Fingerprint pattern in mixed cryoglobulinemia

High-power electron micrograph of a cryoprecipitate in the mesangium, showing the characteristic substructure which often has a "fingerprint" appearance (arrows).

Electron micrograph of a normal glomerular capillary loop showing the fenestrated endothelial cell (Endo), the glomerular basement membrane (GBM), and the epithelial cells with its interdigitating foot processes (arrow). The GBM is thin, and no electron-dense deposits are present. Two normal platelets are seen in the capillary lumen.