Work

Tacrolimus-Induced Thrombotic Microangiopathy in Orthotopic Heart Transplant Patients

Year: 2025

Type: article

Abstract: BACKGROUND: Thrombotic microangiopathy (TMA) is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and organ damage from microvascular injury. Tacrolimus-induced TMA, although rare in heart transplant recipients, presents diagnostic and management challenges. CASE SUMMARY: We present 3 cases of postorthotopic heart transplant patients on tacrolimus who developed TMA, presenting with new-onset anemia, elevated lactate dehydrogenase, low haptoglobin, and schistocytes. All patients had elevated tacrolimus levels and responded to discontinuation, transitioning to alternative immunosuppressants like sirolimus or everolimus. Kidney function and hematologic abnormalities improved with therapy adjustments. DISCUSSION: Tacrolimus-induced TMA, although infrequent in heart transplant patients, requires a high index of suspicion. Diagnosis can be difficult due to complex clinical histories, complex medication regimen, and variable time of onset. Early identification and tacrolimus discontinuation are essential for favorable outcomes. TAKE-HOME MESSAGES: Tacrolimus-induced TMA is a rare but serious complication in heart transplant patients. Timely diagnosis and tacrolimus cessation are crucial for optimal outcomes.

Source: JACC Case Reports

DOI: 10.1016/j.jaccas.2025.103790