Long-Term Serum Amyloid A Profile in Clinically Stable Pediatric Liver Transplant Recipients

Serum amyloid A (SAA) is an acute-phase protein whose sustained elevation is required for AA amyloid fibril formation. Although AA amyloidosis is a rare complication of solid organ transplantation, the long term SAA profile of clinically stable pediatric liver transplant recipients remains unknown. This study aimed to characterize long-term SAA concentrations in this population.

This observational study included 51 pediatric liver transplant recipients and 50 children with acute febrile infections. Cross-sectional SAA measurements were obtained in clinically stable recipients at least 6 months after transplantation. Children with acute febrile infections served as a high-inflammation reference group. In addition, 7 recipients underwent serial SAA measurements before transplantation and at 1 week, 1 month, and 6 months after transplantation.

Median SAA concentrations were significantly lower in clinically stable transplant recipients than in children with acute infection (4.2 mg/L [0.7-71.8] vs. 172 mg/L [1.5-961], P < .001). SAA concentrations ≥10 mg/L were observed in 14% of transplant recipients and 96% of children with acute infections. In the longitudinal subgroup, SAA concentrations increased during the early postoperative period and declined toward baseline by 6 months (P = .014).

SAA concentrations were generally low in clinically stable pediatric liver transplant recipients during long-term follow-up but were substantially higher in children with acute infections. These findings provide insight into long-term SAA concentrations in this population and address an important gap in the literature.