Hepatoportal sclerosis as a cause of noncirrhotic portal hypertension in patients with HIV

A Narrative Review on Non-Cirrohotic Portal Hypertension: Not All Portal Hypertensions Mean Cirrhosis

Non-cirrhotic portal hypertension (NCPH), also known as idiopathic non-cirrhotic portal hypertension (INCPH) and porto-sinusoidal vascular disorder (PSVD), is a rare disease characterized by intrahepatic portal hypertension (IPH) in the absence of cirrhosis. The precise etiopathogenesis of IPH is an area of ongoing research. NCPH diagnosis is challenging, as there are no specific tests available to confirm the disease, and a high-quality liver biopsy, detailed clinical information, and an expert pathologist are necessary for diagnosis. Currently, the treatment of NCPH relies on the prevention of complications related to portal hypertension, following current guidelines of cirrhotic portal hypertension. No treatment has been studied that aimed to modify the natural history of the disease; however, transjugular intrahepatic porto-systemic shunt (TIPS) placement, shunt and liver transplantation are considerable symptomatic options. In this review, we discuss the heterogeneity of NCPH as well as its etiopathogenesis, clinical presentation and management issues. Starting from the assumption that portal hypertension does not always mean cirrhosis, cooperative studies are probably needed to clarify the issues of etiology and the possible genetic background of this rare disease. This knowledge might lead to better treatment and perhaps better prevention.

Portal Hypertension Due to Hepatoportal Sclerosis in an HIV-Positive Patient Secondary to Didanosine Use

Noncirrhotic portal hypertension (NCPH) has recently been found in human immunodeficiency virus (HIV)-infected patients taking didanosine. Here, we describe an HIV-infected patient with portal hypertension due to hepatoportal sclerosis who presented with hematemesis at the emergency department (ED). CT angiography of the abdomen and pelvis with and without contrast revealed a diminutive portal vein with corresponding massive lower esophageal varices and superior mesenteric vein to the right gonadal vein varices. Esophagogastroduodenoscopy (EGD) revealed grade II varices were found in the lower third of the esophagus, for which the patient's symptoms improved with emergency endoscopic band ligation, octreotide and didanosine discontinuation. Our case demonstrates a rare complication that can occur with continued didanosine use in an HIV-positive patient. We highlight the need for a standard diagnostic upper gastrointestinal endoscopy to screen for portal hypertension and high-risk esophageal varices in patients with long-term didanosine use as seen in our patient.

Aberrant von Willebrand factor expression of sinusoidal endothelial cells and quiescence of hepatic stellate cells in nodular regenerative hyperplasia and obliterative portal venopathy

AIMS

Nodular regenerative hyperplasia (NRH) and obliterative portal venopathy (OPV), entities that comprise idiopathic non-cirrhotic portal hypertension (INCPH), are under-recognised diseases of uncertain aetiology and the diagnosis can be easily missed on liver biopsy. The expression of CD34 and von Willebrand factor (vWF) in liver sinusoidal endothelial cells (LSEC) and alpha-smooth muscle actin (ASMA) in hepatic stellate cells (HSCs) is unknown in NRH and OPV. We sought to investigate the pathogenesis and potential immunomarkers that might aid in making the diagnosis of NRH and OPV.

METHODS AND RESULTS

Immunohistochemical (IHC) staining for CD34, vWF and ASMA was performed in clinically and histologically well-characterised NRH (n = 15) and OPV (n = 47) liver specimens. Among the 47 OPV cases, 37 (78.7%) had concurrent features of NRH. CD34 positive staining was mainly confined to small vessels in the portal tracts and LSECs in periportal areas, a finding similar to that in non-NRH/OPV livers. However, expression of vWF in LSECs was positive in the compressed sinusoids of NRH and in a patchy or geographic pattern, particularly prominent in the perivenular areas and dilated sinusoids of OPV cases. HSCs were negative for ASMA in all NRH and OPV cases.

CONCLUSION

Our findings indicate that NRH may be a subtle but common concurrent morphological feature in OPV. The aberrant expression of vWF in LSECs suggests that endothelial injury may play a role in the pathogenesis, which may thus aid in the recognition and diagnosis of NRH and OPV, particularly when confronted with otherwise apparent normal liver histology on needle biopsy.

Obliterative portal venopathy: A histopathologic finding associated with chronic antibody-mediated rejection in pediatric liver allografts

The significance of post-transplant HLA DSA and chronic AMR in LT is an emerging field of study. Although OPV has previously been described as a histopathologic finding in DSA-positive adult LT recipients, it was not included in the recent Banff criteria for chronic AMR. Our aim was to describe the association between OPV and chronic AMR in pediatric LT recipients. A retrospective review of 67 liver biopsies performed between November 2014 and April 2016 in 45 pediatric LT recipients identified four patients with OPV. Clinical status, liver biochemistry, the presence of DSA, and available non-HLA antibody testing, as well as histopathologic features of chronic AMR, were assessed. All four patients with OPV had class II DSA and histopathologic features of chronic AMR based on the Banff criteria. Two patients were noted to have non-HLA antibodies. Three patients are undergoing treatment with IVIG but have persistent DSA. Two patients have graft failure and are awaiting retransplantation. In conclusion, OPV is a histopathologic finding associated with chronic AMR in pediatric LT recipients. Further studies are needed to elucidate whether OPV is reversible and/or amenable to medical therapy.

Exposure to previous cART is associated with significant liver fibrosis and cirrhosis in human immunodeficiency virus-infected patients

Introduction

Combined antiretroviral therapy (cART) has improved survival in HIV-patients. While the first antiretrovirals, which became available in particular D-drugs (especially didanosine and stavudine) and unboosted protease inhibitors, may impair liver function, the modern cART seems to decrease liver fibrosis. This study assessed the influence of exposure to previous antiretrovirals on liver fibrosis in HIV-infected patients.

Methods

This observational cross-sectional single-center study recruited 333 HIV patients and assessed liver fibrosis using transient elastography (TE).

Results

83% were male with a median age of 45, while 131 were co-infected with viral hepatitis. Overall, 18% had significant fibrosis and 7.5% had cirrhosis. 11% of HIV mono-infected patients had significant fibrosis and 2% had cirrhosis. HCV infection (OR:5.3), history of exposure to didanosine (OR:2.7) and HIV load below 40copies/mL (OR:0.5) were independently associated with significant fibrosis, while HCV (OR:5.8), exposure to didanosine (OR:2.9) and azidothymidine (OR:2.8) were independently associated with cirrhosis. Interestingly, in HIV mono-infected patients, a HIV-load below 40copies/mL (OR:0.4) was independently associated with significant fibrosis, and didanosine (OR:20.8) with cirrhosis.

Conclusion

In conclusion, history of exposure to didanosine and azidothymidine continues to have an impact on the presence of liver cirrhosis in HIV patients. However, HCV co-infection and ongoing HIV-replication have the strongest effect on development of significant fibrosis in these patients.

Human Immunodeficiency Virus Infection, Antiretroviral Therapy, and Liver Pathology

The improvement in antiretroviral therapy has significantly impacted the lives of people living with human immunodeficiency virus (HIV). In high-income countries, HIV deaths are predominated by liver disease consequent to viral hepatitis coinfection, alcohol, and nonalcoholic fatty liver disease. Published liver pathology findings have shifted from being predominated by opportunistic infections to the metabolic effects of HIV and antiretroviral therapy as well as drug-induced liver injuries. Differences remain between high-income and low-income countries, where opportunistic infections and immune reconstitution syndromes, dominate findings.

Progression of Hepatic Adenoma to Carcinoma in the Setting of Hepatoportal Sclerosis in HIV Patient: Case Report and Review of the Literature

We report a case of hepatic adenoma progression to carcinoma in the setting of hepatoportal sclerosis in an HIV+ patient and provide a review of the scarce literature regarding hepatoportal sclerosis in HIV patients. We describe the clinical presentation, diagnostic workup, and management. This is the first case report in the literature of progression of hepatic adenoma to carcinoma in hepatoportal sclerosis in an HIV patient. This case also highlights the broad differential diagnosis that should always be included in the study of any liver disease in this patient population, including the performance of invasive and aggressive tests to arrive at the final diagnosis.

Human immunodeficiency virus and liver disease: An update

Human immunodeficiency viral (HIV) infection affects approximately 1.2 million persons in the United States and 35 million worldwide. Progression to advanced liver disease remains a leading cause of death among HIV-infected persons in the United States and elsewhere. Though mortality from HIV complications has been dramatically reduced wherever effective combination antiretroviral therapy is used, there has been little impact on liver-related mortality. Causes of liver disease in the setting of HIV infection include viral hepatitis, nonalcoholic fatty liver disease/nonalcoholic steatohepatitis, drug-associated toxicities, and other metabolic/genetic disorders which interact in an environment modulated by persistent immune activation and altered cytokine display.

CONCLUSION

Despite significant advances in treatment of hepatitis C virus and suppression of hepatitis B virus, treatment and management principles for liver disease in HIV-infected patients remain challenging; limited resources, fragmented health care, and high levels of injection drug use, alcohol use, and depression remain relevant issues in the HIV-infected patient.

Role of liver transplantation in human immunodeficiency virus positive patients

End-stage liver disease (ESLD) is a leading cause of morbidity and mortality amongst human immunodeficiency virus (HIV)-positive individuals. Chronic hepatitis B and hepatitis C virus (HCV) infection, drug-induced hepatotoxicity related to combined anti-retro-viral therapy, alcohol related liver disease and non-alcohol related fatty liver disease appear to be the leading causes. It is therefore, anticipated that more HIV-positive patients with ESLD will present as potential transplant candidates. HIV infection is no longer a contraindication to liver transplantation. Key transplantation outcomes such as rejection and infection rates as well as medium term graft and patient survival match those seen in the non-HIV infected patients in the absence of co-existing HCV infection. HIV disease does not seem to be negatively impacted by transplantation. However, HIV-HCV co-infection transplant outcomes remain suboptimal due to recurrence. In this article, we review the key challenges faced by this patient cohort in the pre- and post-transplant period.

Chronic liver disease in the human immunodeficiency virus patient

There are an estimated 40 million HIV infected individuals worldwide, with chronic liver disease being the 2nd leading cause of mortality in this population. Elevated liver functions are commonly noted in HIV patients and the etiologies are varied. Viral hepatitis B and C, fatty liver and drug induced liver injury are more common. Treatment options for viral hepatitis C are rapidly evolving and are promising, but treatments are limited for the other conditions and is primarily supportive. Opportunistic infections of the liver are now uncommon. Irrespective of etiology, management requires referral to specialized centers and with due diligence mortality can be reduced.

Idiopathic Non-Cirrhotic Intrahepatic Portal Hypertension (NCIPH)-Newer Insights into Pathogenesis and Emerging Newer Treatment Options

Chronic microangiopathy of portal venules results in idiopathic non-cirrhotic intrahepatic portal hypertension (NCIPH). Recent data suggest a role for vasoactive factors of portal venous origin in the pathogenesis of this 'pure' vasculopathy of the liver. Enteropathies (often silent), are an important 'driver' of this disease. NCIPH is under-recognized and often mis-labeled as cryptogenic cirrhosis. Liver biopsy is needed to prove the diagnosis of NCIPH. In these patients, with advancing disease and increased porto-systemic shunting, the portal venous vasoactive factors bypass the liver filter and contribute to the development of pulmonary vascular endothelial disorders-porto-pulmonary hypertension and hepato-pulmonary syndrome as well as mesangiocapillary glomerulonephritis. Prognosis in NCIPH patients is determined by presence, recognition and management of associated disorders. With better understanding of the pathogenesis of NCIPH, newer treatment options are being explored. Imbalance in ADAMTS 13 (a disintegrin and metalloprotease with thrombospondin type 1 motif, member 13): vWF (von-Willebrand factor) ratio is documented in NCIPH patients and may have a pathogenic role. Therapeutic interventions to correct this imbalance may prove to be important in the management of NCIPH.

Pregnancies after transjugular intrahepatic portosystemic shunt for noncirrhotic portal hypertension

With the growing role of transjugular intrahepatic portosystemic shunt (TIPS) in the management of portal hypertension complications, a number of women of childbearing age are now being treated with TIPS. However, if pregnancy is unusual in patients with cirrhosis, it can occur in the case of noncirrhotic portal hypertension. To our knowledge, there are no data on pregnancy safety after TIPS insertion. We report the first case of a patient with noncirrhotic portal hypertension treated by TIPS who had two successful pregnancies. She presented with HIV-associated obliterative portopathy with recurrent variceal bleeding treated by TIPS. Pregnancies occurred later and progressed normally without maternal or fetal morbidity. There was no effect on TIPS patency, but only a moderate increase in the flow velocity in the portal vein, the stent, and the hepatic artery. Thus, TIPS does not seem to impair progression of pregnancy.

Histopathologic manifestations of drug-induced hepatotoxicity

Drug-induced hepatotoxicity is underrecognized but increasingly identified as causing acute and chronic liver disease. Several prescription drugs, over-the-counter medications, dietary and/or supplementary agents, and herbal products are hepatotoxic. Drug-induced liver injury mimics other primary acute and chronic liver diseases and it should be considered in patients with hepatobiliary disease. Certain drugs result in specific histopathologic patterns of liver injury, which may help in sorting out the responsible drug. The diagnosis of drug-induced hepatotoxicity is challenging. It involves excluding other possible causes, careful medication history, the latent period between drug exposure and symptom onset and/or abnormal liver tests, and histopathologic findings.

Obliterative portal venopathy: a clinical and histopathological review

Non-cirrhotic portal hypertension (NCPH) is characterized by the elevation of the portal pressure in the absence of cirrhosis. Obliterative portal venopathy (OPV) as a cause of NCPH is being increasingly diagnosed, especially after recent reports of its occurrence in patients with HIV using didanosine. Patients usually present with episodes of variceal hemorrhage and other features of portal hypertension including jaundice, ascites, encephalopathy and hepatopulmonary syndrome. Hepatic synthetic function is typically well preserved and the laboratory evaluation in OPV patients typically reveals only mild nonspecific hematological abnormalities chiefly related to hypersplenism. Its diagnosis remains a challenge and patients are often mistakenly diagnosed as having cirrhosis. Despite the increasing recognition of OPV, its etiology and pathogenesis are still unclear. A number of etiologies have been proposed including genetic predisposition, recurrent bacterial infections, HIV infection and highly active antiretroviral therapy, an altered immune response, hypercoagulability, and exposure to chemicals and certain medications. Histopathological evaluation remains critical in excluding cirrhosis and other causes of portal hypertension, and is the only way of definitively establishing the diagnosis of OPV. Clinicians should have a high index of suspicion for OPV in patients who present with variceal bleeding and splenomegaly and who do not have other features of cirrhosis. The purpose of this review is to summarize the known etiologies for OPV and its associated clinical aspects and correlations, and to also provide ample histophotomicrographs of OPV to aid in the diagnosis. It will also help raise awareness of this entity amongst pathologists and clinicians alike.

Hepatoportal sclerosis in childhood: descriptive analysis of 12 patients

Hepatoportal sclerosis (HPS) is defined as sclerosis of portal areas in the absence of cirrhosis. There is little information about HPS in children in the literature. The aim of this study was to describe the clinical presentation, associated disorders, laboratory characteristics and outcome of children who were diagnosed as HPS. This study included 12 children diagnosed as HPS by the Pathology Department between 2005 and 2011. Data were collected from the gastroenterology clinic charts retrospectively, including demographics, presentation characteristics, laboratory data and recent status of patients. Twelve patients were enrolled (6 girls, 6 boys). The median age of patients was 13.5 yr. Median age at the time of biopsy was 11 yr. Four patients had splenomegaly, 3 had esophageal varices, one had hepatopulmonary syndrome and had been transplanted. Smooth muscle antibody was found positive in 4 patients, without autoimmune hepatitis findings in liver biopsy. One patient had celiac disease and another patient had positive celiac disease serology but pathology findings. Another patient had Turner's syndrome. Mean follow-up time was 39 months (3.3 yr) after biopsy. Hepatoportal sclerosis does not necessarily present with portal hypertension in children.

Hepatoportal sclerosis (obliterative portal venopathy) and nodular regenerative hyperplasia in a patient with myasthenia gravis: A case report and review of the published work

Nodular regenerative hyperplasia (NRH) and hepatoportal sclerosis, also known as obliterative portal venopathy (OPV), are two causes of non-cirrhotic portal hypertension (NCPH). NCPH is an increasingly recognized entity that can be seen in association with collagen vascular diseases and with the use of medications such as azathioprine and didanosine, but oftentimes the etiology remains unidentified. We herein report a case of NCPH occurring due to OPV and NRH in a 64-year-old woman with myasthenia gravis (MG), status post-thymectomy. Portal hypertension was diagnosed incidentally on computed tomography in the absence of predisposing factors. Extensive work-up to determine the etiology of any underlying liver disease was unrevealing. NRH and OPV were identified on liver biopsy. Subsequently, the patient had variceal bleeding that necessitated transjugular intrahepatic portosystemic shunt placement. A few similar cases of NCPH occurring in the setting of MG have been previously reported, suggesting that the immunological mechanisms involved in the pathogenesis of myasthenia may also have contributed to the development of NCPH.

Mercaptopurine-induced hepatoportal sclerosis in a patient with Crohn's disease

Thiopurines play a pivotal role in the management of inflammatory bowel disease. Azathioprine and mercaptopurine have been associated with a number of liver abnormalities, including hepatitis, veno-occlusive disease, nodular regenerative hyperplasia, and peliosis hepatitis. Patients treated with azathioprine and mercaptopurine have their liver chemistry tests routinely checked due to this potential for hepatotoxicity. Hepatoportal sclerosis is a cause of non-cirrhotic portal hypertension that is increasingly being recognized; its etiopathogenesis is not well defined. We present the first case report of mercaptopurine-induced hepatoportal sclerosis leading to non-cirrhotic portal hypertension in a patient with Crohn's disease. He had been treated with mercaptopurine for five years, and his liver chemistry tests were always within normal limits. This case underscores the potential serious liver adverse events that may arise silently and go undetected during treatment with mercaptopurine, and should alert clinicians as to the potential need to discontinue mercaptopurine in this setting.

Incidence of liver damage of uncertain origin in HIV patients not co-infected with HCV/HBV

Background and Aims

Several studies have reported that a significant number of HIV patients not co-infected with HCV/HBV develop liver damage of uncertain origin (LDUO). The objective of our study was to evaluate the incidence of and risk factors for the development of LDUO in HIV infected patients not co-infected with HCV/HBV.

Methods

Prospective longitudinal study that included HIV-infected patients free of previous liver damage and viral hepatitis B or C co-infections. Patients were followed up at 6-monthly intervals. Liver stiffness was measured at each visit. Abnormal liver stiffness (ALS) was defined as a liver stiffness value greater than 7.2 kPa at two consecutive measurements. For patients who developed ALS, a protocol was followed to diagnose the cause of liver damage. Those patients who could not be diagnosed with any specific cause of liver disease were diagnosed as LDUO and liver biopsy was proposed.

Results

210 patients matched the inclusion criteria and were included. 198 patients completed the study. After a median (Q1–Q3) follow-up of 18 (IQR 12–26) months, 21 patients (10.6%) developed ALS. Of these, fifteen patients were diagnosed as LDUO. The incidence of LDUO was 7.64 cases/100 patient-years. Histological studies were performed on ten (66.6%) patients and all showed liver steatosis. A higher HOMA-IR value and body mass index were independently associated with the development of LDUO.

Conclusion

We found a high incidence of LDUO in HIV-infected patients associated with metabolic risk factors. The leading cause of LDUO in our study was non-alcoholic fatty liver disease.

Drug-induced cholestasis

Cholestasis caused by drugs is an important differential diagnosis in patients presenting with a biochemical cholestatic pattern. The extent of serologic tests and radiological imaging depends on the clinical context. The underlying condition of the patient and detailed information on drug use, results of rechallenge, and the documented hepatotoxicity of the drug are important to establish a diagnosis of drug-induced liver injury (DILI). Most cases of cholestatic DILI are mild, but in rare cases, ductopenia and cholestatic cirrhosis can develop. Approximately 10% of patients with cholestatic jaundice caused by drugs develop liver failure.

Genetic determinants of idiopathic noncirrhotic portal hypertension in HIV-infected patients

BACKGROUND

Noncirrhotic portal hypertension (NCPH) is a rare but potentially life-threatening complication in patients with human immunodeficiency virus (HIV). Cases of NCPH have been reported in HIV-negative individuals as result of treatment with thiopurines for leukemia or inflammatory bowel disease. Exposure to didanosine, which is also a purine analogue, predisposes to NCPH in the HIV setting. However, it is unclear why NCPH only develops in a small subset of didanosine-treated patients.

METHODS

A multicenter, case-control study was conducted to investigate the role of pharmacogenomics in NCPH in HIV patients with prior didanosine exposure. Three controls were chosen for each case, adjusted for sex, age, CD4 counts, plasma HIV-RNA, and site. Tagging 36 single-nucleotide polymorphisms (SNPs) at enzymes involved in the purine metabolism (inosine triphosphatase, 5'-nucleotidase cytosolic-II, purine nucleoside phosphorylase and xanthine oxidase) was performed using SNPlex microarray technology.

RESULTS

Eighty individuals were examined; 22 with NCPH and 58 matched controls. Two SNPs at the 5'-nucleotidase gene were associated with NCPH: rs11191561 (48% CG/GG vs 17% CC; P=.003) and rs11598702 (40% CC/CT vs 9% TT; P=.003). SNPs at another 2 loci at the xanthine oxidase gene were also associated with NCPH: rs1429376 (71% AA vs 23% CC/AC; P=.015) and rs1594160 (71% AA vs 23% CC/AC; P=.015). There was a cumulative risk of NCPH for these 4 SNPs: 7%, 26%, 42%, 50%, and 100%, respectively, for 0, 1, 2, 3, or all SNPs (P=.001).

CONCLUSIONS

SNPs at the 5'-nucleotidase and xanthine oxidase genes influence the risk of NCPH in HIV patients treated with didanosine.

Risk factors and outcome of HIV-associated idiopathic noncirrhotic portal hypertension

BACKGROUND

Idiopathic noncirrhotic portal hypertension (INCPH) has been reported increasingly in patients with HIV infection.

AIM

To evaluate the number of nationwide diagnosed HIV-associated INCPH cases and to assess its clinical features, risk factors and outcome.

METHODS

All HIV centres in the Netherlands were contacted and requested to notify INCPH cases diagnosed in their population. A case–control study was performed to identify the risk factors of INCPH. The cases were group-matched for duration of follow-up after HIV diagnosis to controls. Controls were selected from a database of HIV patients with negative screening for signs of portal hypertension on abdominal ultrasound. Univariate and multivariate conditional logistic regression analyses were performed.

RESULTS

On 1st of July 2011, 18.085 individuals were infected with HIV in the Netherlands. Within this population, sixteen patients with clinically overt INCPH were identified. At the time of INCPH diagnosis, cases had a lower platelet count and a higher ALT level. In univariate and multivariate analyses, didanosine [OR: 1.9 (1.3–2.8)], concomitant didanosine and stavudine treatment [OR: 6.3 (2.1–19.1)] and concomitant didanosine and tenofovir treatment [OR: 5.1 (1.2–22.6)] were independently associated INCPH. During follow-up, 4 patients died [malignancy (n = 3), liver failure (n = 1)]. A significant decline in platelets was observed after didanosine discontinuation (P = 0.003).

CONCLUSIONS

HIV-associated clinically relevant idiopathic noncirrhotic portal hypertension appears to be a rarely diagnosed disease. Long-term exposure to didanosine and short-term combination of didanosine and stavudine or tenofovir exposure are associated with idiopathic noncirrhotic portal hypertension. Mortality in HIV-associated idiopathic noncirrhotic portal hypertension is mainly related to HIV-associated disorders. Portal hypertension continues despite didanosine discontinuation

Antiretroviral drug-related liver mortality among HIV-positive persons in the absence of hepatitis B or C virus coinfection: the data collection on adverse events of anti-HIV drugs study

BACKGROUND

Liver diseases are the leading causes of death in human immunodeficiency virus (HIV)-positive persons since the widespread use of combination antiretroviral treatment (cART). Most of these deaths are due to hepatitis C (HCV) or B (HBV) virus coinfections. Little is known about other causes. Prolonged exposure to some antiretroviral drugs might increase hepatic mortality.

METHODS

All patients in the Data Collection on Adverse Events of Anti-HIV Drugs study without HCV or HBV coinfection were prospectively followed from date of entry until death or last follow-up. In patients with liver-related death, clinical charts were reviewed using a structured questionnaire.

RESULTS

We followed 22 910 participants without hepatitis virus coinfection for 114 478 person-years. There were 12 liver-related deaths (incidence, 0.10/1000 person-years); 7 due to severe alcohol use and 5 due to established ART-related toxicity. The rate of ART-related deaths in treatment-experienced persons was 0.04/1000 person-years (95% confidence interval, .01, .10).

CONCLUSIONS

We found a low incidence of liver-related deaths in HIV-infected persons without HCV or HBV coinfection. Liver-related mortality because of ART-related toxicity was rare.

Non-cirrhotic portal hypertension in HIV mono-infected patients

BACKGROUND AND AIM

Unexplained liver injury including fibrosis and portal hypertension has rarely been reported among patients with HIV in the absence of co-infection with hepatitis B (HBV) or hepatitis C (HCV). We describe a series of HIV mono-infected patients with evidence of non-cirrhotic portal hypertension.

METHODS

HIV-infected patients with evidence of portal hypertension who were anti-HBV and anti-HCV negative and HBV and HCV RNA polymerase chain reaction (PCR) negative were identified from patients managed by the Victorian statewide HIV referral service located at The Alfred Hospital, Melbourne. Portal hypertension was defined as either radiological or endoscopic evidence of varices, portal vein flow obstruction, or elevated hepatic venous pressure gradient (HPVG).

RESULTS

Five patients were found to have portal hypertension. These patients were male, aged 41 to 65 years, with known duration of HIV infection between 11 to 25 years. All had been treated with antiretroviral therapy, including didanosine. Tests for metabolic, autoimmune, and hereditary causes of liver disease failed to establish an etiology for the liver injury. All had radiological or endoscopic findings of varices, and four patients had radiological features of portal vein obstruction or flow reversal. Only one patient underwent HPVG measurement, which was elevated. Non-invasive fibrosis assessment revealed increased liver stiffness in three (out of four) patients, and no cirrhotic features were found on those who underwent liver biopsy.

CONCLUSIONS

To our knowledge, this is the largest published series of non-cirrhotic portal hypertension in HIV mono-infected patients in Australia. Further research is needed to understand what relationship, if any, HIV or its treatments might have on liver injury over time.

Histopathologic evaluation of liver biopsy for cirrhosis

In current medical practice, the clinical diagnosis of cirrhosis is rendered when a patient has suggestive imaging findings or features of portal hypertension (pHTN). Liver biopsy may be considered to assess potential underlying cause(s). Cirrhosis, however, is not the only etiology of pHTN; in fact, schistosomiasis remains a significant factor worldwide. pHTN results from obstruction of hepatic blood flow; it is classified clinically based on either the anatomic location of obstruction or hepatic venous pressure gradient measurements. The clinical categories carry clinicopathologic significances. Histopathologically, pHTN is manifest with either cirrhotic or noncirrhotic features. Noncirrhotic pHTN results from a heterogeneous group of disease processes, all of which result in vascular remodeling with variable parenchymal nodularity and fibrosis. This review summarizes liver biopsy findings of cirrhosis and possible etiologies and provides a stepwise approach for the histologic differential diagnosis of a liver biopsy done for "cirrhosis."

Management of hepatic vascular diseases

Primary damage to hepatic vessels is rare. (i) Hepatic arterial disorders, related mostly to iatrogenic injury and occasionally to systemic diseases, lead to ischemic cholangiopathy. (ii) Hepatic vein or inferior vena cava thrombosis, causing primary Budd-Chiari syndrome, is related typically to a combination of underlying prothrombotic conditions, particularly myeloproliferative neoplasms, factor V Leiden, and oral contraceptive use. The outcome of Budd-Chiari syndrome has markedly improved with anticoagulation therapy and, when needed, angioplasty, stenting, TIPS, or liver transplantation. (iii) Extrahepatic portal vein thrombosis is related to local causes (advanced cirrhosis, surgery, malignant or inflammatory conditions), or general prothrombotic conditions (mostly myeloproliferative neoplasms or factor II gene mutation), often in combination. Anticoagulation at the early stage prevents thrombus extension and, in 40% of the cases, allows for recanalization. At the late stage, gastrointestinal bleeding related to portal hypertension can be prevented in the same way as in cirrhosis. (iv) Sinusoidal obstruction syndrome (or venoocclusive disease), caused by agents toxic to bone marrow progenitors and to sinusoidal endothelial cells, induces portal hypertension and liver dysfunction. Decreasing the intensity of myeloablative regimens reduces the incidence of sinusoidal toxicity. (v) Obstruction of intrahepatic portal veins (obliterative portal venopathy) can be associated with autoimmune diseases, prothrombotic conditions, or HIV infection. The disease can eventually be complicated with end-stage liver disease. Extrahepatic portal vein obstruction is common. Anticoagulation should be considered. (vi) Nodular regenerative hyperplasia is induced by the uneven perfusion due to obstructed sinusoids, or portal or hepatic venules. It causes pure portal hypertension.

Hepatoportal sclerosis: CT and MRI appearance with histopathologic correlation

OBJECTIVE

The purposes of this study were to describe the spectrum of cross-sectional imaging findings of pathologically proven hepatoportal sclerosis and to compare the features of advanced and nonadvanced hepatoportal sclerosis.

MATERIALS AND METHODS

Eighteen patients with a histopathologic diagnosis of hepatoportal sclerosis who had concurrent MRI or CT images participated in the study. The following imaging features were assessed: presence of liver nodularity and liver lesions, portal vein patency, presence and degree of portal hypertension, liver volume, and caudate-to-right lobe ratio. These features were compared between patients who underwent transplant and those who did not.

RESULTS

The 18 patients (11 men and one boy, six women; mean age, 46.5 years) had hepatoportal sclerosis confirmed with liver biopsy (14 patients) or explant (four patients). Fourteen patients underwent contrast-enhanced MRI, and five underwent CT. The imaging findings were as follows: liver surface nodularity, five patients (all four transplant, one nontransplant) (p = 0.0016); evidence of portal hypertension, 17 patients; increased caudate-to-right lobe ratio, 16 patients; high periportal signal intensity on T2-weighted images, six patients; portal vein occlusion with cavernous transformation, five patients. The transplant patients had smaller pretransplant liver volume than did nontransplant patients (p < 0.04).

CONCLUSION

Hepatoportal sclerosis is characterized by caudate lobe hypertrophy and right hepatic lobe atrophy, preserved liver volume, and lack of the liver nodularity associated with portal hypertension. In advanced cases, liver nodularity and atrophy produce an imaging appearance indistinguishable from that of cirrhosis.

Obliterative portal venopathy: findings at CT imaging

PURPOSE

To retrospectively analyze the computed tomographic (CT) findings in a single-center series of adult patients with biopsy-proved obliterative portal venopathy (OPV) and to compare them with those observed in patients with cirrhosis.

MATERIALS AND METHODS

The requirement for informed consent was waived. This institutional review board-approved study included 42 consecutive patients with a histologically proved diagnosis of OPV who underwent CT at diagnosis. The clinical characteristics at diagnosis were recorded, and CT examination results were reviewed. Two radiologists evaluated portal vein patency and intrahepatic portal branches, the morphologic changes in the liver, the presence of hepatic nodules, and signs of portal hypertension in consensus. The control group consisted of 42 patients who had histologically proved cirrhosis. CT findings were compared between the OPV patient group and the cirrhotic group and also among the conditions associated with patients with OPV. The Fisher exact test was used. P values of .05 or less were considered to indicate significant differences.

RESULTS

The following CT findings were observed significantly more frequently in OPV than in cirrhosis: extrahepatic portal vein thrombosis (18 [43%] of 42 vs five [12%] of 42); intrahepatic portal abnormalities (18 [58%] of 31 vs one [2%] of 42) such as reduced caliber, occlusive thrombosis, and lack of visibility; focal nodular hyperplasia-like nodules (six [14%] of 42 vs 0 [0%] of 42); and perfusion disorders (15 [36%] of 42 vs six [14%] of 42). Conversely, the combination of hypertrophy of the caudate lobe and atrophy of segment IV (27 [64%] of 42 vs 10 [24%] of 42) and nodular surface (37 [88%] of 42 vs seven [17%] of 42) were seen significantly more often in cirrhosis.

CONCLUSION

Characteristic CT findings in patients with OPV that differ from those in patients with cirrhosis were shown, the most common being the presence of intra- or extrahepatic portal abnormalities.

Human immunodeficiency virus infection and the liver

Liver disease in human immunodeficiency virus (HIV)-infected individuals encompasses the spectrum from abnormal liver function tests, liver decompensation, with and without evidence of cirrhosis on biopsy, to non-alcoholic liver disease and its more severe form, non-alcoholic steatohepatitis and hepatocellular cancer. HIV can infect multiple cells in the liver, leading to enhanced intrahepatic apoptosis, activation and fibrosis. HIV can also alter gastro-intestinal tract permeability, leading to increased levels of circulating lipopolysaccharide that may have an impact on liver function. This review focuses on recent changes in the epidemiology, pathogenesis and clinical presentation of liver disease in HIV-infected patients, in the absence of co-infection with hepatitis B virus or hepatitis C virus, with a specific focus on issues relevant to low and middle income countries.

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.

Non-cirrhotic portal hypertension in HIV-infected individuals

Non-cirrhotic portal hypertension (NCPH) has been associated with didanosine (ddI) exposure. We aimed to determine the number of individuals with NCPH within our cohort and define their characteristics. We identified individuals within our cohort with NCPH and performed a retrospective case note review. Cumulative antiretroviral therapy (ART) use was calculated and a statistical analysis performed to compare exposure to the rest of the clinic cohort for the same time period. Where available, data was collated on FibroScan®, echocardiography and coagulation profile. Seventeen patients were identified. Upper gastrointestinal bleeding was the most common presenting feature. Liver biopsy showed mild portal or periportal fibrosis in 13 (81%) and four with features of nodular regenerative hyperplasia. There was significantly greater exposure to ddl in this group (59.5 months) compared to the rest of the HIV cohort (21.1 months) P = <0.001. Eleven subjects has a liver elastography performed, six (55%) had a result greater than 9.6 kPa (consistent with greater than F2 disease by Metavir scoring). Echocardiography was performed in seven patients: four met criteria for pulmonary hypertension. This is consistent with other cohorts demonstrating an association between the didanosine exposure and NCPH. Our data also suggest an increased risk of pulmonary hypertension.

Model for end-stage liver disease exceptions in the context of the French model for end-stage liver disease score-based liver allocation system

Model for End-Stage Liver Disease (MELD) score-based allocation systems have been adopted by most countries in Europe and North America. Indeed, the MELD score is a robust marker of early mortality for patients with cirrhosis. Except for extreme values, high pretransplant MELD scores do not significantly affect posttransplant survival. The MELD score can be used to optimize the allocation of allografts according to a sickest first policy. Most often, patients with small hepatocellular carcinomas (HCCs) and low MELD scores receive extra points, which allow them appropriate access to transplantation comparable to the access of patients with advanced cirrhosis and high MELD scores. In addition to patients with advanced cirrhosis and HCC, patients with a number of relatively uncommon conditions have low MELD scores and a poor prognosis in the short term without transplantation but derive excellent benefits from transplantation. These conditions, which correspond to the so-called MELD score exceptions, justify the allocation of a specific score for appropriate access to transplantation. Here we report the conclusions of the French consensus meeting. The goals of this meeting were (1) to identify which conditions merit MELD score exceptions, (2) to list the criteria needed for defining each of these conditions, and (3) to define a reasonable time interval for organ allocation for each MELD exception in the general context of organ shortages. MELD exceptions were discussed in an attempt to reconcile the concepts of transparency, equity, justice, and utility.

Influence of antiretroviral therapy on liver disease

PURPOSE OF REVIEW

Liver disease is a major cause of morbidity and mortality in HIV-infected persons. The long-term beneficial versus potentially harmful influence of antiretroviral therapy (ART) on the liver is debated. We review current data on factors contributing to liver disease in HIV-monoinfected as well as in HIV/viral hepatitis-coinfected patients, highlighting the role of ART, HIV itself, immunodeficiency, patient characteristics, and lifestyle risk factors.

RECENT FINDINGS

New ART-related clinical syndromes, including noncirrhotic portal hypertension and nonalcoholic fatty liver disease, have emerged, and observational data suggest long-term ART-associated liver injury. Recently, there is increasing evidence that HIV itself and immunosuppression are contributing to liver injury in both HIV-coinfected and HIV-monoinfected patients. In HIV-positive persons, ART attenuates progression of chronic viral hepatitis.

SUMMARY

Current expert guidelines recommend earlier treatment of HIV infection in persons coinfected with hepatitis B virus and possibly hepatitis C virus. It is unknown whether an earlier start of ART is beneficial for the liver in HIV-monoinfected patients. Future research should focus on long-term ART-related hepatotoxicity.

Idiopathic noncirrhotic portal hypertension

Idiopathic noncirrhotic portal hypertension (INCPH) is characterized by an increased portal venous pressure gradient in the absence of a known cause of liver disease and portal vein thrombosis. In contrast to the high prevalence of this disorder in India, INCPH is a rare disease in the Western world. The etiology of INCPH can be divided in five categories: chronic infections, exposure to medication or toxins, thrombophilia, immunological disorders, and genetic disorders. Multifactorial etiology can also be encountered. Chronic abdominal infection is incriminated as the most important etiological factor in Eastern patients and thrombophilia in Western patients. The majority of patients with INCPH initially present with signs or complications of portal hypertension (mainly variceal bleeding and splenomegaly). These patients usually have preserved liver function. Liver function impairment occurs mainly in the context of intercurrent conditions. Patients with INCPH are often clinically and radiologically misdiagnosed as liver cirrhosis, so that a liver biopsy is indispensable to discriminate cirrhosis from INCPH. Histopathological characteristics of INCPH are heterogeneous, demonstrating overlap between several pathological entities (e.g., hepatoportal sclerosis, nodular regenerative hyperplasia, and incomplete septal cirrhosis). Even though hemodynamical changes in INCPH patients are not comparable to those in cirrhotics, prophylaxis and treatment of variceal bleeding are recommended to be similar. Anticoagulation therapy must be considered only in patients who develop portal vein thrombosis. INCPH has been considered a disorder with a relatively benign disease course. However, liver failure, hepatic encephalopathy, and hepatopulmonary syndrome can occur and are considered indications for liver transplantation.

Liver transplantation in human immunodeficiency virus-positive patients

With the successful introduction of combined antiretroviral therapy (cART), human immunodeficiency virus (HIV) is now regarded as a chronic illness with excellent long-term outcomes. However, chronic exposure to viral etiologies (ie, chronic hepatitis B and hepatitis C) and drug-induced toxicity secondary to cART have resulted in increasing rates of mortality and morbidity due to end-stage liver disease. HIV disease is no longer considered an absolute contraindication to liver transplantation (LT) by most transplant centers worldwide. Because the burden of liver disease in this cohort is likely to increase, this review addresses the key etiologies and the management strategies available for HIV-positive patients undergoing LT.

Significance of isolated hepatic veno-occlusive disease/sinusoidal obstruction syndrome after liver transplantation

After liver transplantation (LT), hepatic veno-occlusive disease (VOD), which is also known as sinusoidal obstruction syndrome (SOS), has been reported initially in relation to azathioprine use and subsequently in relation to acute rejection (AR). Isolated veno-occlusive disease (iVOD)/SOS raises some questions about its significance and especially its treatment. From the post-LT biopsy samples of 1364 patients (2000-2008), 31 patients with index biopsy samples showing VOD/SOS (2.3%) were identified. After a review of the index biopsy samples and previous biopsy samples, those patients not exposed to azathioprine therapy were subdivided into 2 groups according to the absence or presence of AR. Fifteen of the 31 patients had no previous evidence of AR, whereas 16 experienced episodes of AR (before or concurrently with VOD). The 2 groups were similar in terms of demographic and clinical data and the range of histological centrilobular changes. AR episodes were characterized by an endothelial predilection. iVOD/SOS occurred later than acute rejection-related veno-occlusive disease (AR-VOD)/SOS (mean times of 65 and 4.4 months, respectively, P = 0.0098). There was a tendency for iVOD/SOS to progress less frequently to chronic rejection in comparison with AR-VOD/SOS (3/15 versus 9/15, P = 0.06). The histological resolution of iVOD/SOS was significantly more frequent in patients who benefited from increased immunosuppression in comparison with those who did not (5/7 versus 2/8, P = 0.05). When the groups were considered together, the same result was obtained (14/18 versus 4/12, P = 0.024). In conclusion, despite a constant overall prevalence of VOD/SOS, the proportion of iVOD/SOS has increased. The histological resolution of iVOD/SOS after increase in immunosuppression suggests an immune-mediated origin. Better optimization of immunosuppression may be a curative treatment.

Elevated levels of circulating angiotensin converting enzyme in patients with hepatoportal sclerosis

BACKGROUND AND AIMS

Hepatoportal sclerosis (HPS) is a clinicopathologic condition that is clinically characterized by portal hypertension (varices and portosystemic collateral vessels), splenomegaly and pancytopenia, in the absence of cirrhosis. Although the etiology is obscure, a number of theories such as immunologic and vascular endothelial cellular abnormalities have been put forward to explain the underlying pathophysiology. Angiotensin-converting enzyme (ACE), an important molecule of the renin-angiotensin system (RAS), is also known as a regulatory molecule in systemic and portal circulation in distinct disorders. The aim of the present study was to investigate the possible role of the ACE in the context of RAS in HPS pathogenesis.

MATERIALS AND METHODS

The study was conducted on 30 HPS patients (16 men, 14 women; median age 36 years, range 18-63) and 20 healthy controls. The clinical features of HPS patients including demographics, laboratory, and ultrasonography findings were summarized. Serum ACE levels were measured by using commercially available kits.

RESULTS

Serum median ACE levels were 36 (8-174) U/l and 16 (8-43) U/l for the HPS patients and controls, respectively. Serum ACE levels were significantly higher in patients with HPS compared to the control group (P < 0.05).

CONCLUSION

ACE in the context of RAS may be associated with pathological endothelial occlusive events in the microenvironment of the portal circulation in HPS. Revealing the interactions between circulating and local RAS within the hepatic microenvironment would enlighten the biologic basis and clinical management of liver diseases.

Non-cirrhotic portal hypertension in human immunodeficiency virus-infected patients: a new challenge in antiretroviral therapy era

Non-cirrhotic portal hypertension (NCPH) has been recently reported as a liver disease in Human Immunodeficiency Virus (HIV)-infected patients under antiretroviral therapy (ART). Combination of non-exclusive mechanisms has been described: primary endothelial damage of terminal portal veins induced by HIV or immunologic disorders, mitochondrial toxicity by didanosine and prothrombotic state. It is characterized by heterogeneous liver histological findings, frequently identified as nodular regenerative hyperplasia and clinical manifestations of portal hypertension with well-preserved liver function. We describe herein two HIV-infected patients with clinical picture suggestive of NCPH. Besides the case reports, we briefly address questions to apply to patient care in clinical practice.

Noncirrhotic portal hypertension in HIV infection

PURPOSE OF REVIEW

Liver disease in the HAART era is one of the leading causes of morbidity and mortality in HIV-infected individuals in Western countries. Even if the majority of cases rely on identifiable causes (viral hepatitis, steatohepatitis, alcohol abuse, drug toxicity, etc.), the cause of liver abnormalities remains unknown for a subset of patients, some of whom present with noncirrhotic portal hypertension (NCPH).

RECENT FINDINGS

In 2006, the first reports of NCPH in HIV-infected patients attracted special attention. Typically, individuals unaware of any underlying liver illness presented with variceal bleeding, occasionally fatal. Interestingly, severe portal hypertension occurred in the absence of liver function impairment in most cases. Liver biopsy revealed a distinctive histological feature characterized by massive absence of portal veins along with focal obliteration of small portal veins. After extensive ruling out of other causes, the role of antiretroviral toxicity (particularly didanosine exposure) emerged as the major contributor to this condition. Other potential factors could be an enhanced microbial translocation from the gut and prothrombotic conditions.

SUMMARY

NCPH is an uncommon condition, although increasingly being reported in HIV-infected individuals. It generally presents as a clinical episode of decompensated portal hypertension, generally with gastrointestinal bleeding. Long-lasting HIV infection and prolonged antiretroviral exposure are universally recognized in these patients. The involvement of didanosine has been highlighted in most series. Removal of this drug and prevention of variceal bleeding episodes are currently the most effective prophylactic and therapeutic interventions.

Increasing burden of liver disease in patients with HIV infection

Introduction of effective combined antiretroviral therapy has made HIV infection a chronic illness. Substantial reductions in the number of AIDS-related deaths have been accompanied by an increase in liver-related morbidity and mortality due to co-infection with chronic hepatitis B and C viruses. Increases in non-alcoholic fatty liver disease and drug-induced hepatotoxicity, together with development of hepatocellular carcinoma, also potentiate the burden of liver disease in individuals with HIV infection. We provide an overview of the key causes, disease mechanisms of pathogenesis, and recommendations for treatment options including the evolving role of liver transplantation.