Table 3.

Current criteria for DKD diagnosis Replica table of the 5 stages of DKD as originally depicted by Tervaert et al. [262].

Class	Description	Inclusion criteria
I	Mild or nonspecific light microscopy changes and electron-microscope proven GBM thickening	Biopsy does not meet any of the criteria mentioned for class II, III or IV GBM > 395 nm in female and > 430 in male individuals 9 years of age or older
IIa	Mild mesangial expansion	Biopsy does not meet criteria for class III or IV
IIb	Severe mesangial expansion	Biopsy does not meet criteria for class III or IV
III	Nodular sclerosis (Kimmelstiel-Wilson lesion)	Biopsy does not meet criteria for class III or IVAt least one convincing Kimmelstiel-Wilson lesion
IV	Advanced diabetic glomerulosclerosis	Global glomerular sclerosis in > 50% glomeruliLesions from class I to III