Use Of Immunoglobulin Replacement Therapy Research Articles

ВАКЦИНАЦИЯ ДЕТЕЙ С ВРОЖДЕННЫМИ ДЕФЕКТАМИ ИММУНИТЕТА: СОВРЕМЕННЫЕ ПРЕДСТАВЛЕНИЯ О БЕЗОПАСНОСТИ И ЭФФЕКТИВНОСТИ

Primary immunodeficiencies (PIDs) or inborn errors of immunity (IEIs) are a heterogeneous group of genetically-determined diseases that are divided into ten groups according to modern classification. The high heterogeneity in clinical manifestations and pathogenetic mechanisms as well as wide use of immunoglobulin replacement therapy, various immunosuppressant and anti-inflammatory drugs make it difficult to decide on the safety and efficacy of vaccination for patients with IEIs. There are no universally accepted recommendations for vaccine prophylaxis among patients with IEIs both in Russia and Worldwide due to the lack of controlled clinical trials available. Authors have attempted summarizing the bibliographical sources available on the safety and efficacy of vaccine prophylaxis in individuals with different forms of IEIs considering the Authors’ own opinion raising the importance of controlled clinical trials.

Infection Outcomes and Hypogammaglobulinemia in Patients with Chronic Lymphocytic Leukemia Treated with Immunoglobulin Replacement Therapy

CONCLUSIONS Hypogammaglobulinemia (HGG), a secondary immunodeficiency (SID), can manifest in patients with chronic lymphocytic leukemia (CLL) due to the disease and its treatments. Up to half of all deaths from CLL are attributed to infection; however, use of immunoglobulin replacement therapy (IgRT) for the prevention of infections in selected patients varies. We aimed to assess real-world IgRT utilization and infection outcomes in patients with CLL. A retrospective, longitudinal study evaluating real-world IgRT use in adult patients with CLL diagnosed after 2010, with ≥ 3 visits/year and ≥ 12 months of clinical data, was conducted. De-identified clinical data came from the Massachusetts General Brigham Research Patient Data Registry. Immunoglobulin G (IgG) testing, infection outcomes, and antimicrobial use were compared before versus after IgRT initiation. Generalized estimating equation logistic regression models calculated odds ratios (ORs), 95% CIs, and P-values. Of 3960 patients with CLL assessed, 2652 (67.0%) patients had IgG testing (29.0% tested at CLL diagnosis); 917 (34.6%) had HGG (IgG level < 500mg/dL). Median (interquartile range [IQR]) age was 68.0 (60.0, 76.0) years, 61.2% were men, 67.8% were treatment-naïve, and median (IQR) follow-up duration was 4.8 (2.4, 7.4) years. Among recipients of IgRT (n = 259), 56.8% received ≥ 2 administrations and the median (IQR) number of IgRT administrations was 2.0 (1.0, 4.0). Median (IQR) time from CLL diagnosis to IgRT initiation was 38.0 (11.4, 64.7) months. Significantly fewer patients had HGG 3 months after IgRT versus 3 months before (33.8% vs 72.8%; P < 0.0001). Significantly lower odds of infections and antimicrobial use were observed after IgRT initiation in 3- and 6-month time periods for: all infections, sinopulmonary and skin or soft tissue infections, infections requiring antimicrobials, all severe infections, severe sinopulmonary and skin or soft tissue infections, and severe infections requiring antimicrobials ( Table). In this real-world study of patients with CLL, IgRT was associated with significant reductions in HGG, infection rates, and infections requiring antimicrobials. Guidelines are needed to optimize IgG testing, IgRT initiation, and SID management for patients with CLL.

Infections after chimeric antigen receptor (CAR)-T-cell therapy for hematologic malignancies.

Chimeric antigen receptor (CAR)-T-cell therapies have revolutionized the management of acute lymphoblastic leukemia, non-Hodgkin lymphoma, and multiple myeloma but come at the price of unique toxicities, including cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, and long-term "on-target off-tumor" effects. All of these factors increase infection risk in an already highly immunocompromised patient population. Indeed, infectious complications represent the key determinant of non-relapse mortality after CAR-T cells. The temporal distribution of these risk factors shapes different infection patterns early versus late post-CAR-T-cell infusion. Furthermore, due to the expression of their targets on B lineage cells at different stages of differentiation, CD19, and B-cell maturation antigen (BCMA) CAR-T cells induce distinct immune deficits that could require different prevention strategies. Infection incidence is the highest during the first month post-infusion and subsequently decreases thereafter. However, infections remain relatively common even a year after infusion. Bacterial infections predominate early after CD19, while a more equal distribution between bacterial and viral causes is seen after BCMA CAR-T-cell therapy, and fungal infections are universally rare. Cytomegalovirus (CMV) and other herpesviruses are increasingly breported, but whether routine monitoring is warranted for all, or a subgroup of patients, remains to be determined. Clinical practices vary substantially between centers, and many areas of uncertainty remain, including CMV monitoring, antibacterial and antifungal prophylaxis and duration, use of immunoglobulin replacement therapy, and timing of vaccination. Risk stratification tools are available and may help distinguish between infectious and non-infectious causes of fever post-infusion and predict severe infections. These tools need prospective validation, and their integration in clinical practice needs to be systematically studied.

Access and use of immunoglobulins in secondary supportive cancer care: A systematic literature review.

Immunoglobulin replacement therapy (IgRT) benefits patients with primary immuno deficiency (PID) originating from the innate or polygenic defects in the immune system. However, evidence supporting their therapeutic role is not as explicit in secondary immuno deficiency (SID) resulting from the treatment of haematological malignancies. This study aimed to (1) create a dataset of relevant research papers, which explore the use of IgRT in SID for analysis, (2) assess the risk of bias within this dataset and (3) study the characteristics of these papers. This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. In addition to the risk of bias, the study characteristics explored in this article included study design, study geographical location and year of publication. To identify studies relevant to the research question, EMBASE and PubMed databases were searched. The Population, Intervention, Comparison and Outcome (PICO) framework was used to assess study quality. Risk of bias and quality of studies were assessed in accordance with the study design. As one model was not appropriate to assess bias in all articles, several tools were used. A total of 43 studies were identified from the literature search as relevant to the research objective. The most common study design was a retrospective case-control cohort study (n = 16/43), and randomised trials were among the least commonly used approaches (n = 1). Research in this area is occurring around the globe including the United States (n = 7), Italy (n = 7), China, India, Japan and throughout Europe. The annual number of papers in this area has varied from 2012 (n = 1) to 2021 (n = 7). The studies in this article demonstrated a varied risk of bias, with 9 of the 20 cohort studies scoring less than 5 out of 9 stars. Randomised controlled trials are less frequently used to assess access and use of immunoglobulins. More commonly, a retrospective case-control cohort study was used which correlates with the higher risk of bias seen in the studies in this article. Most of the research concerning immunoglobulin use and access occurs in higher-income countries.

British Society for Immunology and United Kingdom Primary Immunodeficiency Network (UKPIN) consensus guideline for the management of immunoglobulin replacement therapy.

SummaryCurrently, there is no guideline to support the use of immunoglobulin replacement therapy (IgRT) in primary and secondary immunodeficiency disorders in UK. The UK Primary Immunodeficiency Network (UK-PIN) and the British Society of Immunology (BSI) joined forces to address this need. Given the paucity of evidence, a modified Delphi approach was used covering statements for the initiation, monitoring, discontinuation of IgRT as well as home therapy programme. A group of six consultant immunologists and three nurse specialists created the statements, reviewed responses and feedback and agreed on final recommendations. This guideline includes 22 statements for initiation, 22 statements for monitoring, 11 statement for home therapy, and 19 statements for discontinuation of IgRT. Further areas of research are proposed to improve future delivery of care.

Therapie von Patient_innen mit Immunschwäche

Treatment of Patients with Immunodeficiency Abstract. Primary, genetically determined immunodeficiencies (PID) are caused by dysfunction of the innate and/or adaptive immune system. The majority of PID present with antibody deficiency, clinically associated with increased susceptibility to airway infections. Infections and pulmonary complications can be reduced by immunoglobulin substitution. The main practical issues of the clinical use of immunoglobulin replacement therapy are discussed here. Molecular dissection of PID is increasingly possible using next generation sequencing, enabling targeted immune modulation and immune reconstitution. This personalized immune modulation is discussed here as a seminal addition to the treatment options in patients with PID.

Controversies about immunoglobulin replacement therapy in HSCT recipients with hypogammaglobulinemia.

The efficacy of immunoglobulin replacement therapy (IgRT) has been demonstrated for primary immune deficiency diseases and hematological malignancies such as chronic lymphocytic leukemia (CLL) or multiple myeloma with hypogammaglobulinemia. Clinical development of anti-B cell therapies including a monoclonal antibody, bispecific antibody, or chimeric antigen receptor T-cell therapy which could result in severe hypogammaglobulinemia accelerates the argument of prophylactic use of IgRT. Clinical guidelines for CLL describe immunoglobulin administration in patients with a low IgG who have experienced a severe/repeated bacterial infection. The utility in hematopoietic stem-cell transplantation (HSCT) remains unknown. Although an early randomized trial demonstrated that IgRT decreased infection risk and transplant-related mortality after HSCT, subsequent clinical trials could not validate the benefit. Consequently, a meta-analysis did not show the benefit of IgRT in HSCT. Most of the available data derives from matched-related HSCT using myeloablative regimen, and the impact in haploidentical and cord blood transplantation, or reduced-intensity HSCT remains unknown. One crucial issue is that no studies exist for patients with only hypogammaglobulinemia after HSCT. Other challenges are heterogeneous patient characteristics, or immunoglobulin formulation, dosage, schedule, route and duration of IgRT. Without evidence in HSCT, it would be reasonable to follow the guidelines for other diseases with hypogammaglobulinemia.

Managing Hypogammaglobulinemia in Patients Treated with CAR-T-cell Therapy: Key Points for Clinicians

Introduction The unprecedented success of chimeric antigen receptor (CAR)-T-cell therapy in the management of B-cell malignancies comes with a price of specific side effects. Healthy B-cell depletion is an anticipated ‘on-target’ ‘off-tumor’ side effect and can contribute to severe and prolonged hypogammaglobulinemia. Evidence-based guidelines for the use of immunoglobulin replacement therapy (IGRT) for infection prevention are lacking in this population. Areas Covered This article reviews the mechanisms and epidemiology of hypogammaglobulinemia and antibody deficiency, association with infections, and strategies to address these issues in CD19- and BCMA-CAR-T-cell recipients. Expert Opinion CD19 and BCMA CAR-T-cell therapy result in unique immune deficits due to depletion of specific B-lineage cells and may require different infection prevention strategies. Hypogammaglobulinemia before and after CAR-T-cell therapy is frequent, but data on the efficacy and cost-effectiveness of IGRT are lacking. Monthly IGRT should be prioritized for patients with severe or recurrent bacterial infections. IGRT may be more broadly necessary to prevent infections in BCMA-CAR-T-cell recipients and children with severe hypogammaglobulinemia irrespective of infection history. Vaccinations are indicated to augment humoral immunity and can be immunogenic despite cytopenias; re-vaccination(s) may be required. Controlled trials are needed to better understand the role of IGRT and vaccines in this population.

PATIENTS WITH SECONDARY HYPOGAMMAGLOBULINEMIA APPROPRIATE FOR ADMINISTRATION AND METHODS OF USE OF IMMUNOGLOBULIN REPLACEMENT THERAPY

PATIENTS WITH SECONDARY HYPOGAMMAGLOBULINEMIA APPROPRIATE FOR ADMINISTRATION AND METHODS OF USE OF IMMUNOGLOBULIN REPLACEMENT THERAPY

Rituximab Associated Hypogammaglobulinemia in Autoimmune Disease.

ObjectiveTo evaluate the characteristics of patients with autoimmune disease with hypogammaglobulinemia following rituximab (RTX) and describe their long-term outcomes, including those who commenced immunoglobulin replacement therapy.MethodsPatients received RTX for autoimmune disease between 2003 and 2012 with immunoglobulin G (IgG) <7g/L were included in this retrospective series. Hypogammaglobulinemia was classified by nadir IgG subgroups of 5 to <7g/L (mild), 3 to <5g/L (moderate) and <3g/L (severe). Characteristics of patients were compared across subgroups and examined for factors associated with greater likelihood of long term hypogammaglobulinemia or immunoglobulin replacement.Results142 patients were included; 101 (71%) had anti-neutrophil cytoplasm antibody (ANCA) associated vasculitis (AAV), 18 (13%) systemic lupus erythematosus (SLE) and 23 (16%) other conditions. Mean follow-up was 97.2 months from first RTX. Hypogammaglobulinemia continued to be identified during long-term follow-up. Median time to IgG <5g/L was 22.5 months. Greater likelihood of moderate hypogammaglobulinemia (IgG <5g/L) and/or use of immunoglobulin replacement therapy at 60 months was observed in patients with prior cyclophosphamide exposure (odds ratio (OR) 3.60 [95% confidence interval (CI) 1.03 – 12.53], glucocorticoid use at 12 months [OR 7.48 (95% CI 1.28 – 43.55], lower nadir IgG within 12 months of RTX commencement [OR 0.68 (95% CI 0.51 – 0.90)] and female sex [OR 8.57 (95% CI 2.07 – 35.43)]. Immunoglobulin replacement was commenced in 29/142 (20%) and associated with reduction in infection rates, but not severe infection rates.ConclusionHypogammaglobulinemia continues to occur in long-term follow-up post-RTX. In patients with recurrent infections, immunoglobulin replacement reduced rates of non-severe infections.

Current Spectrum of Infections in Patients with X-Linked Agammaglobulinemia.

Outcome of patients with X-linked agammaglobulinemia (XLA) has improved with the widespread use of immunoglobulin replacement therapy (IgRT). There are few data on the spectrum of infections experienced by patients undergoing IgRT. We carried out a retrospective cross-sectional analysis of the records of XLA patients seen at Necker-Enfants Malades Hospital, Paris. For each infection, we evaluated infection site, microbial etiology, antibiotic prophylaxis, immunosuppressive treatment, IgRT route, and last known IgG trough level. Sixty patients were included, who cumulated a follow-up of 1470 patient-years. We recorded 188 infections, including 97 after initiation of IgRT. The rate of infection was highest before IgRT (0.66 vs. 0.06 per person-year (ppy), p < 0.001) and was higher after the age of 16 compared to before (0.14 vs. 0.05 ppy, p = 0.048). It was similar for patients receiving intravenous or subcutaneous Ig (0.09 vs 0.05 ppy, p = 0.54). The lungs and gastrointestinal tract accounted for 71% of infection sites. Forty-six (47%) infections occurred in patients receiving antibiotic prophylaxis. Sixteen (16.5%) infections occurred in patients receiving immunosuppressive therapy, which more frequently occurred after age 16 (35% vs. 2.4%, p < 0.001). The median IgG trough level prior to all infections was 8.4g/L. Almost half (44.3%) of infections occurred with prior IgG trough levels > 8g/L, and 16/97 (16.7%) in patients with trough levels > 10g/L. Infection remains a significant issue in patients with XLA undergoing IgRT despite adequate IgG trough levels. Chronic inflammatory manifestations of X-linked agammaglobulinemia and immunosuppressive therapies may be significant drivers of infection during adulthood.

Treating secondary antibody deficiency in patients with haematological malignancy: European expert consensus.

Secondary antibody deficiency (SAD), associated with severe, recurrent or persistent infections, is common in patients with haematological malignancies (HM), but unifying guidance on immunoglobulin replacement therapy (IgRT) in these patients is lacking. We aimed to develop consensus statements for the use of IgRT in patients with HM. A Delphi exercise was employed to test the level of agreement on statements developed by a Task Force based on available data and their clinical experience. In Round 1, an Expert Panel, comprising specialist EU physicians caring for patients with HM, helped to refine the statements. In Round 2, experts rated their agreement with the statements. In Round 3, experts who had scored their agreement as ≤4 were invited to review their agreement based on the overall feedback. Three definitions and 20 statements were formulated and tested for consensus, covering measurement of IgG levels, initiation and discontinuation of IgRT, dosing, and the use of subcutaneous IgG. Consensus (agreement ≥70% on Likert-type scale) was reached for all three definitions and 18 statements. Recommendations have been developed with the aim of providing guidance for the use of IgRT to prevent severe, recurrent or persistent infections in patients with HM and SAD.

PB2033 IMMUNOGLOBULIN REPLACEMENT THERAPY IN ADULT HEMATOLOGICAL PATIENTS: EFFECT ON THE INCIDENCE OF INFECTIOUS COMPLICATIONS

Background:The problem of infectious complications in hematology is determined by their high frequency, severity and difficulty of diagnosis. The clinical effect of immunoglobulin replacement therapy in relation to the risk of infectious complications in adult hematological patients currently needs to be assessed and revised.Aims:The aim of this prospective study was to evaluate the independent effect of immunoglobulin replacement therapy on the risk of developing infectious complications in hematological patients.Methods:The study included 34 adult patients receiving chemotherapy for hematological disease. Intervention groups (immunoglobulin replacement therapy) and the control group were matched by clinical and demographic characteristics. The primary outcome in the analysis was taken as the infection‐free period in the 180‐days survival analysis performed by Kaplan‐Meier with log‐rank test, Cox regression and Cox regression.Results:The average age of patients was 57.8 years, with sex distribution: 19 female and 15 male. Hematological diseases were distributed as follows: chronic lymphocytic leukemia ‐ 18, multiple myeloma ‐ 8, acute myeloid leukemia ‐ 2, acute lymphocytic leukemia ‐ 4, myelodysplastic syndrome ‐ 2. Among the included ‐ 15 patients had profound hypogammaglobulinemia (less than 4 g/l). Statistically significant association of immunoglobulin replacement therapy and reduction of the risk of infectious episodes was shown in a 180‐days period (log‐rank test, p = 0.037), Fig 1. The average duration of the period without infectious complications in the replacement group was 164 days (95% CI 147‐180 days), while in the control group it was 148 days (95% CI 124‐171 days). No additional confounding factors, which could cause the differences in the groups were found in the regression analysis (p = 0.035). The number needed to treat (NNT) was 3 patients (p = 0.018).Summary/Conclusion:The obtained data show that the use of immunoglobulin replacement therapy is independently associated with a longer period of infection‐free survival in adult hematological patients, what substantially improves the quality of life of such patients. The clinical effect may be assessed within 6 months from the start of immunoglobulin replacement therapy.image

Current clinical practice and challenges in the management of secondary immunodeficiency in hematological malignancies.

ObjectiveDespite long‐standing safe and effective use of immunoglobulin replacement therapy (IgRT) in primary immunodeficiency, clinical data on IgRT in patients with secondary immunodeficiency (SID) due to B‐cell lymphoproliferative diseases are limited. Here, we examine the correlation between approved IgRT indications, treatment recommendations, and clinical practice in SID.MethodsAn international online survey of 230 physicians responsible for the diagnosis of SID and the prescription of IgRT in patients with hematological malignancies was conducted.ResultsSerum immunoglobulin was measured in 83% of patients with multiple myeloma, 76% with chronic lymphocytic leukemia, and 69% with non‐Hodgkin lymphoma. Most physicians (85%) prescribed IgRT after ≥2 severe infections. In Italy, Germany, Spain, and the United States, immunoglobulin use was above average in patients with hypogammaglobulinemia, while in the UK considerably fewer patients received IgRT. The use of subcutaneous immunoglobulin was highest in France (34%) and lowest in Spain (19%). Immunologists measured specific antibody responses, performed test immunization, implemented IgRT, and used subcutaneous immunoglobulin more frequently than physicians overall.ConclusionsThe management of SID in hematological malignancies varied regionally. Clinical practice did not reflect treatment guidelines, highlighting the need for robust clinical studies on IgRT in this population and harmonization between countries and disciplines.

Immunoglobulin replacement for secondary immunodeficiency after B-cell targeted therapies in autoimmune rheumatic disease: Systematic literature review.

Consensus guidelines are not available for the use of immunoglobulin replacement therapy (IGRT) in patients developing iatrogenic secondary antibody deficiency following B-cell targeted therapy (BCTT) in autoimmune rheumatic disease. To evaluate the role of IGRT to manage hypogammaglobulinemia following BCTT in autoimmune rheumatic disease (AIRD). Using an agreed search string we performed a systematic literature search on Medline with Pubmed as vendor. We limited the search to English language papers with abstracts published over the last 10 years. Abstracts were screened for original data regarding hypogammaglobulinemia following BCTT and the use of IGRT for hypogammaglobulinemia following BCTT. We also searched current recommendations from national/international organisations including British Society for Rheumatology, UK Department of Health, American College of Rheumatology, and American Academy of Asthma, Allergy and Immunology. 222 abstracts were identified. Eight papers had original relevant data that met our search criteria. These studies were largely retrospective cohort studies with small patient numbers receiving IGRT. The literature highlights the induction of a sustained antibody deficiency, risk factors for hypogammaglobulinemia after BCTT including low baseline serum IgG levels, how to monitor patients for the development of hypogammaglobulinemia and the limited evidence available on intervention thresholds for commencing IGRT. The benefit of BCTT needs to be balanced against the risk of inducing a sustained secondary antibody deficiency. Consensus guidelines would be useful to enable appropriate assessment prior to and following BCTT in preventing and diagnosing hypogammaglobulinemia. Definitions for symptomatic hypogammaglobulinemia, intervention thresholds and treatment targets for IGRT, and its cost-effectiveness are required.

35-Year-Old Man With Episodic Fever and Cough

35-Year-Old Man With Episodic Fever and Cough

Dysregulation of Innate Lymphoid Cells in Common Variable Immunodeficiency.

Common variable immunodeficiency (CVID) is the most prevalent symptomatic primary immune deficiency. With widespread use of immunoglobulin replacement therapy, non-infectious complications, such as autoimmunity, chronic intestinal inflammation, and lung disease, have replaced infections as the major cause of morbidity and mortality in this immune deficiency. The pathogenic mechanisms that underlie the development of these complications in CVID are not known; however, there have been numerous associated laboratory findings. Among the most intriguing of these associations is elevation of interferon signature genes in CVID patients with inflammatory/autoimmune complications, as a similar gene expression profile is found in systemic lupus erythematosus and other chronic inflammatory diseases. Linked with this heightened interferon signature in CVID is an expansion of circulating IFN-γ-producing innate lymphoid cells. Innate lymphoid cells are key regulators of both protective and pathogenic immune responses that have been extensively studied in recent years. Further exploration of innate lymphoid cell biology in CVID may uncover key mechanisms underlying the development of inflammatory complications in these patients and may inspire much needed novel therapeutic approaches.

The Use of Salmonella Typhim Vaccine to Diagnose Antibody Deficiency.

The specific antibody response to the unconjugated 23-valent pneumococcal polysaccharide vaccine is one of the most common tests used to assess for possible humoral immunodeficiency. The results can be difficult to interpret because most people have been immunized with one or more of the pneumococcal vaccines and there is controversy regarding what constitutes a normal response. To circumvent this problem, we developed an ELISA to measure IgG-specific antibodies to the Salmonella Vi Typhim (S. Typhim) vaccine, a pure polysaccharide vaccine, which is a neoantigen for the vast majority of people in the USA. We compared the pre- and post-vaccination serum titers to the Vi Typhim vaccine in healthy controls (n=22), patients previously diagnosed with a primary immunodeficiency (n=30), and patients referred for possible humoral immune deficiency (n=29). We also determined if the S. Typhim vaccine could be used to assess specific antibody responses in people on antibody replacement therapy. Following immunization with the S. Typhim vaccine, we found that a 2-fold increase in titers is 100% sensitive and specific in detecting known humoral immune deficiencies as determined by ROC curve analysis. This cut-off value was successfully applied to possible immune deficiency patients (n=29), resulting in the diagnosis of seven subjects with humoral immunodeficiency. The use of immunoglobulin replacement therapy did not affect the median response ratios compared to subjects not receiving gammaglobulin. This study suggests that measurement of the specific antibody response to the S. Typhim vaccine may have advantages over pneumococcal vaccination in the evaluation of the humoral immune response.

Prophylactic immunoglobulin therapy in secondary immune deficiency – an expert opinion

ABSTRACTIntroduction: In primary immunodeficiency (PID), immunoglobulin replacement therapy (IgRT) for infection prevention is well-established and supported by a wealth of clinical data. On the contrary, very little evidence-based data is available on the challenges surrounding the use of IgRT in secondary immune deficiencies (SID), and most published guidelines are mere extrapolations from the experience in PID.Areas covered: In this article, four European experts provide their consolidated opinion on open questions surrounding the prophylactic use of IgRT in SID, based on their clinical experience. The main topics are IgRT initiation, route of administration, dose optimization, and therapy discontinuation. The authors hope this discussion will be of assistance to practicing physicians in their daily decision-making.Expert commentary: Although growing experience indicates that IgRT could play an important role in the management of SID, very little robust evidence is available to guide clinical practice. The authors stress the urgent need for new studies in the field and discuss points they find of importance to design them adequately.

Autoimmune and Lymphoproliferative Complications of Common Variable Immunodeficiency.

Common variable immunodeficiency (CVID) is frequently complicated by the development of autoimmune and lymphoproliferative diseases. With widespread use of immunoglobulin replacement therapy, autoimmune and lymphoproliferative complications have replaced infection as the major cause of morbidity and mortality in CVID patients. Certain CVID complications, such as bronchiectasis, are likely to be the result of immunodeficiency and are associated with infection susceptibility. However, other complications may result from immune dysregulation rather than immunocompromise. CVID patients develop autoimmunity, lymphoproliferation, and granulomas in association with distinct immunological abnormalities. Mutations in transmembrane activator and CAML interactor, reduction of isotype-switched memory B cells, expansion of CD21 low B cells, heightened interferon signature expression, and retained B cell function are all associated with both autoimmunity and lymphoproliferation in CVID. Further research aimed to better understand that the pathological mechanisms of these shared forms of immune dysregulation may inspire therapies beneficial for multiple CVID complications.