case_images: PMC10505429_01
case_images: Kidney histology. (A) First kidney biopsy (at diagnosis). (a) Light microscopy. Lobulated glomerulus with global thickening of the glomerular membranes due to double contours and endocapillary hypercellularity suggestive of membranoproliferative nephritis (TRM 40x). (b) Immunofluorescence. Bright granular C3 staining along capillary walls and within mesangial areas. (c) Electron Microscopy. Granular powdery electron-dense deposits along the subendothelial space (indicative of a diagnosis of C3 glomerulonephritis). (B) Third kidney biopsy (2 months after hemodialysis discontinuation). (a) Light microscopy. Glomeruli showed more prominent nodular mesangial matrix expansion than the two previous biopsies but still with lobulation due to hypercellularity, endocapillary proliferation, and double contours (PAS 20X). (b) Immunofluorescence. Diffuse granular C3 staining along capillary walls and within mesangial areas. (c) Electron Microscopy. Finely granular powdery electron-dense deposits along the subendothelial space.
case_images: fmed-10-1266172-g001.jpg
case_images: PMC10505429_01_fmed-10-1266172-g001.jpg
case_images: fig1
case_images: Electron microscopy confirmed the presence of subendothelial electron-dense deposits, indicative of a diagnosis of C3GN (Figure 1A). On February 2023, while the patient's renal function was stable and the monoclonal component reduced to 1.1 from 3.5 g/L, a third kidney biopsy was performed (Figure 1B).
case_images: Clinical course, timeline of histological exams and response to the treatments of the index case. kidney biopsy (KB), bone marrow biopsy (BM), cyclophosphamide (Cyc), prednisone (P), bortezomib/cyclophosphamide/dexamethasone (CyBorD), hemodialysis (HD), daratumumab-lenalidomide-dexamethasone (D-RD).
case_images: fmed-10-1266172-g002.jpg
case_images: PMC10505429_01_fmed-10-1266172-g002.jpg
case_images: fig2
case_images: The patient continued maintenance therapy with monthly administration of daratumumab as a single agent (Figure 2).