Table 5.

Guidelines for LM

Glomeruli

No. of glomeruli, including no. of globally and segmentally sclerosed and ischemic glomeruli

Focal versus diffuse and segmental versus global findings

Hypercellularity: mesangial, endocapillary, or exudative

Crescents: no./percentage, type (cellular, fibrocellular, or fibrous), and size (segmental or circumferential)

Fibrinoid necrosis and karyorrhexis

Wire loops, pseudo-(hyaline) microthrombi, and fibrin thrombi

Mesangial matrix expansion and presence of mesangiolysis

GBM thickening/thinning, double-contour formation, and other GBM abnormalities (e.g., spikes)

Disruption of GBM

Disruption of Bowman’s capsule

Tubules and interstitium

Interstitial inflammation: type of infiltrate and location

Casts, crystals, and cysts

Acute tubular injury

Tubular basement abnormalities

IFTA: absent, mild, moderate, or severe

Vessels

Arteritis, emboli, and thrombosis

Arteriosclerosis and arteriolosclerosis: absent, mild, moderate, or severe