Anemia in cirrhosis: An underestimated entity

INTRODUCTION

Anemia is a fairly common clinical condition. Its prevalence in the general population varies from 10%-24%[1]. However, in critically ill patients, and those with underlying malignancies or autoimmune disorders, the prevalence increases to 95%[2]. Anemia may be seen in 66%-75% of patients with liver cirrhosis[1,3]. Iron deficiency, which is the commonest type of anemia, has been observed in 22% of patients with compensated cirrhosis and 78% in those with decompensated disease. Apart from anemia, thrombocytopenia and leucopenia are other abnormal hematological indices seen in patients with cirrhosis. Thrombocytopenia is by far the commonest hematological abnormality seen in patients with cirrhosis followed by leucopenia and anemia[4]. The pathophysiological sequelae of cirrhosis adversely affect the synthetic and immunological functions of the liver. This manifests as hematological dysfunctions including anemia.

SIGNIFICANCE OF ANEMIA IN CIRRHOSIS

The presence of anemia in a cirrhotic patient can be considered a ‘vicious cycle’. The following facts need consideration: The severity of iron deficiency anemia (IDA)increases with increasing Child’s Pugh Turcotte (CTP) score: CTP A (26.5%), CTP B(59.2%), and CTP C (69%). Higher the degree of portal hypertension, the higher is the risk of developing severe anemia (< 10 gm/dL)[1]. Acute gastrointestinal (GI) bleed can be potentially catastrophic sequelae of portal hypertension[5]. Anemia by itself has been found to have an increased risk of hepatic decompensation and liver-related mortality in patients with compensated cirrhosis[6]. Anemic patients with cirrhosis have been reported to have higher model for end-stage liver disease (MELD) scores and lower albumin levels. The latest research has highlighted that hemoglobin (Hb)can be considered as a marker for severe disease. Conversely, the higher the MELD score, more likely is the possibility of having hematological complications[7]. Anemia has been postulated to have a pathophysiological role in the development of hepatorenal syndrome[8]. Besides increasing the risk of mortality, anemia is associated with a higher incidence of acute on chronic liver failure (ACLF) and increased risk of hospitalization[1]. The vicious cycle of portal hypertension, worsening disease severity, and anemia in cirrhosis are depicted in Figure 1. Moreover, blood transfusion in anemia can itself precipitate secondary iron (Fe) overload thereby increasing the risk of hepatocellular carcinoma (HCC) and mortality. Thus, it may be noteworthy to understand anemia as a part of the disease process rather than just a disease complication.

ETIOPATHOGENESIS OF ANEMIA IN CIRRHOSIS

The liver, owing to its unique portal circulation, synthetic and immunological functions can give rise to multiple hematological manifestations, and anemia in cirrhosis is often multifactorial (Table 1).

Once the predominant cause has been identified, treatment should be initiated to provide symptomatic relief besides addressing the underlying disease, reduction of portal pressure, prevention of progressive fibrosis besides management of complications, and screening for HCC. The definite treatment, however, remains as LT.

To understand the development of anemia, it is imperative to understand the critical role played by this oxygen-carrying micronutrient: Iron. 80% of the body’s total iron stores (02-04 g) are stored as Hb in red blood cells (RBC). Ferric iron (Fe)following its absorption in the duodenum is converted to ferrous iron (Fe) by the action of ferric reductase duodenal cytochrome b. This iron is transported into the cytoplasm of the enterocyte and is either stored or exported by the iron exporter enzyme ferroportin. The next step involves oxidization of Feto Feform to ferroxidase hephaestin and ceruloplasmin (Cp). Fein combination with enzyme transferrin (Tf) undergoes circulation in the body. Erythrocyte precursors, known as erythroblasts, utilize a principal portion of Tf bound iron (Figure 2). A highly efficient recycling system in the spleen and hepatic macrophages ensures optimal utilization of iron stores. Thus, the human liver is an important component of this highly efficient iron homeostasis. The liver synthesizes proteins involved in iron homeostasis: Tf (80 kDa glycoprotein), Cp (copper linked serum ferroxidase), multi-subunit protein ferritin, and a 25 amino acid peptide, hepcidin.

IDA may occur secondary to acute or chronic blood loss. The various causes are variceal hemorrhage which usually presents with an overt GI bleed, and portal hypertensive gastropathy (may present with either overt or obscure GI bleed). The incidence of duodenal ulcer and ulcer-related bleed is more common in patients with cirrhosis. Besides, nutritional deficiencies including those of iron, Vitamin (Vit) B12,B6, and folate are common in patients suffering from cirrhosis. In addition, hypersplenism secondary to portal hypertension may contribute to iron deficiency. Amongst the etiological agents leading to the development of cirrhosis, a few, in particular, have been found to have a predominant role in the pathogenesis of anemia: alcohol may cause blood loss because of alcohol-induced gastritis. It also has a direct toxic effect on erythroid precursors and may cause Vit B12, folic acid deficiency. Besides, alcoholrelated malnutrition may lead to reduced iron absorption. Hepatitis B and C may cause bone marrow aplasia, Wilson’s disease may be associated with hemolytic anemia in around 1%-12% of cases as copper released following hepatocyte necrosis causes oxidative dysfunction of phospholipids lining the RBC membrane leading to hemolysis and worsening of liver dysfunction[9]. Another form of acquired hemolytic anemia: Spur cell anemia may occur in alcohol-related cirrhosis wherein abnormal lipid metabolism leads to altered RBC membrane causing reduced deformability of RBC. A triad consisting of cholestatic jaundice, transient hyperlipidemia and hemolytic anemia — Zieve’s syndrome has been rarely reported in alcohol-related cirrhosis[10].

GI bleed is the second most common cause of decompensation in a patient with cirrhosis[38]. Bleeding esophageal varices, which constitute the predominant source of the variceal bleed, is associated with 10%-20% mortality over 6 wk. Initial management focuses on maintenance of intravascular volume and ‘restrictive transfusion strategy’, initiating transfusion at Hb level < 7 g/dL to maintain Hb between 7-9 g/dL. This has been found to have a survival benefit in patients with Child’s A and B cirrhosis and it also decreases the risk of rebleeding in all patients with cirrhosis[42,43,44].Intravenous splanchnic vasoconstrictors (terlipressin, somatostatin, octreotide),antibiotic prophylaxis, and intravenous proton pump inhibitors are recommended in the initial management of all cases of acute variceal bleed[45]. Combination treatment of endoscopic variceal ligation (EVL) and intravenous vasoconstrictors is the ‘standard of care'. Early rebleeding or failure of endoscopic therapy has been reported in 10%-15% of all patients with acute variceal bleed[5]. Rescue transjugular intrahepatic portosystemic shunt (TIPS) may be considered in such patients in addition to EVL and intravenous vasoconstrictors. Those patients with increased risk of re-bleeding (Child C status, score < 14 and no contraindications for TIPS), may be considered for preemptive TIPS and as a bridge to eventual LT[45]. Nonselective beta-blockers in addition to EVL form the cornerstone of management strategy to prevent a rebleed.

Although now of historical interest, Ribavirin, a nucleoside anti-metabolite, used in the treatment of chronic hepatitis C (CHC), causes dose-related hemolytic anemia in around 10% of patients[11]. Autoimmune hemolytic anemia may also be seen in patients with autoimmune hepatitis. D-Penicillamine, a copper chelating agent, used in the treatment of Wilson’s disease, in turn, may cause iron chelation manifesting as IDA. Another drug used in Wilson’s disease, Trientine, may cause sideroblastic anemia[9]. However, the most common cause of anemia in cirrhosis is anemia of chronic disease, which develops secondary to an underlying chronic inflammatory state. Before we proceed further to understand the pathophysiology of anemia of chronic disease in cirrhosis, it is worthwhile to mention the proposed hypothesis of‘Eryptosis’: Programmed cell death of erythrocytes which may contribute to anemia.This is akin to apoptosis of nucleated cells despite the absence of organelles involved in apoptosis. In a murine model, a high bilirubin level has been shown to increases Cainflux, sphingomyelinase activation within erythrocytes, thereby triggering eryptosis[12].

Anemia of chronic disease and the critical role of hepcidin

It is worthwhile to emphasize the role of ‘Hepcidin’ (hepatic bactericidal protein), an iron regulatory hormone, produced in excess by the liver, in maintaining iron homeostasis. Increased iron levels in plasma and increased iron storage stimulates hepcidin production which further blocks dietary iron absorption and storage. In iron deficiency states hepcidin production is suppressed, which ensures increased dietary iron absorption. Erythropoietic processes cause high iron consumption to suppress hepcidin production. This ensures that stored iron is released by hepatocytes and macrophages and intestinal absorption of dietary iron increases. In chronic inflammatory states like cirrhosis hepcidin production is mediated by two distinct mechanisms: Interleukin-6 (IL-6) (a pro-inflammatory cytokine), mediated as well as IL-6 independent pathways. It is especially pertinent to understand that in inflammatory states like cirrhosis, increased body iron stores no longer suppress hepcidin production, even if plasma iron level is low, hepcidin production is increased by IL-6 mediated pathway (while under normal circumstances, hepcidin production should have been downregulated in iron deficiency).Moreover, in cirrhosis, hepcidin is produced by myeloid cells by activating toll-like receptor-4, a receptor present on surface membranes of neutrophils and macrophages. This excess of iron gets trapped within the cells causing reduced availability of iron for forming Hb and thereby manifesting as anemia of chronic disease[2,13]. Three major pathways control stimuli related and basal hepcidin expression. The best-studied is the SMAD/bone morphogenetic signaling pathway which explains the evolution of anemia in inflammatory disorders. IL-6 is an inflammatory mediator that activates the Janus kinases-Signal transducer and activator of transcription proteins (JAK-STAT-3) pathway by binding to IL-6 receptor (IL6-R). STAT-3, in turn, causes increased hepcidin expression. The other important pathway involves binding of Tf to transferrin receptor-1 (Tfr-1) which in turn causes dissociation of transferrin receptor-1-human homeostatic iron regulator(Tfr-1 HFE complex). The available HFE interacts with Tfr-2 to increase BMP6 mediated phosphorylation of SMAD1/5/8. SMAD 1/5/8 further recruits SMAD4 to increase hepcidin expression. The least understood pathway is the one wherein hypoxia and erythropoiesis inhibit hepcidin expression by direct binding of hypoxiainducible factor (HIF) to the promoter region of the hepcidin receptor. Figure 2 explains the pathophysiological role of Hepcidin in the development of anemia[13-15].

HEPCIDIN AS A BIOMARKER IN LIVER DISEASE

Hepcidin has been postulated as a potential biomarker in liver fibrosis and cirrhosis.Alcohol, a well-established cause of liver cirrhosis has been associated with low hepcidin levels. Low hepcidin levels have been documented in individuals with chronic alcohol consumption and preserved liver functions. Low hepcidin levels have been shown to worsen liver fibrosis in patients with CHC and CHB infection as well as autoimmune liver disease. Diagnostic use however is limited by lack of standardization especially in patients with liver disease[16].

While the pathophysiological mechanisms involved in iron deficiency and chronic inflammation leading to the development of anemia in cirrhosis have been described in the literature, the pathophysiological changes leading to macrocytic anemia have been poorly understood. It has been postulated that splenomegaly secondary to portal hypertension causes secondary hemolysis which in turn causes increased plasma volume and macrocytosis. Alcohol per se can cause secondary malnutrition and folic acid deficiency besides adversely affecting erythropoiesis in the bone marrow.

TYPES OF ANEMIA IN CIRRHOSIS

To co-relate with the underlying pathogenesis and to evaluate a patient with anemia with underlying cirrhosis, anemia may be classified as per the RBC indices, as follows:Normocytic: Anemia of chronic disease; Microcytic: Acute variceal hemorrhage,chronic blood loss due to portal gastropathy, alcohol-related gastritis or intestinal malabsorption, treatment-related (D-Penicillamine); Macrocytic: Vit B12, B6, Folate deficiency; Hemolytic: Wilson’s disease, Spur cell anemia, Autoimmune hemolytic anemia, treatment-related (Ribavirin); Aplastic: Hepatitis B, hepatitis C related; and Sideroblastic: Drug-induced (Trientene in Wilson’s disease).

DIAGNOSTIC EVALUATION IN A CASE OF ANEMIA IN CIRRHOSIS

Anemia in cirrhosis is independently associated with increased mortality and morbidity. Moreover, there could be an interplay involving multiple etiologies.Therefore, it becomes imperative to have a simple, easily available, yet informative diagnostic algorithm to aid in the diagnosis and thereafter management of the predominant etiology of anemia in cirrhosis.

为方便影响因子的确定，首先对每个任务所在的经纬度坐标进行位置数据网格化处理，均分为2500个网格，每个网格对应实际面积为:

Hb level

Estimation of Hb is the initial screening method for the diagnosis of anemia. World Health Organization (WHO) classifies anemia as < 13 g/dL for men, < 12 g/dL for non-pregnant females and < 11 g/dL for pregnant females[17]. Hb, being an easily reproducible test across different laboratories and with a lower coefficient of variance vs. hematocrit, is the preferred investigation. Moreover, variables like patients’ serum glucose and storage time of samples do not affect the measurement of Hb[18].Complete cell count including WBC, DLC, and platelet count, estimate the bone marrow function. Hypersplenism, Vit B12 deficiency, aplasia secondary to hepatitis B or C may cause pancytopenia in patients with cirrhosis.

Absolute reticulocyte count and reticulocyte index

The level of transferrin receptors in the serum can be used to ascertain the iron stores.It can be used to differentiate IDA (levels raised in IDA) from anemia of chronic disease[38]. In patients with cirrhosis, serum transferrin receptor is 91.6% sensitive and 84.6% specific to diagnose IDA in the absence of hemolysis and acute blood loss[39].Lack of standardized tests, availability, and cost remain the limitations to its widespread use in clinical setting[37].

RBC indices

Red cell distribution width: Red cell distribution width (RDW) has been suggested as a potential marker of inflammatory diseases. Studies on this aspect have shown conflicting results. Some researchers have postulated that RDW increases with worsening liver disease. They have shown that increased RDW is associated with increased 3-mo mortality in decompensated cirrhosis[20,21]. Other researchers,however, have provided evidence to the contrary and failed to prove any statistical significance with worsening liver disease or any significance in differentiating the type of anemia in cirrhosis[22].

MCV

The management of anemia in a patient with cirrhosis may be considered under the following subheads: Patients with ongoing/acute bleeding; Patient without active/acute bleeding.

Serum iron studies

Serum ferritin: The hepatocyte is the principal site of production of ferritin, a marker of iron homeostasis and an acute phase reactant. Serum ferritin level < 30 μg/dL has a sensitivity of 92% to diagnose IDA in the general population[28,29]. However, in patients with underlying inflammatory disorders and cirrhosis a value < 100 μg/dL has a better predictive value to diagnose IDA[30]. Systemic analysis on the utility of measuring ferritin in patients with cirrhosis revealed that values, 15 g/dL were highly specific to establish a diagnosis of IDA in cirrhosis while values > 100 g/dL virtually ruled out IDA[31].

通过静脉溶栓治疗能够有效增加患者的冠状动脉血液供应，促使心肌梗死面积缩小，避免心肌缺血进一步扩大，从而促使患者的病情在短时间内得到有效的控制。尿激酶是临床上常用的一种静脉溶栓药物，该药物无抗性，可将纤溶酶原转化为纤溶酶，促使纤维蛋白进行降解，从而达到溶栓的目的[11-12]。但在实施静脉溶栓治疗的过程中，需注意一个问题，即在静脉溶栓治疗过程中患者的纤溶系统和凝血系统会被同时激活，此时血小板的作用会非常突出，因此，对于行静脉溶栓治疗的患者来说，需在治疗前给予阿司匹林来抵抗血小板的作用[13]。

Another important fact worth considering is that 10%-30% of patients with cirrhosis have iron overload. This is particularly significant in individuals with nonalcoholic fatty liver disease, alcoholic liver diseases, CHC, and primary biliary cholangitis.Excess iron has been demonstrated in 8% of patients with an advanced liver disease akin to hemochromatosis even in the absence of specific genetic mutations. Iron excess may initiate the second process of liver injury and increases the risk of HCC[32].Besides diagnosing IDA and predicting increased risk of HCC, elevated levels of serum ferritin have also been shown to independently predict mortality similar to MELD score in patients of end-stage liver disease[33].

TSAT

High serum ferritin and low transferrin are oft-reported findings in cirrhosis.Available literature suggests that transferrin and TSAT are independent predictors of mortality in ACLF and decompensated Cirrhosis[34]. TSAT value < 20% may be considered the level to initiate treatment for IDA[35]. EASL recommends TSAT > 45%in females and > 50% in males as a screening biochemical test for hereditary hemochromatosis[36]. However, the TSAT value needs to be read in the clinical context as TSAT has acute phase reactivity is affected by diurnal and dietary fluctuations of serum iron[37].

The following parameters may be considered as baseline laboratory investigations for the evaluation of anemia in cirrhosis. Since there are multiple pathogenic mechanisms into play, none of these parameters are specific to diagnose the cause of anemia in cirrhosis. However, each of these investigations is an important tool for initial screening as well as prognosis for the severity of the underlying liver disease.These parameters include: Hb level; White blood count (WBC) and differential cell count (DLC); Platelet count; RBC indices; Mean corpuscular volume (MCV); Absolute reticulocyte count; Serum iron studies; Serum ferritin; Transferrin saturation (TSAT);and Hepcidin.

Serum transferrin receptor

Absolute reticulocyte count and reticulocyte index (reticulocyte count which has been adjusted to the degree of anemia) is a useful screening test to ascertain the appropriate bone marrow response to anemia. An abnormal reticulocyte count along with low Hb concentration is associated with increased mortality in liver transplantation (LT)patients[19].

Folic acid, Vit B12, Vit B6

Deficiency of Vit B12, B6, and folic acid may be a contributing factor to the development of anemia in cirrhosis. European Society for Clinical Nutrition and Metabolism guidelines recommend baseline screening for Vit and micronutrients in all patients with cirrhosis[40]. However, the laboratory assays for detecting micronutrient deficiencies are not standardized for patients with cirrhosis. The various assays are Erythrocyte folate level < 140 ng/mL, plasma pyridoxal 5’ phosphate level < 20 nmol/mL, and methylmalonic acid level > 0.4 μmol/L qualify as folic acid, Vit B6 and Vit B12 deficiency respectively[41].

MANAGEMENT

Changes in erythrocyte membrane morphology and erythrocyte volume have been documented in patients with cirrhosis irrespective of the presence of anemia.Macrocytosis and normocytosis are the most frequently observed changes in cirrhosis[23]. MCV is an important investigation in the diagnosis of anemia with a high predictive value in diagnosing alcohol-related liver diseases as well as alcohol abuse.Studies have demonstrated that macrocytosis (MCV > 100 fL) was seen in 64%-84.5%of patients with alcohol consumption > 80 g/d even in the absence of anemia[24,25].Vit B 12 and folate deficiency, increased deposition of cholesterol in RBC membrane,presence of immature RBCs’ (20% larger than mature erythrocytes), may all contribute to macrocytosis in cirrhosis. In patients with hepatitis B-related decompensated cirrhosis, macrocytosis is associated with severe disease (determined by higher MELD scores) and a higher risk of death secondary to HCC[26,27].

MANAGEMENT OF A PATIENT OF ANEMIA IN CIRRHOSIS WITH ONGOING/ACUTE BLEEDING

“艾力素是我们联合美国肥必施公司共同推出的液体缓释氮肥，通过对作物精准补氮，从而保证作物在整个生长过程中供应均衡的营养，实现快速生长。”深圳市艾力农生态发展有限公司董事长助理杨明波表示。

MANAGEMENT OF A PATIENT OF ANEMIA IN CIRRHOSIS WITH NO EVIDENCE OF ACUTE/ONGOING GI BLEED

在并购的过程中，支付方式是影响收购企业的资本结构的一个重要因素，是并购双方需要重点考虑的问题。目前的支付方式主要有：现金支付、股票支付、资产置换支付、债权支付以及混合支付等方式。与此同时，中国的并购市场在进行着不断的创新，2016年2月，中国证监会以书面形式传达了未来并购重组监管的五大方向，其中之一就是“支持并购重组创新，研究并购重组支付创新方式，引入优先股和私募可交换债等方式”。由此可见，支付方式的多元化已经成为不可逆转的趋势。

MANAGEMENT OF IDA IN CIRRHOSIS

Treatment aims to provide symptomatic relief, replace iron stores and normalize RBC indices. Management of IDA secondary to acute blood loss has already been discussed in the section on ‘Management of anemia in cirrhosis with acute/ongoing GI bleed’.The efficacy of the available tests to diagnose IDA and to assess the adequacy of treatment has inherent drawbacks in patients with cirrhosis. These have been highlighted in the discussion on ‘specific investigations’ mentioned above. There are no available guidelines to manage a case of anemia in cirrhosis. Experience gained from the management of anemia in patients with chronic kidney disease (CKD),another progressive inflammatory disorder, may be utilized in patients with cirrhosis.Iron can be given as oral iron preparations (indicated for mild anemia > 11 g/dL or <10.9 g/dL but > 8 g/dL): Divalent iron salts, ferrous sulphate, ferrous gluconate and ferrous fumarate. Ferrous sulfate is the universally available form[46]. Traditionally the recommended dose in IDA is 100 -200 mg of elemental iron, preferably empty stomach, of which 10%-20% of elemental iron is absorbed. Although evidence is scarce,ascorbic acid 250-500 mg/d may be prescribed along with oral iron preparations.Treatment may be prescribed for a minimum of 3 mo to achieve adequate replacement for iron stores[47]. Oral iron preparations are associated with considerable side effects:altered metallic taste, nausea, occasional vomiting, epigastric burning sensation,constipation, or diarrhea[48]. Patients with cirrhosis may have a suboptimal response(< 1g/dL increase in Hb after 3 wk of therapy) owing to malabsorption or disease complications like hepatic encephalopathy (HE) because of constipation. Recent evidence suggests that altering the dosing schedule, the alternate-day schedule may be as effective as the traditional daily dose regimen[49]. Newer oral preparations like sucrosomial iron (SI) have been tried with efficacy similar to injectable iron in nondialysis dependent CKD patients but not in patients with cirrhosis[50].

科技成果转化是一个复杂的系统工程，不仅仅涉及高校院所和企业，还需要科技服务机构提供成果评估、科技金融、知识产权、检验检测等专业化服务，无论哪个环节出现障碍都会影响整个成果转移转化的进程，而当前江苏虽然服务机构众多，但多数的服务机构服务功能单一，所提供的服务大多仅限于“牵线搭桥”式的信息服务，具有公信力和权威性的科技成果评估机构缺乏，能够提供科技成果登记、评估、管理、许可转让管理咨询、风险投资和投融资等综合性服务的服务机构少，远不能满足高校院所、企业科技成果转移转化的需求［3］。

Failure of oral iron therapy, malabsorption, severe IDA are some of the universally accepted indications of intravenous (IV) iron therapy. Some or all of these may be present in patients of cirrhosis with IDA. IV iron preparations have different pharmacokinetics vs. oral iron preparations. Once into the bloodstream, elemental iron is taken up by macrophages and releasedferroportin thus circumventing, intestinal absorption[51]. Adverse effects can vary from minor infusion reactions (rash,palpitation, myalgia, chest discomfort) to serious anaphylactoid reactions causing respiratory or hemodynamic changes. Among the available IV iron preparations,maximum single dose that can be administered and minimum administration time are as follows: Fe gluconate: 125 mg (30-60 min), Fe-sucrose: 200 mg (30 min), Fecarboxymaltose: 1000 mg (15 min), Fe-isomaltoside: 20 mg Fe/kg (15 min),Ferumoxytol: 510 mg (15 min) respectively[48].

在小学语文的教学过程中虽然倡导以学生的学习为主体，但是教师在教学的过程中不能局限于让学生学习课本中的内容，要采取启发式的教学来培养学生的阅读能力，然后指导学生学习写作，让阅读和写作有效结合起来，互相补充。这样的教学方法能够改善学生阅读过程中遇到的障碍，更能够激发学生养成好的学习习惯，从而提高小学语文的教学质量，让学生能够更好地全面发展。

Blood transfusion (packed RBC transfusion) is generally reserved for patients who remain symptomatic despite IV iron therapy or are hemodynamically unstable. The key concept is not to target a normal Hb level but one at which iron supplementation can be safely initiated[52].

MANAGEMENT OF ANEMIA OF CHRONIC DISEASE IN PATIENTS WITH CIRRHOSIS

Two distinct yet complementary treatment strategies may be adopted while managing a patient with cirrhosis with anemia of chronic disease. The first caters to ‘silencing’the underlying disease and managing its complications. Although, LT is the only definite cure, prevention of fibrosis, cessation of alcohol, treatment for HBV and HCV,all have a role to play. The second strategy involves managing nutritional deficiencies.Thus, it is imperative to treat co-existing IDA, Vit B12, B6, or folate deficiencies[53].This also brings to light the often ignored or neglected dietary prescription in patientswith cirrhosis. Sound dietary advice especially rich in elemental iron, and other micronutrients need to be ingrained into every hospital visit by the patient. Certain treatment strategies that might be considered in future clinical trials arethiamine derivative fursultiamine: Ferroportin antagonist[54] for which the only presently approved indication is Vit B1 deficiency. Prolyl hydroxylase enzyme (PHD) inhibitors are tried in clinical trials for the management of the anemia of chronic disease especially CKD. PHD inhibitor stabilizes HIF which in turn leads to a positive effect on erythropoiesis and iron metabolism[55].

对于学界讨论体育赛事转播权时经常提到的知识产权保护路径，本文并不认同。理由除了前文提到的与版权法立法目的和体育精神不符，且体育赛事处于公有领域等理论层面的障碍之外，还有实践操作层面的问题：体育赛事转播权如果适用知识产权法的保护路径，将导致严重的利益失衡。

VIT B12, B6, AND FOLIC ACID SUPPLEMENTATION

Micronutrient deficiencies are common in patients with cirrhosis. For patients with suspected or proven folic acid deficiency IV supplementation with 0.4-4 mg of folic acid daily for 3 d followed by recommended daily allowance (RDA) of 400 μg/d is advisable. In case of suspected intestinal malabsorption IV dosage may be prolonged.Folic acid supplementation > 1 mg/d may mask Vit B12 deficiency. The RDA for Vit B6 is 1.3 mg/d for men and women 19-50 years of age, 1.5 mg and 1.7 mg for women and men > 51 years of age respectively. The recommended dosage for Vit B12 in patients with concomitant neuropsychiatric signs is 1000 μg intramuscular every alternate day for 3 wk followed by monthly 1000 μg intramuscular injections or 1000-2000 μg oral supplementation[41].

MANAGEMENT OF ANEMIA IN CIRRHOSIS: WORK IN PROGRESS

Anemia is present in 60%-75% of all patients with cirrhosis[3]. The presence of anemia and various RBC indices, serum ferritin, TSAT, have all been independently associated with worsening disease severity and poor prognosis. However, to date, there are no universally available guidelines that dwell on this common but rather difficult to treat disease manifestation. There are lacunae in our understanding of disease and its management. Furthermore, the available parameters for the diagnosis and evaluation of anemia, and the laboratory assays have not been standardized or validated in patients with cirrhosis.

IDA is a potentially treatable condition and unlike other chronic inflammatory conditions like CKD and inflammatory bowel disease, cut-off values of serum ferritin and TSAT have not been validated in cirrhosis. How do we diagnose IDA in cirrhosis?What is the best method of replacement of elemental iron in cirrhosis? Definite randomized controlled trials (RCTs) are lacking on this management aspect. The ongoing RCTs have been highlighted in Table 2. What is the protocol for diagnosing and supplementing other micronutrient deficiencies, Folic acid, Vit B12, B6 which contribute to the development of anemia in cirrhosis? When and how often to supplement and reevaluate for assessment of body stores for these micronutrients?How does one prevent or screen for iron overload, which by itself is associated with increased mortality in cirrhosis? Last but not the least, should the presence of anemia or indices like serum ferritin be incorporated into existing severity scores like MELD score to improve their prognostic accuracy? All these are areas of potential research and may help us decipher this enigma and its potential contribution to the outcome of cirrhosis!

综上所述，ASO患者介入治疗期间配合品管圈活动，提高了患者疾病治愈率以及治疗方案认知、健康教育效果以及护理人员能力。

We have proposed an algorithm for evaluation and management of anemia in cirrhosis as per available evidence (Figure 3); it will require validation and subsequent modification prospectively. More so when more research is carried out to fill the lacunae in the existing understanding of the subject.

CONCLUSION

The evaluation and management of anemia in cirrhosis is an important aspect of disease management. IDA is a potentially treatable cause of anemia wherein RBC indices and serum iron studies have prognostic significance. Patients should be screened for deficiency of micronutrients like Folic acid, Vit B12, Vit B6 at baseline and supplementation should be initiated. Future research into various aspects dealing with diagnosis, management of anemia, and newer therapeutic modalities is the need of the hour. In addition, the role of anemia in the prognostication of cirrhosis is an area that needs further research in prospective trials.