Intrasinusoidal cytotoxic CD8+ T cells in nodular regenerative hyperplasia of the liver

Common variable immunodeficiency disorder (CVID)-related liver disease: assessment of the main histological aspects using novel semiquantitative scoring systems, image analysis and correlation with clinical parameters of liver stiffness and portal hypertension

AIMS

We aimed to investigate the relationship between T-cell-mediated sinusoidal injury, nodular regenerative hyperplasia like changes (NRH-LC) and fibrosis, clinical measures of fibrosis and portal hypertension, and progression rate in common variable immunodeficiency disorder (CVID)-related liver disease.

METHODS

This is a retrospective single-centre study. Liver biopsies from CVID patients with liver disease were reviewed to assess for NRH-LC, fibrosis and elastosis, including collagen and elastin proportionate areas. CD3 positive T-cells infiltration and sinusoidal endothelial changes by CD34 expression were quantified by image analysis and a semiquantitative method, respectively. These findings were correlated with liver stiffness measurements (LSM) and hepatic venous pressure gradient (HVPG).

RESULTS

NRH-LC and pericellular elastosis were present in most biopsies (32/40 and 38/40, respectively). All biopsies showed fibrosis, which was limited to pericellular in 21/40 (52.5%) and included bridging fibrous septa in 19/40 (47.5%). 28/40 liver biopsies showed enhanced sinusoidal expression of CD34. There were more CD3 positive cells in biopsies with NRH-LC compared with those without. There was no significant correlation between LSM, HVPG and fibrosis/elastosis scores. Five of seven patients with at least two biopsies showed progression in fibrosis stage.

CONCLUSIONS

NRH-LC and fibrosis in CVID patients often coexist along with the presence of sinusoidal endothelial changes and sinusoidal lymphocytic infiltration. Fibrosis progresses over time, and significant fibrosis can be observed in young patients (<30 years old), potentially reflecting a more aggressive form of CVID-related liver disease. Further studies are necessary to investigate the relationship between histological findings, clinical measures of fibrosis and portal hypertension and outcome.

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.

Management of liver disease and portal hypertension in common variable immunodeficiency (CVID)

Patients with common variable immunodeficiency (CVID) frequently develop liver disease and associated complications, which represent an increasingly prevalent unmet medical need. The main hepatic manifestation of CVID is nodular regenerative hyperplasia (NRH), resulting in non-cirrhotic portal hypertension (NCPH). Liver disease is often underdiagnosed, leading to poor outcomes and decreased survival. The increasing numbers of patients with CVID who are diagnosed late with progressive liver disease underscores the importance of appropriate clinical management and treatment of liver complications. At the same time, specific guidelines for the clinical management of CVID-related liver disease are still lacking. Here, we review the epidemiology of CVID-related liver disease, reveal new insights into NRH and NCPH biology and highlight recently uncovered opportunities for NCPH diagnostics in CVID. Finally, we focus on current management of liver disease, portal hypertension and its complications - the key challenge in patients with CVID. Specifically, we review recent data regarding the role of transjugular intrahepatic portosystemic shunt and liver transplantation in clinical management. The role for anticoagulants and immunosuppressants targeting the pathogenesis of NRH will also be discussed. We propose an updated algorithm for the diagnostic work-up and treatment of NCPH in CVID. Finally, we consider future needs and therapeutic opportunities for CVID-related liver disease.

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.

Evidence for Alloimmune Sinusoidal Injury in De Novo Nodular Regenerative Hyperplasia After Liver Transplantation

Posttransplant nodular regenerative hyperplasia (NRH) mostly remains unexplained. Microvascular injury due to antibody-mediated rejection (AMR) is suspected, but lack of donor specific antibody (DSA) testing makes it difficult to prove. Centered around a 1-year period of routine DSA testing, concomitant protocol, and indicated posttransplant liver biopsies (LB), recipients with NRH (n = 18) were compared with a matched control group (n = 36). All index, previous, and subsequent LB were reviewed. Both groups were similar in terms of demographics, timing of index LB, and DSA. In the index LB, the NRH group had higher sinusoidal C4d positivity (p = 0.029) and perisinusoidal fibrosis (p = 0.034), both independently associated with NRH (p = 0.038 and 0.050, respectively). Features of "possible" chronic AMR were detected in 28.5% of the NRH group without a known cause and 0% of the control group (p = 0.009). The NRH group had more preceding indicated LB with increased incidence of rejection and biliary obstruction pattern. In the follow-up histology, overall, sinusoidal and portal C4d positivity, sinusoidal microvasculitis, and perisinusoidal fibrosis were also higher (all p < 0.050). In conclusion, we provide evidence towards the hypothesis that some cases of posttransplant NRH are related to preceding active and persistent AMR. Large multicenter studies with protocol DSA testing are required to confirm.

Clinical manifestations and approach to the management of patients with common variable immunodeficiency and liver disease

Purpose

The clinical spectrum of common variable immunodeficiency (CVID) includes predisposition to infections, autoimmune/inflammatory complications and malignancy. Liver disease is developed by a proportion of patients with CVID, but limited evidence is available about its prevalence, pathogenesis and prognostic outcome. This lack of evidence leads to the absence of guidelines in clinical practice. In this study, we aimed at defining the characteristics, course and management of this CVID complication in Spain.

Methods

Spanish reference centers were invited to complete a cross-sectional survey. Thirty-eight patients with CVID-related liver disease from different hospitals were evaluated by a retrospective clinical course review.

Results

In this cohort, abnormal liver function and thrombocytopenia were found in most of the patients (95% and 79% respectively), in keeping with the higher incidence of abnormal liver imaging and splenomegaly. The most common histological findings included nodular regenerative hyperplasia (NRH) and lymphocytic infiltration, which have been associated with portal hypertension (PHTN) leading to a poorer prognosis. Autoimmune/inflammatory complications occurred in 82% of the CVID patients that developed liver disease and 52% of the patients treated with immunomodulators showed a reduction in the liver function tests' abnormalities during treatment. Among the experts that conducted the survey, there was 80% or more consensus that the workup of CVID-related liver disease requires liver profile, abdominal ultrasound and transient elastography. The majority agreed that liver biopsy should be essential for diagnosis. There was 94% consensus that endoscopic studies should be performed in the presence of PHTN. However, there was 89% consensus that there is insufficient evidence on the management of these patients.

Conclusion

Liver disease varies in severity and may contribute substantially to morbidity and mortality in patients with CVID. Hence the importance of close follow-up and screening of this CVID complication to prompt early targeted intervention. Further research is needed to evaluate the pathophysiology of liver disease in patients with CVID to identify personalized treatment options. This study emphasizes the urgent need to develop international guidelines for the diagnosis and management of this CVID complication.

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.

Gut inflammation in CVID: causes and consequences

INTRODUCTION

There is a wide spectrum of noninfectious gastrointestinal pathology, causing considerable morbidity and mortality in CVID, where both etiology and effective therapy are under debate.

AREAS COVERED

This review will focus on the noninfectious inflammation in the GI tract in CVID patients, covering the both the upper and lower GI tract inflammation, including the liver. The controversy of the CVID enteropathy definition and that of gluten-free diet for celiac-like disease in CVID will be discussed. Furthermore, the review will cover the link between GI inflammation and GI cancer. Finally, the role of gut microbiota, IgA, and genetics and its relationship with CVID enteropathy is scrutinized. The authors reviewed literature from PubMed.

EXPERT OPINION

The heterogeneity and the unknown mechanism behind CVID enteropathy, and thereby the lack of effective treatment, is one of the key challenges in the field of CVID. Celiac-like disease in CVID is due to immune dysregulation, and a gluten-free diet is therefore not indicated. Gut microbial dysbiosis and mucosal IgA can initiate systemic and local inflammation and is involved in the immune dysregulation in CVID. Considering the heterogeneity of CVID enteropathy, personalized medicine is probably the future for these patients.

Spectrum of Hepatic Manifestations of Common Variable Immunodeficiency

Common variable immunodeficiency (CVID) has a heterogenous clinical presentation and can be challenging to diagnose. Distinct histologic changes have been linked with CVID in several organ systems, which can help identify the correct diagnosis. In this study we review a cohort of hepatic CVID biopsies, to better define the spectrum of histologic and biochemical alterations. We reviewed 26 liver biopsies from 24 patients with CVID, obtained at 4 institutions between 2010 and 2019. Histologic slides were examined, and pathologic, biochemical, and clinical features were recorded. A control cohort of 21 patients with nodular regenerative hyperplasia (NRH) but lacking CVID was also examined. Liver function tests were frequently abnormal, especially alkaline phosphatase (median: 193 IU/L) and aspartate transaminase (median: 56 U/L), elevated in 23 and 17 of 25 biopsies, respectively. Fifteen patients had CVID involvement of other organs. Histologic features of primary biliary cholangitis were present in 2 patients, with florid duct lesions and prominent bile duct injury, in association with positive antimitochondrial antibodies. Among the other 24 biopsies, mild to moderate portal and lobular inflammation were present in 18 and 17 of 24 biopsies, respectively. Overall, 22 of 24 biopsies showed NRH-like changes. Plasma cell were absent. A distinct pattern of pericellular fibrosis was present in 23 of 26 biopsies overall. Involvement ranged from focal centrizonal fibrosis to bridging fibrosis and was accompanied by increased intrasinusoidal lymphocytes in 13 of 24 biopsies. Pericellular fibrosis was identified in 1 of 21 biopsies in the control cohort. Additional findings included granulomatous inflammation or nonhepatocellular foreign body-type multinucleate giant cells, identified in 4 biopsies. Three of 6 examined biopsies also demonstrated focal hepatocellular copper deposition. Hepatic disease in CVID is often associated with elevated alkaline phosphatase and aspartate transaminase and is characterized histologically by the mild nonspecific portal and lobular hepatitis, absence of plasma cells, NRH-like changes, and less commonly, typical histologic features of primary biliary cholangitis. We have also identified a distinctive pattern of delicate pericellular fibrosis that is a helpful clue to the diagnosis of hepatic disease in CVID, especially when accompanied by NRH-like changes.

Non-cirrhotic portal hypertension in an ankylosing spondylitis patient

Idiopathic non-cirrhotic portal hypertension (INCPH) is a disease with an uncertain etiology consisting of non-cirrhotic portal hypertension and portal pressure increase in the absence of liver cirrhosis. In INCPH, patients exhibit normal liver functions and structures. The factors associated with INCPH include the following: Umbilical/portal pyremia, bacterial diseases, prothrombic states, chronic exposure to arsenic, vinyl chloride monomers, genetic disorders, and autoimmune diseases. Approximately 70% of patients present a history of major variceal bleeding, and treatment relies on the prevention of complications related to portal hypertension. Autoimmune disorders associated with INCPH are mainly systemic sclerosis, systemic lupus erythematosus and rheumatoid arthritis. To the best of our knowledge, a case of ankylosing spondylitis (AS) associated with INCPH has not been reported thus far. Therfore, we report our experience of a patient with AS accompanied by INCPH, who showed perisplenic varices with patent spleno-portal axis and hepatic veins along with no evidence of cirrhosis on liver biopsy, and provide a brief literature review.

Nodular Regenerative Hyperplasia of the Liver: A Rare Vascular Complication in Systemic Sclerosis

Objective.

To investigate nodular regenerative hyperplasia (NRH) as a vascular complication of systemic sclerosis (SSc) with microvasculopathy as a common denominator.

Methods.

Cases of SSc-NRH were identified by systematic literature review and by screening the Zurich cohort. NRH had to be diagnosed by liver biopsy.

Results.

Literature review retrieved 22 cases. In our cohort, 1.4% of patients with SSc were diagnosed with NRH. Most had vasculopathy, were positive for anticentromere antibodies, had elevated alkaline phosphatase and gamma-glutamyl transferase levels, normal liver morphology on ultrasound yet increased stiffness on ultrasound elastography, and had portal hypertension.

Conclusion.

NRH might represent a rare yet potentially life-threatening vascular complication in SSc.

Primary/Congenital Immunodeficiency: 2015 SH/EAHP Workshop Report-Part 5

OBJECTIVES

The 2015 Workshop of the Society for Hematopathology/European Association for Haematopathology aimed to review primary immunodeficiency and related lymphoproliferations.

METHODS

Primary immunodeficiencies were divided into immune dysregulation, DNA repair defects, low immunoglobulins, and combined immunodeficiencies.

RESULTS

Autoimmune lymphoproliferative syndrome (ALPS) is a prototypical immune dysregulation-type immunodeficiency, with defects in T-cell signaling or apoptosis, expansion of T-cell subsets, and predisposition to hemophagocytic lymphohistiocytosis. DNA repair defects directly predispose to malignancy. Low immunoglobulin immunodeficiencies such as common variable immunodeficiency (CVID) have underlying T-cell repertoire abnormalities predisposing to autoimmunity and B-cell lymphoproliferations. The full spectrum of B-cell lymphoproliferative disorders occurs in primary immunodeficiency.

CONCLUSIONS

Lymphoproliferations in primary immunodeficiency mirror those in other immunodeficiency settings, with monomorphic B- and sometimes T lymphoproliferative disorders enriched in DNA repair defects. Distinctive T-cell subset expansions in ALPS, CVID, and related entities can mimic lymphoma, and recognition of double-negative T-cell or cytotoxic T-cell expansions is key to avoid overdiagnosis.

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.

Indolent cytotoxic T cell lymphoproliferation associated with nodular regenerative hyperplasia: a common liver lesion in the context of common variable immunodeficiency disorder

Patients with common variable immunodeficiency disorder (CVID) are subject to lymphoproliferative disorders and predisposed to lymphoma. Some patients may also develop liver lesions. The purpose of this study was to define clinical and histopathological features of patients with CVID presenting with liver lesions suspicious of lymphoma. Four CVID cases corresponding to these criteria were retrieved from our files. Liver biopsy specimens were subjected to morphologic, immunophenotypic and molecular analysis. All patients presented with hepatosplenomegaly and two furthermore with lymphadenopathy. The clinical working diagnosis in the four cases was lymphoma. All liver biopsies revealed nodular regenerative hyperplasia (NRH), associated with mild to marked sinusoid lymphocytic infiltrate consisting of "activated" cytotoxic T cells (CD8+, Tia1+, granzyme B+, TCRβF1+, CD56-). EBER was negative in all cases. T cell clonality was found in one of the two interpretable cases. All patients had an indolent course and clinical symptoms regressed with immunoglobulin replacement. This study suggests that indolent proliferation in the liver sinusoid of cytotoxic T cell associated with NRH is a specific liver lesion in the context of CVID. In CVID patients clinically suspected of lymphoma, pathologists should avoid a misdiagnosis of aggressive T cell lymphoma with a risk of over treatment.

Idiopathic non-cirrhotic portal hypertension: a review

Idiopathic non-cirrhotic portal hypertension (INCPH) is a rare disease characterized of intrahepatic portal hypertension in the absence of cirrhosis or other causes of liver disease and splanchnic venous thrombosis. The etiology of INCPH can be classified in five categories: 1) immunological disorders (i.e. association with common variable immunodeficiency syndrome, connective tissue diseases, Crohn’s disease, etc.), 2) chronic infections, 3) exposure to medications or toxins (e.g. azathioprine, 6- thioguanine, arsenic), 4) genetic predisposition (i.e. familial aggregation and association with Adams-Oliver syndrome and Turner disease) and 5) prothrombotic conditions (e.g. inherited thrombophilias myeloproliferative neoplasm antiphospholipid syndrome). Roughly, INCPH diagnosis is based on clinical criteria and the formal exclusion of any other causes of portal hypertension. A formal diagnosis is based on the following criteria: 1) presence of unequivocal signs of portal hypertension, 2) absence of cirrhosis, advanced fibrosis or other causes of chronic liver diseases, and 3) absence of thrombosis of the hepatic veins or of the portal vein at imaging. Patients with INCPH usually present with signs or symptoms of portal hypertension such as gastro-esophageal varices, variceal bleeding or splenomegaly. Ascites and/or liver failure can occur in the context of precipitating factors. The development of portal vein thrombosis is common. Survival is manly limited by concomitant disorders. Currently, treatment of INCPH relies on the prevention of complications related to portal hypertension, following current guidelines of cirrhotic portal hypertension. No treatment has been studied aimed to modify the natural history of the disease. Anticoagulation therapy can be considered in patients who develop portal vein thrombosis.

Portal hypertension as immune mediate disease

CONTEXT

Portal Hypertension (PH) is a progressive complication due to chronic liver disease. In addition to pathophysiologic changes in the micro-circulation, in PH are established fibrous tissue (periportal fibrous septal) and regenerative hyperplastic nodules (from micro- to macro-nodules) promoting hepatic architectural distortion.

EVIDENCE ACQUISITION

A literature search of electronic databases was undertaken for the major studies published from 1981 to today. The databases searched were: PubMed, EMBASE, Orphanet, Midline and Cochrane Library. We used the keywords: "portal hypertension, children, immune system, endocrine system, liver fibrosis".

RESULTS

It is believed that PH results from three "phenotype": ischemia-reperfusion, involving nervous system (NS); edema and oxidative damage, involving immune system; inflammation and angiogenesis, involving endocrine system. However, its exact cause still underdiagnosed and unknown.

CONCLUSIONS

PH is a dynamic and potentially reversible process. Researchers have tried to demonstrate mechanisms underlying PH and its related-complications. This review focuses on the current knowledge regarding the pathogenesis, and immune, endocrine-metabolic factors of disease. The strong positive association between immune system and development of PH could be efficient to identify non-invasive markers of disease, to modify prognosis of PH, and to development and application of specific and individual anti-inflammatory therapy.

Nodular regenerative hyperplasia in common variable immunodeficiency

PURPOSE

Patients with Common Variable Immunodeficiency (CVID) are subject to the development of a liver disease syndrome known as nodular regenerative hyperplasia (NRH). The purpose of this study was to define the characteristics and course of this complication of CVID.

METHODS

CVID patients were evaluated by retrospective and prospective clinical course review. Liver biopsy specimens were evaluated for evidence of NRH and studied via RT-PCR for cytokine analysis.

RESULTS

NRH in our CVID patient population occurred in approximately 5 % of the 261 patients in our total CVID study group, initially presenting in most cases with an elevated alkaline phosphatase level. While in some patients the disease remained static, in a larger proportion a more severe disease developed characterized by portal hypertension, the latter leading to hypersplenism with neutropenia and thrombocytopenia and, in some cases, to ascites. In addition, a substantial proportion of patients either developed or presented initially with an autoimmune hepatitis-like (AIH-like) liver disease that resulted in severe liver dysfunction and, in most cases to death due to infections. The liver histologic findings in these AIH-like patients were characterized by underlying NRH pattern with superimposed interface hepatitis, lymphocytic infiltration and fibrosis. Immunologic studies of biopsies of NRH patients demonstrated the presence of infiltrating T cells producing IFN-γ, suggesting that the NRH is due to an autoimmune process.

CONCLUSION

Overall, these studies provide evidence that NRH may not be benign but, can be a severe and potentially fatal disease complication of CVID that merits close monitoring and intervention.

Portal hypertension from nodular regenerative hyperplasia of the liver treated with distal splenorenal shunt

Portal hypertension (PH) is a devastating sequelae of several pathologic entities, with alcoholic cirrhosis being the most common cause in the western world and endemic schistosomiasis worldwide. A much less common aetiology of non-cirrhotic PH is nodular regenerative hyperplasia (NRH) of the liver. The hallmark of NRH is a benign remodeling of the hepatic parenchyma into regenerative nodules in the absence of fibrosis (1). A Warren-Zeppa Distal Splenorenal Shunt (DSRS) was performed in a young patient with NRH of the liver to alleviate PH. This procedure was chosen due to its low postoperative rates of hepatic insufficiency and high durability.

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.

Intracellular versus extracellular granzyme B in immunity and disease: challenging the dogma

The cytotoxic granzyme B (GrB)/perforin pathway has been traditionally viewed as a primary mechanism that is used by cytotoxic lymphocytes to eliminate allogeneic, virally infected and/or transformed cells. Although originally proposed to have intracellular and extracellular functions, upon the discovery that perforin, in combination with GrB, could induce apoptosis, other potential functions for this protease were, for the most part, disregarded. As there are 5 granzymes in humans and 11 granzymes in mice, many studies used perforin knockout mice as an initial screen to evaluate the role of granzymes in disease. However, in recent years, emerging clinical and biochemical evidence has shown that the latter approach may have overlooked a critical perforin-independent, pathogenic role for these proteases in disease. This review focuses on GrB, the most characterized of the granzyme family, in disease. Long known to be a pro-apoptotic protease expressed by cytotoxic lymphocytes and natural killer cells, it is now accepted that GrB can be expressed in other cell types of immune and nonimmune origin. To the latter, an emerging immune-independent role for GrB has been forwarded due to recent discoveries that GrB may be expressed in nonimmune cells such as smooth muscle cells, keratinocytes, and chondrocytes in certain disease states. Given that GrB retains its activity in the blood, can cleave extracellular matrix, and its levels are often elevated in chronic inflammatory diseases, this protease may be an important contributor to certain pathologies. The implications of sustained elevations of intracellular and extracellular GrB in chronic vascular, dermatological, and neurological diseases, among others, are developing. This review examines, for the first time, the multiple roles of GrB in disease pathogenesis.

Abnormal liver function in common variable immunodeficiency disorders due to nodular regenerative hyperplasia

Patients with common variable immunodeficiency disorders are monitored for liver function test abnormalities. A proportion of patients develop deranged liver function and some also develop hepatomegaly. We investigated the prevalence of abnormalities and types of liver disease, aiming to identify those at risk and determine outcomes. The local primary immunodeficiency database was searched for patients with a common variable immunodeficiency disorder and abnormal liver function and/or a liver biopsy. Patterns of liver dysfunction were determined and biopsies reviewed. A total of 47 of 108 patients had deranged liver function, most commonly raised alkaline phosphatase levels. Twenty-three patients had liver biopsies. Nodular regenerative hyperplasia was found in 13 of 16 with unexplained pathology. These patients were more likely to have other disease-related complications of common variable immunodeficiency disorders, in particular non-coeliac (gluten insensitive) lymphocytic enteropathy. However, five had no symptoms of liver disease and only one died of liver complications. Nodular regenerative hyperplasia is a common complication of common variable immunodeficiency disorders but was rarely complicated by portal hypertension.

Increased T-cell sinusoidal lymphocytosis in liver biopsies in patients with chronic hepatitis C and mixed cryoglobulinemia

Mixed cryoglobulinemia (MC) has a strong association with hepatitis C virus (HCV) infection and is associated with a higher degree of fibrosis and poor response to therapy. Currently, there are no known histological findings on liver biopsy that correlate with the presence of MC in HCV-infected patients, although we have occasionally noted prominent sinusoidal lymphocytosis in MC patients. The goal of this study is to determine whether sinusoidal lymphocytosis is a histological marker of MC in liver biopsies from patients with chronic hepatitis C. The liver clinic database at our institution was searched for chronic hepatitis C patients with MC who underwent liver biopsy during 1999-2005. Ten such cases were identified and were included in the study. Ten chronic hepatitis C MC-negative cases were matched for age and stage of fibrosis to serve as controls. Histological features (sinusoidal lymphocytes, inflammatory activity, acidophil bodies, and fibrosis stage) were evaluated in each biopsy. Clinical and laboratory data (serum protein electrophoresis, liver enzymes, hepatitis C viral load, treatment status, comorbidities, etc.) were also recorded. Formalin-fixed, paraffin-embedded sections were submitted for immunohistochemical analysis using antibodies against CD3, CD20, CD4, CD8, and CD68. Sinusoidal lymphocytes were counted in 5 hpf (40x) on hematoxylin and eosin (H&E) stain, and on CD3 and CD20 immunostains. The number of CD68+ Kupffer cells was also counted in a similar fashion. In the MC-positive versus MC-negative cases, mean fibrosis stage (2.4 vs. 2.4), inflammatory grade (1.7 vs. 2.1), lymphocyte count (359 vs. 128/5 hpf), and Kupffer cell count (239 vs. 220/5 HPF) were assessed. There was a significant increase in sinusoidal T-cell lymphocytes (P < 0.05) in MC-positive cases as compared to MC-negative cases. Nearly all sinusoidal lymphocytes were CD8-positive cells in both groups. Other histological parameters did not differ in the two groups. MC-positive cases tended to have a lower viral load as compared to controls (P= 0.059). The role of sinusoidal T cells in the pathogenesis of MC is currently unknown. It is unclear if the presence of these cells implies ongoing antigenic stimulation that may lead to increased risk of lymphoma. This feature may be an important clue to predict the presence of MC, an HCV-associated phenomenon that has important implications for response to treatment and disease progression.

Nodular regenerative hyperplasia: the main liver disease in patients with primary hypogammaglobulinemia and hepatic abnormalities

BACKGROUND/AIMS

Liver lesions associated with primary hypogammaglobulinemia have been poorly described. We aimed to assess the clinical, histological and immune features and outcome of hepatic injury in patients with primary hypogammaglobulinemia.

METHODS

The medical records of 51 patients (23 patients with liver biopsy) with primary hypogammaglobulinemia and liver abnormalities were retrospectively reviewed. Forty-three controls with primary hypogammaglobulinemia but with no hepatic manifestations were analyzed in parallel.

RESULTS

Cholestasis (65%), mainly anicteric, and portal hypertension (50%) were the main hepatic manifestations. Histological analysis revealed non-fibrosing architectural abnormalities consistent with nodular regenerative hyperplasia (NRH) in 84% of CVID patients and in all HIGM and XLA patients. Intrasinusoidal lymphocytic infiltration, abnormalities of portal vessels and epithelioid granulomas were observed in 90%, 43% and 44% of patients, respectively. NRH was associated with portal hypertension in 75% of the cases. These patients more often presented with autoimmune diseases and peripheral lymphocytic abnormalities than control patients (p < 0.05).

CONCLUSIONS

Liver involvement in primary hypogammaglobulinemia mainly consists of NRH leading to chronic cholestasis and portal hypertension. Association with intrasinusoidal T cell infiltration, portal vein endotheliitis, autoimmune diseases and peripheral lymphocytic abnormalities suggests an autoimmune mechanism.