Suppression of haematopoiesis by IgG autoantibodies from patients with systemic lupus erythematosus (SLE)

Pancytopenia with aplastic anemia in systemic lupus erythematosus: case series and literature review

Aplastic anemia (AA) is a rare, potentially catastrophic hematopoiesis failure manifested by pancytopenia and bone marrow aplasia. AA occurrence in Systemic Lupus Erythematosus (SLE) patients is extremely rare. The diagnosis may be delayed due to other possible pancytopenia etiologies. Confirmation of peripheral cytopenias diagnosis necessitates a bone marrow aspiration. The management of AA is challenging, and the literature reported using glucocorticoids, danazol, plasmapheresis, cyclophosphamide, intravenous immunoglobulin, and cyclosporine. We report two cases of SLE patients who presented with pancytopenia, with bone marrow biopsy confirmed AA. One case was treated with cyclophosphamide but unfortunately succumbed to Acute Respiratory Distress Syndrome (ARDS), while the other case was managed with rituximab with a good response. Interestingly, both patients were on azathioprine before the diagnosis of AA. A comprehensive search for reported cases of AA in PubMed, Scopus, and the Directory of Open Access Journals databases was performed to enhance the understanding of the diagnostic and management challenges associated with AA in SLE, facilitating ongoing exploration and research in this field. The decision to do a BM aspiration and biopsy is recommended for SLE patients with an abrupt decline in blood counts and previously stable blood counts.

Spontaneous regression of tumours. Possible cross reactivity of autoantibodies against carbonic anhydrase I

Spontaneous tumour regression in patients after high dose therapy and autologous stem cell transplantation or patients with standard therapy is accompanied with the presence of high titers autoantibodies against carbonic anhydrase I (CA I). The concomitant presence of aplastic anaemia-like syndrome in these patients points to parallel bone marrow suppression during this period. It seems that CA I, an 'obscure' enzyme, does not have any significant physiological role in humans. One possible explanation points to the fact that autoantibodies against CA I may target another antigen(s) which is(are) important in tumour growth as well as in normal haematopoiesis. One of the candidates for such a target is the DNA polymerase theta.

Human TLR8 induces inflammatory bone marrow erythromyeloblastic islands and anemia in SLE-prone mice

Anemia commonly occurs in systemic lupus erythematosus, a disease characterized by innate immune activation by nucleic acids. Overactivation of cytoplasmic sensors by self-DNA or RNA can cause erythroid cell death, while sparing other hematopoietic cell lineages. Whereas chronic inflammation is involved in this mechanism, less is known about the impact of systemic lupus erythematosus on the BM erythropoietic niche. We discovered that expression of the endosomal ssRNA sensor human TLR8 induces fatal anemia in Sle1.Yaa lupus mice. We observed that anemia was associated with a decrease in erythromyeloblastic islands and a block in differentiation at the CFU-E to proerythroblast transition in the BM. Single-cell RNAseq analyses of isolated BM erythromyeloblastic islands from human TLR8-expressing mice revealed that genes associated with essential central macrophage functions including adhesion and provision of nutrients were down-regulated. Although compensatory stress erythropoiesis occurred in the spleen, red blood cell half-life decreased because of hemophagocytosis. These data implicate the endosomal RNA sensor TLR8 as an additional innate receptor whose overactivation causes acquired failure of erythropoiesis via myeloid cell dysregulation.

A Practical Perspective of the Hematologic Manifestations of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic inflammatory disease with an unknown etiology that can affect any organ or system of the human body. Hematological, renal, or central nervous system manifestations in these patients result in great morbidity because high doses of glucocorticoids, cytotoxic medications, or biological drugs are required to control these manifestations. It is noteworthy that hematological involvement predominates during the first years of the disease and tends to last over time, with the premise that it may be the initial manifestation of the disease. Clear examples of this are the cases of hemolytic anemia and immune thrombocytopenia that can be initially classified as idiopathic or primary to be later classified as secondary when associated with infections, medications, neoplasms, or autoimmune diseases. The spectrum of hematologic manifestations in SLE is very broad, including lymphopenia, anemia, thrombocytopenia, or pancytopenia. In some cases, lymphadenopathy and splenomegaly are also identified. The vast majority of these manifestations denote high disease activity. However, many of these alterations have a multifactorial cause that must be taken into account to adopt a more complete therapeutic approach. The objective of this review is to characterize in detail the hematological manifestations of SLE to offer clinicians a practical vision of its diagnosis and treatment.

Immune-mediated Coombs negative intravascular haemolysis in systemic lupus erythematosus (SLE)

A 27-year-old woman presented with a history of excessive hair loss, loss of appetite, loss of weight, amenorrhoea and loss of axillary and pubic hair for 6 months followed by fever and vomiting for 5 months and abdominal pain for 1 month. During the course of her illness, the patient developed intravascular haemolysis as evidenced by a drop in haemoglobin, indirect hyperbilirubinaemia, raised lactate dehydrogenase (LDH) and haemoglobinuria. Examination revealed severe pallor, mild icterus, elevated jugular venous pressure, generalised lymphadenopathy and hyperpigmentation. Investigations revealed severe anaemia, indirect hyperbilirubinaemia, raised LDH and negative Coombs test. Antinuclear antibody and anti-dsDNA, anti-Sm and anti-SS-A/Ro antibodies were positive and complement C3 was low. The patient was diagnosed to have systemic lupus erythematosus and immune-mediated intravascular haemolysis and was treated with prednisolone and hydroxychloroquine. Haemolysis resolved following steroid therapy, and during follow-up, there were no further episodes of haemolysis.

Altered frequency of peripheral B-cell subsets and their correlation with disease activity in patients with systemic lupus erythematosus: A comprehensive analysis

Alternations of peripheral B-cell subsets are closely related to disease activity in systemic lupus erythematosus (SLE) and may also predict the relapse of SLE. In this study, we aimed to comprehensively analyse the frequency of peripheral B-cell subsets, and their correlation with disease activity in patients with SLE. The results showed that for B-cell subsets in the antigen-independent differentiation stage, the frequency of the peripheral hematopoietic stem cell (HSC) subset in all patients with SLE was significantly higher than that of control patients. Surprisingly, several significant correlations were noted in newly diagnosed patients with SLE including a positive correlation in the frequency of the common lymphoid progenitor cell (CLP) with cholesterol serum levels. For B-cell subsets in the antigen-dependent differentiation stage, the frequency of naïve B-cell (N-B) subsets in all patients with SLE was significantly higher than that in the control patients. Moreover, the frequency of plasmablasts positively correlated with the SLEDAI score in the newly diagnosed patients. For memory B-cell (M-B) subtypes in the antigen-dependent differentiation stage, the frequency of the class-switched memory B-cell (CSM-B) subsets was positively correlated with the serum levels of complement C3. Notably, the frequency of the CSM-B subset also negatively correlated with the SLEDAI score, whereas the non-class-switched memory B-cell (NSM-B) subset was positively correlated with the serum levels of haemoglobin. Collectively, these findings may contribute to a better understanding of the role played by different B-cell subsets in the pathogenesis of SLE.

Lower In-Hospital Mortality with Plasma Exchange than Plasmapheresis in a Subgroup Analysis of 374 Lupus Patients

Background

Apheresis treatment includes plasmapheresis (PP) and plasma exchange (PE), and these terms are commonly used interchangeably. Nevertheless, the two procedures are carried out differently. The aims of this study were to investigate the mortality rate of patients who underwent therapeutic apheresis and compare the mortality rate between PP and PE.

Methods

We conducted a medical chart review retrospective study. All identified subjects (n = 436) were over 20 years old with at least one ICD-9-CM intervention code plasmapheresis or plasma exchange and at least one diagnosis code with rheumatic disease. All of them were hospitalized to Chang Gung Memorial Hospital between 1st of January, 2000, and 31st of December, 2014.

Results

436 nonoverlapping patients had never received PE and/or PP before 1 Jan, 2000. Among all the patients, 350 received PE, 63 received PP, and 23 received both therapies. Female patients accounted for 85.09% of patients. The overall mortality rate was 4.65% in the PE subgroup, 4.76% with combination therapy, and 13.46% in the PP subgroup. There were 374 patients diagnosed as SLE, which is the majority of overall patients who received PE and/or PE. In multivariate analysis, PE was the sole independent factor predictor of survival in SLE subgroup patients (p = 0.02, exp(B) = 0.314, 95% CI 0.12–0.81).

Conclusions

We showed that both PP and PE were used in treating a variety of autoimmune disorders. Plasmapheresis was preferentially carried out in patients with peripheral neuropathy. In 374 lupus patients treated with either PE or PP, PE is superior to PP in reducing in-hospital mortality.

Increased level of B cell differentiation factor in systemic lupus erythematosus patients

Most autoimmune disease are driven by a dysfunction in T and B cells, but B cells are still an interesting area of research, perturbations in their development are implicated in autoimmune diseases. B cell differentiating factor (BCDF) plays a part in the differentiation of B cells. The aim was To assess the levels of BCDF, IgM and IgG in SLE patients and whether they have any peculiarity in the clinical context of SLE. Thirty six patients with SLE and 24 healthy volunteers as control were enrolled in the study. BCDF was measured using Sandwich ELISA, total human IgM and IgG were measured by calorimetric methods. The mean concentrations of BCDF and IgM were significantly higher in patients with SLE as compared with controls (P < 0.001 and P < 0.0001 respectively). No significant difference was observed as regard IgG. We observed positive correlation between BCDF and IgM (r = 0.281, P = 0.03), and between IgG and IgM, duration of the disease (r = 0.468, P = 0.004, r = 0.337, P = 0.008 respectively). Moreover we observed lower IgM level in patients with discoid lesion (P = 0.009) and lower IgG level in those with hematologic manifestations (P = 0.02). ROC analysis revealed area under curve (AUC) 0.861 for BCDF and 0.902 for IgM, they can delineate SLE from controls at a cut-off value of 98.5 pg/ml, and 18 mg/dl IgM respectively.

Conclusion

BCDF and IgM are increased in SLE patients and are promissing diagnostic markers for SLE.

Systemic Lupus Erythematosus is a Risk Factor for Complications in Total Joint Arthroplasty

Introduction

Systemic Lupus Erythematosus (SLE) has been associated with increased complications following hip and knee arthroplasty. The Purpose of this study was to determine the extent to which SLE is a risk factor in outcomes following total joint arthroplasty (TJA).

Methods

The nationwide inpatient sample was used to identify a cohort of 505,841 patients who had a total hip arthroplasty (THA) or total knee arthroplasty (TKA) between 2009-2011. Of these patients, 2,284 patients (0.45%) had been previously diagnosed with SLE. The impact of SLE on short-term TJA outcomes was determined using multivariate logistic regression. Differences in discharge destination and length of stay were also evaluated.

Results

SLE patients were more likely to have an all-cause medical complication, (OR 1.9, p<0.0001) and more likely to have an all-cause surgical complication (OR 1.3, p<0.0001). SLE patients were four times more likely to become septic in the post-operative period (OR 3.8, p<0.0487). SLE patients were more likely to have a genitourinary complication (OR 1.7, p<0.0001) and bleeding complications requiring transfusion (OR 2.1, p<0.0001). Patients with SLE also had an increased length of stay (0.38 days, p<0.0001) and increased probability of discharging to a facility (OR 2.1, p<0.0001).

Discussion

Patients with SLE had an increased rate of both medical and surgical all-cause complications. Patients were specifically found to be at higher risk for sepsis, genitourinary complications, and blood transfusions. Future risk adjustment models should include SLE as a contributor to medical and surgical complications in the postoperative period.

Total Hip Arthroplasty Outcomes: An 18-Year Experience in a Single Center: Is Systemic Lupus Erythematosus a Potential Risk Factor for Adverse Outcomes?

BACKGROUND

In patients with systemic lupus erythematosus (SLE), persistent joint activity and treatment with glucocorticoids are associated with musculoskeletal complications. About 30% of these patients become candidates for surgical treatment. The aim of this study was to evaluate postoperative outcomes after total hip arthroplasty (THA) in SLE patients.

METHODS

We performed a retrospective cohort study at a tertiary care center in Mexico City between 1995 and 2013. All patients with SLE who underwent THA during that period were included (n = 58). They were compared with 2 control groups, one from another inflammatory arthropathy (rheumatoid arthritis, n = 58) and other noninflammatory (osteoarthritis, n = 58), matched by gender and date of surgery. The primary outcome was the frequency of postoperative complications during follow-up.

RESULTS

We included 174 patients who underwent THA during the study period. Patients with SLE were younger (P < .0001), had a longer hospitalization stay (P = .001), and required more transfusions (P = .004). Global complications in THA in patients with SLE were more prevalent than rheumatoid arthritis (36.2% vs 15.5%, P = .029) and osteoarthritis (36.2% vs 5.1%, P < .0001) patients. After multivariate analysis, risk factors for THA complications were: SLE (hazard ratio 2.8, 95% confidence interval 1.2-6.8; P = .018) and low postoperative hemoglobin (hazard ratio 0.77, 95% confidence interval 0.73-0.83; P < .0001). Long-term complications after THA were similar among groups.

CONCLUSION

This is the largest single-center study regarding clinical outcomes after THA in SLE patients. Our data suggest that SLE is an independent risk factor for adverse postoperative outcomes, mainly immediate complications, but the long-term outcome is good enough to offer surgical treatment that will improve quality of life.

Hepcidin and Ferritin: Important Mediators in Inflammation Associated Anemia in Systemic Lupus Erythematosus Patients

Systemic Lupus Erythematosus is an autoimmune disease with female preponderance. Anemia is found in 50% of Systemic Lupus Erythematosus patients. This is a cross sectional case control study with 30 female Systemic Lupus Erythematosus patients having inflammation associated anemia (Hemoglobin < 10.0 gm/dl) and 30 age matched controls with the aim to measure serum hepcidin and ferritin levels, correlate and study their role as homeostatic regulators of iron metabolism and utility as markers. Serum transferrin, ferritin, iron, total iron binding capacity, hsCRP, liver enzymes and renal parameters were analyzed by using automated analyser. Hepcidin levels were estimated by Sandwich-ELISA method. There was significant decrease in Iron (p < 0.0001), Iron Binding capacity (p < 0.0001), Transferrin (p < 0.0001) in patients, and a significant increase in inflammatory markers: hs-CRP (p < 0.0001), ESR (p < 0.0001) compared to controls. Significant increase in both Hepcidin (p < 0.0001) and Ferritin (p < 0.0001) was observed in patients with significant positive correlation (r = 0.711) with each other. Additionally, ferritin and hepcidin significantly positively correlated with hs-CRP and ESR (r = 0.526, 0.735); (r = 0.427, 0.742) respectively. Negative correlation with hemoglobin, iron, total iron binding capacity and transferrin with hepcidin (r = - 0.80, - 0.307, - 0.553, - 0.584) and ferritin (r = -0.722, - 0.22, - 0.654, - 0.728) was observed respectively. On ROC analysis both hepcidin and ferritin has sensitivity of 96.7%, specificity of 100% at cut-off values of 110 and 49 respectively. AUC of hepcidin was 0.993 and ferritin was 0.978. We have established a positive linear correlation between Hepcidin and Ferritin levels in disease activity and the changes correlated with the inflammatory state and anemia in patients, making them important mediators and potential markers of inflammation associated anemia.

Autologous stem cell transplantation for systemic lupus erythematosus

Some patients with severe systemic lupus erythematosus do not respond to conventional immunosuppression or suffer severe side effects from such treatment. In order to explore the concept of immunoablationfollowed by haematopoieticstem cell transplantation(HSCT) or ‘rescue’, an internationalcollaboration has occurred over the past seven years. The European Group for Blood and Marrow Transplantation(EBMT) and The European League Against Rheumatism (EULAR) have analysed their collective phase I and II studies and found a remission rate (based on a reduction of the SLEDAI to < 3) in 66%, one-third of whom later relapsed to some degree. The most often used protocol was cyclophosphamide (CY) and G-CSF for mobilization and CY plus anti thymocyte globulin as conditioning. Procedure related mortality was 12% in this sick group of patients with major organ involvement. The North American, mostly single centre experience showed higher rates of remission and one procedure related death. Some relapse was also observed. Phase II studies designed to assess the role of post-HSCT maintenance therapy are being considered by the EBMT/EULAR group.

A case of aplastic anemia in a patient with systemic lupus erythematosus

Abstract A case of aplastic anemia with a 16-year history of systemic lupus erythematosus (SLE) is described. The diagnosis of aplastic anemia was established by bone marrow biopsy. Aplastic anemia is an extremely rare complication of SLE. The pathogenesis of aplastic anemia associated with SLE remains to be clarified.

Hematological presentation in systemic lupus erythematosus and its relationship with disease activity

Abnormalities of hematological system are very common in systemic lupus erythematosus (SLE). The aim of the study is to evaluate hematological findings in patients with SLE at the time of referral and their relationship with disease activity and organ involvement. The study was carried consecutive 115 patients, including 20 males and 85 females. Most of the cases had anemia at the time of presentation due to various etiologies. Anemia of chronic disease was seen in 46% and it was the most common encountered picture. The rate of hemolytic anemia was 28%, and Coombs' positivity rate was 22% among our patients. Leukopenia ( < 4.0 x 10(9)/l), neutropenia ( < 1.8 x 10(9)/l), and lymphopenia ( < 1.5 x 10(9)/l) rates were 57, 20, and 82%, respectively. Thrombocytopenia was seen in 40% for < 150 x 10(9)/l, 26% for < 100 x 10(9)/l, and 8% for < 50 x 10(9)/l. Of our patients, 10% had antiphospholipid syndrome (APS) at the time of diagnosis. Increased fibrinogen levels were observed in 35% without relating to disease activity. The rates of C3 and C4 hypocomplementemia were 86 and 64%, respectively, and both are closely correlated with the disease activity. Moreover, C3 hypocomplementemia was more prominent in cases with renal or serosal involvement. Leukopenia and hyperfibrinogenemia were more common in patients with skin/mucosal involvements. C3 hypocomplementemia, APS and elevated IgG levels were more common in our patients with renal involvement. SLE should be kept in mind while evaluating patients with mentioned hematological findings, especially in those with accompanying organ involvements.

Pure Red Cell Aplasia with Adult Onset Still's Disease

Adult Onset Still's Disease (AOSD) is a rare inflammatory syndrome mostly seen in young adults. Known for its wide range of clinical manifestations, AOSD often presents with nonremitting systemic signs and symptoms. Many rare case associations have been described with AOSD, but only few with pure red cell aplasia (PRCA). We are presenting a fourth known case of a young female adult with AOSD and PRCA in the literature.

Antibodies against carbonic anhydrase in patients with aplastic anemia

BACKGROUND/AIMS

Antibodies against carbonic anhydrase (CA) have been detected in patients with an aplastic anemia (AA)-like syndrome after autologous stem cell transplantation.

METHODS

We analyzed sera of 53 bona fide AA patients before and after treatment with anti-thymocyte globulin (ATG) or bone marrow transplantation for the presence of anti-CA antibodies.

RESULTS

Anti-CA antibodies were detected in 20 patients (38%) and were associated with older age at diagnosis of AA. Antibody-positive patients showed poor response to ATG treatment (complete response 14%) and inferior long-term survival (36% at 10 years), when compared to antibody-negative patients (complete response and 10-year survival both 64%). Two thirds of patients with antibodies at diagnosis of AA became antibody negative after treatment with ATG. Clearance of the antibody did not appear to be associated with hematological improvement.

CONCLUSION

Antibodies against CA are detected frequently at diagnosis of AA, and their presence identifies a subset of patients with poor response to immunosuppressive treatment.

Neutrophils in the pathogenesis and manifestations of SLE

Systemic lupus erythematosus (SLE) is an autoimmune disease of unclear etiology that affects mostly women of childbearing age. Profound abnormalities in both innate and adaptive immunity triggered by genetic and environmental factors are well documented to play an important part in the pathogenesis of SLE. Nonetheless, the role of neutrophils--the most abundant immune cell type--in the pathology of this disease has been unclear. Over the past decade, compelling evidence has emerged that implicates neutrophils in the initiation and perpetuation of SLE and also in the resultant organ damage frequently observed in patients with this disease. SLE-derived low-density granulocytes (LDGs) induce vascular damage and synthesize increased amounts of type I interferons and, as such, could play a prominent part in the pathogenesis of SLE. Furthermore, increased cell death and enhanced extracellular trap formation observed in SLE-derived neutrophils might have key roles in the induction of autoimmunity and the development of organ damage in patients with SLE. Together, these events could have significant deleterious effects and promote aberrant immune responses in this disease. This Review highlights the role of neutrophils in the pathogenesis of SLE, with a particular focus on the putative deleterious effects of LDGs and neutrophil extracellular trap formation.

Endothelial progenitor cell dysfunction in rheumatic disease

Rheumatic disease is characterized by inflammation and endothelial dysfunction, which contribute to accelerated atherosclerosis. Circulating endothelial progenitor cells (EPCs) can restore dysfunctional endothelium and thereby protect against atherosclerotic vascular disease. The number and function of EPCs are, however, affected in rheumatic diseases such as psoriatic arthritis, rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, and antineutrophil cytoplasmic autoantibody-associated vasculitis. rheumatic disease is often characterized by decreased numbers, and impaired function, of EPCs, although numbers of these cells might increase during the initial years of systemic sclerosis. Pioneering studies show that EPC dysfunction might be improved with pharmacological treatment. How best to restore EPC function, and whether achieving this aim can prevent long-term cardiovascular complications in rheumatic disease, remain to be established.

Haematopoietic and endothelial progenitor cells are deficient in quiescent systemic lupus erythematosus

BACKGROUND

Systemic lupus erythematosus (SLE) is associated with a high prevalence of cardiovascular disease. Circulating endothelial progenitor cells (EPCs) contribute to vascular regeneration and repair, thereby protecting against atherosclerotic disease. EPCs are derived from CD34+ haematopoietic stem cells (HSCs), which have an increased propensity for apoptosis in the bone marrow of patients with SLE.

AIM

To determine whether circulating HSCs and EPCs are reduced in SLE, contributing to an increased cardiovascular risk.

METHODS

Progenitor cells were sampled from 15 female patients with SLE in prolonged clinical remission from their disease and 15 matched healthy controls. HSC and CD34+KDR+ EPCs were quantified by flow cytometry. Annexin V staining was used to identify apoptotic cells.

RESULTS

Patients with SLE had reduced levels of circulating CD34+ HSCs and CD34+KDR+ EPCs, associated with increased HSC apoptosis. Compared with controls, the fraction of HSCs that could be identified as EPCs was higher in patients with SLE, consistent with a primary defect of HSCs. EPC outgrowth from mononuclear cells, which depends mainly on CD34- cells, was unaffected.

CONCLUSIONS

Patients with SLE have lower levels of circulating HSCs and EPCs, even during clinical remission. The data suggest that increased HSC apoptosis is the underlying cause for this depletion. These observations indicate that progenitor cell-mediated endogenous vascular repair is impaired in SLE, which may contribute to the accelerated development of atherosclerosis.

Primary and secondary autoimmune neutropenia

Antineutrophil antibodies are well recognized causes of neutropenia, producing both quantitative and qualitative defects in neutrophils and increased risk for infection. In primary autoimmune neutropenia (AIN) of infancy, a moderate to severe neutropenia is the sole abnormality; it is rarely associated with serious infections and exhibits a self-limited course. Chronic idiopathic neutropenia of adults is characterized by occurrence in late childhood or adulthood, greater prevalence among females than among males, and rare spontaneous remission. Secondary AIN is more commonly seen in adults and underlying causes include collagen disorders, drugs, viruses and lymphoproliferative disorders. In most patients with AIN, antibodies recognize antigens located on the IgG Fc receptor type 3b but other target antigens have been recently identified in secondary AIN. Granulocyte colony-stimulating factor is a proven treatment in patients with AIN of all types and is now preferred to other possible therapies.

Anaemia in systemic lupus erythematosus: from pathophysiology to clinical assessment

Haematological abnormalities are common in systemic lupus erythematosus. Anaemia is found in about 50% of patients, with anaemia of chronic disease being the most common form. Impaired erythropoietin response and presence of antibodies against erythropoietin may contribute to the pathogenesis of this type of anaemia. Patients with autoimmune haemolytic anaemia usually belong to a distinct category, which is associated with anticardiolipin antibodies, thrombosis, thrombocytopenia, and renal disease, often in the context of secondary antiphospholipid syndrome. Autoantibodies, T lymphocytes, and deregulation of the cytokine network can affect bone marrow erythropoiesis, leading to anaemia.

Stem cell transplantation in systemic lupus erythematosus

Systemic lupus erythematosus is a heterogeneous, multisystem disease responsive to treatment with corticosteroids and immune suppressives. Many patients fail to achieve treatment-free remissions, and their long-term outcomes remain poor owing to the development of vital organ failure, cumulative drug toxicity and an increased risk of cardiovascular disease and malignancy. Haematopoietic stem cell transplantation (HSCT) offers the potential to improve long-term outcome in those with a poor prognosis. Preliminary phase II and registry studies have usually employed non-myeloablative conditioning with positive CD34 cell selection. They have highlighted the potential efficacy and dangers of HSCT. Patient selection is important but complex, and the influence of HSCT on long-term outcome is unknown. Disease relapse occurs in up to one-third of patients after HSCT, but the consequences of relapse and the role of remission-maintenance strategies are unknown. With the availability of other alternative therapies in refractory disease, there needs to be a clear demonstration of the benefits of HSCT from current randomized trials.

Congenital and Acquired Neutropenia

Our understanding of the pathogenesis of congenital and acquired neutropenia is rapidly evolving. New ground-breaking observations have identified the genes responsible for many of the congenital neutropenia syndromes and are also providing new insights into normal neutrophil commitment and differentiation. Acquired neutropenia remains a poorly understood syndrome, although new insights into its pathogenesis are also emerging, especially with regard to subsets of immune neutropenia.

In Section I, Dr. Marshall Horwitz reviews the current understanding of the genetic basis, molecular pathology, and approaches to treatment of congenital neutropenia and cyclic hematopoiesis. Mutations in the ELA2 gene, which encodes for neutrophil elastase, cause cyclic hematopoiesis. ELA2 mutations are also the most common cause of congenital neutropenia, where their presence may equate with a more severe clinical course and higher frequency of leukemic progression. Emerging evidence indicates interrelatedness with Hermansky Pudlak syndrome and other disorders of neutrophil and platelet granules.

In Section II, Dr. Nancy Berliner presents an overview of the clinical approach to the evaluation and treatment of acquired neutropenia. This includes a review of the pathogenesis of primary and secondary immune neutropenia, drug-induced neutropenia, and non-immune chronic idiopathic neutropenia of adults. Studies used to evaluate patients for potential immune neutropenia are reviewed. Management issues, especially the use of granulocyte colony-stimulating factor (G-CSF), are discussed.

In Section III, Dr. Thomas Loughran, Jr., reviews the pathogenesis and clinical manifestations of large granular lymphocyte (LGL) leukemia. Possible mechanisms of neutropenia are discussed. In particular, discussion focuses on the relationship between LGL leukemia, rheumatoid disease, and Felty’s syndrome, and the complex interplay of defects in neutrophil production, distribution, destruction, and apoptosis that underly the development of neutropenia in those syndromes.

Apoptosis of CD34+ cells after incubation with sera of leukopenic patients with systemic lupus erythematosus

Leukopenia and anaemia are observed in about a fifth of all patients with systemic lupus erythematosus (SLE) and may be due either to the destruction of blood cells or their decreased production. The former may be humoral or cell-mediated or result from apoptosis of peripheral blood cells. Several observations suggest the occurrence of the latter reduced in vitro proliferation of pluripotent bone marrow progenitors from the bone marrow aspirates of SLE patients,reduced counts of CD34+ cells in bone marrow aspirates in SLE patients, apoptosis of lymphopoietic progenitors and apoptosis of bone marrow cells. The aim of our study was to investigate whether humoral factors may induce suppression of haematopoiesis by increased apoptosis of CD34+ cells. For this purpose, we incubated allogeneic CD34+-enriched cells with sera of 18 leukopenic SLE patients. Apoptosis was induced by four of 18 sera. This effect was independent of complement-inhibition and FAS-blockade. Although reduced proliferation of autologous pluripotent bone marrow progenitors has been attributed to an IgG serum inhibitor, removal of IgG from these four proapoptotic sera had no effect on apoptosis of allogeneic CD34+ cells. The proapoptotic effect was associated with high titres of anti-dsDNA antibodies and low haemoglobin concentrations, but not with high titres of antinuclear antibodies, TNF-alpha and IFN-alpha of the sera tested.

Serum thrombopoietin levels and anti-thrombopoietin antibodies in systemic lupus erythematosus

Thrombocytopenia is a common phenomenon in patients suffering from systemic lupus erythematosus (SLE). The cause of thrombocytopenia in SLE, however, is poorly understood. In this study, 100 patients with SLE were evaluated for serum thrombopoietin levels, anti-thrombopoietin antibodies and routine laboratory parameters such as peripheral blood counts, parameters of blood chemistry and immunologic parameters of SLE. The median platelet count of SLE patients was 230 g/l and 19 were thrombocytopenic (range 8-148 g/l). Thrombopoietin levels in SLE patients were found to be significantly higher than in healthy controls (n = 96; median, 117 pg/ml vs 64 pg/ml, P < 0.01). When excluding thrombocytopenic SLE patients, thrombopoietin levels in SLE were still above controls (111 pg/ml, P < 0.01). The thrombopoietin levels were correlated to erythrocyte sedimentation rate and ECLAM score of disease activity, and inversely correlated to complement factor C4, but not to the platelet count. Anti-thrombopoietin antibody reactivity was found in 23% of SLE patients. Interestingly, these patients had lower platelet counts than SLE patients without anti-thrombopoietin antibodies (median 174 g/l and 253 g/l, respectively, P < 0.01), but thrombopoietin levels were not significantly different. Taken together, thrombopoietin levels are significantly higher in the sera of SLE patients than in healthy controls and anti-thrombopoietin antibodies are frequently found.

Autoantibodies against granulocyte colony-stimulating factor in Felty's syndrome and neutropenic systemic lupus erythematosus

OBJECTIVE

Cytokines and growth factors can be a target of autoantibodies in systemic inflammatory diseases. We examined whether patients with neutropenia and either Felty's syndrome (FS) or systemic lupus erythematosus (SLE) have autoantibodies against granulocyte colony-stimulating factor (G-CSF) and whether these autoantibodies are functionally relevant.

METHODS

Fifteen patients with neutropenia due to FS were matched for age, sex, and disease activity with 16 normocytic rheumatoid arthritis (RA) control patients. Sixteen patients with SLE and neutropenia were matched with 16 normocytic SLE control patients. Antibodies against G-CSF were measured by enzyme-linked immunosorbent assay and Western blotting. Antibody specificity was verified by competitive inhibition using recombinant human G-CSF. The effect of anti-G-CSF antibodies on the functional activity of their target molecule was measured in a bioassay using G-CSF-sensitive murine 32D cells.

RESULTS

IgG anti-G-CSF was found in 11 FS patients, 6 SLE patients with neutropenia, 6 SLE control patients, and none of the RA control patients. IgM anti-G-CSF was found in 6 neutropenic and 3 normocytic SLE patients. Anti-G-CSF antibodies were associated with an exaggerated serum level of G-CSF and a low neutrophil count. A neutralizing effect of anti-G-CSF antibodies on its target molecule was found in 3 of the 9 patients tested. Irrespective of the presence or absence of anti-G-CSF antibodies, neutropenic patients with FS and SLE had exaggerated serum levels of G-CSF.

CONCLUSION

Anti-G-CSF autoantibodies are common in neutropenia due to FS and SLE. In individual patients, these autoantibodies have a neutralizing capacity. In patients without neutralizing antibodies, hyposensitivity of the myeloid cells to G-CSF appears to be central to the pathogenesis of the neutropenia in FS and SLE.

Chronic neutropenia associated with autoimmune disease

Chronic neutropenia with autoimmune diseases is associated mainly with rheumatoid arthritis (RA), as Felty's syndrome or large granular lymphocyte (LGL) leukemia, and with systemic lupus erythematosus (SLE). Recent advances have allowed better understanding regarding the mechanism of neutropenia and improved options for treatment. Target antigens for antineutrophil antibodies have been identified for both Felty's syndrome and for SLE. The role of soluble Fas-ligand (FasL) in inducing apoptosis of neutrophils has been clarified for LGL leukemia and increased neutrophil apoptosis has been described in neutropenic patients with SLE. The role of immune complexes in affecting neutrophil traffic and function continues to be studied. Treatments of neutropenia have included methotrexate, cyclosporine A, and granulocyte colony-stimulating factor (G-CSF) as well as granulocyte-macrophage colony-stimulating factor (GM-CSF). The efficacy of both GM- and G-CSF in reversing neutropenia and decreasing the risk of infections in Felty's syndrome and SLE has been well documented. Of concern, however, have been flares of symptoms or development of leukocytoclastic vasculitis in some patients following the use of these cytokines. Recent results suggest that in these patients G-CSF should be administered at the lowest dose effective at elevating the neutrophil count above 1,000/microL.

Bone marrow stem cells and stromal cells in autoimmune cytopenias

High-dose immunosuppression followed by autologous haemopoietic stem cell transplantation (ASCT) is a promising practice for the treatment of severe, resistant autoimmune disorders. Patients with refractory autoimmune cytopenias (AIC), primary or secondary to systemic autoimmune diseases (AID) including systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), have been proposed as potential candidates for such a therapeutic procedure. An abnormal immune milieu, however, may affect the number and functional characteristics of stem cells and/or stromal cells in the bone marrow (BM) and might impact on harvesting and engraftment potential of stem cells or on BM reconstitution following engraftment in patients with AIC undergoing ASCT. Using flow cytometry and in vitro culture assays we have shown that patients with primary AIC display increased number of BM CD34+ cells in response to abnormally high production of granulocyte-colony stimulating factor (G-CSF) by BM stroma. In contrast, patients with AIC secondary to systemic AID display increased apoptosis of BM progenitor cells resulting in low CD34+ cell numbers and abnormal haemopoiesis supporting capacity of BM stroma due to the aberrant, local or systemic, inhibitory cytokine production or to intricate interactions between haemopoietic and immune cells present within the BM microenvironment. In this review we summarize the available knowledge on BM stem cell reserve and function and stromal cell function in patients with primary and secondary AIC with special reference to SLE and RA. The underlying mechanisms possibly involved in the pathogenesis of the observed abnormalities are also discussed.

Increased apoptosis of bone marrow CD34(+) cells and impaired function of bone marrow stromal cells in patients with systemic lupus erythematosus

The changes in bone marrow (BM) stem cell reserve and function and stromal cell function in patients with active systemic lupus erythematosus (SLE) were investigated. The study was carried out on seven SLE patients and 28 healthy controls using flow cytometry and in vitro cell culture assays. We found that patients had low CD34(+) cells, compared with the control group, reflecting the decrease of both CD34(+)/CD38(-) and CD34(+)/CD38(+) cells. Patient CD34(+)/Fas(+) but not CD34(-)/Fas(+) cells were significantly increased. Apoptotic (7AAD(dim)) cells were higher among CD34(+)/Fas(+) than among CD34(+)/Fas(-) cells, and individual values of apoptotic CD34+ cells strongly correlated with the number of CD34(+)/Fas(+) cells. These findings are suggestive of a Fas-mediated apoptosis accounting for the low CD34(+) cells in SLE patients. Moreover, we found that patients had low numbers of granulocyte-macrophage colony-forming units (CFU-GM) and erythroid burst-forming units (BFU-E), compared with the control group, and that the generation of colony-forming cells in long-term BM cultures was significantly reduced. Patient BM stroma failed to support allogeneic progenitor cell growth. In one patient, CD34(+) cells were increased, apoptotic CD34(+)/Fas(+) cells were normalized and defective stromal cell function was restored after autologous stem cell transplantation. We concluded that defective haemopoiesis in SLE patients is probably caused, at least in part, to the presence of autoreactive lymphocytes in BM.

Myelofibrosis in systemic lupus erythematosus

In this study we present a case of coexisting systemic lupus erythematosus (SLE) and myelofibrosis. Literature review supports the fact that the two diseases rarely occur together in the same patient. The young female patient studied was admitted with pancytopenia and a clinical picture which met the criteria of SLE. Histological examination of the bone marrow biopsy revealed severe myelofibrosis with hypocellularity of the myeloid cell lines. Treatment with immunosuppressive and colony stimulating factor led to slow but complete regeneration of the bone marrow and subsequently to an improved haematological status, and the patient was spared bone marrow transplantation.

Altered bone marrow cell sensitivity in the lupus-prone NZB/W mouse: regulation of CFU-GM colony formation by estrogen, tamoxifen and thrombopoietin

Estrogen is thought to contribute to the onset of systemic lupus erythematosus (SLE) in women through mechanisms that are not completely understood. Although estrogen serves as a negative regulator in normal hematopoietic development, little research has been conducted examining alteration in hematopoietic development triggered by estrogen in lupus-susceptible individuals. We examined whether estrogen and other factors could influence colony formation of bone marrow cells obtained from normal and lupus-susceptible mice. Bone marrow cells isolated from New Zealand Black (NZB) and lupus-prone New Zealand Black and New Zealand White cross (NZB/W) mice were cultured in the presence of granulocyte-macrophage colony stimulating factor (GM-CSF) alone or in combination with estrogen, thrombopoietin (TPO), tamoxifen, estrogen and TPO. or estrogen and tamoxifen, and plated in methylcellulose culture medium. Plates were scored for the number of CFU-GM (colony forming unit granulocyte-macrophage) colonies after 6d in culture. For females of both mouse strains, estrogen significantly decreased (P < 0.05) the number of GM colonies. Co-treatment of NZB/W cells, but not NZB cells, with TPO or tamoxifen reversed the suppressive action of estrogen (P < 0.05). In contrast, while estrogen did suppress colony formation from cells of NZB/W males (P < 0.05), neither TPO nor tamoxifen reversed this effect. Our results indicate that the sensitivity of bone marrow cells isolated from both female and male NZB/W lupus-prone mice to hormones/growth factors is qualitatively different from cells of NZB mice, and suggest that hematopoietic alterations at the level of the bone marrow may be related to the pathogenesis of SLE.

Dyserythropoiesis associated with a fas-deficient condition in childhood

Defective lymphocyte apoptosis caused by mutations of the Fas gene can result in an autoimmune lymphoproliferative syndrome (ALPS) in humans. We report two cases of dyserythropoiesis associated with a Fas-deficient condition in childhood. In both cases, dyserythropoiesis predominated on the more mature erythroblasts, and was associated with a lymphoproliferative syndrome as well as with haemolytic anaemia, hypergammaglobulinaemia and the expansion of an unusual population of CD4- CD8- T cells that express the alpha/beta T-cell receptor. The regression of dyserythropoiesis under steroid therapy suggested that it resulted from an autoimmune mechanism, itself secondary to the lymphocyte Fas apoptosis deficiency. Fas-defective apoptosis may be a new aetiology for childhood dyserythropoiesis.

Treatment of severe neutropenia due to Felty's syndrome or systemic lupus erythematosus with granulocyte colony-stimulating factor

OBJECTIVES

To examine the efficacy and safety of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) for the treatment of severe neutropenia due to Felty's syndrome (FS) or systemic lupus erythematosus (SLE).

METHODS

Eight patients with absolute neutrophil counts (ANC) below 1,000/microL attributable to FS (n = 4) or SLE (n = 4) were treated with rhG-CSF. The hematologic and clinical response as well as side effects were recorded. In addition, reports on the use of rhG-CSF/rhGM-CSF in FS and SLE retrieved from the English language literature were analyzed.

RESULTS

RhG-CSF effectively corrected neutropenia due to FS and SLE in seven of the current eight patients. In 54 of 55 FS and SLE patients retrieved from the literature, G-CSF or GM-CSF, respectively, proved to be effective at elevating the neutrophil count, which was often associated with improvement of infectious complications. The neutrophil count often declined again when growth factor treatment was stopped but generally stabilized at a level that exceeded the pretreatment count. Side effects included rare cases of thrombocytopenia, arthralgias, and development of cutaneous leukocytoclastic vasculitis. Side effects were dose dependent and resolved when treatment was discontinued. One of our own patients and 17 previously reported patients continued to benefit from long-term administration of rhG-CSF over periods of more than 40 months.

CONCLUSIONS

RhG-CSF is an effective and generally well-tolerated treatment for neutropenia due to FS or SLE. Exacerbation of the underlying rheumatic condition due to G-CSF appears to be rare if G-CSF is administered at the lowest dose effective at elevating the ANC above 1,000/microL.

Hepatic extramedullary granulopoiesis after treatment with liver-stimulatory xenobiotics, in lpr mice

This study demonstrates that extramedullary hematopoiesis occurs in livers of adult lpr mice and, after treatment with each of three xenobiotic compounds--phenobarbital, cyproterone acetate, and nafenopin--it includes granulopoiesis. lpr mice are used as a model of the human disease systemic lupus erythematosus (SLE). The develop a syndrome very similar to that of human sufferers. In untreated lpr mice, mononuclear white blood cells were discernible in hepatic sinusoidal foci; T and B lymphocytes were distinguished from each other by immunocytochemistry at light microscope level. After treatment with any of the xenobiotic compounds, immunolabeling demonstrated the additional presence of granulocytes in foci, and, at electron microscope level neutrophils, eosinophils and their precursors were clearly recognizable.

[A case of post-partum remission of acquired dyserythropoiesis, a rare cause of anemia in disseminated lupus erythematosus]

INTRODUCTION

Amongst the various causes of anemia in systemic lupus erythematosus, isolated and acquired erythrocyte dysplasia is rare and most often part of global dysmyelopoiesis.

EXEGESIS

The authors report a case of acquired erythrocyte dysplastic syndrome that occurred in a 34-year-old woman in whom previous diagnosis had evidenced systemic lupus erythematosus of rather benign course. Other causes of dysmyelopoiesis were ruled out. Myeloid stem cell cultures showed selective inhibition of erythroid cells growing, with no particular effect of the patient's serum. While a corticosteroid treatment with prednisone (1 mg/kg/d) did not show any efficacy upon anemia, the patient's pregnancy was followed by prolonged correction of hemoglobin, making possible the tapering of prednisone down to 10 mg/d.

CONCLUSION

Acquired erythrocyte dysplastic syndrome remains a rare cause of anemia in systemic lupus erythematosus. This case report suggests an immunological phenomenon, but the mechanisms underlying both the appearance and long-lasting remission after pregnancy remain unexplained.

Autoantibodies to human recombinant erythropoietin in patients with systemic lupus erythematosus: correlation with anemia

OBJECTIVE

To investigate the existence of circulating autoantibodies to erythropoietin (EPO) in sera from patients with systemic lupus erythematosus (SLE), and to correlate their presence with anemia and clinical activity.

METHODS

Ninety-two consecutive patients with SLE, 80 patients with rheumatoid arthritis, and 42 normal individuals were studied. The patients with SLE were categorized into 3 groups according to hemoglobin (Hgb) level: group A (45 patients with Hgb > 12 gm/dl), group B (26 patients with Hgb 10.1-12 gm/dl), and group C (21 patients with Hgb < or = 10 gm/dl). In all patients with SLE, the disease activity was evaluated using the European Consensus Lupus Activity Measurement scale. Antibodies to EPO were detected using an enzyme-linked immunosorbent assay and purified recombinant human EPO as antigen. The specificity of the method was evaluated with homologous and cross-reactive inhibition assays.

RESULTS

Antibodies to EPO were found in 15.2% of the SLE patient sera. The distribution of these antibodies among the 3 groups of SLE patients was as follows: 8.8% (4 of 45) from group A, 15.4% (4 of 26) from group B, and 28.6% (6 of 21) from group C. The prevalence of antibodies to EPO in patients with severe anemia (group C) was statistically significantly higher compared with patients without anemia (chi(2) = 4.31, P < 0.05). Patients with antibodies to EPO had higher disease activity scores (P < 0.005) and lower levels of the C4 component of complement (P < 0.05) compared with patients without antibodies to EPO.

CONCLUSION

In this study, the presence of antibodies to EPO in the sera of SLE patients is demonstrated for the first time. The presence of these antibodies is associated with severe anemia and active disease.

Antithymocyte globulin for a patient with systemic lupus erythematosus complicated by severe pancytopenia

The clinical use of antithymocyte globulin is rarely reported in patients with rheumatic diseases. We describe the use of this agent in a patient with systemic lupus erythematosus who concomitantly developed severe pancytopenia. High-dose methylprednisolone therapy had been unsuccessful in controlling either the disease exacerbation or the pancytopenia. Antithymocyte globulin and cyclosporin A were therefore administered to achieve immunosuppression. The exacerbation of disease activity was gradually lessened, except for persistent thrombocytopenia and anaemia. Severe and persistent immunosuppression, however, led to a fatal brain abscess. The combined use of both antithymocyte globulin and cyclosporin A induced potent immunosuppression, and should be confined to selected patients with systemic lupus erythematosus, and administered under detailed monitoring.