case_images: PMC10622965_01
case_images: Renal ultrasound findings. Sagittal view of the right kidney showing a normal-sized kidney with swollen parenchyma measuring 26 mm (ref. range: 13-18 mm).
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case_images: PMC10622965_01_fmed-10-1279005-g0001.jpg
case_images: F1
case_images: An ultrasound of the kidneys illustrated normal-sized kidneys with a swollen parenchyma and no evidence of obstructive nephropathy (Figure 1).
case_images: Photomicrographs of the pathological findings in renal biopsy. (A) Light microscopy with hematoxylin and eosin staining 5x. Diffuse dense interstitial infiltration with small lymphocyte-like cells in diffuse pattern. (B) Magnification depicting normal glomeruli and tubular atrophy and fibrosis alongside infiltrates (HE staining 10x). (C, D) Immunocytochemistry. CD20 and CD23 staining proving the presence of lymphoid B cells.
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case_images: F2
case_images: Light microscopy showed dense infiltration of the cortical interstitium and capsule by mature monomorphic small lymphocytes (Figures 2A, B). Immunocytochemical staining revealed that the infiltrate consisted mainly of monoclonal B lymphoid cells, which tested positive for CD20 and CD23 (Figures 2C, D).