Figure 1.

Kidney biopsy: representative light microscopy shows global collapse of the glomerular capillary loops accompanied by hyperplasia and hypertrophy of overlying glomerular epithelial cells (a–c) many of which contain scattered eosinophilic protein droplets (a, arrow) and numerous intracytoplasmic vacuoles (b, arrows). a: Jones methenamine silver stain; b: H&E stain; c: Masson's trichrome stain, ×400. Acute tubular injury is manifest in many cortical tubules, accompanied by interstitial edema and patchy interstitial mononuclear inflammatory infiltrates (d: H&E stain, ×400).