The Middle East and North Africa Diagnosis and Management Guidelines for Inborn Errors of Immunity

Human inborn errors of immunity (IEI) are a group of 485 distinct genetic disorders affecting children and adults. Signs and symptoms of IEI are heterogeneous, and accurate diagnosis can be challenging and depends on the available human expertise and laboratory resources. The Middle East and North Africa (MENA) region has an increased prevalence of IEI because of the high rate of consanguinity with a predominance of autosomal recessive disorders. This area also exhibits more severe disease phenotypes compared with other regions, probably due to the delay in diagnosis. The MENA-IEI registry network has designed protocols and guidelines for the diagnosis and treatment of IEI, taking into consideration the variable regional expertise and resources. These guidelines are primarily meant to improve the care of patients within the region, but can also be followed in other regions with similar patient populations.

Epidemiology, clinical characteristics, and treatment of severe fever with thrombocytopenia syndrome

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne infectious disease caused by a novel phlebovirus (SFTS virus, SFTSV) in the family Phenuiviridae of the order Bunyavirales. The disease causes a wide spectrum of clinical signs and symptoms, ranging from mild febrile disease accompanied by thrombocytopenia and/or leukocytopenia to hemorrhagic fever, encephalitis, multiple organ failure, and death. SFTS was first identified in China and was subsequently reported in South Korea and Japan. The case-fatality rate ranges from 2.7% to 45.7%. Older age has been consistently shown to be the most important predictor of adverse disease outcomes. Older age exacerbates disease mainly through dysregulation of host immune cells and uncontrolled inflammatory responses. Tick-to-human transmission is the primary route of human infection with SFTSV, and Haemaphysalis longicornis is the primary tick vector of SFTSV. Despite its high case-fatality rate, vaccines and antiviral therapies for SFTS are not currently available. The therapeutic efficacies of several antiviral agents against SFTSV are currently being evaluated. Ribavirin was initially identified as a potential antiviral therapy for SFTS but was subsequently found to inefficiently improve disease outcomes, especially among patients with high viral loads. Favipiravir (T705) decreased both time to clinical improvement and mortality when administered early in patients with low viral loads. Anti-inflammatory agents including corticosteroids have been proposed to play therapeutic roles. However, the efficacy of other therapeutic modalities, such as convalescent plasma, is not yet clear.

Potential therapeutic approach of intravenous immunoglobulin against COVID-19

Since the outbreak of the novel coronavirus disease (COVID-19), the therapeutic and management options to reduce the burden of the COVID-19 disease are under investigation. IVIG therapy is used as an effective treatment for immunodeficient patients and patients with inflammatory or autoimmune conditions. The therapeutic effect of IVIG in COVID-19 patients has been investigated. But, the results are controversial and some studies reported no benefit of IVIG therapy. More clinical trials on the effect of IVIG therapy in COVID-19 patients should be performed to establish a certain conclusion about IVIG effectiveness.

Adverse reactions in a large cohort of patients with inborn errors of immunity receiving intravenous immunoglobulin

BACKGROUND

Intravenous immunoglobulins (IVIg) are the major treatment in inborn errors of immunity (IEI) disorders; However, IVIg infusions show some adverse effects. We aimed to assess the adverse reactions of IVIg infusions.

METHODS

Data of IVIg infusions in IEI patients were collected from 2011 to 2021. Totally, 363 IEI patients received IVIg regularly in Iran entered the study. The adverse reactions are classified regarding their severity and chronicity.

RESULTS

22,667 IVIg infusions were performed in the study. 157 patients (43.2%) and 1349 (5.9%) infusions were associated with at least one type of adverse reaction. The highest rates of adverse reactions were seen in severe combined immunodeficiency. Myalgia, chills, headache, fever, and hypotension were the most frequent adverse effects of IVIg.

CONCLUSION

The reactions affect almost half of the patients mainly in the first infusions which necessitate the close observation of IEI patients receiving IVIg.

[Use of intravenous and subcutaneous human immunoglobulins]

Immunoglobulin preparations are medicines derived from blood used as a replacement therapy for immunodeficiencies or as an immunomodulator. While they are generally well-tolerated, side effects, rarely severe, can nevertheless occur when administered intravenously. They are usually related to an excessive perfusion rate. The recent arrival of safer products administered subcutaneously represents progress in the treatment of patients.

Changes in Hemoglobin Concentrations Post-immunoglobulin Therapy in Patients with Kawasaki Disease: A Population-Based Study Using a Claims Database in Japan

BACKGROUND

We sought to quantify the degree of anemia after high-dose intravenous immunoglobulin (IVIG) therapy in patients with Kawasaki disease (KD) by assessing hemoglobin (Hb) dynamics and determining the risk of transfusion.

METHODS

We analyzed data from a database containing inpatient data collected from 230 hospitals in Japan. In addition to administrative records, this database included laboratory results for some patients. We searched for individuals aged ≤ 18 years with a diagnosis of KD (International Statistical Classification of Diseases and Related Health Problems, 10th revision, code M30.3) who had received high-dose (≥ 1 g/kg) IVIG therapy. The primary outcome measure was post-IVIG therapy Hb dynamics in patients for whom laboratory findings were available. Secondary outcomes included the proportion of patients whose Hb value decreased below a specified threshold (e.g., 1 g/dL) and the number who received red blood cell transfusions, identified by a Japanese administrative code, in the whole cohort.

RESULTS

Laboratory data were available for 979 of 8262 patients with KD receiving high-dose IVIG. Hb dynamics assessed on spline curves showed that mild anemia commonly occurred 1-2 days after IVIG infusion and returned to the baseline thereafter. Declines of Hb > 1 g/dL and > 2 g/dL were found in 21.8% and 4.3% of patients, respectively. Two of the 8262 individuals with KD had received transfusions after IVIG therapy (incidence rate 0.024%; 95% confidence interval 0.003-0.087), but the indication for transfusion could not be determined from our records.

CONCLUSIONS

Although mild anemia commonly occurred post-IVIG therapy in Japanese individuals with KD, severe anemia necessitating transfusion was rare in these patients.

The hyper IgM syndromes: Epidemiology, pathogenesis, clinical manifestations, diagnosis and management

Hyper Immunoglobulin M syndrome (HIGM) is a rare primary immunodeficiency disorder characterized by low or absent levels of serum IgG, IgA, IgE and normal or increased levels of serum IgM. Various X-linked and autosomal recessive/dominant mutations have been reported as the underlying cause of the disease. Based on the underlying genetic defect, the affected patients present a variety of clinical manifestations including pulmonary and gastrointestinal complications, autoimmune disorders, hematologic abnormalities, lymphoproliferation and malignancies which could be controlled by multiple relevant therapeutic approaches. Herein, the epidemiology, pathogenesis, clinical manifestations, diagnosis, management, prognosis and treatment in patients with HIGM syndrome have been reviewed.

Cost-effectiveness analysis of subcutaneous immunoglobulin replacement therapy in Iranian patients with primary immunodeficiencies

Background: Economic evaluation of subcutaneous immunoglobulin therapy (SCIG) is important, and it has recently been used for treatment of patients with primary immunodeficiency (PID) diseases, and can improve allocation of resources in health care systems. The present research aimed at providing an economic assessment of SCIG and IVIG (intravenous immunoglobulin therapy) administration in Iran. Methods: Data related to clinical effectiveness were obtained from a meta-analysis. Economic analysis was performed taking into account the perspective of health care providers. Incremental cost-effectiveness ratio (ICER) was applied for economic evaluation of the 2 methods, and GDP per capita was considered as a threshold. Results: The results of meta-analysis suggested a higher effectiveness of SCIG compared to IVIG in serum immunoglobulin (Ig) levels (SMD= 0.336) and adverse effects (OR= 0.497), while the cost of IVIG was higher than SCIG ($1370 vs. $121). The ICER obtained in this paper ($2939 for adverse effects and $4348 for serum Ig level) was less than the GDP per capita in Iran ($4,916.10), and thus SCIG is a more cost-effective therapy for PID patients. Conclusion: Switching from IVIG to SCIG is cost-effective for PID patients and is approved by the health care providers' points of view in this study.

Epidemiology and pathophysiology of malignancy in common variable immunodeficiency?

Common variable immunodeficiency (CVID) is a diagnostic category of primary immunodeficiency (PID) which may present with heterogeneous disorders including recurrent infections, autoimmunity, granulomatous diseases, lymphoid and other types of malignancies. Generally, the incidence of malignancy in CVID patients is around 1.5-20.7% and usually occurs during the 4th-6th decade of life. Non-Hodgkin lymphoma is the most frequent malignancy, followed by epithelial tumours of stomach, breast, bladder and cervix. The exact pathological mechanisms for cancer development in CVID are not fully determined; however, several mechanisms including impaired genetic stability, genetic predisposition, immune dysregulation, impaired clearance of oncogenic viruses and bacterial infections, and iatrogenic causes have been proposed to contribute to the high susceptibility of these patients to malignancies.

Measurement of Health-Related Quality of Life in Primary Antibody-Deficient Patients

BACKGROUND

Primary immunodeficiency diseases are a group of disorders that result from a variety of defects of the immune system. Primary antibody deficiencies (PADs) are the most common forms of these disorders. Occurrence of recurrent infections, autoimmune diseases, cancers, and lymphoproliferative disorders is higher in PAD patients. Chronicity of these diseases, delayed diagnosis, inadequate treatment, and treatment side effects may affect the quality of life (QoL) of PAD patients. Evaluating QoL is important for patient care, understanding the burden of these diseases, and finding the patients' major health problems. We investigated the QoL in a group of PAD patients undergoing regular follow-up and treatment at the Children's Medical Center Hospital in Tehran, Iran.

METHODS

Seventy patients with a diagnosis of PAD in two age groups (younger and older than 18 years) were included. QoL was measured using PedsQL and SF-36 questionnaires. Correlation of demographic, clinical, and immunological parameters with QoL scores was assessed and patients' scores were compared with the normal population, using nonparametric tests of SPSS software.

RESULTS

Patients expressed significantly reduced scores in some mental and physical components. Patients with longer follow-up periods had higher scores in mental components but physical component scores were still low. There was no significant correlation between sex, age, and disease types with scores.

CONCLUSIONS

PAD patients had significantly lower scores in mental and physical components compared to normal population. By early diagnosis and long-term follow-up periods, we may be able to prevent complications and help patients to have a better QoL.

A Comparative Study of Intravenous Immunoglobulin and Subcutaneous Immunoglobulin in Adult Patients with Primary Immunodeficiency Diseases: A Systematic Review and Meta-Analysis

Subcutaneous immunoglobulin (SCIG) is a new therapeutic procedure for patients with primary immunodeficiency (PI). This research is a systematic review of studies on the efficacy and safety of intravenous immunoglobulin (IVIG) and SCIG in adult patients with PI. This study includes a systematic review of cohorts and randomized clinical trials (24 articles) from 5 databases with no time limits. Random effects meta-analysis was performed for outcomes such as efficacy and safety. Standard mean difference (SMD) of serum immunoglobulin level was equal to 0.336 (P <0.01; 0.205-0.467) and the odds ratio (OR) of side effects was 0.497 (P=0.1; 0.180-1.371). The results indicate that SCIG leads to a higher level of immunoglobulin and a reduction in side effects but shows the same infection rate as IVIG. Our analysis shows that shifting from IVIG to SCIG therapy can have clinical benefits for PI patients.

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.

Economic burden of common variable immunodeficiency: annual cost of disease

OBJECTIVES

In the context of the unknown economic burden imposed by primary immunodeficiency diseases, in this study, we sought to calculate the costs associated with the most prevalent symptomatic disease, common variable immunodeficiency (CVID).

METHODS

Direct, indirect and intangible costs were recorded for diagnosed CVID patients. Hidden Markov model was used to evaluate different disease-related factors and Monte Carlo method for estimation of uncertainty intervals.

RESULTS

The total estimated cost of diagnosed CVID is US$274,200/patient annually and early diagnosis of the disease can save US$6500. Hospital admission cost (US$25,000/patient) accounts for the most important expenditure parameter before diagnosis, but medication cost (US$40,600/patients) was the main factor after diagnosis primarily due to monthly administration of immunoglobulin.

CONCLUSION

The greatest cost-determining factor in our study was the cost of treatment, spent mostly on immunoglobulin replacement therapy of the patients. It was also observed that CVID patients' costs are reduced after diagnosis due to appropriate management.

Mortality and morbidity in patients with X-linked agammaglobulinaemia

BACKGROUND

X-linked agammaglobulinaemia (XLA) is a genetic disorder characterised by a defect in the generation of mature B cells, lack of antibodies production, and susceptibility to recurrent bacterial infections. Understanding of the risk factors responsible for morbidity and mortality in these patients can help in a better management of this disorder. However, there is a lack of specific studies in the literature regarding the morbidity and mortality of XLA patients. This study is designed to evaluate morbidities and mortality and survival rates in Iranian patients with XLA diagnosis during the past 20 years.

METHODS

We have registered the clinical data of the XLA patients and followed them up until 2010. At the time of diagnosis, a four-page questionnaire including complete medical information was filled out for all patients. Follow-up information was gathered either by reviewing the patients' hospital records or regularly visiting the patients.

RESULTS

Among 41 patients, 26.8% died during the follow up period. All of the complications before the initiation of treatment such as pneumonia, otitis media and diarrhoea were reduced after immunoglobulin replacement, except sinusitis and conjunctivitis. There were significant associations between some immunological and clinical characteristics such as lymphocyte subsets, consanguinity marriage and mortality.

CONCLUSION

Despite recent advances in the treatment of XLA, these patients still suffer from severe complications. Associations between poor prognosis and clinical and some immunological characteristics of the patients may help physicians to select poor prognoses patients at higher risk of mortality to develop prevention strategies for them.

Effects of intravenous immunoglobulins on mice with experimental epidermolysis bullosa acquisita

Although well-designed prospective trials are generally lacking, intravenous immunoglobulins (IVIG) seem an effective adjuvant treatment for autoimmune bullous skin diseases. Here, efficacy of IVIG monotherapy was compared with corticosteroid treatment in mice with immunization-induced experimental epidermolysis bullosa acquisita (EBA), an autoimmune bullous skin disease characterized by autoantibodies against type VII collagen. We found that IVIG significantly ameliorated clinical disease severity and skin neutrophil infiltration compared with vehicle-treated mice, whereas methylprednisolone showed comparatively less pronounced effects. Efficacy of IVIG was accompanied by reduced levels of autoantibodies, a shift toward noncomplement-fixing autoantibodies, and lower complement deposition at the dermal-epidermal junction. In addition, peripheral Gr-1-positive cells of IVIG-treated animals showed reduced expression of the activating Fcγ receptor IV, which we recently described as a major mediator of tissue injury in experimental EBA. These data show that treatment with IVIG is superior to systemic corticosteroids in experimental EBA and that the effects of IVIG are pleiotropic involving modulation of both the adaptive and innate immune response, although the detailed mode of action of IVIG in this model remains in need of further elucidation.

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.

Polyclonal and monoclonal antibodies in clinic

Immunoglobulins (Ig) or antibodies are heavy plasma proteins, with sugar chains added to amino-acid residues by N-linked glycosylation and occasionally by O-linked glycosylation. The versatility of antibodies is demonstrated by the various functions that they mediate such as neutralization, agglutination, fixation with activation of complement and activation of effector cells. Naturally occurring antibodies protect the organism against harmful pathogens, viruses and infections. In addition, almost any organic chemical induces antibody production of antibodies that would bind specifically to the chemical. These antibodies are often produced from multiple B cell clones and referred to as polyclonal antibodies. In recent years, scientists have exploited the highly evolved machinery of the immune system to produce structurally and functionally complex molecules such as antibodies from a single B clone, heralding the era of monoclonal antibodies. Most of the antibodies currently in the clinic, target components of the immune system, are not curative and seek to alleviate symptoms rather than cure disease. Our group used a novel strategy to identify reparative human monoclonal antibodies distinct from conventional antibodies. In this chapter, we discuss the therapeutic relevance of both polyclonal and monoclonal antibodies in clinic.

Comparison of the glycosylation of in vitro generated polyclonal human IgG and therapeutic immunoglobulins

We have recently developed an in vitro culture model enabling the large-scale expansion of switched-memory B lymphocytes, producing a polyclonal human IgG repertoire. Given the importance of glycosylation for the functions of immunoglobulins, we analyzed the N-glycosylation profiles of the immunoglobulin G (IgG) in this model. Switched-memory B cells were cultured for 38 days and, using liquid chromatography-mass spectrometry, we analyzed IgGs' glycosylation profiles which were then compared to the glycosylation patterns of commercial intravenous immunoglobulin (IVIG). We observed a reproducible proliferation rate, high viability through the cultures as well as a good maintenance of the switched-memory B cells repertoire. The glycosylation pattern analyses revealed a variety of the typical biantennary N-glycan structures with diverse terminal monosaccharides. While many similarities were detected in comparison to the glycosylation profile of IVIG, in vitro-produced polyclonal IgGs were bearing higher levels of bisecting GlcNAc known to affect the effector functions of therapeutic antibodies. This data highlights the need for monitoring of the glycoform distribution in antibodies produced in vitro.

[Intravenous immunoglobulin treatment in idiopathic inflammatory myopathy]

Idiopathic inflammatory myopathies are chronic, systemic autoimmune diseases, characterized by symmetric and progressive weakness of proximal muscles in the upper and lower extremities. Treatment of the disease presents a complex challenge and it needs practical knowledge. In this review the authors summarize current treatment options, and discuss intravenous immunoglobulin treatment in therapy-unresponsive cases. Relevant data from the international literature is collected, too. Benefits and side effects of this treatment are also disclosed.

Nanoscale reversed-phase liquid chromatography-mass spectrometry of permethylated N-glycans

Reversed-phase liquid chromatography on the nanoscale coupled to electrospray tandem mass spectrometry was used to analyse a mixture of four commercial glycan standards, and the method was further adapted to N-glycans enzymatically released from alpha-1-acid glycoprotein and immunoglobulin gamma. Glycans were permethylated to enable their separation by reversed-phase chromatography and to facilitate interpretation of fragmentation data. Prior to derivatization of glycans by permethylation, they were reduced to cancel anomerism because, although feasible, it was not desired to separate α- and β-anomers. The effect of supplementing chromatographic solvent with sodium hydroxide to guide adduct formation was investigated. Raising the temperature in which the separation was performed improved chromatographic resolution and affected retention times as expected. It was shown by using the tetrasaccharides sialyl Lewis X and sialyl Lewis A that reversed-phase chromatography could achieve the separation of methylated isobaric glycan analytes. Isobaric glycans were detected among the N-glycans of immunoglobulin gamma and further analysed by tandem mass spectrometry.

Novel approaches in the treatment of myositis and myopathies

The inflammatory myopathies are a heterogeneous group of disorders characterized by muscle weakness and inflammation. Although no standard therapeutic guidelines exist, traditional treatment has included corticosteroids and a variety of second-line immunosuppressants. As treatment of refractory disease has been difficult, newer agents and approaches have been used with varying response. The advent of standardized treatment response criteria by the International Myositis Assessment and Clinical Studies (IMACS) group has helped investigators to evaluate and compare clinical trial outcomes in a more rigorous fashion. The use of intravenous immunoglobulin (IVIG), rituximab, biologic agents including tumor necrosis factor (TNF) inhibitors, stem-cell transplantation, gene therapy, and vascular occlusion resistance training are reviewed here. As our understanding of disease pathogenesis at the immunologic, genetic, and molecular level expands, the discovery of novel therapeutic targets hold promise for the successful treatment of these conditions.

New Frontiers in Subcutaneous Immunoglobulin Treatment

Subcutaneous immunoglobulin (SCIG) treatment provides stable serum immunoglobulin G (IgG) levels, is associated with fewer systemic adverse events than intravenous immunoglobulin (IVIG) treatment, and offers the convenience of home therapy. In clinical practice, IVIG is still used preferentially for initiation of treatment in newly diagnosed patients with primary immunodeficiency (PI) and for immunomodulatory therapy, such as treatment of peripheral neuropathies, when high doses are believed to be necessary. The authors discuss recent experience in using SCIG in place of IVIG in these settings. SCIG has been successfully used for initiation of therapy in previously untreated PI patients. Seventeen of 18 PI patients achieved serum IgG levels ≥5 g/L after the loading phase. Daily treatment was well tolerated and provided opportunities for patient/parent training in self-infusion. SCIG has been used for maintenance therapy in multifocal motor neuropathy (MMN) in three recent clinical trials, with good efficacy and tolerability results. Seven of eight MMN patients maintained serum IgG levels of 14–22 g/L with a mean dose of 272 mg/kg/week, had stable muscle strength, and felt comfortable with self-administration. Four patients with polymyositis or dermatomyositis achieved improvement in serum creatine kinase levels and muscle strength with SCIG therapy. Recent experience with SCIG suggests that traditional concepts of immunoglobulin therapy may be challenged to increase available therapy options. SCIG can be used to achieve high IgG levels within several days in untreated PI patients and to maintain high serum levels, as shown in patients with MMN.