Neutrophil gelatinase-associated lipocalin as a biomarker of renal impairment in patients with multiple myeloma.

BACKGROUND

Renal impairment (RI) is a common complication of multiple myeloma (MM) and is associated with an unfavorable prognosis. Several new markers of kidney damage have been introduced in recent years. The aim of this study was to assess whether neutrophil gelatinase-associated lipocalin (NGAL) can be used as a biomarker of RI in patients with MM.

PATIENTS AND METHODS

A total of 199 samples from patients with MM were studied. Plasma NGAL, serum creatinine (sCr), cystatin C (Cys-C), serum free light chain (sFLC), and myeloma protein (M protein) concentrations were measured, and estimated glomerular filtration rate (eGFR) was calculated using the Modification of Diet in Renal Disease formula.

RESULTS

Plasma NGAL levels significantly correlated with the degree of RI as defined by the Kidney Disease Improving Global Outcomes chronic kidney disease stage and with sCr and Cys-C concentrations and eGFR. Moreover, the plasma NGAL level was predictive of the myeloma burden and showed a significant correlation with sFLC, dFLC (difference between involved and uninvolved FLC), and M-protein concentrations.

CONCLUSION

Plasma NGAL is not only a sensitive biomarker of renal function but may also be a useful marker that reflects tumor burden in patients with MM.