Light chain deposition disease with renal involvement: clinical characteristics and prognostic factors.

BACKGROUND: Light chain deposition disease (LCDD) is characterized by the tissue deposition of monotypical immunoglobulin light chains (LCs). The aim of this study was to investigate its clinical characteristics and prognostic factors.

METHODS: Multicenter study of LCDD with renal and patient survival analyses.

RESULTS: Sixty-three cases were studied (age: 58 +/- 14.2; males: 63.5%; kappa/lambda deposition: 68/32%; underlying disorders: multiple myeloma [MM] 65%, lymphoproliferative disorders 3%, idiopathic 32%). Ninety-six percent presented with renal insufficiency (acute, 52%; chronic, 44%), and 84% with proteinuria >1 g/d. During the follow-up, 36 patients reached uremia (incidence rate: 23.7/100 patient-years) and 37 died (17.5/100 patient-years). The factors independently associated with a worse renal prognosis were age (relative risk [RR], 1.05; 95% confidence interval [CI], 1.009 to 1.086) and serum creatinine at presentation (RR, 1.24; 95% CI, 1.02 to 1.5). Those independently associated with a worse patient survival were age (RR, 1.06; 95% CI, 1.03 to 1.1), MM (RR, 2.75; 95% CI, 1.22 to 6.2), and extrarenal LC deposition (RR, 2.24; 95% CI, 1.15 to 4.35). While kappa-LC deposition was more frequently associated with nodular sclerosing glomerulopathy, histological parameters were not predictors of renal/patient prognosis. The survival of the uremic patients undergoing dialysis was similar to that of patients not reaching uremia.

CONCLUSION: LCDD is characterized by renal insufficiency with proteinuria and has a severe prognosis. Apart from age, the prognostic factors identified were degree of renal insufficiency at presentation affecting the renal prognosis, underlying hematologic disorder and extrarenal LC deposition affecting the patient prognosis. Dialysis is worth performing in uremic LCDD patients.