The Columbia classification of focal segmental glomerulosclerosis (FSGS) describes 5 variants, of which the cellular variant is the rarest. This variant is more common in children than in adults, and typically presents with nephrotic-range proteinuria. The cellular variant can be diagnosed after excluding collapsing and tip variants, when there is endocapillary hypercellularity involving at least 25% of the tuft of at least one glomerulus, without immune complexes, and typically with extensive foot process effacement.

Glomerulonephritis with dominant C3, a form of C3 glomerulopathy, typically presents with subnephrotic proteinuria and hematuria. Although a minority of patients may present with nephrotic syndrome, about half present with hypertension and impaired glomerular filtration rate. Up to 15% progress to end-stage renal disease. C3 glomerulopathy is rare with a typical age of onset of 30 years (range, 7-70 years).

Antibiotic therapy has decreased the incidence of glomerulonephritis related to subacute bacterial endocarditis (SBE). Kidney involvement may be the initial manifestation of SBE in about 20% of patients. Hematuria and mild proteinuria are commonly present. Hypertension and nephrotic syndrome are rare. Serum complement levels may be low. Gross hematuria may be present in patients with renal infarctions related to embolic events. The degree of GFR loss correlates with the severity of glomerulonephritis; diffuse glomerulonephritis causes moderate GFR loss, and necrotizing glomerulonephritis with crescents can cause a rapid GFR decline.

Antibiotic therapy has decreased the incidence of glomerulonephritis related to subacute bacterial endocarditis (SBE). Kidney involvement may be the initial manifestation of SBE in about 20% of patients. Hematuria and mild proteinuria are commonly present. Hypertension and nephrotic syndrome are rare. Serum complement levels may be low. Gross hematuria may be present in patients with renal infarctions related to embolic events. The degree of GFR loss correlates with the severity of glomerulonephritis; diffuse glomerulonephritis causes moderate GFR loss, and necrotizing glomerulonephritis with crescents can cause a rapid GFR decline.

Chronic antibody-mediated rejection is commonly associated with progressive loss of kidney function and proteinuria, although early stages may be subclinical and recognizable only through protocol biopsies.