case_images: PMC11750788_01
case_images: Images of the patient's renal needle biopsy. (A) The blue arrow shows glomerulosclerosis, with 8 out of 15 glomeruli showing sclerosis, and no segmental glomerulosclerosis (HE). (B) The blue circles show protein casts (PAS). (C) The glomerular basement membrane shows no thickening, with no double-track (PASM). (D) The purple arrow shows the atrophic change in the renal tubules, with approximately 40% of the tubular area showing atrophy (Masson). (E,F) The yellow circles show segmental mesangial matrix insertion into the glomerular basement membrane, forming a double-track structure. The red arrows show vacuolar degeneration of the renal tubular epithelial cells. The red circle shows focal infiltration of inflammatory cells in the renal interstitium. The foot processes exhibit segmental fusion changes. Both mesangial cells and the matrix show mild proliferation (EM).
case_images: fmed-11-1525062-g001.jpg
case_images: PMC11750788_01_fmed-11-1525062-g001.jpg
case_images: fig1
case_images: Renal biopsy revealed mild mesangial proliferative glomerulopathy with partial glomerulosclerosis (8/15) and moderate (40%) chronic tubulointerstitial injury (Figure 1).
case_images: Sequencing of the mutation in the ADAMTS13 gene and intron +- exon and domain structures of ADAMTS13. (A) The patient, along with his father and sister, carried the heterozygous variant c.1335delC (p. Phe445LeufsTer52). (B) The patient and his mother carried the heterozygous variant c.1045C > T (p.Arg349Cys). The red arrows indicate the base change in the DNA. (C) DAMTS13 is a metalloprotease that consists of a signal peptide domain (S), a pro-peptide domain (P), a metalloprotease domain (MP), a disintegrin domain (DIS), a series of thrombospondin type 1 (TSP 1), a cysteine-rich domain (CYS), and a spacer domain (Spacer). Additionally, the C-tail consists of seven more repeats of thrombospondin type 1 (TSP 2-8) and CUB domains (CUB1-2). The red arrows indicate the locations of the variants in the exon.
case_images: fmed-11-1525062-g002.jpg
case_images: PMC11750788_01_fmed-11-1525062-g002.jpg
case_images: fig2
case_images: Moreover, the family investigation revealed that the patient's parents and sister also carried heterozygous ADAMTS13 mutation (Figure 2), but had normal ADAMTS13 activities (Table 1) and were in good health.
case_images: Timeline of the case. CS, corticosteroid; Ig, gamma globulin; FFP, fresh frozen plasma.
case_images: fmed-11-1525062-g003.jpg
case_images: PMC11750788_01_fmed-11-1525062-g003.jpg
case_images: fig3
case_images: The timeline of this case is shown in Figure 3.