The continual presence of C3d but not IgG glomerular capillary deposition in stage I idiopathic membranous nephropathy in patients receiving corticosteroid treatment.
BACKGROUND
Pathologic diagnosis of stage I idiopathic membranous nephropathy (MN-I) requires electron microscopy or immunohistochemistry that shows a glomerular capillary staining pattern of IgG and C3. However, it is not uncommon that renal biopsy did not obtain sufficient material for electron microscopy and that IgG and C3 staining in glomeruli largely lost at biopsy due to corticosteroid treatment. Since C3d is one of the final degradation products of C3 that is more stable in vivo, we determine if C3d staining could be used as a novel immunohistochemical marker for MN-I.


RESULTS
74 MN-I patients with electron microscopy proven MN-I were examined by immunoperoxidase staining of C3d. Intensive C3d staining was present in glomerular capillary like the staining pattern of IgG and C3 in MN-I. Importantly, in 40 MN-I patients who underwent corticosteroid treatment at biopsy the intensity and glomerular capillary pattern of C3d staining remained largely intact while the staining for IgG had substantially reduced and the pattern of glomerular capillary staining became unrecognizable.


CONCLUSIONS
C3d glomerular capillary staining may be a novel marker for pathologic diagnosis of MN-I that is continuously present at biopsy in patient who has received corticosteroid treatment.
The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2120780075734479.
Department of Pathology, Dongfang Hospital, Fujian Medical University, Fuzhou 350025, China.
Rui
R
Zhang
Zhi-yong
ZY
Zheng
Jian-song
JS
Lin
Li-juan
LJ
Qu
Feng
F
Zheng
D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use*; D000328:Adult; D015415:Biomarkers / Q000032:analysis; D001706:Biopsy; D002196:Capillaries / Q000187:drug effects* / Q000276:immunology / Q000648:ultrastructure; D016009:Chi-Square Distribution; D002648:Child; D015933:Complement C3d / Q000032:analysis*; D005260:Female; D015433:Glomerulonephritis, Membranous / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D007150:Immunohistochemistry; D007678:Kidney Glomerulus / Q000098:blood supply / Q000187:drug effects* / Q000276:immunology / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D011237:Predictive Value of Tests; D016896:Treatment Outcome; D055815:Young Adult
D000305:Adrenal Cortex Hormones; D015415:Biomarkers; D007074:Immunoglobulin G; D015933:Complement C3d