A risk stratification for systemic immunoglobulin light-chain amyloidosis with renal involvement

Renal involvement is found in about 70% of patients with systemic immunoglobulin light-chain (AL) amyloidosis. However, there is no risk stratification system specialized for renal AL concerning patients' survival. Galectin-3 (Gal-3) has been reported to portend poor prognosis in other renal diseases. We measured Gal-3 and several traditional risk biomarkers of AL in baseline samples from 253 consecutive patients diagnosed with renal AL. At baseline, Gal-3 [Hazard ratio (HR): 1·46; P = 0·033], high-sensitivity cardiac troponin T (hs-cTnT) (HR: 2·65; P < 0·001) and difference between involved and uninvolved free light chains (dFLC) (HR: 1·81; P = 0·001) were independent predictors of all-cause mortality. The cut-off points for Gal-3, hs-cTnT, and dFLC were 20·24 ng/ml, 0·026 ng/ml, and 75·89 mg/l, respectively. Patients were stratified into four stages by assigning a score of 1 for each of the three biomarkers above the cut-off point. The proportions of patients with disease stages 1, 2, 3 and 4 were 17·0%, 37·2%, 29·2% and 16·6%, and the median overall survival times from diagnosis were 100, 60, 29 and 15 months, respectively (P < 0·01). Higher level of Gal-3 is associated with increased risk for mortality, and the risk stratification based on Gal-3 is a reliable model for predicting mortality in AL amyloidosis with renal involvement.