PMC7737524_01
Kidney biopsy: Histological findings in renal biopsy specimens. A: Microscopic features (hematoxylin and eosin staining, x 400): glomeruli show moderate mesangial proliferative lesions, and neutrophils and mononuclear cells are accumulated in the capillary loops. B: Staining of isolated C3 deposition along the glomerular capillaries and mesangium. C: Electron microscopy: the basement membrane shows thickening with dense deposits (arrows).
CNCS-8-096-01.jpg
PMC7737524_01_CNCS-8-096-01.jpg
Figure1
Kidney biopsy revealed diffuse endocapillary and mesangioproliferative glomerulonephritis, glomeruli showed moderate mesangial proliferative lesions, and neutrophils and mononuclear cells were accumulated in capillary loops, which were irregularly thickened (Figure 1A). Immunofluorescence showed strong staining of isolated C3 with deposition along the glomerular capillaries and mesangium (Figure 1B). Electron microscopy revealed electron-dense deposits along the glomerular basement membrane (Figure 1C).
PMC7737524_02
Clinical course and medication of the patient. PSL = prednisolone; MMF = mycophenolate mofetil; ECZ = eculizumab; MP = methylprednisolone pulses; ACEI = angiotensin-converting enzyme inhibitor; ARB = angiotensin II receptor blocker; Cr = creatinine; UP/Cr = urinary protein/creatinine ratio.
CNCS-8-096-02.jpg
PMC7737524_02_CNCS-8-096-02.jpg
Figure2
Following anti-Neisseria meningitis immunization, ECZ treatment was initiated at 900 mg/week for 4 weeks, and then the same dose was administered every 2 weeks until week 49 (Figure 2). Three days after the first ECZ infusion, the serum creatinine level began to decrease (from 0.96 to 0.78 mg/dL), and the kidney function completely normalized within 7 weeks (Figure 2). Immediately before the 10th ECZ infusion, the sC5b-9 level was within the normal level (597.7 ng/mL) (Figure 2). In the long term, PE resolved, and proteinuria decreased from 12.9 to 2.5 g/g creatinine within 1 month (Figure 2).