Idiopathic non cirrhotic portal hypertension and spleno-portal axis abnormalities in patients with severe primary antibody deficiencies

[Portosinusoidal vascular disorder: A paradigm shift]

The term portosinusoidal vascular disorder (PSVD) refers to a clinical-pathological entity that encompasses those patients with intrahepatic vascular damage without cirrhosis at risk of developing severe complications of portal hypertension. Numerous systemic diseases, genetic disorders, and toxic agents have been associated with this pathology, making its diagnosis an important clinical challenge. The recent description of uniform diagnostic criteria and a better understanding of its pathophysiology will allow for better identification of patients, even in early stages of the disease. Although there is currently no effective etiological treatment available, early diagnosis allows for the development of preventive strategies for some severe complications of portal hypertension.

Application of ultrasonography-elastography score to suspect porto-sinusoidal vascular disease in patients with portal vein thrombosis

BACKGROUND

Porto-sinusoidal vascular disease (PSVD) and portal vein thrombosis (PVT) are causes of portal hypertension characterized respectively by an intrahepatic and a pre-hepatic obstacle to the flow in the portal system. As PVT may be a consequence of PSVD, in PVT patients at presentation, a pre-existing PSVD should be suspected. In these patients the identification of an underlying PSVD would have relevant implication regarding follow-up and therapeutic management, but it could be challenging. In this setting ultrasonography may be valuable in differential diagnosis. The aim of the study was to use ultrasonography to identify parameters to discriminate between PSVD and "pure" PVT and then to suspect PVT secondary to a pre-existing PSVD.

METHODS

Fifty-three patients with histologically proven PSVD and forty-eight patients affected by chronic PVT were enrolled and submitted to abdominal ultrasonography with elastography by acoustic radiation force impulse (ARFI).

RESULTS

ARFI was higher and superior mesenteric vein (SMV) diameter was wider in PSVD patients than in PVT patients. Thus, a prognostic score was obtained as linear combinations of the two parameters with a good discrimination capacity between PSVD and PVT (the area under the curve = 0.780; 95% confidence interval: 0.690-0.869).

CONCLUSIONS

A score based on ARFI and SMV diameter may be useful to suspect an underlying PSVD in patients with PVT and to identify a subgroup of patients to be submitted to liver biopsy.

Common variable immunodeficiency disorder-related liver disease is common and results in portal hypertension and an increased risk of death

BACKGROUND

Common variable immunodeficiency disorder (CVID) manifests with recurrent infections and inflammatory complications, including liver disease. We report the clinical features, natural history, and outcomes of patients with CVID-related liver disease (CVID-rLD) from a tertiary immunology and hepatology center.

METHODS

Two hundred eighteen patients were identified; CVID-rLD was defined by persistently abnormal liver function tests or evidence of chronic liver disease (CLD) or portal hypertension (PHTN) by radiological or endoscopic investigation, after exclusion of other causes. Patients with CVID-rLD were investigated and managed following a joint pathway between immunology and hepatology services. Data, including clinical parameters, investigations, and outcomes, were retrospectively collected.

RESULTS

A total of 91/218 (42%) patients had evidence of CVID-rLD, and 40/91 (44%) had PHTN. Patients with CVID-rLD were more likely to have other noninfectious complications of CVID (85/91, 93.4% vs. 75/127, 59.1%, p<0.001) including interstitial lung disease, gut disease, and autoimmune cytopenias. Nodular regenerative hyperplasia (NRH) was identified in 63.8% of liver biopsies, and fibrosis in 95.3%. Liver stiffness measurements (LSMs) were frequently elevated (median 9.95 kPa), and elevated LSM was associated with PHTN. All-cause mortality was higher in those with CVID-rLD (24/91, 26.4% vs. 14/127, 11%, p=0.003), which was the only organ complication associated with mortality (HR 2.24, 1.06-4.74, p=0.04). Factors predicting mortality in CVID-rLD included PHTN, increasing fibrosis, and LSM.

CONCLUSIONS

Liver disease is a common complication of CVID as part of complex, multi-organ involvement and is associated with high rates of PHTN and an increased hazard of mortality.

Portal hypertension in common variable immunodeficiency disorders - a single center analysis on clinical and immunological parameter in 196 patients

Background

Liver manifestations and in particular portal hypertension (PH) contribute significantly to morbidity and mortality of patients with common variable immunodeficiency disorders (CVID). Screening strategies and early detection are limited due to the lack of specific diagnostic tools.

Methods

We evaluated clinical, immunological, histological, and imaging parameters in CVID patients with clinical manifestation of portal hypertension (CVID+PH).

Results

Portal hypertension was present in 5.6% of CVID patients and was associated with high clinical burden and increased mortality (18%). Longitudinal data on clinical and immunological parameters in patients before and during clinically manifest portal hypertension revealed a growing splenomegaly and increasing gamma-glutamyl transferase (GGT) and soluble interleukin 2 receptor (SIL-2R) levels with decreasing platelets over time. While ultrasound of the liver failed to detect signs of portal hypertension in most affected patients, transient elastography was elevated in all patients. All CVID+PH patients had reduced naïve CD45RA+CD4+ T-cells (mean of 6,2%). The frequency of severe B-lymphocytopenia (Euroclass B-) was higher in CVID+PH patients. The main histological findings included lymphocytic infiltration, nodular regenerative hyperplasia-like changes (NRH-LC), and porto(-septal) fibrosis.

Conclusion

CVID patients with lower naïve CD45RA+CD4+ T-cells or severely reduced B-cells might be at higher risk for portal hypertension. The combination of biochemical (increasing sIL-2R, GGT, and decreasing platelets) and imaging parameters (increasing splenomegaly) should raise suspicion of the beginning of portal hypertension.

Molecular Mechanisms Underlying Vascular Liver Diseases: Focus on Thrombosis

Vascular liver disorders (VLDs) comprise a wide spectrum of clinical-pathological entities that primarily affect the hepatic vascular system of both cirrhotic and non-cirrhotic patients. VLDs more frequently involve the portal and the hepatic veins, as well as liver sinusoids, resulting in an imbalance of liver homeostasis with serious consequences, such as the development of portal hypertension and liver fibrosis. Surprisingly, many VLDs are characterized by a prothrombotic phenotype. The molecular mechanisms that cause thrombosis in VLD are only partially explained by the alteration in the Virchow's triad (hypercoagulability, blood stasis, and endothelial damage) and nowadays their pathogenesis is incompletely described and understood. Studies about this topic have been hampered by the low incidence of VLDs in the general population and by the absence of suitable animal models. Recently, the role of coagulation imbalance in liver disease has been postulated as one of the main mechanisms linked to fibrogenesis, so a novel interest in vascular alterations of the liver has been renewed. This review provides a detailed analysis of the current knowledge of molecular mechanisms of VLD. We also focus on the promising role of anticoagulation as a strategy to prevent liver complications and to improve the outcome of these patients.

Portal vein thrombosis, hepatic decompensation, and survival in patients with porto-sinusoidal vascular disease and portal hypertension

BACKGROUND

Porto-sinusoidal vascular disease (PSVD) is a novel nomenclature to describe non-cirrhotic portal hypertension and characteristic histology without portal vein thrombosis (PVT). It is a more inclusive definition than the previously well-recognized entity idiopathic non-cirrhotic portal hypertension. There is a paucity of data on PSVD patients.

METHODS

A total of 33 patients diagnosed with PSVD and portal hypertension (PH) between 2005 and 2021 were included. Data were retrieved from electronic medical record system and analyzed.

RESULTS

Of the 33 patients, 6 (18%) occurred in post-transplant allograft liver. After a median follow-up of 96 months (interquartile range, IQR [52, 139]), 14 deaths occurred (42%), 4 directly related to decompensated liver disease. The Kaplan-Meier survival estimates at 1, 5, and 10 years were 94%, 87% and 58%. PVT occurred in 10 patients (30%). The Nelson-Aalen cumulative risk estimate for PVT at 1, 5 and 10 years were 16%, 25% and 48%. The median model for end-stage liver disease and Child-Pugh score at initial presentation were 8 (IQR [7-12]) and 5 [5-6], and increased to 13 [8, 18] and 7 [5, 8], respectively, at the end of follow-up. Of the 11 patients who presented with splenomegaly and no specific sign of PH, 7 (64%) developed varices and 3 (27%) ascites at a median follow-up of 100 months.

CONCLUSIONS

PSVD with PH is not a benign entity. Mortality, PVT and hepatic decompensation are common. Patients with PSVD must be closely monitored, including those who only have non-specific clinical signs (e.g., splenomegaly) of PH.

Tip of the iceberg: A comprehensive review of liver disease in Inborn errors of immunity

Inborn errors of immunity (IEIs) consist of numerous rare, inherited defects of the immune system that affect about 500,000 people in the United States. As advancements in diagnosis through genetic testing and treatment with targeted immunotherapy and bone marrow transplant emerge, increasing numbers of patients survive into adulthood posing fresh clinical challenges. A large spectrum of hepatobiliary diseases now present in those with immunodeficiency diseases, leading to morbidity and mortality in this population. Awareness of these hepatobiliary diseases has lagged the improved management of the underlying disorders, leading to missed opportunities to improve clinical outcomes. This review article provides a detailed description of specific liver diseases occurring in various inborn errors of immunity. A generalized approach to diagnosis and management of hepatic complications is provided, and collaboration with hepatologists, immunologists, and pathologists is emphasized as a requirement for optimizing management and outcomes.

Liver disease accompanied by enteropathy in common variable immunodeficiency: Common pathophysiological mechanisms

Common variable immunodeficiency (CVID) is one of the inborn errors of immunity that have the greatest clinical impact. Rates of morbidity and mortality are higher in patients with CVID who develop liver disease than in those who do not. The main liver disorder in CVID is nodular regenerative hyperplasia (NRH), the cause of which remains unclear and for which there is as yet no treatment. The etiology of liver disease in CVID is determined by analyzing the liver injury and the associated conditions. The objective of this study was to compare CVID patients with and without liver–spleen axis abnormalities in terms of clinical characteristics, as well as to analyze liver and duodenal biopsies from those with portal hypertension (PH), to elucidate the pathophysiology of liver injury. Patients were divided into three groups: Those with liver disease/PH, those with isolated splenomegaly, and those without liver–spleen axis abnormalities. Clinical and biochemical data were collected. Among 141 CVID patients, 46 (32.6%) had liver disease/PH; 27 (19.1%) had isolated splenomegaly; and 68 (48.2%) had no liver–spleen axis abnormalities. Among the liver disease/PH group, patients, even those with mild or no biochemical changes, had clinical manifestations of PH, mainly splenomegaly, thrombocytopenia, and esophageal varices. Duodenal celiac pattern was found to correlate with PH (p < 0.001). We identified NRH in the livers of all patients with PH (n = 11). Lymphocytic infiltration into the duodenal mucosa also correlated with PH. Electron microscopy of liver biopsy specimens showed varying degrees of lymphocytic infiltration and hepatocyte degeneration, which is a probable mechanism of lymphocyte-mediated cytotoxicity against hepatocytes and enterocytes. In comparison with the CVID patients without PH, those with PH were more likely to have lymphadenopathy (p < 0.001), elevated β₂-microglobulin (p < 0.001), low B-lymphocyte counts (p < 0.05), and low natural killer-lymphocyte counts (p < 0.05). In CVID patients, liver disease/PH is common and regular imaging follow-up is necessary. These patients have a distinct immunological phenotype that may predispose to liver and duodenal injury from lymphocyte-mediated cytotoxicity. Further studies could elucidate the cause of this immune-mediated mechanism and its treatment options.

Severe Ascites in Common Variable Immunodeficiency

Liver disease is one of the possible clinical manifestations of common variable immunodeficiency and can range from mild hepatomegaly and persistent elevation of liver enzymes to cirrhosis, portal hypertension, and nodular regenerative hyperplasia. The last one is the most common histologic presentation of liver involvement by common variable immunodeficiency and its clinical spectrum can range from asymptomatic to cholestasis, liver cirrhosis, or idiopathic non-cirrhotic portal hypertension, with the severe manifestations being less recognised. We present a case of a 48-year-old woman who was referred for an internal medicine consultation for evaluation of rapidly progressing (span of three months) large-volume ascites and marked asthenia. The patient had a past medical history of common variable immunodeficiency and a recent episode of severe haemolytic anaemia. Peritoneal fluid analyses identified portal hypertension as the cause of the ascites. Abdominal Doppler ultrasound and contrasted abdominal computed tomography confirmed the presence of permeable hepatic and portal veins. Liver biopsy revealed regenerative nodular hyperplasia without cirrhosis. A diagnosis of idiopathic non-cirrhotic portal hypertension secondary to common variable immunodeficiency was made. Treatment was adjusted with considerable improvement in ascites. In conclusion, idiopathic non-cirrhotic portal hypertension is a possible and often overlooked complication in patients with common variable immunodeficiency and is an exclusion diagnosis that requires a high level of suspicion, especially in patients with ascites.

Living donor liver transplantation for idiopathic portal hypertension with focal nodular hyperplasia

The patient was a 61-year-old woman with a history of diabetes mellitus who had undergone ileocecal resection for ascending colon carcinoma 5 years earlier, followed by a postoperative adjuvant chemotherapy with XELOX (capecitabine + oxaliplatin). During follow-up, the liver gradually atrophied, and radiological imaging showed suspicious findings of 20 × 14 mm hepatocellular carcinoma (HCC) in the right lobe of the liver. The patient also underwent endoscopic variceal ligation for the esophageal varices. She was referred to our hospital for living donor liver transplantation (LDLT) due to decompensated liver cirrhosis with HCC. The patient did not have hepatitis B or C, and history of alcohol, suggesting that her liver cirrhosis was caused by a non-alcoholic steatohepatitis. The Child-Pugh score was 10 points (class C) and the Model for End-Stage Liver Disease (MELD) score was 8 points. The possibility of HCC could not be ruled out, and LDLT was performed. Postoperative pathological examination revealed idiopathic portal hypertension (IPH), and the mass lesion was diagnosed as focal nodular hyperplasia (FNH). The postoperative course was uneventful and the patient was discharged on postoperative day 14. This is the first case of liver transplantation for IPH with FNH.

Nodular regenerative hyperplasia in X-linked agammaglobulinemia: An underestimated and severe complication

BACKGROUND

Late-onset complications in X-linked agammaglobulinemia (XLA) are increasingly recognized. Nodular regenerative hyperplasia (NRH) has been reported in primary immunodeficiency but data in XLA are limited.

OBJECTIVES

This study sought to describe NRH prevalence, associated features, and impact in patients with XLA.

METHODS

Medical records of all patients with XLA referred to the National Institutes of Health between October 1994 and June 2019 were reviewed. Liver biopsies were performed when clinically indicated. Patients were stratified into NRH+ or NRH- groups, according to their NRH biopsy status. Fisher exact test and Mann-Whitney test were used for statistical comparisons.

RESULTS

Records of 21 patients with XLA were reviewed, with a cumulative follow-up of 129 patient-years. Eight patients underwent ≥1 liver biopsy of whom 6 (29% of the National Institutes of Health XLA cohort) were NRH+. The median age at NRH diagnosis was 20 years (range, 17-31). Among patients who had liver biopsies, alkaline phosphatase levels were only increased in patients who were NRH+ (P = .04). Persistently low platelet count (<100,000 per μL for >6 months), mildly to highly elevated hepatic venous pressure gradient and either hepatomegaly and/or splenomegaly were present in all patients who were NRH+. In opposition, persistently low platelet counts were not seen in patients who were NRH-, and hepatosplenomegaly was observed in only 1 patient who was NRH-. Hepatic venous pressure gradient was normal in the only patient tested who was NRH-. All-cause mortality was higher among patients who were NRH+ (5 of 6, 83%) than in the rest of the cohort (1 of 15, 7% among patients who were NRH- and who were classified as unknown; P = .002).

CONCLUSIONS

NRH is an underreported, frequent, and severe complication in XLA, which is associated with increased morbidity and mortality.

Idiopathic Non-Cirrhotic Portal Hypertension and Porto-Sinusoidal Vascular Disease: Review of Current Data

Idiopathic non-cirrhotic portal hypertension (INCPH) is a clinicopathologic disease entity characterized by the presence of clinical signs and symptoms of portal hypertension (PH) in the absence of liver cirrhosis or known risk factors accountable for PH. Multiple hematologic, immune-related, infectious, hereditary and metabolic risk factors have been associated with this disorder. Still, the exact etiopathogenesis is largely unknown. The recently proposed porto-sinusoidal vascular disease (PSVD) scheme broadens the spectrum of the disease by also including patients without clinical PH who are found to have similar histopathologic findings on core liver biopsies. Three histomorphologic lesions have been identified as specific for PSVD to include obliterative portal venopathy, nodular regenerative hyperplasia and incomplete septal cirrhosis/fibrosis. However, these findings are often subtle, under-recognized and subjective with low interobserver agreement among pathologists. Additionally, the natural history of the subclinical forms of the disease remains unexplored. The clinical course is more favorable compared to cirrhosis patients, especially in the absence of clinical PH or liver dysfunction. There are no universally accepted guidelines in regard to diagnosis and treatment of INCPH/PSVD. Hence, this review emphasizes the need to raise awareness of this entity by highlighting its complex pathophysiology and clinicopathologic associations. Lastly, formulation of standardized diagnostic criteria with clinical validation is necessary to avoid misclassifying vascular diseases of the liver and to develop and implement targeted therapeutic strategies.

Porto-sinusoidal vascular disease: proposal and description of a novel entity

Portal hypertension in the absence of portal vein thrombosis and without cirrhosis, but with mild or moderate alterations of liver histology (eg, obliterative venopathy, nodular regenerative hyperplasia, or incomplete septal cirrhosis) is being increasingly recognised. Owing to the heterogeneity of causes and histological findings, a substantial number of terms have been used to describe such idiopathic non-cirrhotic portal hypertension. Patients with the same clinical and histological features exist, but without portal hypertension at the time of diagnosis. Therefore, improved criteria are needed to define this form of liver disease. Here, we propose the term porto-sinusoidal vascular disease, since all lesions found involve the portal venules or sinusoids. The definition of this entity is based on the characteristic absence of cirrhosis with or without signs of portal hypertension or histological lesions. The presence of known causes of liver disease does not rule out porto-sinusoidal vascular disease, but specific causes of vascular liver disease are excluded from its definition. The diagnosis of porto-sinusoidal vascular disease is based on liver biopsy and might include signs specific for portal hypertension with normal or mildly elevated liver stiffness values and no complete portal vein thrombosis. We provide simple diagnostic criteria, because agreement on a uniform nomenclature is an essential requirement for future collaborative studies.

Heterogeneity of Liver Disease in Common Variable Immunodeficiency Disorders

Common variable immunodeficiency (CVID) is the most frequent primary immunodeficiency (PID) in adulthood and is characterized by severe reduction of immunoglobulin serum levels and impaired antibody production in response to vaccines and pathogens. Beyond the susceptibility to infections, CVID encompasses a wide spectrum of clinical manifestations related to a complex immune dysregulation that also affects liver. Although about 50% CVID patients present persistently deranged liver function, burden, and nature of liver involvement have not been systematically investigated in most cohort studies published in the last decades. Therefore, the prevalence of liver disease in CVID widely varies depending on the study design and the sampling criteria. This review seeks to summarize the evidence about the most relevant causes of liver involvement in CVID, including nodular regenerative hyperplasia (NRH), infections and malignancies. We also describe the clinical features of liver disease in some monogenic forms of PID included in the clinical spectrum of CVID as ICOS, NFKB1, NFKB2, CTLA-4, PI3Kδ pathway, ADA2, and IL21-R genetic defects. Finally, we discuss the clinical applications of the various diagnostic tools and the possible therapeutic approaches for the management of liver involvement in the context of CVID.

Clinical features of idiopathic portal hypertension in China: A retrospective study of 338 patients and literature review

BACKGROUND AND AIM

Idiopathic portal hypertension (IPH) refers to a relatively rare condition characterized by intrahepatic portal hypertension in the absence of underlying disease such as liver cirrhosis.

METHODS

We retrospectively reviewed 338 patients with IPH that were diagnosed at the pathological consultation center of our hospital.

RESULTS

The ratio of male to female patients was 1:1. Mean age at onset was 35.1 ± 16.5 years; male patients on average were 12 years younger than female patients at onset. The median duration from onset to IPH diagnosis was 12 months. In 50 patients, medication use may have been an etiological factor. The most common clinical manifestations were splenomegaly (91.3%) and hypersplenism (68.9%); 57.0% patients presented varicosis, while 25.1% patients had a history of variceal bleeding. Nodular regenerative hyperplasia was found in 22.2% liver biopsies. Among patients for whom laboratory data were available, 65.0%, 50.3%, and 71.4% patients presented leukopenia, anemia, and thrombocytopenia due to hypersplenism. Liver function was mostly in the compensated stage. Female patients showed worse leukopenia and anemia, while male patients were more likely to have abnormal serum transaminase and bilirubin levels. Sixty-seven patients received surgical or interventional treatment.

CONCLUSIONS

High-quality liver biopsy, detailed clinical information, and expert pathologist are necessary for diagnosis of IPH. IPH can occur concurrently with other liver disease such as hepatitis and drug-induced liver injury. Medication appears to be an important etiological factor for IPH in China. Management approach was largely focused on treatment of portal hypertension and its complications.

Idiopathic Portal Hypertension

Idiopathic portal hypertension (IPH) is a rare disorder characterized by clinical portal hypertension in the absence of a recognizable cause such as cirrhosis. Laboratory tests often reveal a preserved liver function with anemia, leukopenia, and thrombocytopenia due to splenomegaly. Imaging studies reveal signs of portal hypertension, whereas liver stiffness and portal pressure values are usually normal or slightly elevated. Liver biopsy is considered mandatory in order to rule out other causes of portal hypertension, mainly cirrhosis. Liver histology may only show subtle or mild changes, and the definite diagnosis of IPH often requires an expert pathologist and a high-quality specimen. The most frequent clinical presentation is variceal bleeding. Ascites is rarely observed initially, although it may occasionally appear during follow-up. Typical histological findings associated with IPH have been described in patients without portal hypertension, probably representing early stages of the disease. Although the pathophysiology of this entity remains largely unknown, it is frequently associated with underlying immunological disorders, bacterial infections, trace metal poisoning, medications, liver circulatory disturbances, and thrombotic events. The long-term prognosis of patients with IPH, where ascites and the underlying condition are important prognostic factors, is better than in patients with cirrhosis. Treatments that modify the natural history of the disease remain an unmet need, and management of IPH is frequently restricted to control of portal hypertension-related complications.

Idiopathic portal hypertension and extrahepatic portal venous obstruction

BACKGROUND

Idiopathic portal hypertension (IPH) and extrahepatic portal venous obstruction (EHPVO) are non-cirrhotic vascular causes of portal hypertension (PHT). Variceal bleed and splenomegaly are the commonest presentations.

AIM

The present review is intended to provide the existing literature on etiopathogenesis, clinical profile, diagnosis, natural history and management of IPH and EHPVO.

RESULTS

IPH and EHPVO are both characterized by normal hepatic venous pressure gradient, moderate to massive splenomegaly with preserved liver synthetic functions. While the level of block in IPH is presinusoidal, in EHPVO it is at prehepatic level. Infections, autoimmunity, drugs, immunodeficiency and prothrombotic states are possible etiological agents in IPH. Contrastingly in EHPVO, prothrombotic disorders and local factors around the portal vein are the incriminating factors. Diagnosis is often clinical, supported by simple radiological tools. Natural history is defined by episodes of variceal bleed and symptoms related to enlarged spleen. Growth failure, portal biliopathy and minimal hepatic encephalopathy are additional concerns in EHPVO. Long-term survival is reasonably good with endoscopic surveillance; however, parenchymal extinction leading to decompensation is seen in a minority of patients in both the disorders. Surgical shunts revert the complications secondary to PHT. Meso-Rex shunt has become the standard surgery in children with EHPVO.

CONCLUSION

This review gives a detailed summary of these two vascular conditions of liver-IPH and EHPVO. Further research is needed to understand the pathogenesis and natural history of these disorders.

Idiopathic noncirrhotic portal hypertension: current perspectives

The term idiopathic noncirrhotic portal hypertension (INCPH) has been recently proposed to replace terms, such as hepatoportal sclerosis, idiopathic portal hypertension, incomplete septal cirrhosis, and nodular regenerative hyperplasia, used to describe patients with a hepatic presinusoidal cause of portal hypertension of unknown etiology, characterized by features of portal hypertension (esophageal varices, nonmalignant ascites, porto-venous collaterals), splenomegaly, patent portal, and hepatic veins and no clinical and histological signs of cirrhosis. Physicians should learn to look for this condition in a number of clinical settings, including cryptogenic cirrhosis, a disease known to be associated with INCPH, drug administration, and even chronic alterations in liver function tests. Once INCPH is clinically suspected, liver histology becomes mandatory for the correct diagnosis. However, pathologists should be familiar with the histological features of INCPH, especially in cases in which histology is not only requested to exclude liver cirrhosis.

Immunoglobulin-induced hemolysis, splenomegaly and inflammation in patients with antibody deficiencies

IgG replacement for primary antibody deficiencies is a safe treatment administered to prevent recurrent infections and reduce mortality. Recently, several reports described acute hemolytic episodes following IgG administration due to a passive transfer of blood group alloantibodies, including anti-A, anti-B, as well as anti-Rh antibodies. Here, we reviewed and discussed the consequences of passively transferred RBCs antibodies. The chronic passive transfer of alloantibodies might also cause a subclinical condition due to a compensated extravascular chronic hemolysis with poorly understood consequences. This phenomenon might possibly represent an unrecognized cause of splenomegaly and might contribute to inflammation in patients with primary antibody deficiencies.

Comprehensive Screening of Gene Function and Networks by DNA Microarray Analysis in Japanese Patients with Idiopathic Portal Hypertension

The functions of genes involved in idiopathic portal hypertension (IPH) remain unidentified. The present study was undertaken to identify the functions of genes expressed in blood samples from patients with IPH through comprehensive analysis of gene expression using DNA microarrays. The data were compared with data from healthy individuals to explore the functions of genes showing increased or decreased expression in patients with IPH. In cluster analysis, no dominant probe group was shown to differ between patients with IPH and healthy controls. In functional annotation analysis using the Database for Annotation Visualization and Integrated Discovery tool, clusters showing dysfunction in patients with IPH involved gene terms related to the immune system. Analysis using network-based pathways revealed decreased expression of adenosine deaminase, ectonucleoside triphosphate diphosphohydrolase 4, ATP-binding cassette, subfamily C, member 1, transforming growth factor-β, and prostaglandin E receptor 2; increased expression of cytochrome P450, family 4, subfamily F, polypeptide 3, and glutathione peroxidase 3; and abnormalities in the immune system, nucleic acid metabolism, arachidonic acid/leukotriene pathways, and biological processes. These results suggested that IPH involved compromised function of immunocompetent cells and that such dysfunction may be associated with abnormalities in nucleic acid metabolism and arachidonic acid/leukotriene-related synthesis/metabolism.