Use of intravenous gamma globulin for the treatment of autoimmune neutropenia of childhood and autoimmune hemolytic anemia

Anti-Inflammatory and Immunomodulatory Effect of High-Dose Immunoglobulins in Children: From Approved Indications to Off-Label Use

BACKGROUND

The large-scale utilization of immunoglobulins in patients with inborn errors of immunity (IEIs) since 1952 prompted the discovery of their key role at high doses as immunomodulatory and anti-inflammatory therapy, in the treatment of IEI-related immune dysregulation disorders, according to labelled and off-label indications. Recent years have been dominated by a progressive imbalance between the gradual but constant increase in the use of immunoglobulins and their availability, exacerbated by the SARS-CoV-2 pandemic.

OBJECTIVES

To provide pragmatic indications for a need-based application of high-dose immunoglobulins in the pediatric context.

SOURCES

A literature search was performed using PubMed, from inception until 1st August 2023, including the following keywords: anti-inflammatory; children; high dose gammaglobulin; high dose immunoglobulin; immune dysregulation; immunomodulation; immunomodulatory; inflammation; intravenous gammaglobulin; intravenous immunoglobulin; off-label; pediatric; subcutaneous gammaglobulin; subcutaneous immunoglobulin. All article types were considered.

IMPLICATIONS

In the light of the current imbalance between gammaglobulins' demand and availability, this review advocates the urgency of a more conscious utilization of this medical product, giving indications about benefits, risks, cost-effectiveness, and administration routes of high-dose immunoglobulins in children with hematologic, neurologic, and inflammatory immune dysregulation disorders, prompting further research towards a responsible employment of gammaglobulins and improving the therapeutical decisional process.

Evans syndrome: clinical perspectives, biological insights and treatment modalities

Evans syndrome (ES) is a rare and chronic autoimmune disease characterized by autoimmune hemolytic anemia and immune thrombocytopenic purpura with a positive direct anti-human globulin test. It is classified as primary and secondary, with the frequency in patients with autoimmune hemolytic anemia being 37%–73%. It predominates in children, mainly due to primary immunodeficiencies or autoimmune lymphoproliferative syndrome. ES during pregnancy is associated with high fetal morbidity, including severe hemolysis and intracranial bleeding with neurological sequelae and death. The clinical presentation can include fatigue, pallor, jaundice and mucosal bleeding, with remissions and exacerbations during the person’s lifetime, and acute manifestations as catastrophic bleeding and massive hemolysis. Recent molecular theories explaining the physiopathology of ES include deficiencies of CTLA-4, LRBA, TPP2 and a decreased CD4/CD8 ratio. As in other autoimmune cytopenias, there is no established evidence-based treatment and steroids are the first-line therapy, with intravenous immunoglobulin administered as a life-saving resource in cases of severe immune thrombocytopenic purpura manifestations. Second-line treatment for refractory ES includes rituximab, mofetil mycophenolate, cyclosporine, vincristine, azathioprine, sirolimus and thrombopoietin receptor agonists. In cases unresponsive to immunosuppressive agents, hematopoietic stem cell transplantation has been successful, although it is necessary to consider its potential serious adverse effects. In conclusion, ES is a disease with a heterogeneous course that remains challenging to patients and physicians, with prospective clinical trials needed to explore potential targeted therapy to achieve an improved long-term response or even a cure.

Plasmapheresis in a child with cold antibody autoimmune hemolytic anemia: case report

Autoimmune hemolytic anemia is a picture of hemolysis which is caused by autoantibodies against red blood cell surface antigens. It is classified as primary, secondary or warm and cold autoimmune hemolytic anemia according to the temperature at which antibodies react. It is usually an acute and self-limiting condition. Here, we present a three-year-old male patient who presented with malaise, paleness, and dark-colored urine. His hemoglobin level was 5.8 g/dL, and increased indirect bilirubin and lactate dehydrogenase levels and decreased haptoglobulin and reticulocyte levels were noted. A direct Coombs test was positive using anti-C3. Four erythrocyte suspension transfusions were given because the anemia was life-threatening. High-dose steroids (30 mg/kg/ day, methylprednisolone) and intravenous immunoglobulin (1 g/kg/day, two days) treatments were unresponsive. Plasmapheresis was performed and no further transfusions were needed after plasmapheresis. Plasmapheresis treatment can be effective in children with cold type autoimmune hemolytic anemia.

Update on the use of immunoglobulin in human disease: A review of evidence

Human immunoglobulin preparations for intravenous or subcutaneous administration are the cornerstone of treatment in patients with primary immunodeficiency diseases affecting the humoral immune system. Intravenous preparations have a number of important uses in the treatment of other diseases in humans as well, some for which acceptable treatment alternatives do not exist. We provide an update of the evidence-based guideline on immunoglobulin therapy, last published in 2006. Given the potential risks and inherent scarcity of human immunoglobulin, careful consideration of its indications and administration is warranted.

Experience with Evans syndrome in an academic referral center

Objective

To document the experience of one referral service with patients diagnosed with Evans syndrome, the treatment and response and to briefly review current treatment strategies and results.

Methods

Patients enrolled in this study fulfilled criteria for Evans syndrome. Data were retrieved from the clinical files and electronic databases of the Department of Hematology, Hospital Universitario “Dr. José Eleuterio González”. Treatment modalities and response and the use of additional therapies were evaluated. The literature was reviewed in the context of the clinical course of the studied patients.

Results

Six patients were diagnosed with Evans syndrome in the study period. Patient 1 was treated with steroids, relapsed twice and was again treated with steroids. Patient 2 treated initially with steroids plus intravenous immunoglobulin was subsequently lost to follow-up. A good response was achieved in Patients 3 and 4, who were treated with steroids plus rituximab; patient 4 also received danazol as a second-line therapy. However both relapsed and subsequently underwent splenectomy at ten and nine months, respectively. One patient, number 5, treated with steroids, danazol and rituximab did not relapse within four years of follow-up and Patient 6, who received steroids plus danazol did not relapse within three years of follow-up.

Conclusion

Evans syndrome is an uncommon hematologic condition rarely diagnosed and not widely studied. Clinicians must have it in mind when evaluating a patient with a positive direct antiglobulin test, anemia and thrombocytopenia, since prognosis depends on its early recognition and opportune therapy, but even this leads to variable results.

Clinical applications of immunoglobulin: update

Human immunoglobulin is the most used blood product in the clinical practice. Immunoglobulin applications have increased quickly since the elucidation of its immunomodulatory and antiinflammatory properties which turned this blood product into a precious tool in the treatment of numerous diseases that present with humoral immune deficiency or that cause immune system dysfunction. Currently, the approved indications for Ig are: primary immunodeficiencies, secondary immunodeficiencies (multiple myeloma or chronic lymphoid leukemia), Kawasaki syndrome, immune thrombocytopenic purpura, Guillain Barré syndrome, graft-versus-host disease following bone marrow transplantation and repeat infections in HIV children. On the other hand, there are numerous "off-label" indications of immunoglobulin, which represent 20-60% of all clinical applications of this drug. It is important to study all these indications and, above all, the scientific evidence for its use, in order to provide patients with a new therapeutic option without burdening the health system. This review results from a wide selection of papers identified in the Pubmed and Lilacs scientific electronic databases. A group of descriptors were used from human immunoglobulin to the names of each disease that immunoglobulin is clinically applied. Our main objective is to list the numerous indications of immunoglobulin, both authorized and "off-label" and to analyze these indications in the light of the most recent scientific evidence.

Evidence for the use of intravenous immunoglobulins--a review of the literature

Intravenous immunoglobulins (IVIg) were first introduced in the middle of the twentieth century for the treatment of primary immunodeficiencies. In 1981, Paul Imbach noticed an improvement of immune-mediated thrombocytopenia, in patients receiving IVIg for immunodeficiencies. This opened a new era for the treatment of autoimmune conditions with IVIg. Since then, IVIg has become an important treatment option in a wide spectrum of diseases, including autoimmune and acute inflammatory conditions, most of them off-label (not included in the US Food and Drug Administration recommendation). A panel of immunologists and internists with experience in IVIg therapy reviewed the medical literature for published data concerning treatment with IVIg. The quality of evidence was assessed, and a summary of the available relevant literature in each disease was given. To our knowledge, this is the first all-inclusive comprehensive review, developed to assist the clinician when considering the use of IVIg in autoimmune diseases, immune deficiencies, and other conditions.

IVIg selectively and rapidly decreases circulating pathogenic autoantibodies in pemphigus vulgaris

BACKGROUND

Intraveneous immunoglobulin (IVIg) is increasingly used to treat pemphigus vulgaris (PV). The mechanism by which it does so is not known. The following study was conducted to confirm the effectiveness of IVIg for the acute control of active PV and to elucidate the mechanism by which it does.

METHODS

Twelve patients with active and severe PV unresponsive to conventional therapy with high doses of systemic steroids together with or without a cytotoxic drug were treated with a single dose of IVIg (400 mg/kg/day for 5 days). All patients were concurrently given cyclophosphamide or azathioprine of not already on one of these two drugs. The primary end-points were healing of skin lesions, changes in serum levels of intercelular (IC) autoantibodies and in steroid doses one to 3 weeks after initiation of IVIg.

RESULTS

Within 1 week of initiating IVIg the activity of PV was controlled in most cases. Within 3 weeks the average baseline dose of systemic steroid was reduced by 40%. Serum levels of IC antibodies rapidly declined by an average of 59% within 1 week of initiating IVIg and by 70% within 2 weeks. The decrease was selective, as the average serum levels of antibody to varicella-herpes zoster did not decrease in the 4 patients in whom they were measured. The decrease in IC antibodies was inversely related to serum levels of total inmmunoglobulin (IgG). The decrease in IC antibodies was not due to blocking factors in the IVIg preparation and was too rapid to be due to suppression of IgG synthesis, suggesting that it resulted from increased catabolism.

CONCLUSIONS

IVIg can rapidly control active PV unresponsive to conventional therapy by causing a selective and very rapid decline in the autoantibodies that mediate the disease. We believe it does so by increasing the catabolism of all serum IgG antibodies, and that this results in a selective decrease in only abnormal autoantibodies as catabolized normal anti bodies are replaced by those present in the IVIg preparation. IVIg is the first treatment that achieves the ideal therapeutic goal in auto-antibody diseases, the selective removal of the pathogenic antibodies without affecting the level of normal antibodies.

Modulation of dendritic cell development by immunoglobulin G in control subjects and multiple sclerosis patients

Intravenous immunoglobulin (IVIg) preparations are reportedly effective in inhibiting the relapse of multiple sclerosis (MS), but few reports have investigated the effect of IVIg on dendritic cells (DCs), which are thought to be involved in such relapses. In the system that uses monokines to differentiate DCs from peripheral blood monocytes (Mo-DCs), we investigated the effect of immunoglobulin G (IgG) on these antigen-presenting cells. Using monocytes derived from healthy volunteers, IgG partially inhibited the expression of CD1a, a marker of immature DCs (imDCs), and CD40 and CD80, which are markers associated with T cell activation. In contrast, IgG enhanced the expression of CD83, a marker of mature DCs (mDCs). Furthermore, IgG markedly inhibited the expression of CD49d [very late activation antigen (VLA)-4 alpha4-integrin], the adhesion molecule required for mDCs to cross the blood-brain barrier. We obtained similar results on all the aforementioned cell surface molecules investigated in both healthy controls and MS patients. In addition, IgG treatment of cells from both healthy controls and MS patients inhibited the production of interleukin (IL)-12, a cytokine associated with mDC differentiation, but did not inhibit the production of IL-10. These results suggested the possibility that IgG treatment, apart from its known ability to regulate inflammation, may help to prevent relapses of MS by controlling DC maturation, consequently inhibiting invasion of immune cells into the central nervous system and affecting the cytokine profile.

Guidelines on the Use of Intravenous Immune Globulin for Hematologic Conditions

Canada's per capita use of intravenous immune globulin (IVIG) grew by approximately 115% between 1998 and 2006, making Canada one of the world's highest per capita users of IVIG. It is believed that most of this growth is attributable to off-label usage. To help ensure IVIG use is in keeping with an evidence-based approach to the practice of medicine, the National Advisory Committee on Blood and Blood Products of Canada (NAC) and Canadian Blood Services convened a panel of national experts to develop an evidence-based practice guideline on the use of IVIG for hematologic conditions. The mandate of the expert panel was to review evidence regarding use of IVIG for 18 hematologic conditions and formulate recommendations on IVIG use for each. A panel of 13 clinical experts and 1 expert in practice guideline development met to review the evidence and reach consensus on the recommendations for the use of IVIG. The primary sources used by the panel were 3 recent evidence-based reviews. Recommendations were based on interpretation of the available evidence and where evidence was lacking, consensus of expert clinical opinion. A draft of the practice guideline was circulated to hematologists in Canada for feedback. The results of this process were reviewed by the expert panel, and modifications to the draft guideline were made where appropriate. This practice guideline will provide the NAC with a basis for making recommendations to provincial and territorial health ministries regarding IVIG use management. Specific recommendations for routine use of IVIG were made for 7 conditions including acquired red cell aplasia; acquired hypogammaglobulinemia (secondary to malignancy); fetal-neonatal alloimmune thrombocytopenia; hemolytic disease of the newborn; HIV-associated thrombocytopenia; idiopathic thrombocytopenic purpura; and posttransfusion purpura. Intravenous immune globulin was not recommended for use, except under certain life-threatening circumstances, for 8 conditions including acquired hemophilia; acquired von Willebrand disease; autoimmune hemolytic anemia; autoimmune neutropenia; hemolytic transfusion reaction; hemolytic transfusion reaction associated with sickle cell disease; hemolytic uremic syndrome/thrombotic thrombocytopenic purpura; and viral-associated hemophagocytic syndrome. Intravenous immune globulin was not recommended for 2 conditions (aplastic anemia and hematopoietic stem cell transplantation) and was contraindicated for 1 condition (heparin-induced thrombocytopenia). For most hematologic conditions reviewed by the expert panel, routine use of IVIG was not recommended. Development and dissemination of evidence-based guidelines may help to facilitate appropriate use of IVIG.

Management of Evans syndrome

Evans syndrome is an uncommon condition defined by the combination (either simultaneously or sequentially) of immune thrombocytopenia (ITP) and autoimmune haemolytic anaemia (AIHA) with a positive direct antiglobulin test (DAT) in the absence of known underlying aetiology. This condition generally runs a chronic course and is characterised by frequent exacerbations and remissions. First-line therapy is usually corticosteroids and/or intravenous immunoglobulin, to which most patients respond; however, relapse is frequent. Options for second-line therapy include immunosuppressive drugs, especially ciclosporin or mycophenolate mofetil; vincristine; danazol or a combination of these agents. More recently a small number of patients have been treated with rituximab, which induces remission in the majority although such responses are often sustained for <12 months and the long-term effects in children are unclear. Splenectomy may also be considered although long-term remissions are less frequent than in uncomplicated ITP. For very severe and refractory cases stem cell transplantation (SCT) offers the only chance of long-term cure. The limited data available suggest that allogeneic SCT may be superior to autologous SCT but both carry risks of severe morbidity and of transplant-related mortality. Cure following reduced-intensity conditioning has now been reported and should be considered for younger patients in the context of controlled clinical trials.

Immunomodulatory Effects of Intravenous Immunoglobulins as a Treatment for Autoimmune Diseases, Cancer, and Recurrent Pregnancy Loss

Intravenous immunoglobulin (IVIG) is a safe preparation, made of human plasma of thousands of healthy donors. The fascinating history of gamma globulin therapy begins in 1930 when Finland treated pneumococcal pneumonia patients with equine serum, which prolonged their survival from pneumonia. Since then, significant breakthroughs were achieved by Cohn, Bruton, Imbach, and others, whose clinical contribution to the world of medicine was of great importance. Originally IVIG was used to treat immunodeficiencies. Later on the use of IVIG extended to autoimmune diseases as well. The efficacy of IVIG has been established only in several autoimmune diseases; clinical reports of trials, series, and case reports indicate significant improvement in many more autoimmune diseases. IVIG have also showed antimetastatic effects in a variety of cancer cell lines, as well as in a few case reports. The efficiency of IVIG has also been observed in recurrent pregnancy loss (RPL), either as a result of an autoimmune disease or spontaneous. Several attempts were made to discover the immunomodulatory effects of IVIG, but it is still not fully understood. Clearly IVIG has multiple mechanisms of actions, which are thought to cooperate synergistically. One of the main mechanisms of actions of IVIG is its ability to neutralize pathogenic autoantibodies via anti-idiotypic antibodies within IVIG preparation. The ability of IVIG to neutralize pathogenic autoantibodies is of great importance in many autoimmune diseases, as well as in RPL. In cancer cell lines, IVIG modulates the immune system in a few ways, including the induction of IL-12 secretion, which consequently activates natural killer cells, and the induction of expression of proapoptotic genes only in cancer cells. Side effects from IVIG are rare and mostly mild and transient. More importantly adverse effects can be minimized by administration to a selective patient population in a proper way: slow infusion rate of 0.4 g/Kg body weight IVIG for 5 consecutive days, given in monthly cycles. The only downside of IVIG therapy is its high price. Therefore, clinicians should balance efficiency versus cost in deciding whether or not to treat certain conditions with IVIG.

Effets immunomodulateurs des immunoglobulines intraveineuses

Intravenous immunoglobulins (IVIg) are therapeutic preparations of normal human IgG obtained from pools of more than 1000 healthy blood donors. They are currently used in the treatment of a wide range of auto-immune diseases, whether associated with auto-antibodies or auto-reactive T lymphocytes, as well as in the treatment of systemic inflammatory diseases. Several mechanisms of action have been identified during the last 20 years, including: (i) modulation of Fc receptors expression on leukocytes and endothelial cells; (ii) interaction with complement proteins; (iii) modulation of cytokines and chemokines synthesis and release; (iv) modulation of cell proliferation and apoptosis; (v) remyelinisation; (vi) neutralisation of circulating autoantibodies; (vii) selection of repertoires of B and T lymphocytes; (viii) interaction with other cell-surface molecules on lymphocytes and monocytes; (ix) corticosteroid sparing. These mechanisms of action are multiple and often intricate. However, they are still little known and further investigations are warranted.

Neutrophil disorders and their management

Neutrophil disorders are an uncommon yet important cause of morbidity and mortality in infants and children. This article is an overview of these conditions, with emphasis on clinical recognition, rational investigation, and treatment. A comprehensive list of references is provided for further reading.

A practical approach to evaluating and treating neutropenia in the neonatal intensive care unit

Neutropenia is a relatively common problem in the NICU, recognized in as many as 8% of patients at some time during their hospital stay. In most instances, neutropenia among NICU patients is of short duration and has little influence on outcome. In other cases it is prolonged and severe, and constitutes a serious antimicrobial defense deficiency. When a neonatologist discovers a low blood neutrophil count, choices must be made regarding further evaluation and treatment. The authors hope that the information provided in this article is useful in making these choices.

Human intravenous immunoglobulin therapy

Human intravenous immunoglobulin (hIVIG) is a preparation of normal polyspecific IgG obtained from the plasma of healthy blood donors. Although purified immunoglobulins were initially developed for treatment of primary immunodeficiency syndromes, they have since been documented to be effective in the treatment of some immune-mediated diseases such as immune-mediated thrombocytopenia purpura and autoimmune hemolytic anemia. Blockade of Fc receptors on mononuclear phagocytic cells has been proposed as the most likely mechanism for the rapid early response to hIVIG treatment. Human IVIG has been used to treat canine immune-mediated hemolytic anemia (IMHA), anemia with myelofibrosis, and immune-mediated thrombocytopenia. Doses from 0.5 to 1.5 g/kg may be effective, although most studies have used a dose of 1 g/kg. Human IVIG is administered as an intravenous infusion over 6 to 12 hours, and dogs should be carefully monitored for adverse reactions during administration. The possibility of a increased risk of thromboembolism should be considered when undertaking hIVIG treatment. The safety of multiple treatments of hIVIG has not been established. In most dogs with IMHA, benefit may be limited to short-term improvement in hematocrit, which may allow time for other treatment modalities to become effective. Dogs with nonregenerative anemia and associated myelofibrosis may have longer-term responses to hIVIG treatment.

New therapeutic avenues in autoimmunity

During the last decade, much progress has been made in the understanding of processes that lead to autoimmunity. Cellular interactions mediated through cytokines and adhesion molecules were found to play a major role in the genesis of autoimmune conditions. During this period, we learned to recruit monoclonal antibodies to manipulate these delicate processes and to divert their outcome to a path we control better. Our comprehension of IVIG (intravenous immunoglobulin therapy) has broadened, and new indications for the implementation of this promising therapy have been pursued. In this review, we shed light on new therapeutic modalities that have been published since our previous report and discuss new data concerning the old modalities.

Diagnosis and management of chronic neutropenia during childhood

The approach to the diagnostic evaluation of a patient with neutropenia can be guided largely by clinical history and physical examination and does not always require an extensive laboratory evaluation. Based on the history and bone marrow morphology, most children with chronic neutropenia can be classified and managed. Most patients with chronic neutropenia are free of infections and are able to maintain a normal lifestyle with no or minimal medical intervention. On the other hand, for patients with recurrent or severe infections, careful follow-up and institution of treatment are mandatory. The Food and Drug Administration has approved the use of rhG-CSF in patients with chronic neutropenia. As mentioned previously, the use of colony-stimulating factors has dramatically improved the outcome for many patients with the more severe neutropenia; however, this cytokine is expensive, so treatment should be reserved for more severely affected patients and not given just because the ANC is low. Although concerns exist regarding leukemogenic effects or eventual loss of the progenitor cell compartment driven by the continuous stimulation of rhG-CSF, at this moment, the long-term data available suggest that the chronic administration of rhG-CSF is safe.

Autoimmune neutropenia successfully treated with cyclosporine

A case history is presented concerning a 59-year-old female patient with chronic autoimmune neutropenia complicated by recurrent skin infections, mucositis, and conjunctivitis. For subjective reasons she refused treatment with prednisone, but eventually cyclosporine led to an important clinical improvement and an increase of the peripheral granulocyte count. Treatment modalities of autoimmune neutropenia are briefly discussed.

Anti-idiotypic activity against anti-myeloperoxidase antibodies in pooled human immunoglobulin

We investigated the ability of six different pooled human immunoglobulin (PHIG) preparations to inhibit the binding of anti-myeloperoxidase (MPO) antibodies to MPO. All six PHIG preparations inhibited the binding of anti-MPO antibodies from six sera to MPO in a concentration-dependent manner in the concentration range 0.016-10 mg/ml. There was considerable variation in the ability of each PHIG preparation to inhibit the binding of anti-MPO antibody in a given serum. Further differences were seen in the ability of a given PHIG to inhibit anti-MPO binding in different sera. F(ab')2 fragments from two PHIG preparations also inhibited in a concentration-dependent manner anti-MPO binding to MPO in all six sera in the concentration range 0.002-2.65 mg/ml, with a maximum inhibition of 42%. Little inhibition was seen with F(ab')2 of normal human IgG from individual donors (1.8-12.2% at the maximum concentration of 2 mg/ml). F(ab')2 fragments from three anti-MPO containing sera and two affinity-purified anti-MPO antibodies were eluted by affinity chromatography from Sepharose-bound PHIG F(ab')2 and showed anti-MPO antibody activity. We have shown that PHIG and F(ab')2 fragments of PHIG inhibit anti-MPO binding to MPO, and further that F(ab')2 fragments of PHIG bind to F(ab')2 fragments of anti-MPO antibodies. These observations indicate binding between the variable regions of PHIG and the antigen binding site of anti-MPO antibodies, and are consistent with an anti-idiotypic reaction. The variability seen in the inhibitory effect of the different PHIG preparations in anti-MPO-positive sera implies differences in their anti-idiotype content, while the variability of the inhibitory effect of a particular PHIG preparation between different sera suggests heterogeneity in the idiotypic repertoire of anti-MPO antibodies. Such variations in the inhibitory effect of different PHIG preparations on antibody binding may be an important determinant of their therapeutic effect.

High-dose immunoglobulin therapy as an immunomodulatory treatment of rheumatoid arthritis

OBJECTIVE

To investigate the efficacy of high-dose intravenous immunoglobulin (IVIg) in the treatment of refractory rheumatoid arthritis (RA).

METHODS

Ten patients with active, severe RA that was unresponsive to first- and second-line agents were administered IVIg monthly, for 6 months.

RESULTS

Following IVIg treatment, there was significant improvement in both subjective and objective parameters of disease activity in all 9 patients who completed the protocol. This improvement was noted to occur as early as after the second infusion of IVIg. After discontinuation of the treatment, all patients had a relapse of the disease within a few weeks.

CONCLUSION

Since the reduction in clinical activity paralleled a decrease in the CD4+CDw29+:CD4+CD45RA+ cell ratio, some of the therapeutic benefits associated with IVIg may be due to a direct influence on the CD4+CD45RA+ subset. Although the possibility of carrying out further controlled studies on a larger scale is limited by the high cost of the treatment, IVIg appears to be an effective therapy for refractory RA.

Autoimmune neutropenia of infancy

AIM

Assessment of the clinical and haematological course of autoimmune neutropenia of infancy (ANI) in a defined childhood population in the south east of Scotland.

METHODS

From January 1986 to February 1991 all children presenting with persistent neutropenia were examined serologically for evidence of antigranulocyte antibodies. The clinical course of those children found to have anti-granulocyte antibodies was then closely monitored.

RESULTS

During the study period five children had serologically confirmed ANI, giving an annual incidence of approximately 1/100,000 in this population. All of these cases followed the classic benign course of the condition. The presenting illnesses were mild, often with superficial skin sepsis and the initial absolute neutrophil count (ANC) ranged from 0.00-0.87 x 10(9)/l. All have remained well with no serious infections. Two children attained a normal ANC after 14 and 24 months respectively, the others currently remain neutropenic.

CONCLUSIONS

Autoimmune neutropenia of infancy is a condition which rests on a serological diagnosis. It follows a chronic benign course and all children eventually attain a normal ANC. The level of antigranulocyte antibody in the serum often begins to wane prior to improvement in the ANC and can give an indication of when recovery will begin to occur.

IVIG in the treatment of children with acute and chronic idiopathic thrombocytopenic purpura and the autoimmune cytopenias

IVIG has been shown to be useful in the treatment of acute and chronic ITP, immune neutropenia, and in some cases of AIHA. The mechanism of action of IVIG is owing to a number of factors, which include Fc blockade, immune modulation of T- and B-cell number and function, alterations in NK activity, and direct effects on autoantibody binding and production via the antiidiotypic antibody network. Current research efforts are directed toward elucidation of these modalities and determination of their relative importance in treating patients with immune-mediated cytopenias.

Intravenous immunoglobulins (IVIg) in the treatment of autoimmune diseases

Intravenous immunoglobulin (IVIg) therapy is increasingly used in autoimmune diseases. Although its efficacy has only been established in a few specific antibody-mediated autoimmune conditions, accumulating evidence on the regulatory role of circulating immunoglobulins in the selection of peripheral B cell repertoires makes it an attractive potential therapeutic option to clinical immunologists. This overview briefly discusses the current use of IVIg in human autoimmune diseases with a particular emphasis on the possible mechanisms by which IVIg could suppress pathological autoimmune responses.

Mechanisms of action of intravenous immunoglobulin therapy and potential use in autoimmune connective tissue diseases

It has been almost 10 years since the observations on the efficacy of intravenous immunoglobulin (IVIG) in patients with autoimmune thrombocytopenic purpura. Over the next decade, IVIG was used in other types of autoimmune diseases. Much work has also been done on gaining a better understanding of the mechanism(s) by which IVIG exerts its effects in these autoimmune diseases. This review examines the proposed mechanisms of action of IVIG and establishes a rationale for the use of this type of therapy in systemic lupus erythematosus (SLE) and other autoimmune connective tissue disorders. Currently, only anecdotal reports are available on the treatment of SLE with IVIG. Nevertheless, studies thus far suggest that IVIG may be useful in selected SLE patients with cytopenias and cutaneous vasculitis and may have a steroid-sparing effect in patients with SLE and juvenile rheumatoid arthritis. In SLE patients with renal disease, it should be used cautiously because some patients have worsening of their renal function with IVIG infusions. These preliminary experiences suggest that multicenter controlled trials on the therapeutic use of IVIG in SLE and other connective tissue disorders would be important.

Intravenous immunoglobulin (IVIG) for the therapy of autoimmune disorders

The weight of evidence from numerous clinical studies supports the use of IVIG, particularly at higher doses, in the treatment of a wide range of autoimmune disorders. Extensive experience has documented the safety of IVIG therapy but its present relatively high cost necessitates firmly establishing its efficacy. There is an acute need to define those disease states where IVIG is indicated and effective. Large-scale, possibly multicentered, clinical trials employing rigorous controls will resolve these questions. Concurrent fundamental immunologic studies will elucidate the mechanisms underlying the clinical effects. We are experiencing an exciting new era of effective immunotherapies and intravenous gamma-globulin preparations have already secured an important place in the therapeutic armamentarium. While one must guard against unsubstantiated applications, critical exploration of new uses for this unique product is warranted.

High dose intravenous gammaglobulins in autoimmune disorders: mode of action and therapeutic uses

Gammaglobulins administered intramuscularly have been used for more than 40 years to treat antibody deficiency states. In the last decade intravenous preparations were developed. They do not aggregate and contain IgG molecules with intact recognition and effector functions. These compounds are safe and only minor side effects were reported even when high doses were given. While studying their effect when given in high doses to hypogammaglobulinemic patients, an accidental finding was observed regarding their beneficial effect in idiopathic thrombocytopenic purpura (ITP). This observation led to many studies looking at the effect of high dose gammaglobulin in several other autoimmune diseases. While the effect in acute ITP is well established, there are encouraging reports in respect to the effect of intravenous gammaglobulin in many other disorders, but no final conclusion can be drawn due to the small numbers of cases studied. The mechanism by which intravenous gammaglobulin exerts its function is still unclear. It may work through the Fc receptor in the reticuloendothelial system, as an immunoregulator agent or interact in the idiotype-antiidiotype network. Intravenous gammaglobulin seems to be an important therapeutic tool in a large number of autoimmune disorders of various etiologies.