Hematuria and Proteinuria in a Patient with Monoclonal Gammopathy of Renal Significance

A 72-year-old male presented with bilateral lower limb edema and fatigue accompanied by hypertension (150/80 mm Hg).Laboratory investigations revealed significant proteinuria of 3.4 g/gCr, hematuria (red blood cells 40.0/ml, 70% dysmorphic), serum creatinine of 1.1 mg/dl, and eGFR of 62.4 ml/min per 1.73 m 2 .Further quantification demonstrated 24-hour urine protein excretion of 4.3 g/day with severe hypoalbuminemia (serum albumin 2.1 g/dl).Serum and urine protein electrophoresis/ immunofixation identified IgGk-type monoclonal protein.Free light chain k was 70.5 mg/L, and free light chain l was 43.7 mg/L.Tests for hepatitis B and C viruses, antinuclear antibodies, antineutrophil cytoplasmic antibodies, and double-stranded DNA antibodies were negative.Cryoglobulin and malignancy screenings were all negative.