A novel method for calculating mean erythrocyte age using erythrocyte creatine

Estimating the lifespan of erythrocytes is useful for the differential diagnosis of anemia. However, measuring the lifespan of erythrocytes was very difficult; therefore, it was seldom measured. Erythrocyte creatine (EC) decreases reflecting erythrocyte age. We developed a method to obtain mean erythrocyte age (MRBC) from EC.We reanalyzed the previously published data from 21 patients with hemolytic anemia, which included EC and the half-life of 51Cr.MRBC and loge EC showed excellent significant linearity (r = -0.9475, p < 0.001), proving that it could be treated as a mono-exponential relationship within the studied range (EC: 1.45 - 11.76 μmol/g Hb). We established an equation to obtain MRBC (days) from EC (μmol/g Hb): MRBC = -22.84loge EC + 65.83.This equation allowed calculation of MRBC based on EC which has practical applications such as the diagnosis of anemia.

Clinical presentation of delayed hemolytic transfusion reactions and hyperhemolysis in sickle cell disease

Red blood cell (RBC) transfusion therapy is a key component in the comprehensive management of patients with sickle cell disease (SCD). Consequently, most adult SCD patients will receive at least one, and many will receive more than a hundred RBC transfusions in their lifetime. SCD patients develop RBC alloantibodies much more frequently than non-SCD transfused patients, which often make the selection of compatible RBCs extremely difficult, in addition to placing patients at significantly higher risk of suffering from delayed hemolytic transfusion reactions (DHTRs). Similar to alloimunization, DHTRs are much more common in patients with SCD compared to other heavily transfused populations, and are particularly consequential due to their propensity to cause hyperhemolysis, a life-threatening phenomenon in which both transfused RBCs in addition to the patient's own sickle-erythrocytes are destroyed. In this review, we highlight the incidence and pathophysiology of DHTRs; illustrate common presentations, appropriate evaluations and outcomes of DHTRs in patients with SCD; and discuss strategies for preventing or reducing the likelihood of DHTRs from occurring.

Hemolytic Anemia: Evaluation and Differential Diagnosis

Hemolytic anemia is defined by the premature destruction of red blood cells, and can be chronic or life-threatening. It should be part of the differential diagnosis for any normocytic or macrocytic anemia. Hemolysis may occur intravascularly, extravascularly in the reticuloendothelial system, or both. Mechanisms include poor deformability leading to trapping and phagocytosis, antibody-mediated destruction through phagocytosis or direct complement activation, fragmentation due to microthrombi or direct mechanical trauma, oxidation, or direct cellular destruction. Patients with hemolysis may present with acute anemia, jaundice, hematuria, dyspnea, fatigue, tachycardia, and possibly hypotension. Laboratory test results that confirm hemolysis include reticulocytosis, as well as increased lactate dehydrogenase, increased unconjugated bilirubin, and decreased haptoglobin levels. The direct antiglobulin test further differentiates immune causes from nonimmune causes. A peripheral blood smear should be performed when hemolysis is present to identify abnormal red blood cell morphologies. Hemolytic diseases are classified into hemoglobinopathies, membranopathies, enzymopathies, immune-mediated anemias, and extrinsic nonimmune causes. Extrinsic nonimmune causes include the thrombotic microangiopathies, direct trauma, infections, systemic diseases, and oxidative insults. Medications can cause hemolytic anemia through several mechanisms. A rapid onset of anemia or significant hyperbilirubinemia in the neonatal period should prompt consideration of a hemolytic anemia.

Unusual Anemias

Many processes lead to anemia. This review covers anemias that are less commonly encountered in the United States. These anemias include hemoglobin defects like thalassemia, bone marrow failure syndromes like aplastic anemia and pure red cell aplasia, and hemolytic processes such as paroxysmal nocturnal hemoglobinuria. The pathogenesis, diagnostic workup, and treatment of these rare anemias are reviewed.

Hematologic manifestations of babesiosis

BACKGROUND

Babesiosis, a zoonotic parasitic infection transmitted by the Ixodes tick, has become an emerging health problem in humans that is attracting attention worldwide. Most cases of human babesiosis are reported in the United States and Europe. The disease is caused by the protozoa of the genus Babesia, which invade human erythrocytes and lyse them causing a febrile hemolytic anemia. The infection is usually asymptomatic or self-limited in the immunocompetent host, or follows a persistent, relapsing, and/or life threatening course with multi-organ failure, mainly in the splenectomized or immunosuppressed patients. Hematologic manifestations of the disease are common. They can range from mild anemia, to severe pancytopenia, splenic rupture, disseminated intravascular coagulopathy (DIC), or even hemophagocytic lymphohistiocytosis (HLH).

CASE PRESENTATION

A 70 year old immunocompetent female patient living in New York City presented with a persistent fever, night sweats, and fatigue of 5 days duration. Full evaluation showed a febrile hemolytic anemia along with neutropenia and thrombocytopenia. Blood smear revealed intraerythrocytic Babesia, which was confirmed by PCR. Bone marrow biopsy was remarkable for dyserythropoiesis, suggesting possible HLH, supported by other blood workup meeting HLH-2004 trial criteria.

CONCLUSION

Human babesiosis is an increasing healthcare problem in the United States that is being diagnosed more often nowadays. We presented a case of HLH triggered by Babesia microti that was treated successfully. Also, we presented the hematologic manifestations of this disease along with their pathophysiologies.

Variable Clinical Presentations of ABO Incompatibility in Dizygotic Twins

Newborns with ABO blood group incompatibility can have a spectrum of clinical presentations from remaining asymptomatic to severe hemolytic anemia with jaundice. This case presentation discusses dizygotic twins who demonstrated both ends of the clinical spectrum. Similar cases in which there is such extreme variation between twins were not attainable in the current literature, which prompted the authors to present it as a rare occurrence and one that was unexpected based on their past experience with ABO incompatibility both in singletons and in twins.

Impairment of bone health in pediatric patients with hemolytic anemia

Introduction

Sickle cell anemia and thalassemia result in impaired bone health in both adults and youths. Children with other types of chronic hemolytic anemia may also display impaired bone health.

Study Design

To assess bone health in pediatric patients with chronic hemolytic anemia, a cross-sectional study was conducted involving 45 patients with different forms of hemolytic anemia (i.e., 17 homozygous sickle cell disease and 14 hereditary spherocytosis patients). Biochemical, radiographic and anamnestic parameters of bone health were assessed.

Results

Vitamin D deficiency with 25 OH-vitamin D serum levels below 20 ng/ml was a common finding (80.5%) in this cohort. Bone pain was present in 31% of patients. Analysis of RANKL, osteoprotegerin (OPG) and osteocalcin levels indicated an alteration in bone modeling with significantly elevated RANKL/OPG ratios (control: 0.08+0.07; patients: 0.26+0.2, P = 0.0007). Osteocalcin levels were found to be lower in patients compared with healthy controls (68.5+39.0 ng/ml vs. 118.0+36.6 ng/ml, P = 0.0001). Multiple stepwise regression analysis revealed a significant (P<0.025) influence of LDH (partial r² = 0.29), diagnosis of hemolytic anemia (partial r² = 0.05) and age (partial r² = 0.03) on osteocalcin levels. Patients with homozygous sickle cell anemia were more frequently and more severely affected by impaired bone health than patients with hereditary spherocytosis.

Conclusion

Bone health is impaired in pediatric patients with hemolytic anemia. In addition to endocrine alterations, an imbalance in the RANKL/OPG system and low levels of osteocalcin may contribute to this impairment.

[Tropical malaria in children in the Republic of Tajikistan]

The complications of tropical malaria were noted in 25 (9.4%) of 196 pediatric patients followed up. These included cerebral malaria in 8 (3%), severe hemolytic anemia in 15 (5.7%), hemoglobinuric fever in 1 (0.37%), and malarial hepatitis in 1 (0.37%). The occurrence of complications was associated with the late referral of patients to a health care facility and untimely treatment, as well as with preliminary misdiagnoses (acute respiratory viral infection, typhoid-parathyphoid fever, meningitis, acute enteric infection, viral hepatitis, sepsis). The main reasons for late diagnosis were the absence of malarial paroxysm at the onset of disease in infants and the wrong type of a temperature curve.

[Hemolytic anemia secondary to the placement of a portosystemic stented shunt]

INTRODUCTION

portal hypertension and variceal hemorrhage are common complications of hepatic cirrhosis, both associated with a high morbimortality. Portal system decompression by the placement of a transjugular intrahepatic portosystemic stented shunt, can reduce portal venus pressure and is effective controling complications of portal hypertension, like variceal hemorrhage and ascitis. The aim of this document is to describe a case of hemolytic anemia secondary to the placement of a transjugular intrahepatic portosystemic stented shunt.

CLINICAL CASE

patient with portal hypertension secondary to liver cirrosis was given a transjugular intrahepatic portosystemic stented shunt for recurrent variceal hemorrhage. After the procedure, hemoglobin decreased 2 g/dL, associated with reticulocitosis, hipohaptoglobinemia, elevated lactic dehydrogenase and indirect hyperbilirrubinemia with negative Coombs test. The peripheral blood smear showed abnormal erythrocytes, with the prevalence of schistocytes. The final diagnosis was hemolytic anemia secondary to transjugular intrahepatic portosystemic stented shunt.

CONCLUSIONS

the hemolytic anemia secondary to Transjugular Intrahepatic Portosystemic Stented Shunt is a rare complication. Usually, it has a benign prognosis, and it is self-limited once the stent is endothelialized.

Cardiac remodelling, blood chemistry, haematology and oxygen consumption of Atlantic cod, Gadus morhua L., induced by experimental haemolytic anaemia with phenylhydrazine

Anaemia is a common pathology associated with many infectious and non-infectious diseases. The effects of haemolytic anaemia induced by i.p. injection of phenylhydrazine (PHZ) were studied in Atlantic cod. Phenylhydrazine injection (0.3 mg kg(-1)) in a DMSO and saline vehicle induced a reproducible and stable anaemia reducing haematocrit, (Hct) by 62% over 3 weeks. Controls consisted of fish injected with saline and DMSO/saline vehicle with minimal effects on Hct or whole blood haemoglobin (Hb). Although anaemia resulted in reduced blood lactate and glucose in PHZ injected fish, there were no effects of anaemia on blood, sodium, chloride or potassium. Similarly, there were no changes in the relative proportions of leucocytes in the blood although an increase in the number of immature erythrocytes was observed in the anaemic fish. Anaemic fish showed a 29 and 22% increase in cardiac somatic index (CSI) relative to saline and vehicle controls, respectively, although there were no significant differences in the linear dimensions of the ventricle. Changes in cardiac somatic and ventricular somatic index correlated positively and significantly with Hct but not with whole blood Hb concentration. Anaemic fish had significantly reduced resting routine oxygen consumption compared with vehicle controls but were not able to increase oxygen consumption following a bout of exhaustive exercise. Plasma lactate concentrations increased significantly after exercise to a greater extent in anaemic fish compared with vehicle control fish. Phenylhydrazine is a useful model for studying haemolytic anaemia in Atlantic cod with minimal effects on blood biochemistry and haematology and clearly reduces the aerobic capacity in Atlantic cod.

A closer look at paroxysmal nocturnal hemoglobinuria

Knowledge of the molecular mechanisms leading to the paroxysmal nocturnal hemoglobinuria (PNH) phenotypes has substantially increased in the past two decades. The associated intravascular hemolysis, hypercoagulablilty, and bone marrow failure result in a wide range of clinical sequlae. Although treatment has usually been symptomatic through several modalities and rarely curative through hematopoietic cell transplantation, recent development of the novel targeted therapeutic agent eculizumab has offered new promises for this highly morbid and fatal disease. This review summarizes current knowledge of the pathophysiology, diagnostic modalities, clinical implications, and treatment approaches of patients with PNH.

Anti-Kpa-induced severe delayed hemolytic transfusion reaction

Kpa is a low-frequency antigen occurring in less than 2 percent of the Caucasian population. Mild to moderate delayed hemolytic transfusion reactions (DHTR) and hemolytic disease of the fetus and newborn attributable to anti-Kpa have been reported. Severe overt DHTR has not been reported with anti-Kpa. A case of a severe DHTR attributed to anti-Kpa after multiple RBC transfusions is being reported. A 52-year-old Caucasian woman received multiple units of RBCs for a lower gastrointestinal bleed. She was referred to our institution for hepatic and renal failure, which was supported by laboratory findings of peak LDH, bilirubin, BUN, and creatinine elevations. Hemoglobin had dropped on Day 10 after transfusion. The DAT and antibody screen (ABS) were negative. Initial workup and subsequent ABS were negative. Anti-Kpa was identified when an additional RBC panel was tested. One of the RBC units transfused was incompatible by antihuman globulin (AHG) crossmatch with the patient's plasma and typed positive for Kpa. DHTR was confirmed after extensive workup. The patient responded to supportive therapy and experienced an uneventful recovery. DHTR may not be considered when DAT and ABS are negative. However, correlation of recent transfusion with signs and symptoms should alert the clinician to entertain and investigate a DHTR that should include the AHG crossmatch of all implicated RBC units. The severity of the reaction also raises concerns as to when and what antigen specificity should be considered for inclusion in the antibody screening cells.

Heme induces endothelial tissue factor expression: potential role in hemostatic activation in patients with hemolytic anemia

OBJECTIVES

We explored the possibility that heme, an inflammatory mediator and a product of intravascular hemolysis in patients with hemolytic anemia including sickle cell disease, could modulate hemostasis by an effect on endothelial tissue factor (TF) expression.

METHODS

Levels of TF mRNA, protein and procoagulant activity were measured in heme-treated endothelial cells.

RESULTS

Heme induces TF expression on the surface of both macrovascular and microvascular endothelial cells in a concentration-dependent manner, with 12-fold to 50-fold induction being noted (enzyme-linked immunosorbent assay) between 1 and 100 microm heme (P < 0.05). Complementary flow cytometry studies showed that the heme-mediated endothelial TF expression was quantitatively similar to that of tumor necrosis factor-alpha (TNF-alpha). Heme also upregulated the expression of TF mRNA (8-fold to 26-fold), protein (20-fold to 39-fold) and procoagulant activity (5-fold to 13-fold) in endothelial cells in a time-dependent manner. The time-course of heme-mediated TF antigen expression paralleled the induction of procoagulant activity, with antibody blocking studies demonstrating specificity for TF protein. Interleukin (IL)-1alpha, and TNF-alpha are not involved in mediating the heme effect, as antibodies against these cytokines and IL-1-receptor antagonist failed to block heme-induced TF expression. Inhibition of heme-induced TF mRNA expression by sulfasalazine and curcumin suggested that the transcription factor nuclear factor kappaB is involved in mediating heme-induced TF expression in endothelial cells.

CONCLUSIONS

Our results demonstrate that heme induces TF expression by directly activating endothelial cells, and that heme-induced endothelial TF expression may provide a pathophysiologic link between the intravascular hemolytic milieu and the hemostatic perturbations previously noted in patients with hemolytic anemia including sickle cell disease.

[Thrombotic microangiopathies]

Thrombotic microangiopathies are disorders of microvascular occlusion and are characterized by thrombocytopenia and microangiopathic haemolytic anaemia. Varying additional signs and symptoms of organ ischaemia may be present. Thrombotic microangiopathies are pathophysiologically heterogenous disorders and include primarily thrombotic thrombocytopenic purpura and haemolytic uraemic syndrome. Besides this, they may occur in association with certain diseases or drugs, or after allogeneic haematopoietic stem cell transplantation.

Haemolytic anaemia as a first sign of Wilson's disease

A 19-year-old female presented with haemolytic anaemia and subsequently developed liver failure. This raised suspicion of Wilson's disease, which was confirmed by Kayser-Fleischer rings, a low ceruloplasmin level, raised 24-hour urinary copper excretion and two mutations in the 'Wilson gene'. She was successfully treated with D-penicillamine and zinc. In young patients with unexplained haemolysis, liver dysfunction or neuro-psychiatric symptoms, Wilson's disease should be considered.

Hemolytic anemia presenting with idiopathic intracranial hypertension

We report on an 8-year-old girl with hemolytic anemia because of infection with parvovirus B19 and increased intracranial pressure. She presented acutely with headache, vomiting, and mild scleral and mucosal icterus. Upon evaluation, the patient exhibited profound hemolytic anemia, papilledema, and increased intracranial pressure. The patient was treated with intravenous immunoglobulin, prednisone, and packed red blood cells. Concurrent with an improvement of her anemia, she experienced a gradual resolution of her headache, vomiting, and optic-disc swelling. Signs of idiopathic intracranial hypertension may occur as a consequence of severe anemia, and are reversible upon correction of the underlying hematologic disorder.

Thrombotic Thrombocytopenic Purpura in Humans and Mice

Thrombotic thrombocytopenic purpura (TTP) is a disorder of blood coagulation that presents classically with the pentad of fever, thrombocytopenia, microangiopathic hemolytic anemia, renal dysfunction and mental status changes. However, the clinical presentation can be quite variable making the diagnosis difficult in many cases. “Hyaline” microthrombi composed primarily of platelets and Von Willebrand Factor (VWF) are found in the small vessels of affected organs and represent the pathological hallmark of the disease. The accompanying tissue ischemia is thought to explain the clinical TTP signs and symptoms. Pathogenesis of TTP has been linked to dysfunction of ADAMTS13, a metalloprotease whose only known substrate is VWF. Interestingly, further investigation into the natural history of TTP has demonstrated that ADAMTS13 deficiency likely is necessary, but not sufficient for the development of this disease, suggesting that additional genetic and/or environmental factors are required for TTP pathogenesis. Recently, a mouse model of TTP was established that recapitulates many of the key clinical features of this disease, including the requirement for further genetic and environmental factors in addition to ADAMTS13 deficiency. Therefore, in addition to being useful for the direct study of disease pathophysiology in vivo , this mouse model may also play a key role in elucidating some of the important environmental and genetic contributors to disease pathogenesis. Here we will review TTP in humans, and then discuss recent information gained from the analysis of ADAMTS13-deficient mice.

Erythropoietin and iron-restricted erythropoiesis

Twenty five years ago, Finch summarized knowledge gained primarily from studies of normal individuals, patients with hereditary hemolytic anemias, and patients with hemochromatosis [1]. Under conditions of basal erythropoiesis in normal subjects, plasma iron turnover (as an index of marrow erythropoietic response) is little affected, whether transferrin saturation ranges from very low to very high levels. In contrast, the erythropoietic response in individuals with congenital hemolytic anemia, in whom erythropoiesis is chronically raised up to sixfold over basal levels [2], is affected (and limited) by serum iron levels and by transferrin saturation [3]. Patients with hemochromatosis who underwent serial phlebotomy were observed to mount erythropoietic responses of up to eightfold over basal rates, attributed to the maintenance of very high serum iron and transferrin saturation levels in these patients [4], whereas normal individuals were shown to have difficulty providing sufficient iron to support rates of erythropoiesis greater than three times basal rates [5]. These observations led Finch to identify a "relative iron deficiency" state, also known as "functional iron deficiency," which he defined as circumstances in which increased erythron iron requirements exceed the available supply of iron [6]. In another clinical setting, patients undergoing autologous blood donation represent a model for perisurgical blood loss and the erythropoietic response. Insights gained over the last 20 years regarding the relationship between erythropoietin, iron, and erythropoiesis, along with implications for clinical management, will be reviewed.

Enhanced suicidal death of erythrocytes from gene-targeted mice lacking the Cl-/HCO(3)(-) exchanger AE1

Genetic defects of anion exchanger 1 (AE1) may lead to spherocytic erythrocyte morphology, severe hemolytic anemia, and/or cation leak. In normal erythrocytes, osmotic shock, Cl(-) removal, and energy depletion activate Ca(2+)-permeable cation channels with Ca(2+)-induced suicidal erythrocyte death, i.e., surface exposure of phosphatidylserine, cell shrinkage, and membrane blebbing, all features typical for apoptosis of nucleated cells. The present experiments explored whether AE1 deficiency favors suicidal erythrocyte death. Peripheral blood erythrocyte numbers were significantly smaller in gene-targeted mice lacking AE1 (AE1(-/-) mice) than in their wild-type littermates (AE1(+/+) mice) despite increased percentages of reticulocytes (AE1(-/-): 49%, AE1(+/+): 2%), an indicator of enhanced erythropoiesis. Annexin binding, reflecting phosphatidylserine exposure, was significantly larger in AE1(-/-)erythrocytes/reticulocytes ( approximately 10%) than in AE1(+/+) erythrocytes ( approximately 1%). Osmotic shock (addition of 400 mM sucrose), Cl(-) removal (replacement with gluconate), or energy depletion (removal of glucose) led to significantly stronger annexin binding in AE1(-/-) erythrocytes/reticulocytes than in AE1(+/+) erythrocytes. The increase of annexin binding following exposure to the Ca(2+) ionophore ionomycin (1 muM) was, however, similar in AE1(-/-) and in AE1(+/+) erythrocytes. Fluo3 fluorescence revealed markedly increased cytosolic Ca(2+) permeability in AE1(-/-) erythrocytes/reticulocytes. Clearance of carboxyfluorescein diacetate succinimidyl ester-labeled erythrocytes/reticulocytes from circulating blood was more rapid in AE1(-/-) mice than in AE1(+/+) mice and was accelerated by ionomycin treatment in both genotypes. In conclusion, lack of AE1 is associated with enhanced Ca(2+) entry and subsequent scrambling of cell membrane phospholipids.

Catastrophic antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a thrombotic disorder associated with autoantibodies that target membrane phospholipids and phospholipid-binding proteins, which regulate coagulation. APS is usually characterized by major arterial or venous occlusions, pregnancy complications, or both. In 1992, Asherson described an unusual variant of APS termed the catastrophic antiphospholipid syndrome (also known as Asherson's syndrome), the hallmark of which is rapid multiorgan failure caused by widespread small-vessel thrombi. Empiric treatments have improved the prognosis of patients, but half still die from thrombotic diathesis, even though those who survive the acute stages frequently remain well. Given the persistently high mortality rate, efforts have been underway to facilitate early diagnosis, institute effective treatments in a timely manner and to better understand the cause (or causes) of this extreme condition in order to improve outcomes.

Circulating Endothelial Cells as a Prognostic Marker in Thrombotic Microangiopathy

BACKGROUND

Circulating endothelial cells (CECs) are a reliable marker of disease activity in a variety of vascular disorders. Damage to microvascular endothelial cells is a hallmark of thrombotic microangiopathy (TMA). The aim of this study is to identify and count CECs during the course of TMA and evaluate whether cell numbers may serve as a prognostic marker in patients undergoing plasma exchange.

METHODS

Fifteen patients (8 women, 7 men) aged 31 to 66 years with TMA of different causes were studied before and after 4 sessions of plasma exchange. CECs were isolated by using anti-CD146-driven immunomagnetic isolation and counted after staining with Ulex Europaeus lectin-1.

RESULTS

Numbers of CECs were markedly elevated in all patients before treatment (64 to 672 CEC/mL; mean, 320 +/- 205 CEC/mL) compared with healthy controls (0 to 16 CEC/mL; mean, 6.4 +/- 4.2 CEC/mL; P < 0.001). Patients with a favorable outcome had significantly greater initial CEC levels (mean, 426 +/- 175 CEC/mL; P < 0.001), and cell numbers decreased significantly after 4 treatments of plasma exchange (mean, 101 +/- 53 CEC/mL; P = 0.001). Patients with disease unresponsive to plasma exchange presented with lower initial CEC levels (mean, 108 +/- 36 CEC/mL), and numbers failed to decrease after plasma exchange (mean, 114 +/- 57 CEC/mL; P = 0.827).

CONCLUSION

Markedly elevated numbers of CECs reflect severe and widespread endothelial damage in patients with TMA. Cell numbers at presentation and their degree of decrease after 4 sessions of plasma exchange could provide important prognostic clues.

[Physiopathological mechanisms of abomasal Trichostrongylidae infections in small ruminants]

Abomasal Trichostrongylidae infections are still today an important cause of scarce performances in small ruminants, mainly when bred in extensive systems. Although morpho-biology, symptomatology, prophylaxis and therapy of these infections are well known, other, such as physiopathology, are less investigated. The aim of the present note is to review the more important physiopathogenetic mechanisms of abomasal Trichostrongylidae infections, with special emphasis to Haemonchus spp. and Teladorsagia spp. The parasitic anorexia due to the action of gastrin, the defects of digestion due to hypocloridia, the scarce intestinal absorption and anaemia caused by H. contortus are discussed. Furthermore, the effects of hypersensitivity sometimes caused by these abomasal nematodes are examined. A better knowledge of physiopathological mechanisms can represent an important factor to understand the relationships between host and parasite, useful to set up new diagnostic techniques or new therapeutic and prophylactic protocols for sanitary education and control plans of these important and widespread parasitic infections.

Validation of a patient satisfaction questionnaire for anemia treatment, the PSQ-An

BACKGROUND

Treating anemia associated with chemotherapy and many cancers is often necessary. However, patient satisfaction with anemia treatment is limited by the lack of validated instruments. We developed and validated a new treatment-specific patient satisfaction instrument: the Patient Satisfaction Questionnaire for Anemia Treatment (PSQ-An). Treatment burden and overall satisfaction scales were designed for ease of use in clinical practice.

METHODS

312 cancer patients (141 breast, 69 gynecological, and 102 non-small cell lung) were targeted to complete the PSQ-An at 4 week intervals. Data from weeks 5 and 9 were analyzed. Patients also completed the MOS SF-36 Global Health assessment and questions concerning resources devoted to anemia treatment. Item reduction used endorsement rates, floor/ceiling effects, and item-item correlations. Factor analysis identified meaningful subscales. Test-retest reliability was assessed. Construct validity was tested, using Pearson's correlations, by comparing subscale scores to Global Health, hemoglobin levels, and resources devoted to anemia treatment.

RESULTS

The overall response rate was 92.9% (264/284) at week 5. Most (84.2%) of the patients were female, and the mean (SD) age was 60.2 (+/- 11.8) years. Two distinct subscales were identified measuring treatment burden (7 items) and overall satisfaction (2 items). Test-retest reliability was examined (ICC: 0.45-0.67); both were internally consistent (alpha = 0.83). Both subscales exhibited convergent and divergent validity with independent measures of health. ANOVA results indicated that the PSQ-An Satisfaction subscale discriminated between 5 levels of MOS SF-36 Global Health (P = 0.006).

CONCLUSION

The PSQ-An is a validated, treatment-specific instrument for measuring satisfaction with anemia treatment for cancer patients. PSQ-An subscales reflect the burden of injection anemia treatment on cancer patients and their assessment of the overall treatment value.

Hepcidin mRNA levels in mouse liver respond to inhibition of erythropoiesis

Hepcidin, a key regulator of iron metabolism, decreases intestinal absorption of iron and its release from macrophages. Iron, anemia, hypoxia, and inflammation were reported to influence hepcidin expression. To investigate regulation of the expression of hepcidin and other iron-related genes, we manipulated erythropoietic activity in mice. Erythropoiesis was inhibited by irradiation or posttransfusion polycythemia and stimulated by phenylhydrazine administration and erythropoietin. Gene expression of hepcidin and other iron-related genes (hemojuvelin, DMT1, ferroportin, transferrin receptors, ferritin) in the liver was measured by the real-time polymerase chain reaction. Hepcidin expression increased despite severe anemia when hematopoiesis was inhibited by irradiation. Suppression of erythropoiesis by posttransfusion polycythemia or irradiation also increased hepcidin mRNA levels. Compensated hemolysis induced by repeated phenylhydrazine administration did not change hepcidin expression. The decrease caused by exogenous erythropoeitin was blocked by postirradiation bone marrow suppression. The hemolysis and anemia decrease hepcidin expression only when erythropoiesis is functional; on the other hand, if erythropoiesis is blocked, even severe anemia does not lead to a decrease of hepcidin expression, which is indeed increased. We propose that hepcidin is exclusively sensitive to iron utilization for erythropoiesis and hepatocyte iron balance, and these changes are not sensed by other genes involved in the control of iron metabolism in the liver.

A surgical case for severe hemolytic anemia after mitral valve repair

We report a rare case of severe hemolytic anemia accompanied by moderate renal insufficiency after mitral valve repair. Although the degree of the residual mitral regurgitation was less than 1+ during the first three weeks after the operation, the maximum lactate dehydrogenase (LDH) was up to 7,430 U/l and the minimum hemoglobin was 4.9 g/dl. The mitral valve replacement successfully resolved the hemolysis, but the renal function did not completely recover.

Cardiopulmonary complications of sickle cell disease: role of nitric oxide and hemolytic anemia

Medical advances in the management of patients with sickle cell disease, thalassemia, and other hemolytic anemias have led to significant increases in life expectancy. Improved public health, neonatal screening, parental and patient education, advances in red cell transfusion medicine, iron chelation therapy, penicillin prophylaxis for children, pneumococcal immunization, and hydroxyurea therapy have all likely contributed to this effect on longevity. Importantly, as a generation of patients with sickle cell disease and thalassemia ages, new chronic complications of these hemoglobinopathies develop. In this context, pulmonary hypertension is emerging as one of the leading causes of morbidity and mortality in adult sickle cell and thalassemia patients, and likely in patients with other hemolytic anemias. A common feature of both sickle cell disease and thalassemia is intravascular hemolysis and chronic anemia. Recent data suggest that chronic intravascular hemolysis is associated with a state of endothelial dysfunction characterized by reduced nitric oxide (NO) bioavailability, pro-oxidant and pro-inflammatory stress and coagulopathy, leading to vasomotor instability and ultimately producing a proliferative vasculopathy, a hallmark of which is the development of pulmonary hypertension in adulthood. In conclusion, pulmonary hypertension is common in patients with hereditary hemolytic anemias and is associated with a high risk of death in patients with sickle cell disease. New therapies targeting this vasculopathy and aimed at normalizing the vasodilator:vasoconstrictor balance are discussed.

The Clinical Spectrum of Thrombotic Thrombocytopenic Purpura

The clinical syndrome of fever, neurologic abnormalities, renal impairment with laboratory findings of thrombocytopenic and microangiopathic hemolytic anemia is seen in thrombotic thrombocytopenic purpura (TTP) and a variety of disorders associated with thrombotic microangiopathy (TMA). With improved understanding of the pathogenesis of the perturbed metabolic pathway of von Willebrand factor in TTP, the classic Moschcowitz syndrome, now more accurately referred to as idiopathic TTP, can be distinguished from other TMAs. The distinguishing features are useful not only in providing an accurate diagnosis but also help to determine the best therapeutic strategy.

CD46: expanding beyond complement regulation

During the 1980s CD46 was discovered in a search for C3b binding proteins of human peripheral blood cells. Its role as an inactivator of C3b and C4b deposited on self-tissue is highlighted by the observation that partial deficiency of CD46 is a predisposing factor to hemolytic uremic syndrome. This discovery has an impact on the treatment options for these patients. Other new findings have expanded the role of CD46 in immunity and disease. For example, signaling through CD46 on human T lymphocytes drives them to become regulatory cells, indicating a novel link between the complement system and cellular immunity. Also, CD46 interacts with at least seven human pathogens and participates in reproduction/fertilization, further suggesting that dissecting its multi-faceted activities will have important clinical implications.

Hemolytic anemia

Hemolysis presents as acute or chronic anemia, reticulocytosis, or jaundice. The diagnosis is established by reticulocytosis, increased unconjugated bilirubin and lactate dehydrogenase, decreased haptoglobin, and peripheral blood smear findings. Premature destruction of erythrocytes occurs intravascularly or extravascularly. The etiologies of hemolysis often are categorized as acquired or hereditary. Common acquired causes of hemolytic anemia are autoimmunity, microangiopathy, and infection. Immune-mediated hemolysis, caused by antierythrocyte antibodies, can be secondary to malignancies, autoimmune disorders, drugs, and transfusion reactions. Microangiopathic hemolytic anemia occurs when the red cell membrane is damaged in circulation, leading to intravascular hemolysis and the appearance of schistocytes. Infectious agents such as malaria and babesiosis invade red blood cells. Disorders of red blood cell enzymes, membranes, and hemoglobin cause hereditary hemolytic anemias. Glucose-6-phosphate dehydrogenase deficiency leads to hemolysis in the presence of oxidative stress. Hereditary spherocytosis is characterized by spherocytes, a family history, and a negative direct antiglobulin test. Sickle cell anemia and thalassemia are hemoglobinopathies characterized by chronic hemolysis.

Deletion of alpha4 integrins from adult hematopoietic cells reveals roles in homeostasis, regeneration, and homing

We have explored the functional implications of inducible alpha4 integrin deletion during adult hematopoiesis by generating a conditional-knockout mouse model, and we show that alpha4 integrin-deficient hematopoietic progenitor cells accumulate in the peripheral blood soon after interferon-induced gene deletion. Although their numbers gradually stabilize at a lower level, progenitor cell influx into the circulation continues at above-normal levels for more than 50 weeks. Concomitantly, a progressive accumulation of progenitors occurs within the spleen. In addition, the regeneration of erythroid and myeloid progenitor cells is delayed during stress hematopoiesis induced by phenylhydrazine or by 5-fluorouracil, suggesting impairment in early progenitor expansion in the absence of alpha4 integrin. Moreover, in transplantation studies, homing of alpha4(-/-) cells to the bone marrow, but not to the spleen, is selectively impaired, and short-term engraftment is critically delayed in the early weeks after transplantation. Thus, conditional deletion of alpha4 integrin in adult mice is accompanied by a novel hematopoietic phenotype during both homeostasis and recovery from stress, a phenotype that is distinct from the ones previously described in alpha4 integrin-null chimeras and beta1 integrin-conditional knockouts.

[Hemolysis following valve surgery]

Hemolysis is a frequent complication of the implant of prosthetic valves, and is conditioned by a variety of factors, most of which related to the type of valve implanted and to the hemodynamic conditions following implantation. If sufficiently severe, it may lead to varying degrees of hemolytic anemia. The following laboratory tests are useful to diagnose and assess the severity of hemolytic anemia: hemoglobin levels; reticulocyte count; the demonstration of schistocytes on a blood smear; serum levels of lactic dehydrogenase, haptoglobin and iron. Treatment of hemolysis includes the supplementation of iron and folate when their deficiency is evident. Transfusions are necessary only in cases of severe anemia refractory to treatment. The use of beta-blockers appears to decrease the severity of hemolysis, likely because of the induction of bradycardia and of their negative inotropic effects. Some cases have been described of erythropoietin treatment for hemolytic anemia in these conditions, with favorable outcome. However erythropoietin use should currently be restricted to patients with severe hemolytic anemia in whom surgical repair or transfusions should be avoided or deferred. The recognition and the estimation of severity of hemolysis after valve implantation are important steps in the patients' follow-up and the premise for a rational treatment.

Reduction of hemolysis without reoperation following mitral valve repair

Hemolytic anemia following mitral valve repair and annular ring placement is uncommon compared with mitral valve replacement. A 60-year-old man, who had undergone mitral valve repair with a Duran ring, developed hemolytic anemia and needed a blood transfusion. Transesophageal echocardiography revealed a paravalvular mitral regurgitation jet colliding with the Duran ring. Most cases of severe hemolysis after mitral valve repair have undergone reoperation, but in the present case study, the hemolysis after mitral valve repair reduced without the need for reoperation, although the paravalvular mitral regurgitation jet continued to collide with the Duran ring.

Cyclophosphamide exerts no beneficial effect over prednisone alone in the initial treatment of acute immune-mediated hemolytic anemia in dogs: a randomized controlled clinical trial

Cyclophosphamide is commonly used with prednisone in the initial treatment of severe idiopathic immune-mediated hemolytic anemia (IMHA) in dogs because retrospective reports suggest its benefit. This randomized controlled prospective clinicaltrial evaluated whether combined cyclophosphamide and prednisone therapy is more efficacious than prednisone therapy alone in the initial treatment of IMHA. Eighteen dogs with acute, severe idiopathic IMHA were randomly assigned to 1 of 2 treatment groups. The P group received prednisone therapy alone (1-2 mg/kg PO q12h), and the PC group received prednisone (1-2 mg/kg PO q12h) and cyclophosphamide (50 mg/m2 PO q24h for 4 consecutive days a week) for 4 weeks. The mortality rate in the P group was 20% (2 of 10), and in the PC group, the mortality rate was 38% (3 of 8). There was no difference in sequential CBC evaluations between the 2 groups. However, whereas dogs in the P group showed increases in reticulocyte count, reticulocytosis was suppressed in dogs in the PC group during the 1st week of therapy. Spherocytosis resolved more quickly in the P group (day 21) than in the PC group (day 28), but the time taken to achieve a negative Coombs' test result was comparable between groups. No difference was observed in the volume of packed red blood cells (pRBCs) given per transfusion between treatment groups, but more dogs in the PC group required a 2nd transfusion. The results of this limited study suggest that cyclophosphamide plus prednisone has no benefit over prednisone alone in the initial treatment of acute, severe idiopathic IMHA indogs.

CAMPATH-1H in the treatment of autoimmune cytopenias

BACKGROUND

The autoimmune cytopenias encompass the disorders of immune thrombocytopenia purpura (ITP), pure red-cell aplasia (PRCA), autoimmune hemolytic anemia (AIHA), autoimmune neutropenia and various combinations of these conditions. T lymphocytes are thought to play an important role in the pathogenesis of autoimmune cytopenias, and the presence of autoantibody may represent an epiphenomenon, rather than the primary pathogenetic mechanism. The majority of patients usually respond to standard immunosuppressive therapy and can mostly be treated as out-patients. A small proportion, however, have severe, resistant and life-threatening disease, or may experience major morbidity from side effects of drugs given to treat their disease.

METHODS

We have treated 21 patients with autoimmune cytopenias with the MAb Campath-1H, and for later patients in this series, in combination with low dose CYA.

RESULTS

Responses were seen in 14 of 20 evaluable patients, although relapse occurred in seven patients. In many patients corticosteroid therapy could be discontinued or greatly reduced.

DISCUSSION

We conclude that Campath-1H can induce remissions in autoimmune cytopenias and we critically review its role in the treatment of these disorders.

Hemostatic complications in bone marrow transplantation: a retrospective analysis of 447 patients

BACKGROUND

Hemostatic complications are not uncommon after bone marrow transplantation (BMT). However, little is known about the frequency, localization, determinants, and outcome of hemostatic events in autologous and allogeneic BMT.

METHODS

Four hundred forty-seven patients (364 allogeneic, 83 autologous transplants) were evaluated retrospectively for the presence of hemostatic complications (bleeding, thrombosis, hepatic veno-occlusive disease [VOD], microangiopathic hemolytic anemia) from the start of conditioning therapy until June 2000.

RESULTS

A total of 83.2% of the patients presented with at least one hemostatic complication during the investigational period. Most bleeding episodes occurred within the first 4 weeks after transplantation and were relatively mild. However, 27.1% of the patients hemorrhaged severely, generally doubling the overall mortality of the BMT recipients. Fatal gastrointestinal or intracerebral hemorrhages contributed to 1.1% of the events. Bleeding was strongly associated with prolonged thrombocytopenia and graft-versus-host disease (GVHD). Hemorrhagic cystitis may additionally have been triggered by the preceding conditioning regimens containing cyclophosphamide. Thromboembolic events occurred most frequently in allogeneic transplant recipients, for whom the incidence was 14.6%. Chronic GVHD and treatment with steroids were the major determining factors. The incidence of hepatic VOD in 4.7% of the allogeneic transplant recipients was associated with a high fatality rate. Busulfan conditioning increased the VOD risk 2.6-fold. Moderate or severe microangiopathic hemolytic anemia was associated with GVHD and occurred in 14.6% of the allogeneic transplant recipients, leading to an increased overall mortality.

CONCLUSION

Hemostatic disturbances, commonly found in the course of transplantation, are associated with a high transplantation risk and closely related to thrombocytopenia and immunologic complications.

Primaquine-induced hemolytic anemia: effect of 6-methoxy-8-hydroxylaminoquinoline on rat erythrocyte sulfhydryl status, membrane lipids, cytoskeletal proteins, and morphology

Previous studies have shown that 6-methoxy-8-hydroxylaminoquinoline (MAQ-NOH), an N-hydroxy metabolite of the antimalarial drug, primaquine, is a direct-acting hemolytic agent in rats. To investigate the mechanism underlying this hemolytic activity, the effects of hemotoxic concentrations of MAQ-NOH on rat erythrocyte sulfhydryl status, membrane lipids, skeletal proteins, and morphology have been examined. Treatment of rat erythrocytes with a TC(50) concentration of MAQ-NOH (350 microM) caused only a modest and transient depletion of reduced glutathione (GSH) (~30%), which was matched by modest increases in the levels of glutathione disulfide and glutathione-protein mixed disulfides. Lipid peroxidation, as measured by thiobarbituric acid-reactive substances and F(2)-isoprostane formation, was induced in a concentration-dependent manner by MAQ-NOH. However, the formation of disulfide-linked hemoglobin adducts on membrane skeletal proteins and changes in erythrocyte morphology were not observed. These data suggest that hemolytic activity results from peroxidative damage to the lipid of the red cell membrane and is not dependent on skeletal protein thiol oxidation. However, when red cell GSH was depleted (>90%) by titration with diethyl maleate, hemolytic activity of MAQ-NOH was markedly enhanced. Of interest, exacerbation of hemotoxicity was not matched by increases in lipid peroxidation, but by the appearance of hemoglobin-skeletal protein adducts. Collectively, the data are consistent with the concept that MAQ-NOH may operate by more than one mechanism; one that involves lipid peroxidation in the presence of normal amounts of erythrocytic GSH, and one that involves protein oxidation in red cells with low levels of GSH, such as are seen in individuals with glucose-6-phosphate dehydrogenase deficiency.

A hypothesis of haemolysis in haemolytic anaemias associated with enzymopathies

A feature of a previously proposed mechanism of erythrocyte shape control is a control of the shape by the Donnan equilibrium ratio. An enzymopathy of the glycolytic pathway and nucleotide metabolism could alter the Donnan ratio, since it alters levels of phosphate intermediates and of end-products carbonic gas (CO(2)) and ammonia gas (NH(3)) which are ionized at the erythrocyte pH. Thus, a hypothesis of haemolysis in haemolytic anaemias associated with enzymopathies of the glycolytic pathway and nucleotide metabolism would be that it results from an inhibition of the mechanism by a modification of the Donnan ratio. This hypothesis seems plausible as it would explain coherently observations in these haemolytic anaemias.