilization of primarily retrospective studies and case reports. The available literature on the subject is largely narrative and there are no guidelines on treatment of tacrolimus-induced neurotoxicity at the time of this research. This comprehensive review may guide further studies to investigate the pathophysiology of tacrolimus-induced neurotoxicity and to define patient-specific strategies for mitigation or minimization of neurotoxicity. This is especially important given that management of tacrolimus-induced neurotoxicity can include changes to immunosuppression that can result in an increased risk of rejection.

Delayed-Onset Psychosis Secondary to Tacrolimus Neurotoxicity After Lung Transplant: A Case Report and Systematic Review

BACKGROUND

Tacrolimus is the most common immunosuppressant used after transplant, yet it can result in moderate-to-severe neurotoxicity in up to 32% of patients. Signs of neurotoxicity can vary from mild (tremor or headache) to severe (posterior reversible encephalopathy syndrome or psychosis. Prompt recognition and management is needed to lead to symptom resolution.

OBJECTIVE

The objective of this study is to describe the clinical presentation of tacrolimus-induced psychosis, a type of tacrolimus-inducted neurotoxicity, and distinguish it from other central nervous system disturbances, including delirium.

METHODS AND RESULTS

We present a case of delayed onset tacrolimus-induced psychosis with focus on unique clinical features and management strategies. We conducted a systematic review of cases of tacrolimus-induced psychosis using the PubMed database and included 15 manuscripts in our review.

CONCLUSIONS

Tacrolimus-induced psychosis is a unique presentation of tacrolimus-related neurotoxicity and can present without the cardinal symptoms of delirium. The data on isolated psychotic symptoms are limited with current literature focusing on more common presentations of tacrolimus-induced neurotoxicity, such as delirium and tremor. Development of psychosis can occur later in the treatment course and at normal tacrolimus serum levels. It can improve with antipsychotic therapies, but primary management should include cross-titration to an alternate immunosuppressant regimen.

Tacrolimus-induced neurotoxicity from bipolar disorder to status epilepticus under the therapeutic serum level: a case report

BACKGROUND

Tacrolimus is a macrolide immunosuppressant widely used to prevent rejection after solid organ transplantation. In general, adverse events of tacrolimus occur more often as the concentration of tacrolimus in the blood increases. We report the case of a 39-year-old man who developed a variety of adverse events despite in the therapeutic level of tacrolimus in the blood.

CASE PRESENTATION

A 39-year-old man underwent liver transplantation for liver cirrhosis due to alcoholic liver disease. The postoperative immunosuppressant consisted of tacrolimus (5 mg) and mycophenolate (500 mg) twice daily. Five months after taking tacrolimus, he presented with talkativeness, which gradually worsened. Brain magnetic resonance imaging performed 10 months after tacrolimus administration revealed a hyperintense lesion affecting the middle of the pontine tegmentum on T2WI. The blood concentration of tacrolimus was 7.2 ng/mL (therapeutic range 5-20 ng/mL). After 21 months, he exhibited postural tremor in both the hands. Twenty-four months after taking tacrolimus, he showed drowsy mentality, intention tremor, and dysdiadochokinesia. Electroencephalography presented generalized high-voltage rhythmic delta waves; therefore, tacrolimus was discontinued in suspicion of tacrolimus-induced neurotoxicity, and anticonvulsive treatment was started. The level of consciousness gradually improved, and the patient was able to walk independently with mild ataxia.

CONCLUSION

This case shows that tacrolimus-induced neurotoxicity can occur even at normal concentrations. Therefore, if a patient taking tacrolimus exhibits psychiatric or neurologic symptoms, neurotoxicity should be considered even when the blood tacrolimus is within the therapeutic range.