Figure 2

Definition of glomerular tip and types of glomerular tip lesions. The glomerular tip is defined as the outer 25% of the tuft next to the origin of the proximal tubule, based on the Columbia Classification. Glomerular tip prolapse means that some component of the glomerulus, such as the basement membrane or the mesangial cells, is prolapsing into the proximal tubules. Glomerular tip adhesion is defined as a continuity of the extracellular matrix between the glomerular tuft and Bowman’s capsule in the tip domain. Glomerular tip sclerosis is defined as segmental sclerosis in a portion of the glomerular tip. Glomerular tip foam cells refer to the presence of foam cells in a portion of the glomerular tip.