International Journal of Nephrology and Renovascular Disease (May 2022)
Light Chain Cast Nephropathy in Multiple Myeloma: Prevalence, Impact and Management Challenges
Abstract
Paolo Menè,1 Antonella Stoppacciaro,2 Silvia Lai,3 Francescaromana Festuccia4 1Division of Nephrology, Department of Clinical and Molecular Medicine, “Sapienza” University, Rome, Italy; 2Division of Pathology, Department of Clinical and Molecular Medicine, “Sapienza” University, Rome, Italy; 3Division of Nephrology, Department of Translational and Precision Medicine, “Sapienza” University, Rome, Italy; 4Division of Nephrology, Department of Internal Medicine, Sant’Andrea University Hospital, Rome, ItalyCorrespondence: Paolo Menè, Division of Nephrology, Department of Clinical and Molecular Medicine, “Sapienza” University, Via di Grottarossa 1035-1039, Rome, 00189, Italy, Tel +39 06 3377-5949, Email [email protected]: “Cast nephropathy” (CN) is a pathological feature of myeloma kidney, also seen to a lesser extent in the context of severe nephrotic syndrome from non-haematological diseases. The name relates to obstruction of distal tubules by “casts” of luminal proteins concentrated by intensive water reabsorption resulting from dehydration or high-dose diuretics. Filtered proteins form complexes with endogenous tubular Tamm-Horsfall glycoprotein. The resulting gel further slows or stops luminal flow upon complete obstruction of distal convoluted tubules and collecting ducts. Thus, a tubular obstructive form of acute kidney injury (AKI) is a common consequence of CN. The pathogenesis of CN will be reviewed in light of recent advances in the understanding of monoclonal disorders of B lymphocytes, leading to the release of immunoglobulin components (free light chains, FLC) into the bloodstream and their filtration across the glomerular basement membrane. Treatment aiming at reduction of the circulating burden of FLC may help recovery of renal function in a fraction of these patients, besides filling the void between the onset of AKI, histopathological diagnosis, and full response to pharmacologic treatment.Keywords: light chain cast nephropathy, monoclonal gammopathies, multiple myeloma, immunoglobulins, hemodialysis, HFR-SUPRA
