Editorial
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World J Gastroenterol. Mar 21, 2011; 17(11): 1400-1409
Published online Mar 21, 2011. doi: 10.3748/wjg.v17.i11.1400
Nodular regenerative hyperplasia: Evolving concepts on underdiagnosed cause of portal hypertension
Marek Hartleb, Krzysztof Gutkowski, Piotr Milkiewicz
Marek Hartleb, Krzysztof Gutkowski, Department of Gastroenterology and Hepatology, Medical University of Silesia, 40-752 Katowice, Poland
Piotr Milkiewicz, Liver Unit, Pomeranian Medical University, 70-111 Szczecin, Poland
Author contributions: Hartleb M designed and wrote the review; Gutkowski K wrote the references, table and figure; Milkiewicz P revised the paper.
Correspondence to: Marek Hartleb, Professor of Medicine, Head of the Department of Gastroenterology and Hepatology, Silesian University of Medicine, ul. Medyków 14, 40-752 Katowice, Poland. mhartleb@sum.edu.pl
Telephone: +48-32-7894401 Fax: +48-32-7894402
Received: October 7, 2010
Revised: December 22, 2010
Accepted: December 29, 2010
Published online: March 21, 2011
Abstract

Nodular regenerative hyperplasia (NRH) is a rare liver condition characterized by a widespread benign transformation of the hepatic parenchyma into small regenerative nodules. NRH may lead to the development of non-cirrhotic portal hypertension. There are no published systematic population studies on NRH and our current knowledge is limited to case reports and case series. NRH may develop via autoimmune, hematological, infectious, neoplastic, or drug-related causes. The disease is usually asymptomatic, slowly or non-progressive unless complications of portal hypertension develop. Accurate diagnosis is made by histopathology, which demonstrates diffuse micronodular transformation without fibrous septa. Lack of perinuclear collagen tissue distinguishes NRH from typical regenerative nodules in the cirrhotic liver. While the initial treatment is to address the underlying disease, ultimately the therapy is directed to the management of portal hypertension. The prognosis of NRH depends on both the severity of the underlying illness and the prevention of secondary complications of portal hypertension. In this review we detail the epidemiology, pathogenesis, diagnosis, management, and prognosis of NRH.

Keywords: Nodular regenerative hyperplasia; Portal hypertension; Comorbidities