The importance of kidney response over hematologic response in predicting kidney outcome in AL Amyloidosis: a retrospective cohort study

Abstract Background Light chain amyloidosis, characterized by amyloid fibril deposition in multiple organs, often leads to progression to end-stage kidney disease. This study aimed to identify predictors of kidney survival in patients with kidney amyloidosis, focusing on hematologic and kidney response. Methods This retrospective study included 138 patients diagnosed with kidney amyloidosis between 2011 and 2019. Palladini et al.'s criteria were applied for kidney stage and response, and the 2012 International Society of Amyloidosis criteria for hematologic response. Results Overall, 17 (12.3%) progressed to end-stage kidney disease. Multivariate analysis, considering baseline characteristics, revealed that stage Ⅱ was associated with an increased risk of end-stage kidney disease compared to stage Ⅰ (hazard ratio 3.75; 95% confidence interval 1.38–10.15; P = 0.01). Compared to kidney response, the risk of end-stage kidney disease increased by 8.42 (95% confidence interval 1.71–41.35; P = 0.01) and 7.36 (95% confidence interval 1.25–43.33; P = 0.03) times in stable disease and kidney progression at 6 months, independently on baseline characteristics, respectively, whereas hematologic response showed no association with kidney outcome. Kidney survival was longer in patients with both deep hematologic response and kidney response than in those with only hematologic response (P = 0.004). Conclusion The study underscores the importance of kidney response over hematologic response in predicting end-stage kidney disease and emphasizes the need to assess treatment endpoints, considering organ response alongside hematologic response.