Abstract: SA-PO798
Kidney AA Amyloidosis in a Liver Transplant Recipient
Session Information
- C3G, TMA, MGRS, Amyloidosis, and More
October 26, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Qian, Long, Yale University, New Haven, Connecticut, United States
- Turner, Jeffrey M., Yale University, New Haven, Connecticut, United States
Introduction
Renal AA amyloidosis is a rare cause of proteinuric AKI occuring in chronic inflammatory states from amyloid A protein deposition in the kidney. AA amyloidosis is rare in immunosuppressed transplant recipients. Such cases can present a diagnostic challenge as potential etiologies include autoimmune disease recurrence, occult infections, and inflammation from graft rejection. We report a case of renal AA amyloidosis in a liver transplant recipient that highlights the spectrum of potential pathologies in such patients.
Case Description
A 34-year-old man with a liver transplant 13 years ago for autoimmune hepatitis/primary sclerosing cholangitis (AIH/PSC) overlap syndrome presented with abdominal pain. Creatinine was newly elevated to 4.5 mg/dL (baseline 1.0) and urine protein creatinine ratio was 5g/g. Kidney biopsy showed deposits positive for Congo red with apple green birefringence, with positive immunohistochemistry for serum amyloid A protein. He had multiple risk factors for AA amyloid including injection drug use, cystic liver lesions on imaging resembling abscesses, and long-standing liver enzyme elevations with prior liver biopsy findings suggestive of recurrent AIH/PSC versus cellular rejection. ANA titer was elevated at 1:1280. Liver-kidney microsomal antibody and smooth muscle antibody were negative. AST, ALT, and ALP fluctuated between normal to elevated. Multiple blood cultures were negative. Direct sampling of the liver lesions was not obtainable due to their small size and difficult anatomical location. The patient received 4 weeks of cefuroxime/metronidazole for potential abscesses, but the liver lesions persisted on repeat imaging. Repeat liver biopsy showed amyloidosis as well as inflammatory changes suggesting AIH/PSC versus rejection. The patient’s immunosuppression was modified: sirolimus was replaced with azathioprine, while tacrolimus and low dose prednisone continued. In addition, losartan was started. The patient abstained from further injection drug use. His creatinine improved to 1.57; proteinuria persisted.
Discussion
AA amyloidosis in an immunosuppressed patient with substance use poses diagnostic challenges. In this case, injection drug use seems a likely cause, as renal function improved with self-reported abstinence. However, the liver lesions remain of unclear etiology, and a potential link between AIH/PSC recurrence and AA amyloidosis remains a consideration.