A staging system for renal outcome and early markers of renal response to chemotherapy in AL amyloidosis

• Published in: Blood Vol. 124; no. 15; pp. 2325 - 2332
• Main Authors: Palladini, Giovanni, Hegenbart, Ute, Milani, Paolo, Kimmich, Christoph, Foli, Andrea, Ho, Anthony D., Rosin, Marta Vidus, Albertini, Riccardo, Moratti, Remigio, Merlini, Giampaolo, Schönland, Stefan
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 09.10.2014
• Subjects: Aged; Amyloidosis - drug therapy; Amyloidosis - pathology; Biomarkers - metabolism; Cohort Studies; Dialysis; Disease Progression; Female; Humans; Immunoglobulin Light Chains - metabolism; Immunoglobulin Light-chain Amyloidosis; Kidney - pathology; Male; Middle Aged; Proportional Hazards Models; Reproducibility of Results; Risk Factors; Survival Analysis; Time Factors; Treatment Outcome
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2014-04-570010

The kidney is involved in 70% of patients with immunoglobulin light-chain (AL) amyloidosis, but little is known on progression or reversibility of renal involvement, and criteria for renal response have never been validated. Newly diagnosed patients from the Pavia (n = 461, testing cohort) and Heidelberg (n = 271, validation cohort) centers were included. Proteinuria >5 g/24 h and estimated glomerular filtration rate (eGFR) <50 mL/min predicted progression to dialysis best. Proteinuria below and eGFR above the thresholds indicated low risk (0 and 4% at 3 years in the testing and validation cohorts, respectively). High proteinuria and low eGFR indicated high risk (60% and 85% at 3 years). At 6 months, a ≥25% eGFR decrease predicted poor renal survival in both cohorts and was adopted as criterion for renal progression. A decrease in proteinuria by ≥30% or below 0.5 g/24 h without renal progression was the criterion for renal response, being associated with longer renal survival in the testing and validation populations. Hematologic very good partial or complete remission at 6 months improved renal outcome in both populations. We identified and validated a staging system for renal involvement and criteria for early assessment of renal response and progression in AL amyloidosis that should be used in clinical practice and trial design. •A staging system based on proteinuria and glomerular filtration rate discriminates patients at different risk of progression to dialysis.•Changes in proteinuria and glomerular filtration rate allow early assessment of renal response to therapy.