Viral cytopathic changes consist of smudgy basophilic intranuclear inclusions with enlarged nuclei of infected cells. Distal tubules are more commonly involved than proximal tubules. There is associated acute tubular injury, often with frank tubular necrosis and destruction, with acute interstitial nephritis, often with a pleomorphic infiltrate composed of lymphocytes, histiocytes, plasma cells, and variable numbers of neutrophils, with interstitial edema and hemorrhage. Tubular destruction may be associated with necrotizing interstitial granulomas. Severe granulomatous tubulointerstitial nephritis appears to be characteristic of adenoviral infection and is quite rare in other viral infections. Focal wedge-shaped necrosis may occur in renal parenchyma. Immunostaining for adenovirus shows strong nuclear and cytoplasmic staining in infected cells. [from
HPO]