Role of the spleen in membrane conditioning and hemolysis of spur cells in liver disease

A thorny matter: Spur cell anemia

Spur cell anemia (SCA) is an acquired form of non-autoimmune hemolytic anemia that occurs in advanced liver disease. It is characterized by the presence of acanthocytes or spur cells, spiculated erythrocytes whose shortened life span causes anemia that is unresponsive to transfusion. SCA has been regarded as a rare condition with an ominous prognosis for which the only known cure is liver transplantation, but recent prospective studies have demonstrated the existence of a milder form of SCA in which there are smaller numbers of acanthocytes, but which is nevertheless associated with hemolysis and poor outcomes. This form of SCA appears to be considerably more common than the severe classical variant. The conventional understanding of the pathogenesis of SCA is that abnormalities of lipid metabolism are the primary event driving the formation of spur cells. However, the studies that underpin this theory are based on small numbers of patients with heterogeneous clinical features and inconsistent use of nomenclature for dysmorphic red blood cells. In this review, we discuss the evolution of the current understanding of SCA and therapeutic strategies that have been employed based on this understanding. Our goal is to raise awareness of this understudied condition that has significant implications for patient outcomes. Furthermore, we highlight the need for rigorous, contemporary research into the underlying cause or causes of SCA in order to develop an effective therapy for this disorder.

Predictors of mortality and outcomes of liver transplant in spur cell hemolytic anemia

Spur cell hemolytic anemia (SCHA) is a rare, acquired, nonimmune hemolytic anemia of decompensated cirrhosis. Data describing prognostic impact, outcomes of liver transplant, and clinical hematologic characteristics of SCHA are absent or limited. We performed a multicenter, 24-year observational cohort study of patients with SCHA, retrospectively analyzing hepatic and hematologic parameters, independent predictors of mortality, and long-term outcomes of liver transplant. Sixty-nine patients with SCHA met eligibility for inclusion. The median (interquartile range) age was 53 (42-59) years; 46.4% were female, and 11 (15.9%) received liver transplant. Thirty-nine patients (56.5%) were red blood celltransfusion-dependent. All 11 patients undergoing transplant had rapid and complete resolution of SCHA, with improvement in median hematocrit from 22.1% to 34.6% post-transplant (p = .001) and excellent post-transplant outcomes. In multivariable logistic models adjusting for age, sex, etiology of cirrhosis, active/recent variceal bleeding, and Child-Turcotte-Pugh score, transfusion dependence had an odds ratio (OR) for 90-day mortality of 9.14 (95% CI, 2.46-34.00) and reduced pre-transfusion hematocrit had an OR of 4.73 (95% CI, 1.42-15.82) per 6% decrease; increased red cell transfusion requirement, reduced hemoglobin, increased lactate dehydrogenase, and increased indirect bilirubin were also independently predictive of higher 90-day mortality. Model for end-stage liver disease (MELD)-Na and Child-Turcotte-Pugh scores consistently significantly underestimated 90-day mortality, with standardized mortality ratios (SMRs) >1 across all scores/classes [MELD-Na 20-29, SMR 2.42 (1.18-4.44); Child-Turcotte-Pugh class B, SMR 4.46 (1.64-9.90)]. In conclusion, SCHA is associated with substantial excess mortality than predicted by MELD-Na or Child-Turcotte-Pugh scores and uniformly resolves with liver transplant, without recurrence. Multiple parameters of hemolytic anemia severity independently predict higher 90-day mortality.

National Trends and Outcomes of Nonautoimmune Hemolytic Anemia in Alcoholic Liver Disease: Analysis of the Nationwide Inpatient Sample

GOAL

The aim of this study was to determine the burden of nonautoimmune hemolytic anemia (NAHA) in hospitalized patients with coexisting alcoholic liver disease (ALD), identify risk factors for NAHA in ALD and describe the hospitalization outcomes.

BACKGROUND

ALD can result in structural and metabolic alterations in the red-blood cell membrane leading to premature destruction of erythrocytes and hemolytic anemia of varying severity.

STUDY

Hospitalized ALD patients with concomitant NAHA were identified in the Nationwide Inpatient Sample database using International Classification of Diseases-9 codes from 2009 to 2014. The primary outcome was to determine the nationwide prevalence and risk factors of NAHA in patients hospitalized with ALD.

RESULTS

The prevalence of NAHA was 0.17% (n=3585) among all ALD patients (n=2,125,311) that were hospitalized. Multivariate analysis indicated higher odds of NAHA in ALD patients in the following groups: female gender [adjusted odds ratio (AOR) AOR 1.80, P<0.0001]; highest quartile of median household income (AOR 1.88, P<0.0001); increasing Charlson-Deyo Comorbidity Index (3 to 4 vs. 0, AOR 2.16, P=0.0042) and cirrhosis (AOR 2.74, P<0.0001). Discharges of ALD with anemia had a significantly longer average length of stay (8.8 vs. 6.0 d, P<0.0001), increased hospital charges ($38,961 vs. $25,244, P<0.0001) and higher mortality (9.0% vs. 5.6%, P<0.0001) when compared with ALD with no anemia.

CONCLUSION

NAHA in patients with ALD is an important prognostic marker, predicting a longer, costlier hospitalization and increased inpatient mortality in ALD.

Erythrocyte viscoelastic recovery after liver transplantation in a cirrhotic patient affected by spur cell anaemia

In physiological conditions, red blood cells (RBCs) are capable of dramatic deformations when passing through the microvasculature. This extreme deformability is closely related to the RBC biconcave shape, to the fluidic nature of the haemoglobin and the cell membrane structure, primarily consisting of a phospholipid bilayer with an underlying two-dimensional spectrin network. In many pathological and inflammatory conditions, the shape and the extreme deformability of erythrocytes appear to be significantly altered. These findings have stimulated intense research towards the search and validation of novel erythrocyte-based mechanical biomarkers, useful for disease diagnosis and therapy monitoring. In this study, we investigated with Atomic Force Microscopy (AFM) the mechanical properties of erythrocytes obtained from a 68 years old cirrhotic man diagnosed with spur cell anaemia and cold agglutinated disease, before and after liver transplantation. Mechanical changes are compared with ultrastructural alterations as studied by scanning electron microscopy and discussed according to confocal fluorescence microscopy results, showing possible alterations induced by the cirrhotic environment at the level of the RBCs cytoskeletal organisation and lipidic composition. Taken together, the results here presented show that liver transplantation not only contributes to restoring the proper RBC morphology, but it also induces recovery of the physiological viscous behaviour of cells, further stressing the relevance of viscous and dissipative forces in determining the RBC biomechanical response.

High-dose steroids as a therapeutic option in the management of spur cell haemolytic anaemia

Spur cell haemolytic anaemia (SCA) is a form of anaemia that can be seen in patients with severely impaired liver function or advanced cirrhosis. It is associated with high mortality. The treatment options for SCA secondary to cirrhosis are limited. Our patient is a middle-aged man who developed SCA and was not a candidate for liver transplantation or splenectomy. High-dose steroids helped ameliorate haemolysis and improve anaemia and general condition of our patient.

Hyperbilirubinaemia and haemolytic anaemia in acute alcoholic hepatitis: there's oil in them thar veins

A Caucasian woman in her late 30s was evaluated after a period of binge drinking and found to have hyperbilirubinaemia for which she was referred for consideration of cholecystectomy. After exclusion of other possibilities, Zieve's syndrome was diagnosed. This is a condition of hyperbilirubinaemia, Coombs' negative haemolytic anaemia and hyperlipidaemia associated with alcoholism. Abstinence from alcohol remains the only known effective treatment, and appreciation of the entity can prevent unnecessary biliary procedures. The patient improved with supportive measures and was discharged in stable condition.

Presence of spur cells as a highly predictive factor of mortality in patients with cirrhosis

BACKGROUND AND AIM

The presence of spur-cell anemia (SCA) is due to lipid disturbances of the erythrocyte membrane and may develop in patients with advanced liver cirrhosis. The accurate predicting value of SC for survival has not been clarified. The aim of this study was to evaluate SCA as a prognostic indicator in patients with cirrhosis.

METHODS

We prospectively evaluated clinical, laboratory parameters, and survival in patients with cirrhosis, with or without SCA, during the period 2008-2011. Patients who had at admission renal failure, other causes of hemolytic anemia, hepatocellular carcinoma, sepsis, and/or active bleeding, were excluded. One hundred sixteen patients with cirrhosis were included. The presence of SCA (SC rate higher or equal to 5% [≥ 5%]) was diagnosed in 36 (31%) patients.

RESULTS

Patients with SCA compared to those without had more advanced liver disease (higher Model for End-Stage Liver Disease [MELD], P < 0.001), higher total bilirubin (P < 0.001), and International Normalized Ratio (P < 0.001). Patients with SCA had worse survival (log rank P < 0.001). Survival of patients with SCA at the first, second, and third month of follow-up was 77%, 45%, and 33%, respectively. In multivariate Cox's regression analysis, the presence of SCA was an independent predictor of mortality (hazard ratio = 3.17 [95% CI 1.55-6.48]).

CONCLUSIONS

The presence of spur-cell anemia is not uncommon in cirrhosis and seems to be strongly associated with mortality. SCA can be used in combination with MELD as an additional predictor of early mortality.

The cholesterol content of the erythrocyte membrane is an important determinant of phosphatidylserine exposure

Maintenance of the asymmetric distribution of phospholipids across the plasma membrane is a prerequisite for the survival of erythrocytes. Various stimuli have been shown to induce scrambling of phospholipids and thereby exposure of phosphatidylserine (PS). In two types of patients, both with aberrant plasma cholesterol levels, we observed an aberrant PS exposure in erythrocytes upon stimulation. We investigated the effect of high and low levels of cholesterol on the ATP-dependent flippase, which maintains phospholipid asymmetry, and the ATP-independent scrambling activity, which breaks down phospholipid asymmetry. We analyzed erythrocytes of a patient with spur cell anemia, characterized by elevated plasma cholesterol, and the erythrocytes of Tangier disease patients with very low levels of plasma cholesterol. In normal erythrocytes, loaded with cholesterol or depleted of cholesterol in vitro, the same analyses were performed. Changes in the cholesterol/phospholipid ratio of erythrocytes had marked effects on PS exposure upon cell activation. Excess cholesterol profoundly inhibited PS exposure, whereas cholesterol depletion led to increased PS exposure. The activity of the ATP-dependent flippase was not changed, suggesting a major influence of cholesterol on the outward translocation of PS. The effects of cholesterol were not accompanied by eminent changes in cytoskeletal and membrane proteins. These findings emphasize the importance of cholesterol exchange between circulating plasma and the erythrocyte membrane as determinant for phosphatidylserine exposure in erythrocytes.

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.

Alcohol induced burr cell (echinocytic) haemolytic anaemia and haemochromatosis

A 51-year-old man with chronic alcoholic liver disease developed a severe haemolytic anaemia characterized by the presence of circulating burr-shaped cells (echinocytes). Several transfusions of packed red cells were ineffective in raising the haemoglobin concentration, showing that the abnormality was acquired by the transfused cells. Liver biopsies revealed haemochromatosis. Haematological parameters normalized four months after the patient stopped drinking alcohol, but burr cells were still present and erythrocyte life-span was still markedly shortened at one year follow-up. Since serum cholesterol, HDL-cholesterol, and Apo-AI and Apo-B lipoproteins were considerably decreased, the lipid composition of the red cell membrane was studied. Findings showed that echinocytosis occurred with no change in membrane cholesterol content, nor in cholesterol:phospholipid ratio, but with an alteration in the phosphatidylserine and phosphatidylinositol concentrations. While haemochromatosis was most likely the cause of the erythrocyte anomaly, alcohol intake was probably responsible for the acute onset of haemolytic anaemia with effects directly on the erythrocyte membrane as well as mediated by the progressive hepatic injury, with alterations in the plasma and successively in the intramembrane lipid composition.

Influence of the spleen on the expression of surface antigens on parasitized erythrocytes

Two malaria parasites, Plasmodium knowlesi and P. falciparum, when passaged in splenectomized hosts alter or fail to express parasite-dependent antigens on the surface membrane of erythrocytes infected with mature parasites. Experiments with cloned populations of P.knowlesi show this change to be phenotypic and to be modulated by the spleen of the host. In addition, the induction of antigen variation in P. knowlesi malaria apparently requires two factors: specific antibody and the spleen. Along with the altered expression of P. knowlesi variant antigen on the infected erythrocyte surface, there is a decrease in parasite virulence in non-splenectomized monkeys. It is suggested that the spleen-dependent expression of malarial antigens on the parasitized erythrocyte may be an adaptation of the malaria parasite for survival in the presence of a potentially destructive spleen-mediated host immunity.

Spur cell anemia associated with a cirrhotic non-alcoholic steatohepatitis patient

Spur cell anemia is an acquired hemolytic anemia, which may occur in patients with severe liver dysfunction, especially in those with alcoholic cirrhosis. Recently, non-alcoholic steatohepatitis (NASH) has been highlighted as one of the causes of chronic liver diseases, which could progress to cirrhosis. Histological features of NASH are indistinguishable from those of alcoholic hepatitis. We report on a cirrhotic NASH patient who developed progressive indirect dominant jaundice and intractable hemolytic anemia during his follow-up. This report shows the first case of a cirrhotic NASH patient who died as a result of spur cell anemia.

Echinocytosis--an unusual manifestation of hemangioma

The case of a 21 year-old female with echinocytosis and a littoral cell hemangioma is reported. The patient had no significant past medical history and presented with abdominal pain and splenomegaly. A large percentage of echinocytes were noted on her peripheral smear in the absence of any known causes. A CT-recognized splenic mass led to splenectomy and a benign hemangioma was found. Red blood cell abnormalities resolved immediately after the surgery. This is the first case reported in the literature of echinocytosis as a consequence of a hemangioma.

Peroxidative stress and antioxidant enzymes in children with beta-thalassemia major

OBJECTIVE

Regular blood transfusions and secondary iron overload make thalassemic erythrocytes prone to peroxidative injury. Although some reports suggest endogenous free radical damage in thalassemia, there remains discrepancy in the status of antioxidant enzymes. The aim of this study was to evaluate the extent of lipid peroxidation and status of antioxidant enzyme in children with beta-thalassemia.

METHODS

Fifty transfusion-dependent beta-thalassemics were subjected to analysis of lipoperoxides as malondialdehyde (MDA), nitric oxide (NOx), superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GPx) along with serum iron and ferritin, liver functions and uric acid. Plasma MDA was analyzed to indicate the oxidative parameters, whereas the erythrocyte SOD, GPx, and plasma NOx were measured to show the antioxidant status of the children. All these parameters in 30 non-anemic healthy controls attending the child health promotion clinic of hospital were also studied.

RESULTS

All the patients were iron overloaded. Markers of free radical injury such as MDA and antioxidant enzyme SOD and NOx levels were significantly elevated in thalassemic children while mean GPx levels were decreased in patients compared to controls (P < 0.001). All these markers significantly correlated with serum ferritin levels. There was no significant difference in levels of GSH measured but it correlated with serum iron levels.

CONCLUSION

Our study results suggest that iron overload causes peroxidative damage in beta-thalassemia and antioxidant systems try to compensate for reducing lipid peroxidation to lower tissue damage.

Red blood cell status in alcoholic and non-alcoholic liver disease

Macrocytosis is most commonly associated with vitamin B(12) and folic acid deficiency, followed by alcoholism, liver disease, and other pathologic conditions. We studied the red cell and vitamin status in 423 consecutive patients with various liver diseases, including 31 with acute viral hepatitis (AVH), 105 with chronic hepatitis (CH), and 134 with alcoholic liver disease (ALD), who consisted of 84 with non-cirrhotic alcoholic liver disease (NCALD) and 50 with alcoholic liver cirrhosis (ALC), 60 with non-alcoholic liver cirrhosis (NALC), and 93 with hepatocellular carcinoma (HCC). The mean corpuscular volume (MCV) and red cell distribution width (RDW) were significantly higher in patients with ALD and NALC, and among them macrocytosis occurred more frequently in patients with ALC. Macrocytic anemia was mostly found in cirrhotic patients, in which the Child-Pugh score was closely related to the development of macrocytic anemia. In ALD, the MCV was significantly correlated with the estimated alcohol consumption and inversely correlated with the serum folic acid level, which, however, was often maintained within the normal range in patients with macrocytic ALC. After abstinence from alcohol, the MCV and RDW were reduced significantly and were associated with an increasing serum folic acid level. This suggests that macrocytic anemia was a common feature of alcoholic and non-alcoholic liver cirrhosis and that alcohol abuse and folic acid deficiency play a secondary role in macrocytosis.

Successful combination therapy--flunarizine, pentoxifylline, and cholestyramine--for spur cell anemia

Spur cell anemia, a hemolytic anemia observed in patients with alcoholic cirrhosis, is characterized by unusual erythrocyte morphology and an increased ratio of free cholesterol to phospholipid in the erythrocyte membrane. The prognosis of spur cell anemia is usually extremely poor, however, we describe here a patient with spur cell anemia who was successfully treated with combination therapy consisting of flunarizine, pentoxifylline, and cholestyramine. Initial therapy with flunarizine alone for 6 weeks did not significantly decrease the number of spur cells on peripheral blood smears. So pentoxifylline was added to the regimen. The patient recovered from the anemia, showed remarkable improvement with regard to the hyperbilirubinemia, and the changes were accompanied by a significant decrease in the number of spur cells in peripheral blood smears. To correct the hypercholesterolemia, cholestyramine was added to the regimen, which resulted in a reduction in the serum level of free cholesterol and an increase in the molar ratio of free cholesterol to phospholipid in erythrocyte membrane. However, 6 months later a skin eruption developed that was considered an adverse reaction to the drugs, so the flunarizine and pentoxifylline were discontinued. With cholestyramine therapy alone, the remission of spur cell anemia was maintained for more than 11 months. These observations suggest that non-invasive combination therapy with flunarizine, pentoxifylline, and cholestyramine is effective and valuable in the treatment of patients with spur cell anemia.

Increased hepatic iron and cirrhosis: no evidence for an adverse effect on patient outcome following liver transplantation

It has been suggested that preexisting severe hepatic iron overload may adversely affect outcome after liver transplantation. The pathogenesis of iron overload in cirrhosis in the absence of hemochromatosis gene (HFE) mutations is poorly understood. The relationships between liver disease severity and etiology, degree of hepatic iron overload, and post-liver transplantation outcome were studied in 282 consecutive adult patients with cirrhosis. Thirty-seven percent of patients had stainable hepatic iron. Increased hepatic iron concentration was significantly associated with more severe liver disease (P<.001), male sex (P = .05), the presence of spur cell anemia (P<.0001), and hepatocellular liver disease (P<.0001). The HFE mutations were uncommon in patients with increased hepatic iron stores. Increased hepatic iron concentration was not associated with greater utilization of resources or a lower survival after liver transplantation. Child-Pugh score at the time of liver transplantation was the only independent variable affecting patient survival (P = .0008). In summary, our data suggest that the severity of the liver disease rather than hepatic iron concentration is the most important determinant of outcome after liver transplantation and that, in general, increasing hepatic iron concentration in cirrhosis is a surrogate marker of the severity of the underlying liver disease.

Resolution of spur cell anemia with liver transplantation: a case report and review of the literature

Spur cell anemia is an acquired hemolytic anemia, characterized by an increased percentage of abnormally shaped erythrocytes that are known as acanthocytes. The erythrocytes have numerous spicules irregularly distributed over the cell surface. Spur cell anemia has been described to occur in several conditions, including cirrhosis. We present an unusual case of a young patient with hemochromatosis, alcohol abuse, decompensated cirrhosis, and spur cell anemia who had a spontaneous resolution of the spur cell anemia after orthotopic liver transplantation. This finding suggests that the diseased liver may contribute to transformation of the erythrocyte to the spur cell.

Mechanisms of hemolysis and anemia associated with acute antepartum pyelonephritis

Anemia develops in about a fourth of women whose pregnancy is complicated by pyelonephritis, although its exact mechanism has not been defined clearly. In this study of 18 women with antepartum pyelonephritis, although only a third had anemia (hematocrit less than 30 vol/dl), there was evidence for hemolysis in all 18. Specifically there was a mean decrease in hematocrit of 5 vol/dl from admission to discharge. With scanning electron microscopy, we compared erythrocyte morphologic aberrations that were found in women with renal infection with those of normally pregnant women, and the former had significantly increased proportions of echinocytes in particular, but schistocytes and spherocytes were increased also (total 10.3% vs 1.4%, p less than 0.0001). These changes, especially echinocytosis, have been induced in vitro by lipopolysaccharide, and they are known to lead to premature red blood cell destruction in vivo. We conclude that hemolysis with subsequent anemia in pregnant women with pyelonephritis is caused by lipopolysaccharide-induced red blood cell membrane damage.

Increased proteolytic activity of erythrocyte membrane in spur cell anaemia

In a case of 'spur cell anaemia' (SCA) a reduced esterified/free cholesterol ratio was found in plasma, in LDL and HDL fractions and an increased cholesterol/phospholipid (C/PL) molar ratio in erythrocyte membrane. Cation transport was normal with the exception of Li-Na counter-transport was decreased. An increased intrinsic membrane proteolytic activity (IMPA) was demonstrated by the generalized reduction or, sometimes, disappearance of protein bands on SDS-PAGE in patient ghosts when the proteolysis was allowed. This characteristic was found to be transferable to normal cells by incubation in SCA-plasma; moreover membrane C/PL molar ratio was augmented after incubation. Normal plasma was not able to normalize IMPA of SCA cells 'in vitro', even if it induced a remarkable decrease of membrane C/PL molar ratio. Nevertheless IMPA normalization did occur 'in vivo', when the SCA cells were exposed to therapeutic 'plasma exchange' (3.3 litre/week). The results suggest the following conclusions: (a) in our SCA patient there is an increased IMPA; (b) this feature, as well as membrane lipid alteration, is transferable to normal erythrocytes; (c) this case seems to demonstrate, for the first time in our knowledge, a modulating effect of plasma on IMPA in erythrocytes.

Red blood cell membrane microviscosity correlates with posttransfusion survival

The cholesterol/phospholipid and sphingomyelin/phospholipid ratios of red blood cells stored for 42 days were unchanged after storage. However, the total phospholipid concentration in the red cells decreased suggesting a loss of red cell membrane during storage. The 24 h survival of the stored red cells was assessed by the Cr technique in homologous donors. A decrease in fluorescence polarization of diphenylhexatriene incorporated into the membrane was observed following storage which correlated with survival. Thus, molecular defects in the lipid bilayer are associated with long-term storage of red blood cells.

Compensatory mechanisms in erythrocyte lipids in patients with atherosclerosis

The quantitative composition of phospholipids and fatty acids of erythrocytes was investigated in patients with atherosclerosis. It was stated that the erythrocyte lipids of atherosclerotic patients contained smaller quantities of phosphatidylcholine and phosphatidylinositol, a significantly larger quantity of sphingomyelin, and higher sphingomyelin/phosphatidylcholine and cholesterol/phospholipid ratios. The existence of compensatory changes was stated, which was evident in the reduction of palmitic and stearic acids and the increase of linoleic and eicosatrienoic acids in erythrocyte phospholipids. These changes in fatty acid composition probably cause minimal changes in the membrane fluidity induced by an increased cholesterol/phospholipid and sphingomyelin/phosphatidylcholine ratios. This paper was the first evidence of occurrence of those changes in erythrocytes during spontaneous atherosclerosis in human.

Spur cell anemia (acanthocytosis) complicating idiopathic hemochromatosis

A 65-year-old male developed a rapidly progressive disease characterized by severe hemolysis, with spur cells (acanthocytes) and liver disease. Autopsy findings were consistent with a diagnosis of idiopathic hemochromatosis. Investigation of the patient's family uncovered four out of five first degree relatives with significantly raised serum ferritin levels. A sister had biopsy proven hemochromatosis. Spur cell anemia is a recognized, though rare, complication of alcoholic liver disease and indeed the patient had a regular alcohol intake of up to 50 g daily. Although the alcohol intake could have contributed to the formation of spur cells, the possible association with hemochromatosis should be considered. A diagnosis of hemochromatosis has important implications for family members.

Erythrocyte echinocytosis in liver disease. Role of abnormal plasma high density lipoproteins

Echinocytes were frequently found in patients with liver disease when their blood was examined in wet films, but rarely detected in dried, stained smears. When normal erythrocytes (discocytes) were incubated with physiologic concentrations of the abnormal high density lipoproteins (HDL) from some jaundiced patients, echinocytosis developed within seconds. Other plasma fractions were not echinocytogenic. There was a close correlation between the number of echinocytes found in vivo and the ability of the corresponding HDL to induce discocyte-echinocyte transformation. On incubation with normal HDL, echinocytes generated in vitro rapidly reverted to a normal shape, and echinocytes from patients showed a similar trend. Echinocytosis occurred without change in membrane cholesterol content, as did its reversal, and was not caused by membrane uptake of lysolecithin or bile acids. Abnormal, echinocytogenic HDL showed saturable binding to approximately 5,000 sites per normal erythrocyte with an association constant of 10(8) M-1. Nonechinocytogenic patient HDL and normal HDL showed only nonsaturable binding. Several minor components of electrophoretically separated erythrocyte membrane proteins bound the abnormal HDL; pretreatment of the cells with trypsin or pronase reduced or eliminated binding. Echinocytosis by abnormal HDL required receptor occupancy, rather than transfer of constituents to or from the membrane, because cells reversibly prefixed in the discoid shape by wheat germ agglutinin, and then exposed to abnormal HDL, did not become echinocytes when the HDL and lectin were successively removed. Binding did not cause dephosphorylation of spectrin. We conclude that the echinocytes of liver disease are generated from discocytes by abnormal HDL, and we infer that the shape change is mediated by cell-surface receptors for abnormal HDL molecules.

Modification of the erythrocyte membrane by a non-specific lipid transfer protein

The non-specific phospholipid transfer protein purified from bovine liver has been used to modify the phospholipid content and phospholipid composition of the membrane of intact human erythrocytes. Apart from an exchange of phosphatidylcholine between the red cell and PC-containing vesicles, the protein appeared to facilitate net transfer of phosphatidylcholine from the donor vesicles to the erythrocyte and sphingomyelin transfer in the opposite direction. Phosphatidylcholine transfer was accompanied by an equivalent transfer (on a molar basis) of cholesterol. An increase in phosphatidylcholine content in the erythrocyte membrane from 90 to 282 nmol per 100 microliters packed cells was observed. Phospholipase C treatment of modified cells showed that all of the phosphatidylcholine which was transferred to the erythrocyte was incorporated in the lipid bilayer. The nonspecific lipid transfer protein used here appeared to be a suitable tool to modify lipid content and composition of the erythrocyte membrane, and possible applications of this approach are discussed.

Diurnal patterns of the concentrations of cholesterol, triglycerides, glucose, nonprotein nitrogen and urea in the serum of veal calves fed a milk replacer supplemented with cholesterol

Veal calves (aged about 9 weeks; three animals per group) were fed twice a day liquid diets containing 60% skim milk powder and 20% crude fat (w/w) for 7.5 weeks. Addition of 1% cholesterol to the diet, at the expense of fat, caused a 70% increase in the level of serum cholesterol. Both in the control and cholesterol-fed calves, no diurnal rhythm in the concentration of cholesterol in the serum was observed. Serum triglycerides were not clearly elevated after feeding, but a steady increase during the day was observed, the increase being similar in both dietary groups. Cholesterol feeding seemed to induce lower postprandial levels of urea and higher levels of amino acid nitrogen, but this was only observed after feeding in the morning (8.00 a.m.), but not after feeding in the evening (8.00 p.m.). Dietary cholesterol significantly elevated postprandial glucose levels in veal calves. It is suggested that hypercholesterolemia effects an impaired glucose tolerance, possibly also in man.

Mechanism of increased osmotic resistance of red cells in workers exposed to lead

In order to clarify the mechanism of the increased osmotic resistance of red blood cells in lead workers 19 men employed in a lead refining factory and 18 control male workers employed in railway construction were examined for red cell count, haematocrit, MCV, blood and urine lead concentrations, urine coproporphyrin and delta-aminolevulinic acid, osmotic resistance of red cells, lecithin-cholesterol acyltransferase (LCAT) activity in serum, and cholesterol content and cholesterol-to-phospholipid ratio of the red cell membrane. The results were: (1) The osmotic resistance of the red cells (p less than 0.05), cholesterol content of the red cell membrane, blood and urine lead, urine coproporphyrin, and urine delta-ALA concentrations (p less than 0.01) were higher in the lead workers than in the controls. (2) In the lead workers close relationships were observed between the osmotic resistance and the blood lead concentration (r = -0.515, p less than 0.05), osmotic resistance and LCAT activity (r = 0.596, p less than 0.01), and osmotic resistance and cholesterol of the red cell membrane (r = -0.492, p less than 0.05).

Alterations of lipids of the erythrocyte membranes in workers exposed to lead

Changes in lipids (cholesterol and phospholipids) of the erythrocyte membrane were studied and several laboratory examinations were performed with 25 male workers employed in a scrap lead refining factory using as controls 38 male railway construction workers. The examinations included measurements of erythrocyte count, hematocrit, mean corpuscular volume (MCV), blood and urine lead concentrations, urine coproporphyrin and delta-aminolevulinic acid, membrane cholesterol (CHO) and phospholipids (PL), total and free CHO in plasma, and lecithin cholesterol acyltransferase (LCAT) activity in plasma. The results were: 1) Membrane CHO (P less than 0.01) and CHO: PL ratio (P less than 0.05) of lead workers were higher than those of the controls. But no significant difference was observed in membrane PL between both groups. 2) Membrane phosphatidyl choline was higher (P less than 0.05) and lysophosphatidyl choline was lower (P less than 0.05) in lead workers compared with controls. But no significant difference was observed in membrane sphingomyelin, phosphatidyl serine, and phosphatidyl ethanolamine between both groups. 3) Free CHO in plasma was higher (P less than 0.05) in lead workers compared with controls. But no significant difference was observed in total CHO in plasma, erythrocyte count, hematocrit, MCV, and LCAT activity between both groups.

Hereditary elliptocytosis: morphologic abnormalities during acute hepatitis

A 10-year-old black girl with hereditary elliptocytosis had a transient increase in hemolysis and unusual red cell morphologic changes during an episode of acute hepatitis. Changes in membrane lipids of these elliptocytes with defective membrane skeletal protein and abnormal distribution of cholesterol may be responsible for this phenomenon.

Studies on osmotic fragility of red blood cells determined with a coil planet centrifuge for workers occupationally exposed to lead

In order to clarify the relationship between lead exposure level and osmotic fragility of red blood cells determined by the coil planet centrifuge method, several clinical laboratory examinations were performed on 27 male workers employed in a scrap lead refining factory using as controls 40 male workers employed in railway construction. The examinations included measurement of red blood cell and reticulocyte counts, hematocrit, MCV, blood and urine lead concentrations, urine coproporphyrin, and urine delta-aminolevulinic acid. The results were: 1. Osmotic fragility of red blood cells was lower in lead workers at all three hemolytic points compared with the controls. Significant difference was observed in hemolysis of the maximum point (P less than 0.05). 2. The red blood cell and reticulocyte counts, hematocrit value and MCV of the lead workers were not significantly different from those of the controls. Values for blood and urine lead, coproporphyrin, and delta-aminolevulinic acid of the lead workers were much higher than those of the controls (P less than 0.01). 3. In lead workers, close relationships between the osmotic fragility and these laboratory findings were observed: blood lead, r = -0.572, P less than 0.01; coproporphyrin, r = -0.608, P less than 0.01; delta-aminolevulinic acid, r = -0.559, P less than 0.01; urine lead, r = -0.453, P less than 0.05.

Vascular pathways in nonsinusal red pulp--an electron microscope study of the cat spleen

The red pulp of the cat spleen, including terminal segments of arterial capillaries, pulp venules, and the reticular meshwork, was studied by transmission electron microscopy. Splenic congestion and contraction were produced by barbiturate anesthetic and norepinephrine. Terminal segments of arterial capillaries were ampullary and flared. Blood escaped into surrounding pulp spaces through interendothelial gaps. Pulp venules originated as open-ended vessels in the reticular meshwork near trabeculae and drained into trabecular veins. Venule walls were thin and composed of squamous endothelial cells, a continuous basement membrane, and reticular cells. Venules in congested spleens had many mural apertures, but venules in contracted spleens had few. The interstices of the reticular meshwork in congested spleens contained large amounts of blood, which often was concentrated, many macrophages, lymphocytes, and plasma cells. Fewer blood cells and scant plasma were present in contracted spleens. The vascular arrangements are anatomically open. Blood takes pathways through the reticular meshwork from arterial terminations to pulp venules. Some pathways through the reticular meshwork probably function as closed vascular channels conveying rapidly flowing blood. Other pathways are functionally open and probably contain slowly moving blood that constitutes a reservoir of red cells. Macrophages formed associations with mature red cells and with reticulocytes. Mature red cells were attached to macrophages in a manner indicating erythrophagocytosis. Reticulocyte attachment had a different appearance and likely resulted in reticulocyte sequestration. Platelets bore pseudopodia which would impede their passage through irregular and cell-filled pulp spaces. The change in platelet shape probably is responsible for the formation of the splenic pool of platelets.

Changes in shape of erythrocytes in rabbits on atherogenic diet and onion extracts

The effects of administration of cholesterol alone and of cholesterol and fresh whole onion extract, on the shape of erythrocytes, were studied in albino rabbits. In animals on a cholesterol-enriched diet, the erythrocytes changed shape and showed an increased tendency to aggregate, whereas they retained their normal appearance in animals on cholesterol and onion extract, and did not differ from those of normal control rabbits.

The effect of copper on erythrocyte deformability: a possible mechanism of hemolysis in acute copper intoxication

Although the development of hemolytic anemia as a complication of acute copper intoxication is well documented, the precise mechanism by which copper produces accelerated erythrocyte destruction is unknown. Normal erythrocyte survival depends in part on the ability of the cell to deform and pass through narrow areas of microcirculation in the liver and especially in the spleen. In the present study, it is demonstrated that toxic concentrations of copper rapidly and markedly reduce erythrocyte deformability. This reduction in cell deformability is associated with a marked increase in membrane permeability and osmotic fragility of copper-treated cells. Further, the decrease in deformability occurs despite normal levels of cell ATP and the apparent absence of oxidative damage to the cell. These observations indicate that copper-mediated changes in the erythrocyte membrane may be responsible for reducing the flexibility of the cell. The loss of deformability could act to reduce erythrocyte survival and thus explain the hemolysis associated with copper intoxication in vivo.

Membrane lipid composition of red blood cells in liver disease: regression of spur cell anaemia after infusion of polyunsaturated phosphatidylcholine

The morphology of red blood cells was studied in 30 patients with severe liver cirrhosis, in 10 patients with extrahepatic jaundice, and in 10 control subjects. In all the patients with extrahepatic jaundice more than 30% of red blood cells were target cells with increased resistance to osmotic lysis. In 12 patients with liver cirrhosis more than 30% of red blood cells were spur cells. The cholesterol: phospholipids (C/PL) molar ratio was 0.89 in target cells, 1.33 in spur cells, and 0.74 in normal red blood cells. The red blood cell membrane cholesterol and phospholipids exchanged with plasma lipoproteins, the lipid composition of which was studied in eight patients with spur cells; the free cholesterol: phospholipid (FC/PL) molar ratio was 0.33 (0.16 in the controls) in high density lipoproteins (HDL) and 1.40 (0.82 in the controls) in low density lipoproteins (LDL); in these patients the polyunsaturated fatty acid content was low in both phospholipids and cholesterol esters of lipoproteins. The irregular folds of the spur cells regressed when polyunsaturated lecithin was infused (2 g daily for five days) in eight patients with spur cell anaemia; the infusions decreased both C/PL ratio in RC to 0.88 and the concentration of unconjugated bilirubin (104.3 to 82.0 mumol/l (6.1 to 4.8 mg%)), whereas the activity of the plasma lecithin:cholesterol acyltransferase (LCAT) increased from 31.2 to 54.4 mumol/l/h. Polyunsaturated fatty acid content of RC lecithin increased after the infusion as it did in HDL, the FC/PL ratio of which decreased to 0.23.

Erythrocyte populations in pyruvate kinase deficiency anaemia following splenectomy. I. Cell morphology

Light and scanning electron microscopic examination of fresh erythrocytes from the blood of four patients splenectomized for severe pyruvate kinase (PK) deficiency haemolytic anaemia has revealed three morphologically different cell populations. Most striking in these patients was the presence of crenated red cells (30-50% of total) which fit current criteria for definition as echinocytes, but also with unusual surface retraction compatible with the existence of intracellular shrinkage, a phenomenon known to occur after incubation of PK deficient red cells in vitro. Additional cell types include immature reticulocytes (7-8% of total) and thin macrocytic discocytes (45-65% of total) none of which are considered specific for the disease. These morphological findings are in sharp contrast with the paucity of red cell shape abnormalities usually described in PK deficient patients before splenectomy and may provide insight into the mechanisms leading to accelerated erythrocyte destruction in this disease.

[Alcohol-related disturbances in haematopoiesis (author's transl)]

Alcohol-related disturbances are seen against the three blood cell systems. They appear after important alcohol consumption within few days and are independent from the existence of liver cirrhosis with splenomegaly. They are promptly and completely reversible after interruption of alcohol supply. Disturbances in erythropoiesis are manifested in bone marrow with megaloblasts, ring sideroblasts, and vacuoles in cytoplasma and nucleus of nucleated red cells. They are caused by folate deficiency and by perturbations of iron utilization, which is perhaps connected with impaired heme synthesis following pyridoxal phosphate deficiency. Serum iron generally increases during alcohol consumption and decreases in the following alcohol-free period. The anemia may be macrocytic and normochromic or dimorphic with hypochromic microcytes. Anemias of hard alcohol drinkers are observed also as consequence of bleeding or hemolysis of different causes. The lability against infections of drinkers is associated with changes in granulopoiesis. The most important findings are granulocytopenia, vacuoles in the immature marrow cells, perturbations in granulopoietic maturation, and decrease of marrow response. Frequently, alcohol drinkers demonstrate thrombocytopenia which is caused by ineffective thrombopoiesis and by shortened life span of platelets as direct effect of ethanol. Functional impairments of thrombocytes have been published, too.

Influence of increased membrane cholesterol on membrane fluidity and cell function in human red blood cells

Cholesterol and phospholipid are the two major lipids of the red cell membrane. Cholesterol is insoluble in water but is solubilized by phospholipids both in membranes and in plasma lipoproteins. Morever, cholesterol exchanges between membranes and lipoproteins. An equilibrium partition is established based on the amount of cholesterol relative to phospholipid (C/PL) in these two compartments. Increases in the C/PL of red cell membranes have been studied under three conditions: First, spontaneous increases in vivo have been observed in the spur red cells of patients with severe liver disease; second, similar red cell changes in vivo have been induced by the administration of cholesterol-enriched diets to rodents and dogs; third, increases in membrane cholesterol have been induced in vitro by enriching the C/PL of the lipoprotein environment with cholesterol-phospholipid dispersions (liposomes) having a C/PL of greater than 1.0. In each case, there is a close relationship between the C/PL of the plasma environment and the C/PL of the red cell membrane. In vivo, the C/PL mole ratio of red cell membranes ranges from a normal value of 0.09--1.0 to values which approach but do not reach 2.0. In vitro, this ratio approaches 3.0. Cholesterol enrichment of red cell membranes directly influences membrane lipid fluidity, as assessed by the rotational diffusion of hydrophobic fluorescent probes such as diphenyl hexatriene (DPH). A close correlation exists between increases in red cell membrane C/PL and decreases in membrane fluidity over the range of membrane C/PL from 1.0 to 2.0; however, little further change in fluidity occurs when membrane C/PL is increased to 2.0--3.0. Cholesterol enrichment of red cell membranes is associated with the transformation of cell contour to one which is redundant and folded, and this is associated with a decrease in red cell filterability in vitro. Circulation in vivo in the presence of the spleen further modifies cell shape to a spiny, irregular (spur) form, and the survival of cholesterol-rich red cells is decreased in the presence of the spleen. Although active Na-K transport is not influenced by cholesterol enrichment of human red cells, several carrier-mediated transport pathways are inhibited. We have demonstrated this effect for the cotransport of Na + K and similar results have been obtained by others in studies of organic acid transport and the transport of small neutral molecules such as erythritol and glycerol. Thus, red cell membrane C/PL is sensitive to the C/PL of the plasma environment. Increasing membrane C/PL causes a decrease in membrane fluidity, and these changes are associated with a reduction in membrane permeability, a distortion of cell contour and filterability and a shortening of the survival of red cells in vivo.