A 55-year-old man presents to the transplant clinic with a 3-day history of fatigue, dark urine, and low-grade fever. He underwent an orthotopic liver transplant 8 weeks ago for alcohol-associated cirrhosis. His current immunosuppressive regimen includes tacrolimus, mycophenolate mofetil, and prednisone. His temperature is 38.1°C (100.6°F), blood pressure is 130/80 mmHg, and heart rate is 90/min. Physical examination reveals scleral icterus and mild right upper quadrant tenderness. Laboratory tests show significantly elevated aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and total bilirubin compared to his baseline from two weeks ago. Tacrolimus trough levels are within the target therapeutic range. The physician suspects acute cellular rejection. Arrange the following diagnostic and therapeutic steps in the most appropriate sequential order for evaluating and managing this patient's presentation.
- 1Perform hepatic Doppler ultrasonography
- 2Obtain a percutaneous liver biopsy
- 3Administer high-dose intravenous methylprednisolone
- 4Administer anti-thymocyte globulin