collapsing glomerulopathy

Collapsing glomerulopathy (CG) is an aggressive variant of focal segmental glomerular sclerosis. It is a renal disease with severe proteinuria and rapidly progressive renal failure. The pathogenesis of CG is unknown. It can occur in native kidneys or de novo in renal allografts

Collapsing glomerulopathy (CG) strongly resembles human immunodeficiency virus (HIV)-associated nephropathy, but the patients are HIV negative.

Collapsing glomerulopathy is defined by collapse and retraction of glomerular tuft, segmental (involving part of the tuft) or global (involving all of the tuft), with proliferation of overlying podocytes. It has a worse prognosis than usual FSGS.

Collapsing glomerulopathy (CG) represents a morphologic pattern of disease, characterized histologically by glomerular capillary collapse, severe podocyte injury, and glomerular epithelial cell proliferation, and clinically by marked proteinuria and renal insufficiency.

Synopsis

 glomerular lesions

• capillary loop collapse
• prominent podocytes filling Bowman space

 severe tubulointerstitial injury

• tubular epithelial degenerative changes
• microcystic dilation of tubules
• renal interstitial inflammatory cell infiltrate

 associated obliterative vascular changes

• chronic obliterative transplant arteriopathy
• acute vascular rejection
• thrombotic microangiopathy

Etiology

CG has multiple etiologies; however, many questions remain about its pathogenesis.

 idopathic collapsing glomerulopathy
 HIV-associated collapsing glomerulopathy

• reticular aggregates by EM

Animal models

An animal model of CG, is characterized by absence of the normal podocyte cytoskeletal protein alpha-actinin-4. (18185509)

See also

 renal transplants (renal allografts)
 rena biopsy
 proteinuria

References

 Albaqumi M, Barisoni L. Current views on collapsing glomerulopathy. J Am Soc
Nephrol. 2008 Jul;19(7):1276-81. PMID: 18287560

 Nadasdy T, Allen C, Zand MS. Zonal distribution of glomerular collapse in renal allografts: possible role of vascular changes. Hum Pathol. 2002 Apr;33(4):437-41. PMID: 12055680