Obliterative portal venopathy: A neglected and probably misdiagnosed disease with peculiar etiology in South America

Shared Features of Obliterative Portal Venopathy, Normal Liver, and Chronic Liver Disease: A Histologic and Morphometric Analysis

Obliterative portal venopathy (OPV) is a cause of noncirrhotic portal hypertension, and its diagnosis is challenging, as the features are heterogeneous, subtle, and may be mistaken as "normal." We sought to compare OPV cases (n = 72; 326 total portal tracts [PT]) with 2 control groups: control group 1 comprised of normal liver (n = 40; 192 PTs) and control group 2 comprised of liver biopsies with chronic liver disease with OPV features (n = 40; 200 PTs). Morphometry was applied to determine the overall PT area and the luminal area of dystrophic portal veins (PVs). The frequency of absent native PVs was determined. Using trichrome-stained slides, approximately 5 PTs were randomly selected for morphometry utilizing Philips IntelliSite Pathology Solution 3.3. Clinical data were extracted from electronic health records. Of the 326 PTs in the OPV cases, phlebosclerosis was found in 31.6%, densely fibrotic PTs in 12.7%, dystrophic PVs in 31.4%, and absent native PVs in 44.5%. When comparing the OPV group with control group 1, dystrophic PVs, absent native PVs, phlebosclerosis, fibrotic PTs, greater luminal area of dystrophic PV, and a higher ratio of dystrophic PV area to PT area were more frequently found in the OPV group. No significant difference in overall PT area was found. When comparing control group 2 with OPV cases, densely fibrotic PTs were more frequent when compared with OPV cases. This study shows that absent native PVs are the most frequent feature in OPV. Other features that are less frequent but still significantly different from normal liver include dystrophic PVs, greater luminal area of dystrophic PVs, phlebosclerosis, and PT fibrosis. Except for densely fibrotic PTs in control group 2, all other features showed similar frequency as OPV. Pathologists should be aware that OPV features may be present in liver biopsies from both normal and chronic liver diseases.

Non-cirrhotic portal fibrosis/idiopathic portal hypertension: APASL recommendations for diagnosis and management

Since the Asian Pacific Association for the Study of the Liver (APASL) published guidelines on non-cirrhotic portal fibrosis/idiopathic portal hypertension in 2007, there has been a surge in new information, especially with the introduction of the term porto-sinusoidal vascular disorder (PSVD). Non-cirrhotic intra-hepatic causes of portal hypertension include disorders with a clearly identifiable etiology, such as schistosomiasis, as well as disorders with an unclear etiology such as non-cirrhotic portal fibrosis (NCPF), also termed idiopathic portal hypertension (IPH). This entity is being increasingly recognized as being associated with systemic disease and drug therapy, especially cancer therapy. An international working group with extensive expertise in portal hypertension was assigned with formulating consensus guidelines to clarify the definition, diagnosis, histological features, natural history, and management of NCPF/IPH, especially in the context of PSVD. The guidelines were prepared based on evidence from existing published literature. Whenever there was paucity of evidence, expert opinion was included after detailed deliberation. The goal of this manuscript, therefore, is to enhance the current understanding and help create global consensus on the issues surrounding NCPF/IPH.