The macrophage paradox in renal AL amyloidosis: lessons from histology and imaging

In renal amyloid light chain amyloidosis, sustained and deep hematologic response drives organ response that continues to improve over time. Rauf et al. demonstrate that macrophage infiltration in kidney biopsies portends progression to renal replacement therapy despite hematologic response, whereas amyloid regression on serum amyloid P component scintigraphy independently predicts favorable outcomes. These findings offer insights into the mechanisms of renal involvement and highlight the complex, context-dependent role of macrophages in amyloid clearance and tissue injury.