IgG anti-IgA subclasses in common variable immunodeficiency and association with severe adverse reactions to intravenous immunoglobulin therapy

Non-allergic Hypersensitivity Reactions to Immunoglobulin Preparations in Antibody Deficiencies: What Role for Anti-IgA IgG and Complement Activation?

The presence of IgG anti-IgA in the serum of primary immunodeficiency (PID) patients has long been considered responsible for hypersensitivity (HS) to immunoglobulin preparations (IgPs), but this link is increasingly being questioned. The aim of this work was to describe the prevalence of IgG anti-IgA and its association with HS, and to explore a new pathophysiological hypothesis involving the complement system. We measured IgG anti-IgA, using a standardised commercial technique, in controls and PID patients, and compared our results to a systematic literature review. We measured complement activation in PID patients before and after IgP infusion, and in vitro after incubation of IgP with serum from controls and PID patients. IgG anti-IgA was detected in 6% (n = 2/32) of PID patients, 30% (n = 3/10) of selective IgA deficiency patients and 2% (n = 1/46) of healthy controls. In the literature and our study, 38 PID patients had IgG anti-IgA and HS to IgPs and 9 had IgG anti-IgA but good tolerance to IgPs. In our patients, we observed a constant complement activation after IgP infusion compared to baseline. In vitro, IgP induced significant complement activation with all sera from tested individuals. IgA immunisation is not rare in PID, higher in selective IgA deficiency, but may also occur in healthy controls. Our results question the clinical relevance and pathophysiological implication of IgG anti-IgA in the context of HS with IgPs. Complement activation-related pseudoallergy could explain the clinical characteristics and natural history of HS symptoms.

Successful Emergency Management of a Dog with Ventilator-Dependent Acquired Myasthenia Gravis with Immunoadsorption

A one-year-old, female intact Samoyed, 12.5 kg, was presented with coughing for 2 weeks, progressive appendicular and axial muscle weakness, megaesophagus and labored breathing for 5 days. There was no improvement with standard treatment. Acquired myasthenia gravis was suspected and the dog was referred with increasing dyspnea. At presentation, the dog showed a severely reduced general condition, was non-ambulatory and showed abdominal and severely labored breathing. A marked hypercapnia (PvCO2 = 90.1 mmHg) was present in venous blood gas analysis. The serum anti-acetylcholine receptor antibody test was consistent with acquired myasthenia gravis (2.1 nmol/L). The dog was anesthetized with propofol and mechanically ventilated with a Hamilton C1 ventilator. Immunoadsorption was performed with the COM.TEC® and ADAsorb® platforms and a LIGASORB® adsorber to eliminate anti-acetylcholine receptor antibodies. Local anticoagulation was performed with citrate. Treatment time for immunoadsorption was 1.5 h with a blood flow of 50 mL/min. A total plasma volume of 1.2 L was processed. Further medical treatment included intravenous fluid therapy, maropitant, esomeprazole, antibiotic therapy for aspiration pneumonia and neostigmine 0.04 mg/kg intramuscularly every 6 h for treatment of acquired myasthenia gravis. Mechanical ventilation was stopped after 12 h. A percutaneous gastric feeding tube was inserted under endoscopic control on day 2 for further medical treatment and nutrition. A second treatment with immunoadsorption was performed on day 3. Again, a total plasma volume of 1.2 L was processed. Immediately after this procedure, the dog regained muscle strength and was able to stand and to walk. After 6 days, the dog was discharged from the hospital. This is the first report of immunoadsorption for emergency management of a dog with acute-fulminant acquired myasthenia gravis. Immunoadsorption may be an additional option for emergency treatment in dogs with severe signs of acquired myasthenia gravis.

Case Report: Cotard's Syndrome in Anti-N-methyl D-aspartate (NMDA) Receptor (Anti-NMDAR) Encephalitis

Cotard's syndrome is uncommon psychopathology among patients with psychotic illnesses. Limited cases had been reported regarding the occurrence of this syndrome in anti-NMDAR encephalitis which itself is a relatively new disease that often presents with florid psychotic symptoms. This poses difficulties in differentiating it from a primary psychiatric illness. Late recognition of anti-NMDAR encephalitis can lead to death as it can progress to autonomic instability in its natural course of illness. We report a patient who first presented with psychotic symptoms with initial negative findings from baseline investigations. Further investigation revealed anti NMDAR antibodies in the cerebrospinal fluid. Prompt treatment was initiated and despite early poor response to the first-line treatment with the development of allergic reaction, our patient recovered completely after 1 month of hospitalization. This case report aims to highlight the importance of early detection of anti-NMDAR encephalitis and the possibility of uncommon psychopathology such as Cotard's syndrome occurring in this disease.

Use of Human Intravenous Immunoglobulin in Veterinary Clinical Practice

Therapy with human intravenous immunoglobulin (hIVIG) as an immunomodulator in veterinary patients results in effective but transient immunosuppression, and may be viable as part of a multidrug strategy against immune-mediated thrombocytopenia and autoimmune cutaneous disease. Efficacy of hIVIG against other veterinary autoimmune diseases is questionable. Veterinary patients tolerate hIVIG therapy well, with few infusion reactions documented. Veterinary clinical trials of hIVIG are limited, and more work is needed to determine the true efficacy and risk of hIVIG administration in companion animals.

Immunoglobulin A deficiency in children, an undervalued clinical issue

Immunoglobulin A (IgA) is the principal antibody in secretions that bathe the gastrointestinal and respiratory mucosal surfaces and acts as an important first line of defense against invasion of pathogenic micro-organisms. The reported prevalence rate of complete IgA deficiency in healthy children ranges from 1:170 to 1:400, and as a solitary condition, it is often considered of limited clinical importance. However, patients with IgA deficiency can develop recurrent respiratory and gastrointestinal infections, as well as allergic and autoimmune diseases. In children referred for recurrent respiratory tract infections, the observed prevalence rate increases more than tenfold. This review discusses several aspects of IgA deficiency in children, including immunologic and microbiome changes in early childhood and the potential consequences of this condition in later life. It illustrates the importance of early identification of children with impaired IgA production who deserve appropriate clinical care and follow-up.

High-dose intravenous immunoglobulins for the treatment of dermatological autoimmune diseases

Based on their immunomodulatory properties, high-dose intravenous immunoglobulins (IVIGs) are successfully used in the treatment of various dermatological autoimmune diseases, in particular pemphigus vulgaris and dermatomyositis. In autoimmune bullous diseases, IVIGs can be used in an adjuvant setting (second- or third-line therapy) once combined immunosuppressive regimens have failed. In dermatomyositis, IVIGs may already be employed as an adjuvant second-line therapy after failure of corticosteroid monotherapy. In scleromyxedema, IVIGs may be considered as first-line treatment, given the lack of effective and safe alternatives. Other potential indications for IVIGs may include severe recalcitrant cases of systemic vasculitis and systemic lupus erythematosus. Toxic epidermal necrolysis may be an indication for high-dose IVIGs if administered early. Common, readily manageable side effects include nausea, headache, fatigue, and febrile infusion reactions. Severe adverse events such as thromboembolic events, anaphylaxis, and acute renal failure are very uncommon. The risk of viral transmission is very low. Potential mechanisms of action include upregulation of inhibitory Fc receptors, reduction of the half-life of endogenous immunoglobulins due to displacement from protective receptor sites, neutralization of autoantibodies by anti-idiotypic antibodies, as well as inhibition of complement activation.

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.

Anaphylaxis to IVIG

Anaphylactic reactions are a known complication in some IgA-deficient patients receiving blood or plasma transfusions. It is of particular interest that anaphylaxis has been observed in patients with common variable immunodeficiency (CVID) who are receiving intravenous gammaglobulin (IVIG), and in that, although these patients have an impaired response to common vaccines, they retain the ability to produce autoantibodies. In this study, we review IgA antibodies (both IgG- and IgE-mediated reactions) in patients with CVID and hypogammaglobulinemia, anaphylaxis in antibody immunodeficient patients receiving IVIG, and proposed mechanisms of desensitization and prevention of anaphylactic reactions in immunodeficient patients receiving IVIG. We summarize and assess the 23 case reports documented in the literature that have described anaphylactic reactions in immunodeficient patients receiving IVIG since 1962 until currently, and make a comparison of their immunoglobulin levels, IgG anti-IgA, IgE anti-IgA, concentration of IVIG, IgA content in IVIG, method used to detect antibodies, length of treatment, and any subsequent tolerated treatment documented.

Anaphylaxis to IGIV in immunoglobulin-naïve common variable immunodeficiency patient in the absence of IgG anti-IgA antibodies: successful administration of low IgA-containing immunoglobulin

Although severe reactions to immunoglobulin preparations have been frequently reported, IgE antibodies against IgA are usually not investigated; and occur predominantly in previously sensitized patients. The purpose is to report anaphylaxis to IGIV during initial infusion in a patient with common variable immunodeficiency with absent IgA without prior sensitization and in the absence of detectable IgG anti-IgA antibodies, and positive skin tests for immediate hypersensitivity to four different preparations of IGIV, one subcutaneous immunoglobulin preparation, and to purified IgA. Patient was treated without side effects with IGIV preparation depleted of IgA to which immediate hypersensitivity skin test was negative.

This case demonstrates that patients with CVID with no IgA and without prior exposure to immunoglobulin or plasma may develop anaphylaxis following initial infusion of IGIV, which appears to be due to IgE anti-IgA, and independent of IgG anti-IgA antibodies. Since there is no good correlation between anaphylaxis/anaphylactic reactions and IgG anti-IgA antibodies, and IgE anti-IgA antibody test is commercially unavailable, we suggest that the patients with CVID with absence of IgA might be skin tested for immediate hypersensitivity prior to initiation of immunoglobulin administration. However, such recommendation may require studies on a large number of patients with CVID with no detectable IgA.

Managing patients with side effects and adverse events to immunoglobulin therapy

Immunoglobulin therapy has not only served as a lifesaving approach for the prevention and treatment of infections in primary and secondary immunodeficiency diseases, but has also been used as an immunomodulatory agent for autoimmune and inflammatory disorders and to provide passive immunity for some infectious diseases. Most of the adverse effects associated with immunoglobulin therapy are mild, transient and self-limiting. However, serious side effects also occur. Therefore, to minimize the adverse events of immunoglobulin therapy, specialist review of patient clinical status and immunoglobulin products, in addition to selection of appropriate treatment strategy for the management of patients with associated side effects and adverse events, are crucial.

IgG anti-IgA antibodies in paediatric antibody-deficient patients receiving intravenous immunoglobulin

BACKGROUND

Immunoglobulin replacement therapy is an effective route of management for both infections and non-infectious complications in predominantly antibody deficiency (PAD). Trace levels of IgA (ranged from 0.4 to 2500 mg/ml), which exist in all immunoglobulin products, could lead to an increased susceptibility for adverse reactions in PAD patients. Furthermore, the exact mechanism which stimulates the anti-IgA antibody production in PAD is still unknown. The aim of this study was to evaluate IgG anti-IgA antibodies in PAD patients receiving intravenous immunoglobulin (IVIg) and its predisposing factors.

METHODS

Available patients with confirmed diagnosis of PAD, who underwent regular IVIg replacement therapy in our centre, were enrolled in the study. Control group included 24 healthy individuals as the negative control and eight symptomatic patients with IgA deficiency as the positive control groups. IgG anti-IgA antibodies level was measured by the ELISA method.

RESULTS

A significant difference was observed between Anti-IgA level of common variable immunodeficiency (CVID) and other PAD groups (p=0.02). Moreover, six CVID patients were seropositive for the IgG anti-IgA antibody, with higher susceptibility to the adverse reactions (p<0.001). IgG anti-IgA level has a negative relationship with serum IgA level (r=-0.06) and IVIg treatment duration (r=-0.006).

CONCLUSION

Our data suggested that there was a significant association between anti-IgA antibody presence and the adverse reactions, especially in CVID patients with higher susceptibility to produce this constitutional antibody.

The expanding role of therapeutic antibodies

Therapeutic antibodies have been used since the end of nineteenth century, but their use is progressively increased and recently, with the availability of monoclonal antibodies, they are successfully employed in a large disease spectrum, which transversally covers different fields of medicine. Hyperimmune polyclonal immune globulin has been used against infectious diseases, in a period in which anti-microbial drugs were not yet available, and it still maintains a relevant place in prophylaxis/therapy. Although immune globulin should be considered life-saving as replacement therapy in humoral immunodeficiencies, its place in the immune-modulating treatment is not usually first-choice, but it should be considered as support to standard approved treatments. Despite therapeutic monoclonal antibodies have been lastly introduced in therapy, their extreme potentiality is reflected by the large number of approved molecules, addressed toward different immunological targets and able to heavily influence the prognosis and quality of life of a wide range of different diseases.

A review on guidelines for management and treatment of common variable immunodeficiency

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency in adults. As symptoms of CVID are usually heterogeneous and unspecific, diagnosis and follow-up of CVID can be challenging. In light of this, a broad review of advances in management and treatment of CVID is performed here in order to reach a distinct protocol. However, it should be noted that owing to the nature of the disease, it can only be treated symptomatically but not cured. There is little evidence to guide appropriate or universal guidelines to improve the current status of management of the disease. The most satisfactory treatments of CVID could be achieved by the use of immunoglobulin replacement, antibiotics, immunosuppressants and hematopoietic stem cell transplantation. This review is written based on the importance of clinical surveillance of asymptomatic CVID cases and early recognition of different clinical complications. Moreover, for each complication, appropriate interventions for improving outcomes are mentioned.

A novel splice variant of FcγRIIa: a risk factor for anaphylaxis in patients with hypogammaglobulinemia

BACKGROUND

Our index case was a patient with common variable immunodeficiency (CVID). She had anaphylactoid reactions on administration of intravenous immunoglobulin (IVIg) associated with the presence of IgG antibodies against IgA.

OBJECTIVE

We sought to determine the role of Fcγ receptor (FcγR) IIa in IVIg-induced anaphylactoid reactions.

METHODS

Neutrophils and PBMCs were isolated from healthy subjects and IVIg-treated patients. FcγRIIa mRNA and DNA were analyzed by using real-time PCR and sequencing. IgG-mediated elastase release and intracellular Ca(2+) mobilization were determined in neutrophils and transfected cell lines, respectively.

RESULTS

A novel splice variant of FcγRIIa containing an expressed cryptic exon 6* (FcγRIIa(exon6∗)) was identified in our index patient. This exon is normally spliced out of all FcγRII isoforms, except the inhibitory FcγRIIb1. Compared with healthy control subjects, the heterozygous FCGR2A(c.742+871A>G) mutation was more frequent in patients with CVID (n = 53, P < .013). Expression in patients with CVID was associated with anaphylaxis on IVIg infusion (P = .002). On screening of additional IVIg-treated patient cohorts, we identified 6 FCGR2A(c.742+871A>G) allele-positive patients with Kawasaki disease (n = 208) and 1 patient with idiopathic thrombocytopenia (n = 93). None had adverse reactions to IVIg. Moreover, FcγRIIa(exon6∗) was also demonstrated in asymptomatic family members. Functional studies in primary cells and transfected murine cells demonstrated enhanced cellular activation by FcγRIIa(exon6∗) compared with its native form, as shown by increased elastase release and intracellular calcium mobilization.

CONCLUSION

A novel splice variant, FcγRIIa(exon6∗), was characterized as a low-frequency allele, coding for a gain-of-function receptor for IgG. In the presence of immune complexes, FcγRIIa(exon6∗) can contribute to anaphylaxis in patients with CVID.

Nursing guidelines for administration of immunoglobulin replacement therapy

Immunoglobulin (Ig) replacement therapy, given as regular infusions of pooled human Ig, is the recognized treatment of humoral immunodeficiencies characterized by hypogammaglobulinemia and impaired antibody responses. It is a safe, effective therapy when delivered by nurses who have been educated to oversee and/or provide these infusions. Guidelines for administration have been developed by the Immune Deficiency Foundation Nurse Advisory Committee to provide a framework and guidance to those nurses administering this therapy.

The safety profile of home infusion of intravenous immunoglobulin in patients with neuroimmunologic disorders

OBJECTIVES

To assess the overall safety of high-dose intravenous immunoglobulin (IG) products used to treat patients with neuroimmunological disorders in a supervised home-based setting.

METHODS

The incidence of adverse reactions was assessed in a retrospective chart review of 420 patients who consecutively received 4076, home-based, individual, intravenous immunoglobulin (IVIG) infusions between January 2009 and December 2009.

RESULTS

A total of 90 patients (21.4%) developed adverse reactions related to IVIG administration (2.6% per individual infusion). A total of 95.5% of adverse reactions were mild, and no serious side effects were observed. The incidence of adverse reactions was significantly lower in the subgroup of patients with neuroimmunological disorders who received premedication (18.2% compared with 29.3%, P = 0.02). There was no significant statistical difference in the incidence of side effects among the different brands of IVIG used in this study.

CONCLUSIONS

The combination of premedication and well-defined clinical, IVIG infusion policies may reduce the incidence of high-dose IVIG adverse reactions administered in a home-based setting in patients with neuroimmunological disorders.

The role of anti-IgA antibodies in causing adverse reactions to gamma globulin infusion in immunodeficient patients: a comprehensive review of the literature

Anaphylactic reactions to immunoglobulin infusions in immunodeficient patients with undetectable IgA have been attributed in several reports to IgG or IgE anti-IgA antibodies. However, other reports have not supported an association between such antibodies and the development of severe reactions. We have reviewed the articles reporting reactions to immunoglobulin products in IgA-deficient patients, as well as those describing the presence of such antibodies in the absence of reactions to infusions. A variety of factors might influence the association of adverse reactions with anti-IgA antibodies, including the serum concentration and isotype (IgG or IgE) of the anti-IgA antibody, its specificity (class or subclass specific), the method of measurement, and the IgA content of the gamma globulin infusion and its route of administration. The role of anti-IgA antibodies in causing anaphylaxis in IgA-deficient patients receiving gamma globulin therapy is still controversial. Larger (multicenter) studies are needed to further evaluate this association.

Profile of autoantibodies against phosphorylcholine and cross-reactivity to oxidation-specific neoantigens in selective IgA deficiency with or without autoimmune diseases

Immunoglobulin A deficiency (IgAD) is considered the most common form of primary immunodeficiency. The majority of IgA-deficient individuals are considered asymptomatic, even though IgAD has been associated with an increased frequency of recurrent infections, allergy, and autoimmune diseases. In this study we evaluate the Natural autoantibodies (NatAbs) reactivity to phosphorylcholine (PC) and to some pro-inflammatory molecules in IgAD with or without autoimmune disorders. We observed that in the absence of IgA there is an enhancement of IgG subclasses functioning as NatAbs against PC. Immunoglobulin G (IgG) against lipopolysaccharide, C-reactive protein, and IgA was found in IgAD, regardless of the autoimmune manifestations. Nonetheless, IgAD patients with autoimmune disease showed significantly higher IgG reactivity against pro-inflammatory molecules, such as cardiolipin, oxidized low-density lipoproteins, and phosphatidylserine, with positive correlation between them. In conclusion, the IgG NatAbs against PC may represent a compensatory defense mechanism against infections and control excess of inflammation, explaining the asymptomatic status in the IgA deficiency.

Immunoglobulin replacement therapy in children

The benefit of immunoglobulin (IG) replacement in primary antibody deficiencies is unquestionable. Many of these congenital disorders present early in life and this therapy is often first implemented in the young. This article focuses on the indications of IG replacement in children, with an emphasis on the specific diagnostic problems encountered in this population. Also presented is an overview of the practical aspects of IG administration in the pediatric setting, including the recognition and management of adverse reactions. Finally, the advent of subcutaneous IG, a therapeutic IG modality with the potential to have a great impact on the quality of life of children with antibody deficiencies and their families, is discussed.

Prospective study on CVID patients with adverse reactions to intravenous or subcutaneous IgG administration

INTRODUCTION

The multicenter prospective study provides information on adverse reactions to intravenous and subcutaneous immunoglobulin treatment in a cohort of 262 patients with common variable immunodeficiency. Severe adverse reactions are a rare but unpredictable event that might occur also in patients who tolerate substitutive intravenous or subcutaneous immunoglobulin therapy for months or years.

RESULTS

Subcutaneous therapy has been proved to be a safe option in the 13 patients who had to stop intravenous treatment and who remained out of immunoglobulin replacement for long periods of time. However, severe reactions to subcutaneous therapy occurred at the first or after several subcutaneous immunoglobulin administrations in 2 out of 13 patients.

CONCLUSION

Therefore, patients with previous severe reactions to intravenous immunoglobulin should be considered at particularly high risk for reaction to subcutaneous administration. In these cases, switching from in-hospital administration to home self-administration should be done with extreme care.

Common variable immunodeficiency: a new look at an old disease

Primary immunodeficiencies comprise many diseases caused by genetic defects primarily affecting the immune system. About 150 such diseases have been identified with more than 120 associated genetic defects. Although primary immunodeficiencies are quite rare in incidence, the prevalence can range from one in 500 to one in 500 000 in the general population, depending on the diagnostic skills and medical resources available in different countries. Common variable immunodeficiency (CVID) is the primary immunodeficiency most commonly encountered in clinical practice, and appropriate diagnosis and management of patients will have a significant effect on morbidity and mortality as well as financial aspects of health care. Advances in diagnostic laboratory methods, including B-cell subset analysis and genetic testing, coupled with new insights into the molecular basis of immune dysfunction in some patients with CVID, have enabled advances in the clinical classification of this heterogeneous disease.

Structure-function studies for in vitro chemical inhibition of Fc? receptor?mediated phagocytosis

BACKGROUND

Previous studies [Transfusion 2005;45:384] showed that certain chemical compounds containing sulfur-reactive groups can inhibit Fcgamma receptor (FcgammaR)-mediated phagocytosis in vitro. These studies, however, did not prove that only sulfur functionality-induced reactivity was efficacious. In an effort to develop a drug-based approach for the future treatment of immune-mediated cytopenias, these earlier findings have now been extended and this chemically induced interference with FcgammaR-mediated phagocytosis of anti-D-coated red cells (RBCs) was examined to assess the optimal structural requirements for the inhibitory effect.

STUDY DESIGN AND METHODS

Chemical compounds were purchased or synthesized and used for the assessment of which chemical moiety(-ies) were required for successful inhibition of in vitro phagocytosis of anti-D-coated RBCs with a monocyte monolayer assay.

RESULTS

Using compounds having similar structures but differences in reactive moieties, it was proved that the only chemical moiety that was required for inhibition of FcgammaR-mediated phagocytosis in vitro was a disulfide bond. It is also shown, however, that a p-nitrophenyl group provides significant enhancement to the inhibitory effect of disulfide-containing compounds. Involvement of carbonyl and hydroxyl functional groups was also able to be ruled out.

CONCLUSION

Our results confirm and extend previous studies that suggested that only those compounds that target free sulfhydryl groups on the monocyte-macrophage are most effective at blocking phagocytosis of antibody-coated RBCs in vitro. It is also shown that p-nitrophenyl substituent groups have an enhancing effect on the efficacy of disulfide bond-containing compounds. These findings should aid in the design of a drug-based approach for the future treatment of immune cytopenias.

Establishment of an immunoglobulin�A?deficient blood donor registry with a simple in-house screening enzyme-linked immunosorbent assay

BACKGROUND

Transfusion of blood products to immunoglobulin A (IgA)-deficient patients who have developed IgA antibodies can result in serious adverse reactions. To prepare compatible blood components for these patients, blood centers usually maintain a list of IgA-deficient blood donors. An in-house enzyme-linked immunosorbent assay (ELISA) was used to identify new IgA-deficient blood donors.

STUDY DESIGN AND METHODS

An in-house ELISA was used to screen blood samples. IgA-deficient samples, defined as an IgA level below 0.05 mg per dL, were sent to the American Red Cross for confirmatory testing.

RESULTS

Seventy-three confirmed IgA-deficient blood donors were identified among 38,759 screened blood donor samples (frequency, 1:531). IgA antibodies were found in 39 of these 73 blood donors (53%), although only 9 donors had a history of adult IgA exposure (transfusion or pregnancy).

CONCLUSIONS

With a simple in-house ELISA, 73 blood donors were identified as IgA-deficient. From this number, 34 donors, without detectable anti-IgA in their plasma, were added to our IgA-deficient blood donor panel to maximize the management of our inventory of IgA-deficient frozen blood components.

Anti-IgA antibodies in common variable immunodeficiency (CVID): diagnostic workup and therapeutic strategy

Common Variable Immunodeficiency (CVID) patients who are seropositive for anti-IgA antibodies have a predisposition for anaphylactoid reactions to intravenous immunoglobulin replacement therapy (IVIG). Among 88 CVID patients, we identified eight with IgG anti-IgA antibodies (9%). All eight completely lacked IgA (<0.0009 g/l). Five of them had a history of anaphylactoid reactions to IVIG. However, four of these five patients tolerated subcutaneous immunoglobulin replacement therapy (SCIG). To identify predisposing factors for anti-IgA antibodies and related anaphylactoid reactions, we analyzed the clinical and immunological phenotype of affected patients. All eight IgG anti-IgA-positive patients lacked IgA(+) B cells in peripheral blood. Moreover, CVID patients with retained class-switched CD27(pos) IgM(neg) IgD(neg) memory B cells (Freiburg classification group II) and total IgA deficiency seem to have an increased risk for developing anti-IgA antibodies. In seven of the eight patients, lymphoproliferation was observed (most prominently nodular lymphatic hyperplasia), two had granulomatous disease, and two showed autoimmune phenomena.

Intravenous immunoglobulin: striving for appropriate use

BACKGROUND

Intravenous immunoglobulin (IVIG) is the mainstay therapy in human immune deficiency states characterized by qualitative and quantitative reductions in B cells. In addition, however, there is widespread use of IVIG in a number of other areas, including neuroimmunologic, infectious, dermatologic, hematologic, autoimmune, inflammatory and idiopathic disorders. In many of these cases, there are little objective data to support the use.

METHODS

We performed a review of more than 400 publications in PubMed using the key words 'intravenous immunoglobulin' and excluded publications that focused on immune deficiency, for which the indication for IVIG is already clear.

RESULTS

For a number of off-label indications, there is significant evidence of efficacy and IVIG has become the standard of care for many clinical syndromes other than immune deficiency. In some conditions, however, the data have not been well controlled or randomized and are often limited to case reports that are difficult to interpret. Although the critical shortage of IVIG of the last decade is no longer an issue, IVIG is expensive and not without risk. The use of IVIG should be based not only on clinical data, but also, and especially, on the biological rationale for its use.

CONCLUSIONS

The appropriate use of IVIG is an important issue that is difficult to resolve, and will continue to challenge clinicians based on expense and potentially limited supply, including the intrinsic limitations of donor plasma. The establishment of national and international voluntary registries to report use of IVIG in disorders for which evidence is lacking would be a first step toward facilitating randomized, controlled clinical trials.

Developing practice guidelines for the administration of intravenous immunoglobulin

As the use of intravenous immunoglobulin (IGIV) continues to expand, infusion nurses have a greater need for a comprehensive understanding of the product, patient risk factors, and comorbidities when developing guidelines for administering IGIV. Because immunoglobulin therapy is a blood derivative product, many nurses may not have as much experience administering this type of infusion. This article provides an in-depth overview of immunoglobulin therapy and helps to define the infusion nurse's major role in coordinating, assessing, and ensuring patient safety during IGIV administration.

A new strategy for the prevention of IgA anaphylactic transfusion reactions

BACKGROUND

Management of patients with clinically significant anti-IgA is difficult and unsatisfactory in many aspects.

PATIENTS AND METHOD

A 40-year-old man with common variable immunodeficiency had a previous history of anaphylaxis after an intramuscular immunoglobulin administration. His serum contained anti-IgA, and he required immunoglobulins for recurrent infections.

RESULTS

The administration of intravenous immunoglobulins (IVIgG) containing less than 0.1 mg per mL IgA led to an anaphylactic reaction after the transfusion of only 2 to 3 mL. The same IVIgG charge was subsequently pretreated with freshly separated autologous plasma and given to the patient on three consecutive days without any reaction (1.25, 10, and 10 g each in 400 mL plasma). Anti-IgA activity did not increase, and the patient was treated again without complications.

DISCUSSION

Ex vivo pretreatment of IVIgG preparations with autologous plasma appears to be safe and useful in the management of patients with clinically significant anti-IgA. To achieve a significant IgA blockage, the preparation to be used should not contain large amounts of IgA.

CONCLUSION

The strategy described here appears to be safe and may help prevent anaphylaxis in many instances.

Adverse reactions of prophylactic intravenous immunoglobulin infusions in Iranian patients with primary immunodeficiency

BACKGROUND

Although long-term intravenous immunoglobulin infusion is an effective treatment for children with antibody deficiencies, it can be complicated by systemic adverse reactions.

OBJECTIVE

To evaluate the adverse reactions of intravenous immunoglobulin therapy in patients with primary immunodeficiency.

METHODS

Seventy-one immunodeficient patients receiving intravenous immunoglobulin were evaluated during a 7-year period (1995-2002) at Children's Medical Center in Tehran, Iran. Immunological diagnoses were as follows: common variable immunodeficiency (31 patients), X-linked agammaglobulinemia (25 patients), IgG subclass deficiency (5 patients), hyper-IgM syndrome (2 patients), and ataxia-telangiectasia (8 patients).

RESULTS

One hundred fifty-two cases (12.35%) of adverse reactions occurred following 1,231 infusions in 35 patients. The most frequent immediate adverse reactions were mild reactions (131 infusions), including chills, fever, flushing, muscle pains, nausea, headache, and anxiety. Moderate reactions, such as vomiting, chest pain, and wheezing, occurred in 19 infusions. Two patients experienced severe adverse reactions. The highest proportion (23.06%) of reaction to injection was in patients with common variable immunodeficiency.

CONCLUSIONS

Intravenous immunoglobulin is a well tolerated medical agent for patients with antibody deficiency. However, to prevent occurrence of immediate adverse reactions during infusion in these patients, physicians should perform a detailed history and proper physical examination and check the titer of anti-IgA.

Anaphylactic transfusion reactions

PURPOSE OF REVIEW

Although anaphylactic reactions to blood products are rare, the incidence of allergic reactions to blood products is similar to the allergic reaction incidence to penicillin antibiotics, and therefore worthy of proportionate attention. Comprehensive reviews and guidelines of the management of anaphylaxis currently do not include much information on blood products. Current guidelines for the specific management of anaphylactic transfusion reactions are contradictory as to the utility of anti-IgA testing and incomplete by not offering suggestions for the management of non-IgA related reactions.

RECENT FINDINGS

Anti-IgA is not responsible for most reactions. Anti-haptoglobin antibodies are responsible for more reactions than anti-IgA in Japan, but the cause of most reactions is still not known. The incidence of reactions to platelets is the highest compared with fresh frozen plasma and red blood cells. Pre-storage white blood cell reduction of platelets does not decrease the incidence of reactions, indicating that white blood cell-derived cytokines are not responsible for most reactions.

SUMMARY

The increased incidence of reactions to platelets compared with fresh frozen plasma suggests that a platelet-related factor may be responsible for many of the reactions. The possible role of platelet microparticles or activated platelet membranes, which carry a negative charge similar to ionic radiocontrast media, the major cause of iatrogenic anaphylactic reactions in the hospital, is explored.

Rapid detection of antibodies to immunoglobulin A molecules by using the particle gel immunoassay

BACKGROUND AND OBJECTIVES

Antibodies to immunoglobulin A (IgA) molecules are thought to be frequently responsible for anaphylactic reactions in transfusion medicine, but practical tests for the detection of antibodies to IgA are not yet available.

MATERIAL AND METHODS

Red, high-density polystyrene beads were coated with purified IgA molecules and then used to test serum samples collected from unselected healthy blood donors (n = 105) and patients with common variable immunodeficiency and/or IgA deficiency (n = 44). For testing, the standard gel-agglutination technique (ID-Micro Typing System) was employed.

RESULTS

None of the normal serum samples were reactive with IgA-coated beads and samples from only 10 patients were positive (titre range 1 : 2 to 1 : 256). Only one out of all patients studied had a history of an anaphylactic reaction and this was related to the administration of Rh(D) prophylaxis (anti-D immunoglobulin). The beads did not show non-specific agglutination and could be used repeatedly for longer than 6 months. The results were reproducible in all patients tested.

CONCLUSION

The new test allows a specific and rapid detection of antibodies to IgA molecules. In order to evaluate the clinical relevance of the test, analysis is required of a wider range of antibodies that produce anaphylactic reactions.