The utility of therapeutic plasma exchange in Hyperviscosity syndrome associated with juvenile rheumatoid arthritis: A case report.

Hyperviscosity syndrome (HVS) is a life-threatening syndrome caused by high concentrations of large plasma proteins like IgM, rheumatoid factor, and other immune complexes, leading to increased blood viscosity and symptoms such as visual abnormalities, neurological impairment, bleeding diathesis, and thrombosis. While Waldenström's macroglobulinemia accounts for 80% to 90% of cases, HVS may develop in other clinical settings characterized by elevations in plasma proteins. Limited evidence currently exists describing the safety and efficacy of therapeutic plasma exchange (TPE) for the management of HVS secondary to non-neoplastic conditions. We report a case of recurrent HVS associated with juvenile rheumatoid arthritis and Felty syndrome that demonstrated improvement in clinical symptoms following initiation of TPE. These findings suggest that TPE may be utilized as an adjunct treatment option in patients with HVS secondary to autoimmune disorders.

Tocilizumab treatment in Felty's syndrome.

Felty's syndrome (FS) is a deforming disease, characterized by the triad of rheumatoid arthritis (RA), neutropenia, and splenomegaly. Currently, FS patients are treated mainly with immunosuppressants, such as methotrexate and glucocorticoids, which however are not suitable to some patients and may cause severe side effects. Here we report a clinical FS case that was treated with Tocilizumab (TCZ) successfully. The patient had symmetrical swelling and pain of multiple joints, deformity of elbow joints with obvious morning stiffness. Joint color Doppler ultrasound showed synovial hyperplasia and bone erosion of wrist and proximal interphalangeal joints and CT scan suggested splenomegaly. Further examination showed neutropenia and anemia, a high titer of anti-cyclic citrullinated peptide antibody, rheumatoid factor and anti-nuclear antibodies, positive p-ANCA, and elevated IgA and IgG. After treating with TCZ, the patient has been relieved of clinical symptoms. His spleen has recovered to normal size. The absolute neutrophil count (ANC) tended to be stable, and joint erosion did not deteriorate. We have reviewed the literatures on FS treatment with biological agents and found only a few reports using TNF-α antagonist and rituximab treating FS, but none with TCZ. So, it is the first time to report a successful FS case treated with TCZ. This case suggests that the TCZ may be a new choice for FS treatment, under the condition of closely monitoring the ANC.

Neutropaenia and splenomegaly without arthritis: think rheumatoid arthritis.

Felty syndrome(FS) is an uncommon, but severe, extra-articular manifestation of rheumatoid arthritis (RA). It occurs in patients with longstanding RA. It is extremely rare for RA to present as FS or develop after initially presenting as neutropaenia and splenomegaly. We describe a case of 47-year-old woman who was diagnosed simultaneously with FS and possible RA after testing positive for anticyclic citrullinated peptide antibody, but a negative rheumatoid factor. She had an excellent response to methotrexate. We review the existing literature of such cases and emphasise the importance of serological testing for RA in patients presenting with neutropaenia and splenomegaly, even in the absence of joint symptoms or prior diagnosis of RA.

Treatment of pseudo Felty's syndrome: Is there a place for rituximab?

OBJECTIVE: Pseudo Felty's syndrome (PFS) is an uncommon syndrome occurring in Rheumatoid Arthritis and characterized by a monoclonal expansion of lymphocytes with neutropenia. Methotrexate is the first line recommended treatment. In case of incomplete response, cyclophosphamide may be used for hematological features but does not share the same efficacy on arthritis. We investigate the effect of rituximab in PFS as second line treatment. METHODS: This is a retrospective study about six cases of PFS treated with methotrexate and/or rituximab. RESULTS: Five women and 1 man (mean age: 66 years) were included. All patients were positive for rheumatoid factor and five were anti CCP positive. All patients presented bone erosions, three had splenomegaly. The disease duration was between 0 and 19 years at large granular lymphocyte (LGL) leukemia diagnosis. Methotrexate was effective and well tolerated for two patients with a follow up of 7 and 4 years. For a third patient, the hematological symptoms were predominant and he received after methotrexate, several infusions of cyclophosphamide. Three patients (2 T-cell and 1 NK-cell LGLL) were treated with rituximab (two 1000 mg infusions) with a decreased DAS28 and an increased neutrophil count, with subsequent courses of rituximab one to three years later with the same efficacy. This treatment was well tolerated without infectious events after a follow up of one and three years. CONCLUSION: Methotrexate is effective in near half of cases of PFS. In second line, rituximab may be a therapeutic option with good efficacy and tolerance.

Acquired inhibitors to factor VIII and fibrinogen in the setting of T-cell large granular lymphocyte leukemia: a case report and review of the literature.

Large granular lymphocyte (LGL) leukemia is an indolent lymphoproliferative malignancy which dysregulates humoral immunity and underlies the myriad autoimmune phenomena. We describe a 62-year-old woman with Felty's syndrome who developed a severe bleeding diathesis. Laboratory evaluation demonstrated acquired inhibitors to both factor VIII (FVIII) and fibrinogen, likely secondary to T-cell LGL leukemia. After a complicated course, the patient's inhibitors were extinguished with rituximab and high-dose corticosteroids. Bleeding was controlled with alternating FEIBA (factor eight inhibitor bypassing activity) and recombinant activated FVII. This report reviews the literature comparing the efficacy of various treatment modalities for both disorders. To our knowledge, this is the first reported case of a patient with LGL leukemia acquiring an inhibitor to FVIII or fibrinogen.

Felty's syndrome and hypofibrinogenemia: an unusual target for anti-cyclic citrullinated peptide antibodies?

BACKGROUND: Rheumatoid arthritis (RA) is a risk factor for the development of Felty's syndrome and large granular lymphocyte (LGL) leukemia. Anti-cyclic citrullinated peptide (CCP) antibodies are considered highly specific for RA and are directed against various citrullinated antigens, including citrullinated fibrinogen. Anti-CCP antibodies may interfere with the detection of citrullinated proteins and their function. In this article, we describe the possible inhibition of fibrinogen by anti-CCP antibodies with clinical consequences which have never been reported in the literature to our best knowledge. CASE REPORT: We present the case of a 79-year-old Caucasian woman with a longstanding history of untreated seropositive RA and who had been investigated for severe neutropenia since several months. The association of splenomegaly led to suspicion of Felty's syndrome. Flux cytometry was compatible with T-cell LGL leukemia. In addition, severe hypofibrinogenemia was detected. The later finding has not been consistently associated with the former clinical entities. Further investigations demonstrated that the anti-CCP antibodies of the patient also recognized the P41 peptide of citrullinated fibrinogen. The patient deceased of intracranial hemorrhage. CONCLUSION: It is likely, yet not definite, that high anti-citrullinated fibrinogen titers may contribute to low fibrinogen levels and could have contributed to the fatal hemorrhagic event.

Citrullination of autoantigens implicates NETosis in the induction of autoimmunity.

Tolerance blocks the expression of autoantibodies, whereas autoimmunity promotes it. How tolerance breaks and autoantibody production begins thus are crucial questions for understanding and treatment of autoimmune diseases. Evidence implicates cell death and autoantigen modifications in the initiation of autoimmune reactions. One form of neutrophil cell death called NETosis deserves attention because it requires the post-translational modification of histones and results in the extracellular release of chromatin. NETosis received its name from NET, the acronym given to Neutrophil Extracellular Trap. The extracellular chromatin incorporates histones in which arginines have been converted to citrullines by peptidylarginine deiminase IV (PAD4). The deiminated chromatin may function to capture or 'trap' bacterial pathogens, thus generating an extracellular complex of deiminated histones and bacterial cell adjuvants. The complex of bacterial antigens and deiminated chromatin may be internalised by host phagocytes during acute inflammatory conditions, as arise during bacterial infections or chronic autoinflammatory disorders. The uptake and processing of deiminated chromatin together with bacterial adjuvants by phagocytes may induce the presentation of modified histone epitopes and co-stimulation, thus yielding a powerful stimulus to break tolerance. Autoantibodies to deiminated histones are prevalent in Felty's syndrome patients and are present in systemic lupus erythematosus (SLE) and patients with rheumatoid arthritis (RA). These observations clearly implicate histone deimination as an epigenetic mark that can act as an autoantibody stimulant.

Autoimmune manifestations in large granular lymphocyte leukemia.

Large granular lymphocyte (LGL) leukemia features a group of indolent lymphoproliferative diseases that display a strong association with various autoimmune conditions. Notwithstanding, these autoimmune conditions have not been comprehensively characterized or systematized to date. As a result, their clinical implications remain largely unknown. The authors offer a comprehensive review of the existing literature on various autoimmune conditions documented in the course of T-cell LGL (T-LGL) leukemia. Though some of them are thought be secondary to the LGL leukemia, others could be primary and might even play a role in its pathogenesis. A considerable clinico-laboratory overlap between T-LGL leukemia associated with rheumatoid arthritis and Felty's syndrome suggests that they are just different eponyms for the same clinical entity.

Neutrophil activation and B-cell stimulation in the pathogenesis of Felty's syndrome.

Felty's syndrome (FS) is a severe arthritic disorder that features chronic neutrophil activation and progresses to neutropenia and susceptibility to unabated infections. The life­threatening manifestations of FS have focused the attention of clinical experimenters who have made persistent efforts to find new and effective therapies. This review highlights important milestones in the research on FS and draws attention to recent studies on the antigen specificity of antibodies present in patients' sera. Recent data have indicated that immunoglobulins G (IgGs) in patients with FS bind selectively and specifically to deiminated histones and neutrophil extracellular chromatin traps (NETs). Deimination is the conversion of certain arginine residues in proteins to citrullines by the enzyme peptidylarginine deiminase 4. Earlier observations had indicated that IgGs in FS patients avidly bind to citrullinated peptides. These observations suggest that NETosis, the type of cell death that is defined by the release of NETs, provides autoantigens that stimulate B cell responses in this patient group. This insight parallels recent observations in other autoimmune conditions and lends support to the paradigm that NETosis plays a leading role in the pathogenesis of antiself immune responses. 

Felty's syndrome autoantibodies bind to deiminated histones and neutrophil extracellular chromatin traps.

OBJECTIVE: To test the hypothesis that autoantigen modifications by peptidylarginine deiminase type 4 (PAD-4) increase immunoreactivity. METHODS: We assembled sera from patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Felty's syndrome (FS), and antineutrophil cytoplasmic antibody-associated vasculitides (AAVs), as well as sera from control subjects without autoimmune diseases. The sera were tested for binding to activated neutrophils, deiminated histones, and neutrophil extracellular chromatin traps (NETs). IgG binding to lipopolysaccharide-activated neutrophils was assessed with confocal microscopy, and binding to in vitro-deiminated histones was measured using enzyme-linked immunosorbent assay (ELISA) and Western blotting. In addition, we quantitated histone deimination in freshly isolated neutrophils from the blood of patients and control subjects. RESULTS: Increased IgG reactivity with activated neutrophils, particularly binding to NETs, was paralleled by preferential binding to deiminated histones over nondeiminated histones by ELISA in a majority of sera from FS patients but only in a minority of sera from SLE and RA patients. Immunoblotting revealed autoantibody preference for deiminated histones H3, H4, and H2A in most FS patients and in a subset of SLE and RA patients. In patients with AAVs, serum IgG preferentially bound nondeiminated histones over deiminated histones. Increased levels of deiminated histones were detected in neutrophils from RA patients. CONCLUSION: Circulating autoantibodies in FS are preferentially directed against PAD-4-deiminated histones and bind to activated neutrophils and NETs. Thus, increased reactivity with modified autoantigens in FS implies a direct contribution of neutrophil activation and the production of NET-associated nuclear autoantigens in the initiation or progression of FS.

The spectrum of large granular lymphocyte leukemia and Felty's syndrome.

PURPOSE OF REVIEW: Patients with chronic large granular lymphocyte (LGL) leukemia often have rheumatoid arthritis (RA), neutropenia and splenomegaly, thereby resembling the manifestations observed in patients with Felty's syndrome, which is a rare complication of RA characterized by neutropenia and splenomegaly. Both entities have similar clinical and laboratory presentation, as well as a common genetic determinant, HLA-DR4, indicating they may be part of the same disease spectrum. This review paper seeks to discuss the underlying pathogenesis and therapeutic algorithm of RA, neutropenia and splenomegaly in the spectrum of LGL leukemia and Felty's syndrome. RECENT FINDINGS: We hypothesize that there may be a common pathogenic mechanism between LGL leukemia and typical Felty's syndrome. Phenotypic and functional data have strongly suggested that CD3 LGL leukemia is antigen-activated. Aberrations in the T-cell repertoire with the emergence of oligoclonal/clonal lymphoid populations have been found to play a pivotal role in pathogenesis of RA. The biologic properties of the pivotal T cell involved in RA pathogenesis are remarkably similar to those in leukemic LGL. SUMMARY: RA-associated T-cell LGL leukemia and articular manifestations of typical Felty's syndrome are not distinguishable. A common pathogenetic link between LGL leukemia and RA is proposed.

High avidity cytokine autoantibodies in health and disease: pathogenesis and mechanisms.

Numerous reports have documented the presence of autoantibodies working against naturally occurring cytokines in humans in health and disease. In most instances, their physiological and pathophysiological significance remains unknown. However, recent advances in the methodologies for detecting cytokine autoantibodies and their application in research focused on specific disorders have shown that some cytokine autoantibodies play an important role in the pathogenesis of disease. Additionally, levels of cytokine autoantibodies may also correlate with disease severity and progression in certain infectious and autoimmune diseases but not in others. This suggests that cytokine-specific pathogenic differences exist. While multiple lines of evidence support the notion that high avidity cytokine autoantibodies are present and likely to be ubiquitous in healthy individuals, their potential physiological role, if any, is less clear. It is believed that they may function by scavenging pro-inflammatory cytokines and thereby inhibiting deleterious 'endocrine' effects, or by serving as carrier proteins, providing a 'reservoir' of inactive cytokines and thus modulating cytokine bioactivity. A central hypothesis is that sustained or repeated high-level exposure to cytokines triggers defects in T-cell tolerance, resulting in the expansion of existing cytokine autoantibody-producing B cells.

Rituximab is useful in the treatment of Felty's syndrome.

Felty's syndrome is regarded as a severe variant of rheumatoid arthritis (RA) that develops in less than 1% of patients with RA. It consists of a triad of RA, splenomegaly, and leukopenia, which tends to develop after a long course of RA. Treatment of neutropenia is mainly comprised of disease-modifying antirheumatic drugs including methotrexate, hydroxychloroquine, auronofin, penicillamine, glucocorticoids, and granulocyte monocyte colony stimulating factor. Recently, there has been a growing interest in the biologic agent rituximab in the treatment of Felty's syndrome. To our knowledge, only one previous case of rituximab being beneficial in the treatment of Felty's syndrome has been reported. We report the case of a 60-year-old man with Felty's syndrome in whom treatment with rituximab led to a sustained neutrophil response and marked symptomatic improvement in the form of decrease in the size of rheumatoid nodules and better pain control.

Anti-cyclic citrullinated peptide-2 (CCP2) autoantibodies and extra-articular manifestations in Greek patients with rheumatoid arthritis.

The objective of our study was to establish whether there is an association between rheumatoid arthritis with extra-articular manifestations (exRA) and anti-cyclic citrullinated peptide 2 (anti-CCP2) antibodies in Greeks. A retrospective study of 220 Greek patients with RA, 95 with exRA and 125 without extra-articular manifestations (cRA). Serum anti-CCP2 antibodies and IgM rheumatoid factor (RF) were measured. CCP2(+) were 65.3% of exRA and 58.4% of cRA patients. RF(+) were 69.5% of exRA and 60.0% of cRA patients. Among exRA patients, 37.9% had high serum anti-CCP2 antibody levels (>100 IU/ml) compared to 21.6% cRA patients (p = 0.008). Serositis and pulmonary fibrosis were found to be associated with high levels of anti-CCP2 antibodies (52.9 vs 26.6%, p = 0.02 and 63.6 vs 26.8%, p = 0.008, respectively). Serum RF levels were 265.0 +/- 52.0 IU/ml (mean +/- SEM) in exRA and 205.1 +/- 40.6 (mean +/- SEM) in cRA (NS). High serum RF levels (>268 IU/ml) were more likely to have sicca syndrome. In Greek patients with rheumatoid arthritis (RA), high serum anti-CCP2 antibodies are associated with serositis and pulmonary fibrosis. Therefore, anti-CCP2 antibodies have prognostic significance in patients with RA.

Rheumatoid factor and antibodies to cyclic citrullinated peptides are associated with severe extra-articular manifestations in rheumatoid arthritis.

OBJECTIVE: To study antibodies to cyclic citrullinated peptides (anti-CCP) and rheumatoid factor in patients with active, severe extra-articular rheumatoid arthritis (ExRA) compared with controls without ExRA. METHODS: 35 consecutive patients with severe ExRA manifestations according to predefined criteria were studied. 70 patients with rheumatoid arthritis, but no ExRA manifestations, individually matched for age, sex and disease duration, served as controls. Patients were included when ExRA was diagnosed, before any new treatment was started. Anti-CCPs were detected with ELISA, rheumatoid factor was quantified using nephelometry and anti-nuclear antibodies (ANA) were investigated using indirect immune fluorescence. RESULTS: Anti-CCPs were detected in 77% of patients with ExRA versus 56% of controls without ExRA (p = 0.03). Anti-CCP levels also tended to be higher in patients with ExRA (p = 0.09). Rheumatoid factor was detected in 94% v 71% of patients and controls, respectively (p = 0.006), and rheumatoid factor levels were higher in patients with ExRA (median interquartile range (IQR) 245 IU/ml (94-604) v 73 IU/ml (not detected-165); p = 0.001). Levels and occurrence of ANA did not differ between patients with ExRA and controls. Patients with ExRA had higher swollen joint counts and C reactive protein levels, but no correlations were found between anti-CCP or rheumatoid factor levels and these measures within the ExRA group. CONCLUSION: Rheumatoid factor is strongly associated with severe ExRA manifestations in patients with rheumatoid arthritis, and a similar but weaker association exists for anti-CCPs. This suggests a role for rheumatoid factor and anti-CCP in the pathogenesis of ExRA.

Pathogenesis of neutropenia in large granular lymphocyte leukemia and Felty syndrome.

T-cell large granular lymphocyte leukemia (TLGL) is an atypical chronic lymphoproliferative disorder derived from cytotoxic T-cells (CTL). Unlike most forms of leukemia, the pattern of bone marrow infiltration in TLGL may be subtle and the cytopenias are often lineage specific, with neutropenia dominating. Both granulocytic survival and proliferation defects are observed and are mediated by humoral and cell-mediated mechanisms respectively. Splenic production of immune complexes induces a neutrophil survival defect, where as Fas expression by leukemic CTL results in a marrow based proliferation defect. These humoral and cell-mediated pathways induce granulocytic apoptosis through independent intracellular mechanisms which are not mutually exclusive and may be observed concurrently in individual patients with either TLGL or FS. A variety of therapeutic interventions have been utilized in the management of TLGL and Felty syndrome, including methotrexate, cyclosporine A, cyclophosphamide, glucocorticoids, myeloid colony stimulating factors and splenectomy. Their efficacy and mechanisms of action are reviewed.

Felty's syndrome.

Felty's syndrome (FS) comprises a triad of rheumatoid arthritis (RA), neutropenia and splenomegaly, occurring in less than 1% of RA patients. Clinically it is characterized by severe joint destruction contrasting with moderate or absent joint inflammation and severe extra-articular disease, including a high frequency of rheumatoid nodules, lymphadenopathy, hepatopathy, vasculitis, leg ulcers, skin pigmentation etc. Recurrent bacterial infections are mostly due to the severe, otherwise unexplained neutropenia. The cause of neutropenia lies in both decreased granulopoiesis and increased peripheral destruction of granulocytes. Recurrent infections may lead to increased mortality. Spontaneous remission of the syndrome also occurs. Over 95% of FS patients are positive for rheumatoid factor (RF), 47-100% are positive for antinuclear antibody (ANA), and 78% of patients have the HLA-DR4*0401 antigen. Some 30% of FS patients have large granular lymphocyte (LGL) expansion. LGL expansion associated with uncomplicated RA is immunogenetically and phenotypically very similar to but clinically different from FS. Neutropenia of FS can be effectively treated with disease-modifying anti-rheumatic drugs (DMARDs), the widest experience being with methotrexate (MTX). Results of treatment with granulocyte colony-stimulating factor (G-CSF) are encouraging, but there is no experience with other biological agents. Splenectomy results in immediate improvement of neutropenia in 80% of the patients, but the rate of infection decreases to a lesser degree.

Autoantibodies against granulocyte-macrophage colony stimulating factor and interleukin-3 are rare in patients with Felty's syndrome.

OBJECTIVES: Antibodies against granulocyte colony stimulating factor are frequently found in patients with Felty's syndrome (FS). In this study, we examined the prevalence of antibodies against two other granulopoietic cytokines: granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-3 (IL3). METHODS: Sera of 32 patients with FS, 20 normocytic patients with rheumatoid arthritis (RA), and 72 healthy individuals were screened for the presence of antibodies against GM-CSF and IL3 by ELISA and bioassays, using the human erythroleukaemia cell line TF-1. RESULTS: In two of the 32 patients with FS, antibodies to GM-CSF and IL3 were detectable by ELISA. Binding anti-GM-CSF antibodies were also detected in one of the 72 healthy controls, while in another healthy subject and in one of the patients with normocytic RA, anti-IL3 antibodies were present. Serum from one of the two patients with FS who tested positive for anti-IL3 and anti-GM-CSF antibodies by ELISA showed strong neutralising capacity to the biological effect of IL3, but not to GM-CSF in vitro. Patients with FS had significantly higher serum levels of GM-CSF (median; 2.82 pg/mL; interquartile range 2.64-3.19 pg/mL) compared with patients with RA (2.52 pg/mL; 2.28-2.72 pg/mL; p = 0.012) and healthy controls (2.23 pg/mL; 2.04-2.52; p<0.001). In addition, serum levels of IL3 in patients were significantly higher in FS (10.05 pg/mL; 8.94-11.98) compared with controls (4.79 pg/mL; 3.72-7.22; p<0.001), but not compared with RA patients (9.52 pg/mL; 8.32-10.42; p = 0.17). CONCLUSIONS: Antibodies to GM-CSF and IL3 are rare in patients with FS and RA and in healthy subjects. In individual patients with FS, the presence of neutralising anti-IL3 antibodies may contribute to the development of cytopenia.