Membranous glomerulonephritis with crescents.
OBJECTIVE
The coexistence of membranous glomerulonephritis (MGN) and necrotizing and crescentic glomerulonephritis (NCGN) is an unusual finding in a renal biopsy except in lupus nephritis. Little is known about whether these lesions are causally related in any clinical setting.


METHODS
We reviewed the pathology, presentation, and clinical course of 13 non-lupus patients with combined MGN and NCGN in native kidney biopsies (nine females, four males; median age 69 years), with particular attention to evidence of secondary MGN. Additional IgG subclass and phospholipase A2 receptor (PLA2R) immunofluorescence studies were conducted in seven cases.


RESULTS
Eight biopsies were pauci-immune other than the capillary wall deposits of MGN; one patient had a non-lupus immune complex disease, and four had mesangial deposits, including one with rare subendothelial deposits. None had anti-glomerular basement membrane disease. IgG4 was dominant or codominant in the capillary wall deposits in three cases and virtually absent in four; PLA2R was positive in two cases, and negative in five. Seven patients were judged to have secondary MGN, including five of eight ANCA+ patients. Twelve patients were treated with combinations of steroids, cyclophosphamide, rituximab, followed by durable response in seven and relentless progression to end stage renal disease in four.


CONCLUSIONS
Secondary MGN occurs with higher frequency in ANCA-positive NCGN than in the general MGN population. A causal relationship between MGN and NCGN was not established in any patient, but circumstances suggest a common cause in several, including immune complex disease, drug reaction and paraneoplastic syndrome.
Department of Pathology, Oregon Health and Science University, L471, 3181 SW Sam Jackson Park Rd, Portland, OR, 97239, USA.
Caroline M F
CM
Barrett
Megan L
ML
Troxell
Christopher P
CP
Larsen
Donald C
DC
Houghton
D000293:Adolescent; D000368:Aged; D000369:Aged, 80 and over; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000032:analysis; D058846:Antibodies, Monoclonal, Murine-Derived / Q000627:therapeutic use; D002196:Capillaries / Q000737:chemistry; D002648:Child; D003520:Cyclophosphamide / Q000627:therapeutic use; D005260:Female; D015433:Glomerulonephritis, Membranous / Q000150:complications* / Q000188:drug therapy / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007678:Kidney Glomerulus / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D009195:Peroxidase / Q000276:immunology; D054507:Receptors, Phospholipase A2 / Q000032:analysis; D012189:Retrospective Studies; D000069283:Rituximab; D013256:Steroids / Q000627:therapeutic use
D019268:Antibodies, Antineutrophil Cytoplasmic; D058846:Antibodies, Monoclonal, Murine-Derived; D007074:Immunoglobulin G; D007166:Immunosuppressive Agents; D054507:Receptors, Phospholipase A2; D013256:Steroids; D000069283:Rituximab; D003520:Cyclophosphamide; D009195:Peroxidase