Myeloid metaplasia, perisinusoidal fibrosis, and nodular regenerative hyperplasia of the liver

Obliteration of liver sinusoids through platelet aggregates associated to extramedullary haematopoiesis in myeloid neoplasms

Herein is reported a series of five patients with myeloid neoplasms presenting hepatic complications in whose liver biopsy revealed obstruction of sinusoids by platelet aggregates associated to liver extramedullary haematopoiesis. Indication of liver biopsies was jaundice, unexplained hepatomegaly or portal hypertension. Haematological disorders were classified according to the World Health Organisation. Molecular profile was established in all cases as well as grade of liver extramedullary haematopoiesis and myelofibrosis. The patients were four men and one woman aged from 50 to 82 years. Two patients had myeloproliferative neoplasm (triple negative primary myelofibrosis and JAK2-mutated essential thrombocytopenia), two patients had unclassifiable myelodysplastic/myeloproliferative neoplasm and one patient had chronic myelomonocytic leukaemia type 1. Liver biopsies revealed platelet aggregates occluding sinusoids in association with extramedullary haematopoiesis grade 1 in one patient, grade 2 in two patients and grade 3 in two patients. Two of these patients presented co-existing liver fibrosis due to chronic alcoholic consumption and ischemic heart failure. These five patients died from 2 to 23 months after liver biopsy due to acute myeloblastic leukaemia (three patients), portal hypertension (one patient) or other causes (acute heart failure). Intrahepatic sinusoidal microthromboses through platelet aggregates might cause portal hypertension or liver deficiency in patients with myeloid neoplasms, independently of JAK2 mutational status and grade of extramedullary haematopoiesis.

Hepatoportal sclerosis in childhood: some presenting with cholestatic features (a re-evaluation of 12 children)

Hepatoportal sclerosis (HPS) is a syndrome of obscure etiology, and is one of the causes of noncirrhotic portal hypertension (PH). We aimed to investigate this heterogeneous group of patients whose presentation showed cholestatic features, histopathologically. Between 1999 and 2009, 12 children diagnosed with HPS were retrospectively evaluated. HPS was diagnosed with evidence of PH, noncirrhotic liver biopsy with typical histopathologic findings, and exclusion of other possible causes of PH. The data was obtained from pathology reports and microscopic slides. In histopathological re-evaluation fibrosis state, aberrant portal vessels, portal tract dilation and inflammation, ductular reaction, regenerative nodular hyperplasia, acinar transformation, presence of bile pigment, and cholangitis were noted. Serum alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl, alkaline phosphatase, bilirubin, and albumin levels, presentation patterns, and radiologic findings were assessed. Familial relationship degrees were also investigated. Twelve patients (9 boys, 3 girls; 3-180 months) were re-evaluated. Two pairs of the patients were siblings. Parents of 7 patients were consanguine. The most common presenting symptom was abdominal distension. Histopathologically, all patients had hepatoportal sclerosis/intimal fibrous thickening of portal vein and periportal fibrosis, acinar transformation, and regenerative nodules not surrounded by fibrous septae. Eight patients had vascular aberrations, 7 had ductular reaction, 1 showed mild cholangitis, and 1 had canalicular bile pigment. We conclude that genetic predisposition might be a possible factor for HPS development in Turkish patients and it should be kept in mind that cholestatic features noticed in histopathological evaluation may represent a variant group in the spectrum of HPS.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Massive ascites caused by peritoneal extramedullary hematopoiesis as the initial manifestation of myelofibrosis

An 83-year-old man presented with massive ascites. Cytological examination of the ascites revealed primitive hematopoietic cells. The specimen of bone marrow biopsy disclosed diffuse fibrosis, which suggested myelofibrosis with extramedullary hematopoiesis as the cause of ascites. His symptoms resolved dramatically after administration of hydroxyurea. Ascites formation in myelofibrosis is often attributed to presinusoidal portal hypertension and occurs in the context of well-established disease. This case demonstrates that myelofibrosis may manifest as massive ascites caused by peritoneal implants of myeloid tissues. Extramedullary hematopoiesis should be included in the differential diagnosis of ascites.

Noncirrhotic portal hypertension

This article reviews the different conditions leading to noncirrhotic intrahepatic portal hypertension, describes the related vascular lesions, and provides a review of the clinical characteristics, diagnosis, and treatment options available. Diseases associated with noncirrhotic portal hypertension are also specifically discussed.

Nodular regenerative hyperplasia of the liver in rheumatic diseases: report of seven cases and review of the literature

Nodular regenerative hyperplasia (NRH) of the liver is an uncommon pathologic finding associated, in most cases, with rheumatic and hematologic diseases. Although its pathogenesis remains unclear, NRH probably results from liver regeneration to maintain its functional capacity after ischemia-induced injury. An intrahepatic microvascular occlusive mechanism has been considered most likely pathogenetically. NRH may lead to portal hypertension. Thus, the diagnosis of Felty's syndrome must be considered with caution in patients with rheumatoid arthritis (RA) and NRH of the liver. We report seven additional cases of NRH in patients with rheumatic disorders and review the literature to determine the patterns of clinical presentation and natural history of this condition. We also report four patients (three systemic lupus erythematosus [SLE] and one primary antiphospholipid syndrome [PAPS]) in whom antiphospholipid antibodies may have played a role in the genesis of NRH.

Ascites revealing peritoneal and hepatic extramedullary hematopoiesis with peliosis in agnogenic myeloid metaplasia: case report and review of the literature

A 61-year-old man presented with ascites in the course of agnogenic myeloid metaplasia (AMM). Ascitic fluid was exudative and contained mature and immature leukocytes, erythroid cells, and megakaryocytes as observed on a bone marrow smear. Peritoneal biopsy showed myeloid metaplasia, and liver biopsy revealed intrasinusoidal myeloid metaplasia and peliosis. Ascites cleared after abdominal radiotherapy but treatment resulted in transient aplasia. Subsequently, portal hypertension was demonstrated by hepatic transjugular catheterization. Complications of splenomegaly led to splenectomy and splenorenal shunt followed by fatal acute hepatitis and septic shock. A review of the literature and an analysis of mechanisms of ascites occurring in AMM, especially peritoneal implants of myeloid tissue and occurrence of peliosis in myeloproliferative disorders, are presented.

Nodular regenerative hyperplasia of the liver and the Budd-Chiari syndrome. Case report, review of the literature and reappraisal of pathogenesis

We report a case of nodular regenerative hyperplasia (NRH) of the liver associated with the Budd-Chiari syndrome in a patient whose clinical and radiological presentation suggested a diagnosis of multiple liver tumours. Based on both our study and a review of the literature, it appears that, in a number of cases of NRH associated with various clinical conditions, blood stasis at the sinusoidal level is the common denominator. We postulate that, in this situation, the prolonged exposure of hepatocytes to blood-borne hepatotrophic substances, such as hepatopoietins, glucagon and insulin, in combination with functional loss due to pressure injury within the congested areas, may be one of the mechanisms leading to the development of NRH.

Hepatic vascular disease and portal hypertension in polycythemia vera and agnogenic myeloid metaplasia: a clinicopathological study of 145 patients examined at autopsy

The pathogenesis of portal hypertension arising in patients with myeloproliferative disorders has been difficult to understand because liver biopsy findings often show minimal changes. It has been suggested that increased splenic blood flow, hepatic infiltration with hematopoietic cells or sinusoidal fibrosis may be important. We have reviewed the autopsy findings and clinical histories of 97 patients with polycythemia vera and 48 patients with agnogenic myeloid metaplasia collected from three institutions and from the Polycythemia Vera Study Group. Cirrhosis was present in seven patients, one of whom had bleeding varices. Esophageal varices were present clinically in 10 patients without cirrhosis (seven polycythemia and three agnogenic myeloid metaplasia). All of these patients had lesions in small or medium-sized portal veins and four had stenosis of the extrahepatic portal vein with histology compatible with organized thrombi. Nodular regenerative hyperplasia occurred in 14.6% and correlated closely with the presence of portal vein lesions. Thirty patients had greater than 500 ml of ascites, seven of these patients also had varices and six of them had hepatic vein thrombosis. Ascites also correlated with hepatic vein disease confined to small intrahepatic branches. No correlation was seen between hepatic hematopoietic infiltration and signs of portal hypertension. We conclude that esophageal varices are common and are almost always associated with portal vein lesions visible by light microscopy. These portal vein lesions, and the secondary effects of nodular regenerative hyperplasia and portal hypertension, are most likely a result of portal vein thrombosis in patients with myeloproliferative disorders.

Nodular regenerative hyperplasia of the liver, peliosis hepatis, and perisinusoidal fibrosis. Association with angioimmunoblastic lymphadenopathy and severe hypoxemia

Three different liver lesions were found in a 20-year-old woman with angioimmunoblastic lymphadenopathy. The lesions included nodular regenerative hyperplasia of the liver, perisinusoidal fibrosis, and peliosis hepatis. It is suggested that the association of angioimmunoblastic lymphadenopathy with this broad spectrum of liver lesions was not fortuitous.

Fine structure of hepatic sinusoids and sinusoidal cells in disease

Liver sinusoids are special capillaries that are limited by fenestrated endothelial cells, without a genuine basement membrane, surrounded by perisinusoidal cells storing vitamin A, and harbouring Kupffer cells and pit cells, resident macrophages, and large granular lymphocytes, respectively. Each nonparenchymal cell and parenchymal cell of the liver interacts with all others and with the extracellular matrix. Therefore, the functional ability of each cell is constantly being modified by the metabolic activity of the others. Human liver biopsies (132), needle or surgical, perfusion-fixed with glutaraldehyde and processed for transmission electron microscopy (TEM), and occasionally for scanning electron microscopy (SEM), were examined. The study included liver diseases (such as alcoholic liver diseases, benign and malignant liver tumors, cholestasis of various origins, fulminant hepatitis, acute rejection after orthotopic liver transplantation, Budd-Chiari syndrome), as well as general or extrahepatic diseases (such as diabetes, hemochromatosis, hypervitaminosis A, various hematological disorders), and normal controls. Ultrastructural abnormalities are described and illustrated under two different headings: 1) elementary lesions of sinusoidal cells (endothelial, Kupffer, perisinusoidal and pit cells), nonsinusoidal cells (in the space of Disse and/or in the lumen), the extracellular matrix; and 2) the major pathological entities including perisinusoidal fibrosis, capillarization of sinusoids, sinusoidal dilatation, and peliosis. In the discussion, an overview of the major abnormalities reported in the literature is presented, and some specific questions regarding 1) perisinusoidal fibrosis in liver with normal histology, 2) the overload of perisinusoidal cells with lipids in non-hypervitaminosis A intoxication and 3) the etiological relationship of sinusoidal dilatation, peliosis, perisinusoidal fibrosis, or sinusoidal tumors with drugs and toxic compounds are discussed. In the event that lesions are not specific to any diagnosis, the knowledge of the ultrastructure of sinusoids is extremely useful from the perspective of the liver as an ecosystem.

Diffuse nodular regenerative hyperplasia of the liver (DNRH). A clinicopathologic study of 24 cases

The authors report 24 cases of diffuse nodular regenerative hyperplasia of the liver (DNRH) seen in a General Hospital during the last 9 years (prevalence: 3'1/100,000, incidence: 0'34/100,000). DNRH was diagnosed in 0.52% of the liver biopsies and 0.72 of the autopsies. These results suggest that DNHR is probably more frequent than suspected, and 1 DNRH was seen for each 39 biopsied cases of liver cirrhosis. Fourteen patients did not have hepatic symptoms. Portal hypertension was present in 9 cases. The biochemical disturbance most frequently found was a moderate elevation of GGT and APh, associated with slight elevation of SGOT, SGPT and bilirubin levels. Normal liver function tests could be seen (3 cases). Previous exposure to potentially hepatotoxic drugs or chemicals was discovered in 15 cases (62.5%). Diseases associated were circulatory disturbances (6 cases), autoimmune disease (5 cases), hemopathies (5 cases), and visceral carcinomas (4 cases). Two patients were recipients of renal transplant. Nodules distributed through the whole liver tissue were found in 16 cases, while 8 patients showed areas of normal parenchyma in their livers. Impairment of small hepatic vessels was detected in 16 cases. Some uneven cytologic findings were discovered: clusters of small basophilic cells (4 cases), large clear cells (8 cases), and dysplastic hepatocytes (10 cases), which suggests that DNRH could be a preneoplastic condition.

Peliosis hepatis, nodular regenerative hyperplasia of the liver, and light-chain deposition in a patient with Waldenström's macroglobulinemia

We report the case of a female patient suffering from Waldenström's macroglobulinemia with three different liver lesions: peliosis hepatis, nodular regenerative hyperplasia, and light-chain deposits within the sinusoidal walls. We hypothesize that both peliosis hepatis and nodular regenerative hyperplasia might be the consequence of a disordered intrahepatic circulation determined by light-chain deposits infiltrating the sinusoidal walls.

Agnogenic myeloid metaplasia, portal hypertension, and sinusoidal abnormalities

A patient with agnogenic myeloid metaplasia suffered from gastrointestinal bleeding due to ruptured esophageal varices. The portal vein and its intrahepatic branches were patent. Except for the presence of myeloid cells, mainly megakaryocytes, in the sinusoids, liver histology was more or less normal. However, on Sirius red staining there was marked perisinusoidal fibrosis. In addition to numerous collagen bundles in the Disse space, electron microscopy also revealed the presence of hemopoietic cells, the transformation of perisinusoidal cells into fibroblasticlike or myofibroblasticlike cells, or both, and fragmentary deposits of basement membrane-like material. In the pathogenesis of sinusoidal hypertension as it occurs in agnogenic myeloid metaplasia, all the factors mentioned above should probably be taken into consideration.

Perisinusoidal fibrosis of the liver in patients with thrombocytopenic purpura

10 patients with thrombocytopenic purpura (TP) underwent splenectomy. Eight of these patients had idiopathic TP (certain or probable). All had normal liver function tests. Liver histology of the surgical biopsy was normal with the exception of a non specific mild portal infiltration in 6 cases. On Sirius red staining the perisinusoidal network was normal in 3 cases, mildly or moderately increased in 5 cases and often associated with perivenular fibrosis. Collagen types I, III, IV, laminin and fibronectin were increased in the 8 biopsies tested. On semi-thin sections, numerous Kupffer cells were observed. Under the electron microscope, sinusoidal abnormalities were very similar in all 7 patients studied: numerous Kupffer cells containing abundant lysosomes, numerous collagen bundles in the Disse space, active endothelial cells, transformation of some perisinusoidal cells into cells with some of the characteristics of fibroblasts (increased RER) and myofibroblasts (peripheral condensations of the filamentous network), increased fragments of basement membrane-like material. In two cases there was an increase in the number of perisinusoidal cells loaded with lipids. The similarity of the lesions and the absence of other fibrogenic causes (except in 2 cases) suggest that TP may represent another group of diseases with perisinusoidal fibrosis. The aetiology of fibrosis remains unknown but platelet derived growth factor and activated macrophages may play a major role.