PMC10185008_01
The left panel shows glomeruli with crescents (Jones silver 100x). The right panel shows a glomerulus with mesangial widening and hypercellularity with a thickening of the basement membrane and an overlying cellular crescent (HE 400x)
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The underlying tuft had an uniform MPGN pattern of injury with mesangial and endocapillary hypercellularity and a diffuse thickening and duplication of the basement membrane [Figure 1].
Composite immunofluorescence panel showing strong positivity for IgG, C3, and C1q as prominent mesangial smudgy deposits and around the capillary loops. There is light chain restriction with strong kappa light chains and negative lambda light chains (FITC-labeled antibodies 200x)
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There was kappa light chain restriction [Figure 2].
Electron microscopy showing mesangial electron-dense granular deposits in the subendothelial location (left panel) and mesangial location (middle panel). The right panel shows subendothelial deposits and diffuse foot process effacement (3000x)
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There was diffuse foot process effacement [Figure 3].
The top panel shows two hypercellular glomeruli with an unremarkable tubule-interstitium (PAS 100x). The bottom panel shows the glomerulus with a mesangial hypercellularity and an irregular thickening of the basement membrane with focal double contours (400x)
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There was no evidence of rejection [Figure 4].
Immunofluorescence of the allograft biopsy showing strong staining for IgG, C3c, and C1q with kappa light chain restriction, similar to that seen in the native kidney (FITC- labeled antibodies 200x)
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The direct immunofluorescence study revealed a patten of deposits identical to that in the native kidney with IgGk deposits [Figure 5].
IgG isotype staining showing positivity for IgG3 and negative for IgG1, IgG2 and IgG4.I (FITC-labeled antibodies 200x)
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This time, IgG isotype stains were also done, and the deposits were of the IgG3 subtype [Figure 6].