case_images: PMC10876091_01
case_images: Renal biopsy. Left column, light microscopy: (A) glomerulus showing mild thickenning of the capillary walls and mesangial hypercelularity (Periodic Acid-Schiff Stain 400x), (B) normal tubulointerstitial compartment (Periodic Acid-Schiff Stain 200x), (C) normal medium size artery (Masson s trichromic stain 200x). Right column, glomerular inmune deposits in (D) mesangial (white arrows), (E) subepithelial (blue arrows), and (F) subendothelial (red arrows) localization.
case_images: fneph-04-1343594-g001.jpg
case_images: PMC10876091_01_fneph-04-1343594-g001.jpg
case_images: f1
case_images: A pure nephrotic syndrome was diagnosed, antibodies to the phospholipase A2 receptor (PLA2R) resulted negative and a renal biopsy was performed revealing 1 out of 4 globally sclerotic glomeruli with thickened membranes, mesangial proliferation, protein reabsorption drops in tubules, scant lymphocytic infiltrate, tubular atrophy, and discrete interstitial fibrosis ( Figure 1 ). Electron microscopy confirmed the existence of significant, continuous subepithelial, mesangial and subendothelial electrodense deposits also ( Figure 1 ), which were associated with an increase in mesangial matrix and cells.
case_images: Direct immunofluorescence in frozen renal tissue showing a "full house" pattern.
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case_images: PMC10876091_01_fneph-04-1343594-g002.jpg
case_images: f2
case_images: Immunofluorescence demonstrated a full-house pattern positivity for IgG, IgM, IgA, C3, C1q, fibrinogen, kappa, and lambda light chains, in addition to an IgG weak antinuclear antibody-type extraglomerular reaction ( Figure 2 ).
case_images: Clinical evolution: (A) platelets and hemoglobin, (B) LDH and creatinine in relationship with therapeutical interventions. PDN, prednisone; HCQ, hydroxychloroquine; AZA, azathioprine; MMF, mycophenolate mophetil; PLEX, plasma exchange (number of sesiones); RTX, rituximab; CFM, cyclophosphamide iv pulses.
case_images: fneph-04-1343594-g003.jpg
case_images: PMC10876091_01_fneph-04-1343594-g003.jpg
case_images: f3
case_images: Therefore, the treatment was altered to include intravenous cyclophosphamide (three doses of one gram), resulting in complete hematological remission, normalization of anemia, stable platelet counts, and a return to normal ADAMST13 activity (200%) with disappearance of the inhibitor; however, dialysis-dependent renal failure remained persistent ( Figure 3 ).