case_images: PMC8531272_01
case_images: Light, immunofluorescence, electron, and immune-electron microscopy findings in Case 1. (A) Immunofluorescence studies revealed bright lambda staining in the segmental mesangial area and along capillary walls (x400). (B) Light microscopy showed a mesangial proliferative pattern of injury (periodic acid-silver methenamine + Masson trichrome staining, x400). (C) Electron microscopy revealed electron-dense deposits in segmental mesangial and subendothelial regions (x800). (D) Immunoelectron microscopy demonstrated lambda deposition in the mesangial area and segmental subendothelial regions (x8,000).
case_images: fmed-08-706971-g0001.jpg
case_images: PMC8531272_01_fmed-08-706971-g0001.jpg
case_images: F1
case_images: Electron microscopy revealed electron-dense deposits in the subendothelial area and along segmental GBM, which were prominent lambda under immunoelectron microscopy (Figures 1A-D).
case_images: Light, immunofluorescence, electron, and immunoelectron microscopy findings in Case 2. (A) Immunofluorescence staining revealed bright kappa deposition in the mesangial area and along capillary walls (x400). (B) Light microscopy revealed a membranoproliferative pattern of injury (periodic acid-silver methenamine + Masson trichrome staining, x400). (C) Electron microscopy demonstrated electron-dense deposits in subendothelial and mesangial regions (x8,000). (D) Immunoelectron microscopy showed kappa deposition in the mesangial area and inner GBM (x8,000).
case_images: fmed-08-706971-g0002.jpg
case_images: PMC8531272_01_fmed-08-706971-g0002.jpg
case_images: F2
case_images: After consulting the hematology physician, his treatment was changed to lenalidomide (25 mg daily, days 1 through 21 of each 28-day cycle) and dexamethasone (20 mg once weekly) (Rd therapy). After eight cycles of Rd therapy, his hematological response achieved partial remission (kappa/lambda ratio 0.28, kappa 35.4 mg/L, lambda 125 mg/L), his nephrotic syndrome achieved partial remission (UTP 2.7 g/d, Alb 35.1 g/L), and impaired renal function was restored (eGFR 77.541 ml/min/1.7 m2) (Figure 2).
case_images: PMC8531272_02
case_images: Clinical course of Case 1. After treatment with lenalidomide, the renal impairment and proteinuria caused by LCDD was improved. BCD: bortezomib (2 mg, once weekly), cyclophosphamide (200 mg, once weekly), and dexamethasone (20 mg, once weekly); Rd: lenalidomide (25 mg daily, on Days 1 through 21 of each 28-day cycle) and dexamethasone (20 mg once weekly).
case_images: fmed-08-706971-g0003.jpg
case_images: PMC8531272_02_fmed-08-706971-g0003.jpg
case_images: F3
case_images: GBM, mesangial area, and endolysosome of renal tubular epithelial cells, which were prominent kappa under immunoelectron microscopy (Figures 3A-D). Given his outstanding anemia, the diagnosis of multiple myeloma was suspected but unproven.
case_images: Clinical course of Case 2. After treatment with lenalidomide, the renal impairment and proteinuria caused by LCDD was aggravting. BCD: bortezomib (2 mg, once weekly), cyclophosphamide (200 mg, once weekly), and dexamethasone (20 mg, once weekly); Rd: lenalidomide (25 mg daily, on Days 1 through 21 of each 28-day cycle) and dexamethasone (20 mg once weekly).
case_images: fmed-08-706971-g0004.jpg
case_images: PMC8531272_02_fmed-08-706971-g0004.jpg
case_images: F4
case_images: After four courses of Rd therapy, his free light chain ratio showed improvement (kappa 1185 mg/L, lambda 42.4 mg/L, kappa/lambda ratio 27.9), but his nephrotic syndrome and anemia both aggregated (UTP 9.07 g/d, Alb 23.1 g/L, and Hgb 49 g/L) with relatively preserved renal function (eGFR 59.911 ml/min/1.73 m2) (Figure 4).