Nature and Incidence of Liver Involvement in Agnogenic Myeloid Metaplasia

Abstract

Clinical, biochemical and histopathological data of 33 patients with agnogenic myeloid metaplasia (AMM) were examined with reference to liver disease and dysfunction. Clinical manifestations of hepatic or portal system involvement included hepatomegaly, jaundice, hepatitis, gall stones, ascites and bleeding esophageal varices. The liver was smooth and firm; it became larger with progression of the disease, but to a lesser degree than the spleen. Mild indirect bilirubinaemia occurred in the course of the disease in about half of the patients. Hepatitis was diagnosed in 5 (15 %) patients and in 3 (10 %) cases it was the cause of death. Cholelithiasis was found in 4 (12 %) patients. Biochemical liver dysfunction occurred in 22 (66 %) patients. A progressive increase in serum alkaline phosphatase and a gradual decrease in serum albumin were observed in 4 patients, who were followed for 5 to 15 years. Hepatic myeloid metaplasia was found in all 20 patients examined histologically. The liver architecture was grossly distorted in 4 cases: in 2 this was due to impaction of the sinusoid with haemopoietic cells, and in the remaining 2 to necrosis and haemorrhage following viral hepatitis. Periportal fibrosis was observed in 6 (30 %) of the liver specimens. Ascites, portal hypertension, or both, were found in 7 (64 %) of the 11 autopsies and in 5 (22 %) of the remaining patients. Liver histology, examined in 11 patients, revealed periportal fibrosis in 5 cases and myeloid metaplasia only, in the remaining 5. Patients with ascites or portal hypertension exhibited more frequently increased levels of serum alkaline phosphatase and vitamin B12, and lower levels of plasma prothrombin and serum albumin. The pathogenesis of the hepatic and portal system involvement in agnogenic myeloid metaplasia (AMM) remains uncertain. Mechanical pressure by foci of myeloid metaplasia, chronic passive congestion, hepatitis or combinations of the above may lead to atrophy or necrosis of the parenchyma, followed by reparative fibrosis. Portal hypertension and ascites, a common complication of advanced AMM, could be due to the combined effect of an increased blood flow in the portal system, hypoalbuminaemia and sinusoidal obstruction.

Liver involvement at diagnosis of primary myelofibrosis: A clinicopathological study of twenty‐two cases

“…The absence of myeloid metaplasia within the portal areas is in contrast with the findings in other series includingnecroptic or notinitial biopsy specimens (4, 6), and suggests that portal involvement would be a feature of advanced disease. The frequency of hepatic fibrosis in PMF varies from study to study (3,6). We found a reticulin network increase in 40% of samples, although collagen deposition was only observed in a case in which it could be ascribed to concurrent chronic active hepatitis.…”

“…P M F is a haematological disorder characterized by increased bone marrow fibrosis and myeloid metaplasia in the absence of other potentially causative conditions (1). The spleen and the liver are the organs most frequently involved by myeloid metaplasia, the frequency of HMM demonstrated by biopsy or at necropsy ranging from 90% to 100% (2)(3)(4)(5)(6).…”

Clinical Features of Patients With Philadelphia-Negative Myeloproliferative Neoplasms Complicated by Portal Hypertension

“…Most of the current literature is in the form of anecdotal case reports or small retrospective series. PHTN has been reported in approximately 7%-18% of patients with MPN, many of whom present with variceal bleeding or ascites 1-2 . Several case reports have demonstrated the use of endoscopic variceal ligation or sclerotherapy to control esophageal varices, as well as the use of transjuglar intrahepatic portosystemic shunts for refractory ascites 3-4 .…”

Portal hypertension secondary to myelofibrosis with myeloid metaplasia: A study of 13 cases

“…PH has been reported in 7%-18% of AMM, which represents a subgroup of MMM [8,9] . In this study, simple mathematical calculation revealed an 11% prevalence of symptomatic PH in MMM.…”