Reduced serum levels of immunoreactive erythropoietin in patients with cirrhosis and chronic anemia

Hepatic erythropoietin response in cirrhosis

BACKGROUND

Erythropoietin (EPO) is produced in the liver during fetal life, but after birth the production shifts to the kidneys. The liver maintains a production capacity of 10% of the total EPO-production, but can be up-regulated to 100%. Previous studies have demonstrated both elevated and reduced concentrations of EPO in cirrhosis. Increased EPO concentrations could be expected due to anemia, hypoxia, renal hypoperfusion, or EPO-mediated hepatoprotective mechanisms. In contrast, poor hepatic production capacity may cause reduced EPO concentrations in cirrhosis. In the present paper we aimed to study hepatic and renal venous concentrations of EPO in relation to the severity of the disease.

MATERIALS AND METHODS

We included 24 patients with alcoholic cirrhosis and eight age-matched healthy controls. All had a full catheterization performed with the determination of EPO concentrations in the hepatic, renal and femoral veins and artery. All patients were clinically, biochemically, and hemodynamically characterized.

RESULTS

The median arterial EPO concentrations in the cirrhotic patients and controls were 7.1 mIU/mL (range 3.5-179) and 7.2 mIU/mL (range 3.8-15.3), respectively. In the patient group we found no significant correlations to stage of disease of hemodynamic derangement.

CONCLUSION

We found no significant differences in EPO concentrations across the liver, kidney, or peripheral circulation in the patient or control groups; and no significant correlations to clinical, biochemical, or hemodynamic characteristics. This suggests that hepatic EPO synthesis is not enhanced in cirrhosis, but larger scale studies are needed to clarify this question.

Decreased serum hepcidin concentration correlates with brain iron deposition in patients with HBV-related cirrhosis

Purpose

Excessive brain iron accumulation contributes to cognitive impairments in hepatitis B virus (HBV)-related cirrhotic patients. The underlying mechanism remains unclear. Hepcidin, a liver-produced, 25-aminoacid peptide, is the major regulator of systemic iron metabolism. Abnormal hepcidin level is a key factor in some body iron accumulation or deficiency disorders, especially in those associated with liver diseases. Our study was aimed to explore the relationship between brain iron content in patients with HBV-related cirrhosis and serum hepcidin level.

Methods

Seventy HBV-related cirrhotic patients and forty age- sex-matched healthy controls were enrolled. Brain iron content was quantified by susceptibility weighted phase imaging technique. Serum hepcidin as well as serum iron, serum transferrin, ferritin, soluble transferrin receptor, total iron binding capacity, and transferrin saturation were tested in thirty cirrhotic patients and nineteen healthy controls. Pearson correlation analysis was performed to investigate correlation between brain iron concentrations and serum hepcidin, or other iron parameters.

Results

Cirrhotic patients had increased brain iron accumulation compared to controls in the left red nuclear, the bilateral substantia nigra, the bilateral thalamus, the right caudate, and the right putamen. Cirrhotic patients had significantly decreased serum hepcidin concentration, as well as lower serum transferring level, lower total iron binding capacity and higher transferrin saturation, compared to controls. Serum hepcidin level negatively correlated with the iron content in the right caudate, while serum ferritin level positively correlated with the iron content in the bilateral putamen in cirrhotic patients.

Conclusions

Decreased serum hepcidin level correlated with excessive iron accumulation in the basal ganglia in HBV-related cirrhotic patients. Our results indicated that systemic iron overload underlined regional brain iron repletion. Serum hepcidin may be a clinical biomarker for brain iron deposition in cirrhotic patients, which may have therapeutic potential.

Darbepoetin-α inhibits the perpetuation of necro-inflammation and delays the progression of cholestatic fibrosis in mice

Biliary obstruction and cholestasis result in hepatocellular necro-inflammation and lead to the development of liver fibrosis. The objective of this study was to analyze whether the multiple tissue-protective properties of erythropoietin are salutary in an experimental model of liver fibrosis. For this purpose, C57BL/6J mice underwent common bile duct ligation (BDL) and were treated with either darbepoetin-α (10 μg/kg i.p.) or physiological saline every third day, beginning 24 h after BDL. Mice were killed at 2, 5, 14, and 28 days after BDL. Beside hematological parameters, markers of inflammation and fibrosis were assessed histomorphometrically and immunohistochemically as well as by quantitative real-time PCR. In addition, a 7-week survival study was performed. BDL provoked cholestatic hepatitis characterized by biliary infarcts with accumulation of macrophages followed by marked collagen deposition and increased expression of profibrotic gene transcripts. Darbepoetin-α treatment significantly diminished the area of focal necrosis, reduced the infiltration of macrophages, decreased levels of profibrotic genes, and lowered collagen deposition. Moreover, darbepoetin-α significantly reduced systemic anemia caused by BDL. Finally, darbepoetin-α treatment significantly prolonged the survival time after BDL. This study suggests that darbepoetin-α, which is a clinically well-established substance, might be used as an efficient therapeutic option for patients with chronic cholestatic liver disease.

Endotoxaemia in the pathogenesis of cytopenias in liver cirrhosis. Could oral antibiotics raise blood counts?

Cytopenias are frequently observed in patients with cirrhosis and are associated with increased morbidity. In particular, thrombocytopenia can impact routine care of patients with cirrhosis by potentially postponing or interfering with diagnostic and therapeutic procedures including liver biopsy and medically indicated or elective surgery. The pathogenesis of cytopenias in cirrhosis remains largely unknown. Historically, the concept of hypersplenism has long been associated with the cirrhosis-related hematological disorders but was never proven. On the other hand, intestinal bacterial overgrowth and altered gut permeability in cirrhotic patients lead to increased translocation of bacteria and endotoxin into the portal circulation. The impaired phagocytic function of the reticuloendothelial system together with the portosystemic shunting allow endotoxin to reach the systemic circulation and high concentrations of circulating endotoxin are found in cirrhotic patients even with no clinical evidence of infection and correlate with the severity of liver disease. Endotoxin activates monocytes and promotes the release of proinflammatory cytokines. Indeed, serum levels of interleukin-1, interleukin-6, tumor necrosis factor-α, and interferon-γ are elevated in patients with cirrhosis in proportion to the severity of liver disease. Endotoxaemia stimulates the vascular production of nitric oxide (NO) directly or indirectly via the cytokine cascade, and correlates with serum NO metabolite levels in cirrhosis. Several lines of evidence strongly suggest that endotoxaemia may reduce peripheral blood counts either directly or through the release of cytokines and NO. Previous studies in experimental models of cirrhosis and cirrhotic patients have demonstrated that long-term administration of oral antibiotics such as trimethoprim-sulfamethoxazole, norfloxacin, and rifaximin can reduce bacterial translocation and circulating levels of endotoxin, TNF-α, IL-6, and NO. We hypothesize that endotoxaemia plays a pivotal role in the pathogenesis of cytopenias in cirrhosis and that intestinal decontamination could raise peripheral blood counts by the suppression of endotoxaemia and the inhibition of cytokine and NO production.

Spur cells and spur cell anemia in hospitalized patients with advanced liver disease: Incidence and correlation with disease severity and survival

AIM

Spur cell anemia (SCA) is a form of acquired hemolytic anemia seen in patients with advanced cirrhosis and particularly in patients with alcoholic cirrhosis. The aim of the present study was to evaluate the incidence of spur cells and spur cell anemia in patients with advanced liver disease and to correlate the presence of spur cell anemia with survival.

METHODS

During a 33-month period, all patients with advanced cirrhosis (Child-Pugh-Turcott score [CPT]>/=7] who were hospitalized in our department for various reasons were included in this study.

RESULTS

A total of 54 patients were included in the study; 26 patients had spur cells on peripheral blood smear (median 4, range 1-14). Patients with spur cells had more advanced liver disease compared with those without spur cells (CPT score, P < 0.0001 and MELD score, P < 0.0001), lower hemoglobin levels (P < 0.0001), higher bilirubin levels (total/unconjugated, P < 0.0001), higher reticulocyte count (P < 0.0001) and more prolonged international normalized ratio (INR; P < 0.0001). Patients with 5% spur cells or more had more advanced disease compared with patients with 1-4% spur cells (CPT score, P = 0.004 and MELD score, P = 0.003), lower hemoglobin levels (P = 0.033), more elevated bilirubin levels (total/unconjugated, P = 0.006) and more prolonged INR (P = 0.04). Three-month survival was lower in patients with spur cells compared with patients without spur cells (P = 0.017 and P = 0.104, respectively). Patients with 5% spur cells or more had lower 3-month survival compared with those with 1-4% spur cells (P = 0.014).

CONCLUSION

Presence of spur cells in patients with advanced cirrhosis is not always accompanied by spur cell anemia. The presence of 5% spur cells or more and/or hemolytic anemia is associated with poor prognosis and these patients might have to be given priority for liver transplantation.

Medical and economic impact of anemia in hospitalized patients

PURPOSE

Studies indicate that the prevalence of anemia in a number of patient populations is more common than originally thought, and that more patients go untreated. Current trends in the prevalence of anemia and the consequences of untreated anemia are described.

SUMMARY

Untreated anemia is linked as an independent risk factor to increased mortality, morbidity, decreased efficacy of chemotherapy and radiotherapy in cancer treatment, and lengthened hospital or intensive care unit length of stay. Anemia is also associated with increased mortality in patients with congestive heart failure or left ventricular dysfunction.

CONCLUSION

Anemia is prevalent in the oncology and critical care populations, yet is a neglected diagnosis. It is well established that anemia has been associated with increased morbidity and mortality, and can adversely impact therapy effectiveness. Effective treatment of anemia should be based on an understanding of the patient's physiological response to anemia and achieving optimal oxygenation levels while minimizing risks and complications common to the critical care patient.

Analysis of factors contributing to higher erythropoietin levels in patients with chronic liver disease

BACKGROUND

Dysregulated erythropoietin (EPO) plasma levels may play a role in the pathophysiology of chronic liver disease (CLD) because chronic anaemia is frequently observed in patients with liver cirrhosis. We aimed to identify the factors contributing to EPO regulation in patients with CLD.

METHODS

Plasma EPO concentrations were correlated with clinical and laboratory parameters in 111 CLD patients and 220 healthy controls.

RESULTS

Anaemia, though generally mild, was common in CLD patients, and thrombocytopenia and previous bleeding episodes were observed in two-thirds of the patients. Plasma EPO levels were significantly elevated in CLD patients (P < 0.001). EPO increased according to Child's stages of cirrhosis, independently of the aetiology of CLD. EPO correlated with haemoglobin (r= -0.498, P < 0.001). Additionally, EPO independently correlated with markers of liver dysfunction, e.g. prothrombin time, albumin concentration or cholinesterase activity, and platelet count. EPO was also significantly elevated in patients with a current bleeding tendency and with prior gastrointestinal haemorrhages. EPO levels were increased in patients with impaired pulmonary function, e.g. decreased diffusion capacity, vital capacity or hyperventilation. Interestingly, plasma interleukin-6 (IL-6) concentrations positively correlated with EPO (r=0.277, P = 0.003), suggesting a possible mechanism of EPO upregulation in patients with CLD through IL-6 dependent pathways, e.g. binding of STAT transcription factors in the putative EPO promoter region.

CONCLUSIONS

EPO is upregulated in patients with chronic liver diseases in response to anaemia, bleeding complications, impaired pulmonary function, thrombocytopenia and liver dysfunction. IL-6 dependent pathways could be involved in mediating elevated EPO levels in CLD patients.

Plasma erythropoietin level in patients with cirrhosis and its relationship to the severity of cirrhosis and renal function

BACKGROUND AND AIM

The level of plasma erythropoietin (EPO) in patients with cirrhosis is controversial. It is known that overproduction of nitric oxide (NO) plays, in part, a role for the development of peripheral arterial vasodilatation in cirrhosis with portal hypertension. It has also been hypothesized that a possible interaction is noted between endogenous EPO and NO production. The current study was undertaken to evaluate the relationship between plasma EPO levels and the severity of liver disease, hemodynamic values, renal functions, and plasma nitrate/nitrite levels in patients with cirrhosis.

METHODS

The authors measured the biochemistry, plasma EPO and nitrate/nitrite levels in 67 patients with cirrhosis (Child-Pugh class A in 23 and Child-Pugh class B and C in 44) and compared their values with those in 34 healthy subjects. Systemic and splanchnic hemodynamic measurements and effective renal plasma flow were obtained from cirrhotic patients.

RESULTS

Plasma EPO and nitrate/nitrite levels were significantly increased in patients with cirrhosis compared with healthy subjects. Additionally, plasma EPO values were higher in cirrhotic patients with ascites or with anemia than in those without ascites or without anemia, respectively. Plasma EPO levels were positively correlated to the hepatic venous pressure gradient (HVPG) and Child-Pugh score, negatively correlated to the renal and hepatic blood flows, but were not correlated to nitrate/nitrite level and systemic vascular resistance in cirrhotic patients. Multiple regression analysis showed that HVPG and renal plasma flow were independent predictors for the elevated EPO level in cirrhotic patients.

CONCLUSIONS

Plasma EPO levels were increased in patients with cirrhosis compared with those in healthy subjects. The increase in plasma EPO levels is related to the degree of portal hypertension, the severity of cirrhosis and the renal plasma flow. In contrast, the EPO levels had no correlation to the nitrate/nitrite levels and systemic vascular resistance in patients with cirrhosis.

Hypersplenism

Cytopenias in liver disease are a common finding. In the past they have mostly been attributed to pooling and/or destruction of blood cells in the enlarged spleen, leading to the term 'hypersplenism'. With recent advances in the understanding of the physiology of blood formation, in particular with the discovery of several haematopoietic growth factors, new insight into the pathophysiology of blood cell derangements in liver disease has been obtained. Recombinant haematopoietic growth factors present new opportunities for support of the haematopoietic system, which is required because of toxic antiviral therapies or surgical interventions in these patients.

Increased erythropoietin synthesis in patients with COLD or left heart failure is related to alterations in renal haemodynamics

The mechanisms controlling erythropoietin (EPO) synthesis by the kidney in patients with chronic obstructive lung disease (COLD) or congestive left heart failure (CLHF) remain incompletely understood. Renal dysfunction occurs as a consequence of decreased renal blood flow (RBF) in these diseases. Because alterations in renal haemodynamics may affect EPO synthesis and red blood cell production, we investigated the potential relationships between renal function and plasma EPO synthesis in patients with COLD or CLHF. Thirty-two patients with COLD and 13 with CLHF underwent determination of renal physiology parameters, plasma EPO levels and haemoglobin levels. Plasma EPO concentrations were increased in patients with COLD or CLHF as compared to normal subjects, and were inversely correlated to haemoglobin concentrations. In patients with COLD or CLHF, plasma EPO was negatively correlated with both RBF and renal oxygen delivery (ROD) and positively correlated with filtration fraction. Plasma EPO was not correlated with glomerular filtration rate, fractional excretion of sodium, PO2 or PCO2. Among the patients with COLD, those with polycythemia (haemoglobin > 150 g L-1) had lower plasma EPO and higher RBF and ROD values than those with normocythemia (haemoglobin < or = 150 g L-1). Taken together, our data suggest that in patients with COLD or CLHF the critical determinant for EPO production is impairment of renal haemodynamics.

Splenomegaly, hypersplenism and coagulation abnormalities in liver disease

Splenomegaly is a frequent finding in patients with liver disease. It is usually asymptomatic but may cause hypersplenism. Thrombocytopenia is the most frequent manifestation of hypersplenism and may contribute to portal hypertension related bleeding. A number of therapies are available for treating thrombocytopenia due to hypersplenism including splenectomy, partial splenectomy, partial splenic embolization, TIPS etc. None is entirely satisfactory. Hypersplenism usually improves following liver transplantation. Therapy with cytokines such as thrombopoietin may offer hope for the future. Patients with liver disease also have abnormalities in coagulation. This is not surprising as all coagulation proteins (except for von willebrand factor vWF) and most inhibitors of coagulation are synthesized in the liver. Genetic or acquired abnormalities of coagulation may predispose to thrombosis of the hepatic or portal veins with significant clinical sequelae. An understanding of the mechanisms involved in coagulation and thrombosis is valuable in choosing from the increasing treatment options available. These include clotting factors, haemeostatic drugs and newer therapies such as recombinant factor VIIa. Splenic artery aneurysms are the most common visceral artery aneurysms in man. Rupture is frequently catastrophic. These aneurysms are being increasingly recognized in liver transplant patients and require treatment before or during transplant surgery.

The blood in systemic disorders

* The high rate of proliferation required of the bone marrow renders it highly susceptible to the influence of external factors. * Anaemia is the most common haematological abnormality seen in systemic disorders. * In the anaemia of chronic disease, erythropoietin production is reduced and proliferation of erythroid progenitor cells is also impaired; this anaemia can generally be alleviated by correction of the underlying disease process. * The status of the endocrine system must always be considered in evaluation of a normocytic, normochromic anaemia. * Anaemia in infection can be due to host or parasite factors or to the treatment administered. * Anaemia due to malignant disease responds to erythropoietin therapy in many cases; failure to respond is a poor prognostic sign.

Effect of anaemia on haemodynamics in patients with cirrhosis

BACKGROUND

It has been suggested that increased blood haemoglobin attenuates splanchnic vasodilatation in portal-hypertensive rats by nitric oxide inactivation. However, the haemodynamic effect of anaemia in cirrhotic patients of varying severity has been rarely discussed. The aim of this study was to evaluate the influence of anaemia on systemic and splanchnic haemodynamics in cirrhotic patients of differing severity.

METHODS

Two hundred and twenty-five cirrhotic patients were included in this study. All biochemical and haemodynamic results were utilized for analysis. Anaemia was defined as a haemoglobin level below the cut-off value of 12 g/dL, which might best predict low systemic vascular resistance.

RESULTS

Compared with non-anaemic patients, anaemic patients had decreased mean arterial pressure (90 +/- 1 vs 95 +/- 1 mmHg, P = 0.002), and decreased systemic vascular resistance (1022 +/- 25 vs 1227 +/- 30, P < 0.0001), and increased cardiac index (4.3 +/- 0.1 vs 3.8 +/- 0.1 L/min per m2, P < 0.0001) and increased hepatic venous pressure gradient (16.7 +/- 0.5 vs 14.4 +/- 0.6 mmHg, P = 0.006). Haemoglobin concentration exerted an influence on the degree of vasodilatation in cirrhotic patients, with Child-Pugh's A class (but not in Child-Pugh's B and C classes), and in patients without ascites (but not in patients with ascites).

CONCLUSIONS

It was concluded that anaemia has a negative effect on hyperdynamic circulation in patients with early cirrhosis which is not observed in patients with advanced cirrhosis.

Blunted serum erythropoietin response to anemia in patients polytransfused for beta-thalassemia major

PURPOSE

To investigate the response of erythropoietin (EPO) to anemia in patients polytransfused for beta-thalassemia major.

PATIENTS AND METHODS

We measured the serum EPO levels and the concurrent hemoglobin (Hb) concentrations in 40 patients polytransfused for beta-thalassemia major, in 18 patients with iron deficiency anemia (IDA), and 32 healthy subjects. Serum EPO levels were assayed by an enzyme immunoassay.

RESULTS

In both groups with beta-thalassemia major and IDA, serum EPO levels were significantly elevated (114 +/- 71 and 239 +/- 217 mU/mL, respectively). There was a significant inverse correlation between log EPO values and Hb concentrations in patients with beta-thalassemia major (r = 0.61; p < 0.01) and IDA (r = 0.81; p < 0.01). In a semilogarithmic plot, the slope of the regression line obtained in patients with beta-thalassemia major was significantly lower than that of IDA (p < 0.01), suggesting a blunted EPO response to anemia in patients polytransfused for beta-thalassemia major. The elevation of serum EPO in patients with beta-thalassemia major was poorly related to clinical variables except serum ferritin.

CONCLUSIONS

We conclude that a significant inverse relationship between serum EPO levels and Hb concentration exists in patients with beta-thalassemia major. However, this EPO response in patients with anemia caused by beta-thalassemia major may be blunted when compared to patients with IDA.