Glomerular Collapse in Association with Acute Cortical Necrosis in Native Kidneys: All that Collapses is not Idiopathic Collapsing Glomerulopathy

Abstract

Glomerular collapse is an essential characteristic of collapsing glomerulopathy (CG), a distinctive proliferative renal parenchymal disease defined by the segmental or global collapse of capillary tufts associated with prominent podocyte hyperplasia and hypertrophy. First described in the mid-1980s as an idiopathic disorder or following human immunodeficiency virus(HIV)-1 infection, it is now associated with a broad range of diseases and different pathogenetic pathways which contribute to the podocyte injury and their aberrant proliferation. Although the association between subtotal infarction and <em>de novo</em> CG in transplanted kidneys has recently been reported, to our knowledge, no such association of this lesion with the acute cortical necrosis (ACN) in the native kidneys has been reported in literature to date. We describe 2 cases of glomerular collapse with typical morphological features of CG occurring in the background of ACN in native kidneys and discuss its possible pathogenesis with reference to the existing literature

Collapsing focal segmental glomerulosclerosis: Increasing the awareness

“…Almost all reported studies have shown that its clinicopathological profile is more severe and renal survival markedly reduced in comparison with ncFSGS (6)(7)(8)12). Most important of all, the list of etiologic agents/associated conditions is continuously expanding (13)(14)(15)(16). Although numerous advances have been made in understanding and unraveling the pathomechanisms of this disease, but the picture is still far from clear (2, 3).…”

“…Rather, its detection on renal biopsy specimens should lead to a search for the growing list of etiological factors, before it can be labeled as idiopathic form of the disease (5). It is noteworthy that among the growing list of possible etiologies, ischemia has emerged as the number one cause, not only in the native, but also the transplanted kidneys (13,(20)(21)(22)(23). The ischemia may be of vasculopathic or hypovolemic in origin.…”

“…The ischemia may be of vasculopathic or hypovolemic in origin. We have recently described a number of cases of cFSGS in association with patchy acute cortical necrosis of hemodynamic origin with no evidence of vasculopathy (13,14). The case reported by Mohammadi Torbati has history of hypertension of 3-year duration, but there is no mention of the vascular changes on the renal biopsy.…”

“…Rather, it represents a dramatic response pattern of renal parenchyma in genetically conditioned patients to a wide variety of injurious agents. This has led to a reclassification of this lesion into three categories: idiopathic or primary, reactive or secondary, and genetic forms (10)(11)(12)(13)(14). It also implies that the course of the disease and the ultimate outcome will largely depend on the underlying cause (13,14).…”

“…This has led to a reclassification of this lesion into three categories: idiopathic or primary, reactive or secondary, and genetic forms (10)(11)(12)(13)(14). It also implies that the course of the disease and the ultimate outcome will largely depend on the underlying cause (13,14). Moreover, although, the disease is defined by the glomerular lesions, it is the extent and severity of acute and chronic changes in the tubulointerstitial compartment, which determines the prognosis of the condition (10).…”