Evolution of human kidney allograft pathology diagnostics through 30 years of the Banff classification process

Table 1 Adequacy criteria of renal allograft biopsies for an accurate pathologic diagnosis

Parameters/investigations	Requirements
Number of cores	Two (these should be divided to procure tissue for IF and EM studies, if necessary)
Components of graft parenchyma	Both cortex and medulla
For the light microscopic study	A significant amount of cortex containing up to: (1) 10 glomeruli; and (2) 2 arteries
For the immunofluorescence study	Cortex with up to 3 glomeruli
For the electron microscopic study	Cortex with 1 glomerulus

EM: Electron microscopy; IF: Immunofluorescence.