Special stains can distinguish hepatic necrosis with regenerative nodules from cirrhosis.

Background: Focal zones of hepatic necrosis alternating with nodular regeneration in severe, acute to subacute hepatitis can be difficult to differentiate histologically from established cirrhosis, and diagnostic errors can result in incorrect patient management. Thus, an easily applicable, well-defined histologic method for differentiating these two lesions would be useful.

Methods: We examined trichrome (TRI), reticulin (RETIC), Verhoeff's elastic (VE), and orcein (ORC) stains on 13 cases of hepatic necrosis with regenerative nodules and 10 cases of end-stage cirrhosis to evaluate their utility for this problem.

Muconephrosis.

We report a case of a mucus-filled kidney (muconephrosis) encountered during laparoscopic nephrectomy for presumed xanthogranulomatous pyelonephritis. Conversion to open nephrectomy and en-bloc right hemicolectomy were necessary because of severe perinephric fibrosis and suspected renal-enteral fistula. Pathologic examination revealed a renal pelvic villous adenoma and diffuse intestinal metaplasia of the urothelium; no enteral communication or gastrointestinal pathologic features were found.