title: Renal involvement of thrombotic thrombocytopenic purpura: special reference to the glomeruloid structures.
abstract: We report the case of a 9-year-old girl with biopsy-proven renal thrombotic microangiopathy in thrombotic thrombocytopenic purpura (TTP), with particular reference to the glomeruloid structures. The renal biopsy sample from this TTP patient revealed platelet thrombus deposition, a glomeruloid structure and aneurysm with relative sparing of the glomeruli. The glomeruloid structure displayed a proliferation of mainly capillary-sized channels lined by Factor VIII-related, antigen-positive plump endothelial cells embedded in the edematous connective tissue. These glomeruloid vessels communicated with the aneurysmal segment at the end portion of the arteriolar branch. We believe that the glomeruloid structures in TTP represent not merely organization or recanalization of thrombus but rather active angiogenesis through aneurysmal dilation in the arteriolized vessel, probably initiated by platelet agglutination.
authors.affiliation: Department of Pathology, Shinshu University School of Medicine, Matsumoto, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Katoh
authors.forename: H
authors.initials: H
authors.lastname: Shigematsu
mesh_terms: D000783:Aneurysm / Q000378:metabolism / Q000473:pathology; D001707:Biopsy, Needle; D001792:Blood Platelets / Q000378:metabolism / Q000473:pathology; D002648:Child; D004730:Endothelium, Vascular / Q000378:metabolism / Q000473:pathology; D005169:Factor VIII / Q000276:immunology / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007674:Kidney Diseases / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D007678:Kidney Glomerulus / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000473:pathology; D010956:Plasmapheresis; D010974:Platelet Aggregation; D011697:Purpura, Thrombotic Thrombocytopenic / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D013927:Thrombosis / Q000378:metabolism / Q000473:pathology; D014841:von Willebrand Factor / Q000276:immunology / Q000378:metabolism
chemical_list: D014841:von Willebrand Factor; D005169:Factor VIII