Nodular regenerative hyperplasia, portal vein thrombosis, and avascular hip necrosis due to hyperhomocysteinaemia

Metabolome and Microbiota Analysis Reveals the Conducive Effect of Pediococcus acidilactici BCC-1 and Xylan Oligosaccharides on Broiler Chickens

Xylan oligosaccharides (XOS) can promote proliferation of Pediococcus acidilactic BCC-1, which benefits gut health and growth performance of broilers. The study aimed to investigate the effect of Pediococcus acidilactic BCC-1 (referred to BBC) and XOS on the gut metabolome and microbiota of broilers. The feed conversion ratio of BBC group, XOS group and combined XOS and BBC groups was lower than the control group (P < 0.05). Combined XOS and BBC supplementation (MIX group) elevated butyrate content of the cecum (P < 0.05) and improved ileum morphology by enhancing the ratio of the villus to crypt depth (P < 0.05). The 16S rDNA results indicated that both XOS and BBC induced high abundance of butyric acid bacteria. XOS treatment elevated Clostridium XIVa and the BBC group enriched Anaerotruncus and Faecalibacterium. In contrast, MIX group induced higher relative abundance of Clostridiaceae XIVa, Clostridiaceae XIVb and Lachnospiraceae. Besides, MIX group showed lower abundance of pathogenic bacteria such as Campylobacter. Metabolome analysis showed that all the 3 treatment groups (XOS, BBC and MIX) showed lower concentrations of sorbitol and both XOS and BBC group had higher concentrations of pyridoxine levels than CT group. Besides, XOS and BBC groups enhanced the content of hydroxyphenyl derivatives 4-hydroxyphenylpyruvate 1 and 3-(3-hydroxyphenyl) propionic acid, respectively (P < 0.05). Notably, MIX group enhanced both 4-hydroxyphenylpyruvate 1 and 3-(3-hydroxyphenyl) propionic acid (P < 0.05). Thus, XOS and BBC may have a synergistic role to improve the performance of broilers by modulating gut microbiota and metabolome.

What makes non-cirrhotic portal hypertension a common disease in India? Analysis for environmental factors

In India, an unexplained enteropathy is present in a majority of non-cirrhotic intrahepatic portal hypertension (NCIPH) patients. Small intestinal bacterial contamination and tropical enteropathy could trigger inflammatory stimuli and activate the endothelium in the portal venous system. Groundwater contaminated with arsenic is an environmental factor of epidemic proportions in large areas of India which has similar consequences. Von Willebrand factor (a sticky protein) expressed by activated endothelium may promote formation of platelet microthrombi and occlusion of intrahepatic portal vein branches leading to NCIPH. Environmental factors linked to suboptimal hygiene and sanitation, which enter through the gastrointestinal (GI) tract, predispose to platelet plugging onto activated endothelium in portal microcirculation. Thus, NCIPH, an example of poverty linked thrombophilia, is a disease mainly affecting the lower socio-economic strata of Indian population. Public health measures to improve sanitation, provide clean drinking water and eliminate arsenic contamination of drinking water are urgently needed. Till such time as these environmental factors are addressed, NCIPH is likely to remain 'an Indian disease'.

Portal Cavernoma Mimicking Pancreatic Malignancy

Portal cavernoma colangiopathy (PCC) is an uncommon cause of portal hypertension, and it is an important differential diagnosis of pancreatic malignancy given the expanded network of collateral vessels. On imaging studies, portal cavernoma can be seen as a hypoechoic mass, possibly associated with distal common bile duct obstruction. Most cases occur in non-cirrhotic patients. During the symptomatic phase, these patients carry a high-risk of complications related to sustained biliary obstruction. We report a unique patient with obstructive jaundice and a presumed pancreatic mass that proved to be a portal cavernoma complicated by PCC in the setting of nodular regenerative hyperplasia of the liver.

Avascular Necrosis of Femoral Head: A Metabolomic, Biophysical, Biochemical, Electron Microscopic and Histopathological Characterization

Avascular necrosis of the femur head (AVNFH) is a debilitating disease caused due to the use of alcohol, steroids, following trauma or unclear (idiopathic) etiology, affecting mostly the middle aged population. Clinically AVNFH is associated with impaired blood supply to the femoral head resulting in bone necrosis and collapse. Although Homocysteine (HC) has been implicated in AVNFH, levels of homocysteine and its associated pathway metabolites have not been characterized. We demonstrate elevated levels of homocysteine and concomitantly reduced levels of vitamins B6 and B12, in plasma of AVNFH patients. AVNFH patients also had elevated blood levels of sodium and creatinine, and reduced levels of random glucose and haemoglobin. Biophysical and ultrastructural analysis of AVNFH bone revealed increased remodelling and reduced bone mineral density portrayed by increased carbonate to phosphate ratio and decreased Phosphate to amide ratio together with disrupted trabeculae, loss of osteocytes, presence of calcified marrow, and elevated expression of osteocalcin in the osteoblasts localized in necrotic regions. Taken together, our studies for the first time characterize the metabolomic, pathophysiological and morphometric changes associated with AVNFH providing insights for development of new markers and therapeutic strategies for this debilitating disorder.

Nodular regenerative hyperplasia rarely leads to liver transplantation: A 20-year cohort study in all Dutch liver transplant units

BACKGROUND

Nodular regenerative hyperplasia is an uncommon liver condition associated with several autoimmune disorders and drugs. The clinical symptoms of nodular regenerative hyperplasia vary from asymptomatic to severe complications of portal hypertension (nodular regenerative hyperplasia-syndrome).

OBJECTIVE

The purpose of this study was to identify the prognosis and optimal management, as well as the role of liver transplantation, in nodular regenerative hyperplasia.

METHODS

The pathology databases of all three Dutch liver transplant units were retrospectively scrutinised for explanted livers diagnosed with nodular regenerative hyperplasia or without clear diagnosis. Pre- and post-transplantation clinical, biochemical, radiological and histological information was obtained from electronic and paper records.

RESULTS

In total, 1886 patients received a liver transplant. In 255 patients, nodular regenerative hyperplasia could not be excluded. After detailed chart review, the native livers of 11 patients (0.6%) (82% male, median age: 44 years) displayed nodular regenerative hyperplasia. Seven patients (64%) had underlying disorders or drug exposure which possibly caused nodular regenerative hyperplasia. Laboratory and imaging abnormalities were present in all patients but did not contribute to the diagnosis of nodular regenerative hyperplasia. Five-year survival was 73% (median follow-up: four years, range: 2-248 months).

CONCLUSION

Nodular regenerative hyperplasia is a rare finding in patients, predominantly young males, transplanted for end-stage liver disease with unknown aetiology. Nonetheless, liver transplantation may have an important role in end-stage nodular regenerative hyperplasia-syndrome.

Prevalence and clinical significance of nodular regenerative hyperplasia in liver biopsies

BACKGROUND

Nodular regenerative hyperplasia (NRH) is a rare histological disorder associated with a wide variety of systemic diseases.

AIMS

We aimed (i) to report the prevalence of NRH in a database of liver biopsies (LBs) and the frequency of portal hypertension (PHT) at diagnosis, and (ii) to investigate whether associated diseases and/or specific histological lesions, including abnormalities of the microvasculature, were related to PHT.

METHODS

Patients with a histological diagnosis of NRH, referred by seven clinical departments, were retrospectively selected. Clinical, biological, radiological, haemodynamic and endoscopic data at diagnosis were recorded. LBs were reassessed for microvascular abnormalities.

RESULTS

NRH was diagnosed in 4.4% of LBs (n = 159, male: 52%, mean age: 54). Among patients referred for unexplained liver enzyme abnormalities, 15% had NRH. PHT was present at diagnosis in 45 patients (38%), including 13 with portal thrombosis; 65% of patients had an associated disorder. Obliteration of portal vein branches, observed in the LBs of 17 patients (11%), was significantly associated with PHT (P = 0.02). Periportal angiomatosis, observed in 101 patients (63%), was associated with the absence of PHT (P < 10(-4) ).

CONCLUSION

We suggest that NRH is a frequent histological lesion in the setting of unexplained liver enzyme abnormalities. PHT is present at the time of diagnosis in 1/3 of patients regardless of the presence of associated disease. The frequency of periportal angiomatosis in NRH without obliteration of portal vein branches, and its association with the absence of PHT suggest that obstructive portal venopathy would not represent the most frequent mechanism involved in NRH.

Methylenetetrahydrofolate reductase C677T gene mutation and hyperhomocysteinemia in Budd-Chiari syndrome and portal vein thrombosis: A systematic review and meta-analysis of observational studies

AIM

A systematic review and meta-analysis were conducted to explore the role of the methylenetetrahydrofolate reductase (MTHFR) C677T gene mutation and hyperhomocysteinemia in patients with Budd-Chiari syndrome (BCS) and portal vein thrombosis (PVT).

METHODS

PubMed, EMBASE, Cochrane Library and ScienceDirect databases were searched. Eligible studies should compare the prevalence of the MTHFR C677T mutation or hyperhomocysteinemia or the homocysteine levels between BCS or non-cirrhotic PVT patients and healthy controls or between cirrhotic patients with and without PVT. A pooled odds ratio or weighted mean difference with 95% confidence interval was calculated.

RESULTS

Of the 484 articles retrieved, 20 were included. BCS and non-cirrhotic PVT patients had a higher prevalence of homozygous MTHFR mutation than healthy controls. The difference was statistically significant in BCS patients, but not in non-cirrhotic PVT patients. BCS and non-cirrhotic PVT patients had a significantly higher prevalence of hyperhomocysteinemia and homocysteine level than healthy controls. Cirrhotic patients with PVT had a significantly higher prevalence of homozygous MTHFR mutation than those without PVT. However, the association between homocysteine level and PVT in cirrhotic patients was inconsistent among three studies.

CONCLUSION

Homozygous MTHFR mutation and hyperhomocysteinemia may be associated with the occurrence of BCS and non-cirrhotic PVT. In addition, homozygous MTHFR mutation may increase the risk of PVT in cirrhotic patients. However, the current evidence failed to support the association of hyperhomocysteinemia with PVT in cirrhotic patients.

Evaluation of the presence of hereditary and acquired thrombophilias in Brazilian children and adolescents with diagnoses of portal vein thrombosis

OBJECTIVE

The aim of this study was to describe the prevalence of main hereditary thrombophilias, Janus kinase 2 (JAK2) V617F mutation, antiphospholipid antibody syndrome (APS), and hyperhomocysteinemia in Brazilian children and adolescents diagnosed with portal vein thrombosis (PVT) without associated hepatic disease.

METHODS

A cross-sectional study was carried out with 32 children with PVT in accompaniment at Hospital das Clínicas of the Universidade Federal de Minas Gerais from January 1990 to July 2011. Laboratory evaluation of thrombophilias was performed from September 2010 to July 2011.

RESULTS

Thirty-two patients were evaluated; 59% were boys. Median age at diagnosis was 2.4 years. Mean time of patients' accompaniment was between 4.7 and 5.2 years. The presence of hereditary and acquired thrombophilias occurred in 34.4% of patients, and 9 of them also showed other risk factors in the previous history evaluation. Risk factors were absent in the previous history of 18 patients (56.3%). Two patients showed persistent high titres of anticardiolipin antibodies. Hyperhomocysteinemia was not observed. One patient was heterozygous for factor V Leiden and prothrombin G20210A mutation (3.1%). Eleven patients (34.4%) showed heterozygous methylenetetrahydrofolate reductase (MTHFR) C677T, and no patient had the JAK2V617F mutation.

CONCLUSIONS

Even after investigation of main hereditary and acquired thrombophilia, PVT remains without apparent cause in most patients. Nevertheless, association of local and systemic risk factors seems to be important also in the pediatric age group. Therefore, despite the low prevalence, a complete investigation, which includes both hereditary and acquired thrombophilias, may be necessary.

Liver transplantation for the treatment of nodular regenerative hyperplasia

BACKGROUND

Nodular regenerative hyperplasia (NRH) is the leading cause of non-cirrhotic portal hypertension in Western countries. Although some patients are successfully managed medically or with shunting procedures, others require liver transplantation. The aim of this review was to assess the overall results obtained with liver transplantation and to better define its role in this setting.

METHODS

Systematic review of all published studies on liver transplantation for NRH without language restrictions, in Medline, Embase and Cochrane Library databases through March 2010.

RESULTS

17 studies including a total of 73 patients were identified; 47 (64.3%) were excluded due to lacking inclusion criteria or clinical data and 26 (35.7%) were analysed. Before liver transplantation, the most frequent clinical presentation was gastroesophageal bleeding (65.3%) followed by ascites (61.5%), hepatic encephalopathy (30.7%) and liver failure (11.5%). The mean follow-up reported after liver transplantation was 30.6±27.6 months and patient and graft survival rate was 78.3%. Only one case reported a NRH recurrence 7 years after liver transplantation (LT).

CONCLUSIONS

Although there are no hard data supporting the role of liver transplantation in symptomatic NRH, onset of severe portal hypertension in this setting may represent a valid indication.

Nodular regenerative hyperplasia: Evolving concepts on underdiagnosed cause of portal hypertension

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.

Incidence of nodular regenerative hyperplasia in inflammatory bowel disease patients treated with azathioprine

BACKGROUND

Nodular regenerative hyperplasia (NRH) is a rare hepatic disorder that may lead to severe portal hypertension. Cases of NRH have been reported in patients receiving thiopurines for inflammatory bowel disease (IBD). Since azathioprine (AZA) is used more and more frequently as a maintenance treatment in IBD, the risk of NRH must be known. The objective of this study was to evaluate the prevalence of NRH and its predictive factors in IBD patients treated with AZA.

MATERIALS AND METHODS

From the same tertiary referral center, 1888 consecutive IBD patients treated with AZA were studied. Clinical diagnosis of NRH was proven by liver biopsy in all cases except one. The cumulative risk of NRH was estimated with the Kaplan-Meier method. Factors associated with NRH were tested independently with the log-rank method and multivariate proportional hazards model with time-dependent covariates.

RESULTS

Fifteen patients developed NRH in a median treatment duration of 52.4 months (SE 1.6). The cumulative incidence of NRH was 1.28±0.45% at 10 years. Only two variables were independently associated with NRH occurrence: male gender (P=0.0001, hazard ratio [HR] 8.5, 95% confidence interval [CI] 1.9-37.9) and small bowel resection≥50 cm (P<0.0001, HR 6.6, 95% CI 2.2-20.0), either prior to or after AZA initiation.

CONCLUSIONS

The risk of developing NRH during AZA treatment is low. This study suggests that male patients with small bowel resection≥50 cm constitute the group with the higher risk of developing NRH while treated with AZA.

Nodular regenerative hyperplasia of the liver: survival and associated features in a UK case series

AIMS

Nodular regenerative hyperplasia (NRH) is a rarely identified liver disorder. It is characterized histologically by nodular hepatocyte regeneration without significant fibrosis, and clinically by portal hypertension and abnormal liver function tests (LFTs). Survival data in an unselected cohort after diagnosis of NRH have not been previously described. This study aims to identify a regional cohort with NRH, to determine survival after diagnosis and to assess the relative frequency of associated conditions.

METHODS

Patients were identified retrospectively from liver biopsy reports within pathology databases, over a 13-year period from Glasgow, Scotland, UK. Case notes were retrieved, clinical information extracted and survival was determined.

RESULTS

Forty-two patients were identified (19 males). Common presenting features were abnormal LFTs (predominantly cholestatic) (76%) and portal hypertension (9.5%). None had severe liver dysfunction (Child-Pugh score A: 81%, B: 19%, C: 0%). Varices were detected in 26%, and portal hypertension was detected in 31%. There were five (12%) variceal bleeds, one fatal. The patients were subdivided into four groups according to associated clinical conditions: malignancy (29%), prothrombotic (21%), rheumatological (24%) and idiopathic/other (26%). Mean survival was 8.1 years, although survival was highly variable, and was associated with age and associated disease, but not with portal hypertension or varices. No patients in the rheumatological subgroup died.

CONCLUSION

NRH is usually associated with malignant, prothrombotic or rheumatological conditions. Survival is highly variable and related to age and the underlying disease process, but not to portal hypertension overall. Liver function remains well preserved.

6-thioguanine associated nodular regenerative hyperplasia in patients with inflammatory bowel disease may induce portal hypertension

BACKGROUND

Recent studies suggest an association between 6-thioguanine (6-TG) therapy and hepatic nodular regenerative hyperplasia (NRH) in patients with inflammatory bowel disease (IBD). An influence of 6-TG on portal pressure remains to be determined. The aim of the study was to examine the functional relevance of long-term 6-TG treatment on hepatic hemodynamics in IBD patients and its association with NRH.

METHODS

Patients treated with 6-TG for IBD underwent measurement of the hepatic venous pressure gradient (HVPG) and liver biopsy. 6-TG therapy was stopped when NRH was diagnosed. If elevated, HVPG measurement was repeated after 1 yr.

RESULTS

Twenty-six patients (15 women, 11 men; median age 41 yr, range 23-76) treated with 6-TG for 38 months (median; range 12-45) were included. Among 24 patients with sufficient liver biopsy, 6 patients (25%) were diagnosed with NRH. In these 6 patients, the HVPG was higher (median HVPG 7 mmHg, range 3-14) than in the 18 patients without NRH (median 3 mmHg, range 2-5; P < 0.001). In the patients with NRH, two had clinically significant portal hypertension (CSPH) (13 and 14 mmHg, respectively); in one patient the HVPG was slightly elevated (7 mmHg). No overt clinical signs of portal hypertension were observed. One year after stopping 6-TG therapy, HVPG decreased in all 3 patients with initially elevated HVPG levels.

CONCLUSIONS

We demonstrate that IBD patients under long-term 6-TG therapy are at a substantial risk for developing NRH. NRH results in elevation of HVPG and may cause CSPH. Discontinuation of 6-TG therapy extenuates portal hypertension and may thus reduce the risk of complications.

Nodular regenerative hyperplasia in patients with inflammatory bowel disease treated with azathioprine

AIM

To assess the characteristics and clinical course of nodular regenerative hyperplasia (NRH) in patients with inflammatory bowel disease treated with azathioprine, so as to estimate the frequency of this complication and search for risk factors.

METHODS

Cases were identified through a systematic survey of patients followed at 11 centres. At one centre, the cumulative risk of NRH was estimated and a case-control study was undertaken to identify risk factors.

RESULTS

37 cases of NRH (30 male, 7 female) were identified between 1994 and 2005. The median dose of azathioprine was 2 mg/kg/d (range 1.5 to 3.0). The median time between the start of azathioprine and the diagnosis of NRH was 48 months (range 6 to 187). After a median follow up period of 16 months (range 1 to 138), 14 patients developed complications of portal hypertension. Using multivariate analysis, male sex and stricturing behaviour were the two risk factors associated with NRH in patients treated with azathioprine. The cumulative risk calculated from the database (one centre) was 0.5% at 5 years (95% confidence interval, 0.11 to 0.89) and 1.25% at 10 years (0.29 to 2.21).

CONCLUSIONS

NRH is a rare but potentially severe complication of azathioprine in patients with inflammatory bowel disease. Clinicians should be aware of this complication, and should monitor liver function tests and platelet counts closely in their patients.

Nodular regenerative hyperplasia is a new cause of chronic liver disease in HIV-infected patients

OBJECTIVE

To describe and explain the syndrome of HIV-associated cryptogenic liver disease in eight consecutive patients suffering from portal hypertension.

METHODS

The study was undertaken at a liver disease centre in Paris and involved eight of 97 consecutive HIV-infected patients presenting abnormal liver function tests and/or symptomatic portal hypertension of unknown origin. Serology, pathology, and liver function tests were performed.

RESULTS

A clear nodular architecture corresponding to nodular regenerative hyperplasia was observed in seven patients and suggested in one, based on the presence of sinusoidal dilatation in a clinical context of portal hypertension, without overt liver disease.

CONCLUSIONS

Nodular regenerative hyperplasia appears to be a new cause of portal hypertension in HIV-infected patients. This syndrome can be of critical importance as patients can be exposed to the significant complications of portal hypertension and to refractory ascites which may require liver transplantation.

Evaluation of nonmalignant liver masses

Nonmalignant liver masses are increasingly being recognized with the widespread use of imaging modalities such as ultrasonography, computed tomography, and magnetic resonance imaging. The majority of these lesions are detected incidentally in asymptomatic patients. Based on the radiologic appearance, benign lesions can be categorized as solid or cystic, single or multiple, hypervascular or hypovascular. Based on histologic characteristics, they are classified as of hepatocellular, biliary, or mesenchymal origin. In the majority of patients, a proper diagnosis can be made based on these characteristics on imaging modalities alone. An invasive approach is seldom required. This review discusses the various characteristics of the most common benign liver lesions and recommends a practical approach.