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

FLT3L governs the development of partially overlapping hematopoietic lineages in humans and mice

FMS-related tyrosine kinase 3 ligand (FLT3L), encoded by FLT3LG, is a hematopoietic factor essential for the development of natural killer (NK) cells, B cells, and dendritic cells (DCs) in mice. We describe three humans homozygous for a loss-of-function FLT3LG variant with a history of various recurrent infections, including severe cutaneous warts. The patients' bone marrow (BM) was hypoplastic, with low levels of hematopoietic progenitors, particularly myeloid and B cell precursors. Counts of B cells, monocytes, and DCs were low in the patients' blood, whereas the other blood subsets, including NK cells, were affected only moderately, if at all. The patients had normal counts of Langerhans cells (LCs) and dermal macrophages in the skin but lacked dermal DCs. Thus, FLT3L is required for B cell and DC development in mice and humans. However, unlike its murine counterpart, human FLT3L is required for the development of monocytes but not NK cells.

Relationships between bronchiectasis and time to achieving target trough immunoglobulin G levels in patients with common variable immunodeficiency

Background: The main treatment of common variable immunodeficiency (CVID) is to maintain immunoglobulin G (IgG) levels within the target range. However, trough IgG levels differ among patients with similar body mass index (BMI) and those receiving the same dose of immunoglobulin replacement therapy (IGRT). A crucial factor that underlies these differences is the presence of extensive bronchiectasis, which is associated with the immunoglobulin salvage pathway. Objective: We compared trough IgG levels in patients with CVID and with and in those without bronchiectasis who had received the same dose of IGRT for 2 years to determine the association of IgG level with infection frequency. Method: This retrospective cohort study included 61 patients with CVID, of whom 21 had bronchiectasis. We reviewed the electronic records for demographic variables, baseline immunoglobulin levels, mean trough IgG levels over 2 years, efficacy levels (trough IgG level - baseline IgG level), the time interval from treatment initiation to achieving the target trough IgG level (700 mg/dL), and the number of infections. Results: The median age of the patients was 39 years (IQR, 27-51), and 29 were women (47.5%). There were no significant differences between the groups in terms of age, age at diagnosis, delay in diagnosis, sex, BMI, IGRT type (subcutaneous or intravenous), and baseline immunoglobulin levels. Trough IgG and efficacy levels were lower (P < 0.001 and P = 0.016, respectively), the time required to achieve the target IgG level was longer in patients with bronchiectasis than in those without bronchiectasis, and this time interval was significantly associated with the infection frequency. Trough IgG and albumin levels were correlated (p = 0.007), with minor differences between the groups (p = 0.04). Conclusion: Bronchiectasis was significantly associated with a longer time to achieve the target IgG levels. These long-term differences between the patients with and those without bronchiectasis have significant clinical implications.

CVID-Associated Intestinal Disorders in the USIDNET Registry: An Analysis of Disease Manifestations, Functional Status, Comorbidities, and Treatment

Common variable immunodeficiency (CVID) has been subdivided into five phenotypes, including one marked by non-infectious enteropathies that lead to significant morbidity and mortality. We examined a large national registry of patients with CVID to better characterize this population and understand how the presence of enteropathy influences nutritional status, patient function, and the risk of additional non-infectious disorders in CVID patients. We also sought to illustrate the range of treatment strategies for CVID-associated enteropathies. We extracted patient data from the United States Immunodeficiency Network (USIDNET) database, which included 1415 patients with CVID, and compared those with and without intestinal disorders. Demographic and genetic profiles, functional status, and treatments targeting intestinal disorders are reported. Intestinal disorders were present in 20% of patients with CVID, including chronic diarrhea, inflammatory bowel disease, malabsorption, and others. Compared to those without enteropathies, this patient subset exhibited significantly lower Karnofsky-Lansky functional scores, greater reliance on nutritional support, higher rates of vitamin deficiencies, and increased prevalence of hematologic disorders, liver disease, pulmonary disease, granulomatous disease, and lymphoma. Genetic data were reported for only 5% of the cohort. No mutations segregated significantly to patients with or without intestinal disease. Corticosteroids were most frequently used for treatment. Patients with CVID-associated intestinal disorders exhibit higher rates of autoimmune and inflammatory comorbidities, lymphoma, malnutrition, and debility. We review recent studies implicating specific pathways underlying this immune dysregulation. Further studies are needed to evaluate the role of targeted immunomodulatory therapies for CVID-associated intestinal disorders.

CVID-associated intestinal disorders in the USIDNET registry: An analysis of disease manifestations, functional status, comorbidities, and treatment

Common variable immunodeficiency (CVID) has been subdivided into five phenotypes, including one marked by non-infectious enteropathies that lead to significant morbidity and mortality. We examined a large national registry of patients with CVID to better characterize this population and understand how the presence of enteropathy influences nutritional status, patient function, and the risk of additional non-infectious disorders in CVID patients. We also sought to illustrate the range of treatment strategies for CVID-associated enteropathies. We extracted patient data from the United States Immunodeficiency Network (USIDNET) database, which included 1415 patients with CVID, and compared those with and without intestinal disorders. Demographic and genetic profiles, functional status, and treatments targeting intestinal disorders are reported. Intestinal disorders were present in 20% of patients with CVID, including chronic diarrhea, inflammatory bowel disease, malabsorption, and others. Compared to those without enteropathies, this patient subset exhibited significantly lower Karnofsky-Lansky functional scores, greater reliance on nutritional support, higher rates of vitamin deficiencies, and increased prevalence of hematologic disorders, liver disease, pulmonary disease, granulomatous disease, and lymphoma. Genetic data were reported for only 5% of the cohort. No mutations segregated significantly to patients with or without intestinal disease. Corticosteroids were most frequently used for treatment. Patients with CVID-associated intestinal disorders exhibit higher rates of autoimmune and inflammatory comorbidities, lymphoma, malnutrition, and debility. We review recent studies implicating specific pathways underlying this immune dysregulation. Further studies are needed to evaluate the role of targeted immunomodulatory therapies for CVID-associated intestinal disorders.

Organ-based clues for diagnosis of inborn errors of immunity: A practical guide for clinicians

Inborn errors of immunity (IEI) comprise a group of about 490 genetic disorders that lead to aberrant functioning or the development of distinct immune system components. So far, a broad spectrum of IEI-related manifestations has been noted in the literature. Due to overlapping signs and symptoms of IEI, physicians face challenges in appropriately diagnosing and managing affected individuals. The last decade has witnesses improving in the molecular diagnosis of IEI patients. As a result, it can be the mainstay of diagnostic algorithms, prognosis, and possibly therapeutic interventions in patients with IEI. Furthermore, reviewing IEI clinical complications demonstrates that the manifestations and severity of the symptoms depend on the involved gene that causes the disease and its penetrance. Although several diagnostic criteria have been used for IEI, not every patient can be explored in the same way. As a result of the failure to consider IEI diagnosis and the variety of diagnostic capabilities and laboratory facilities in different regions, undiagnosed patients are increasing. On the other hand, early diagnosis is an almost essential element in improving the quality of life in IEI patients. Since there is no appropriate guideline for IEI diagnosis in different organs, focusing on the clues in the patient's chief complaint and physical exams can help physicians narrow their differential diagnosis. This article aims to provide a practical guide for IEI diagnosis based on the involved organ. We hope to assist clinicians in keeping IEI diagnosis in mind and minimizing possible related complications due to delayed diagnosis.

Clinical Outcome of Coronavirus Disease 2019 in Patients with Primary Antibody Deficiencies

In 2019, the novel coronavirus, SARS-CoV-2, caused a worldwide pandemic, affecting more than 630 million individuals and causing 6.5 million deaths. In the general population, poorer outcomes have been associated with older age, chronic lung and cardiovascular diseases, and lymphopenia, highlighting the important role of cellular immunity in the immune response against SARS-CoV-2. Moreover, SARS-CoV-2 variants may have a significant impact on disease severity. There is a significant overlap with complications commonly found in inborn errors of immunity (IEI), such as primary antibody deficiencies. The results of various studies have provided ambiguous findings. Several studies identified risk factors in the general population with a minor impact on SARS-CoV-2 infection. However, other studies have found a significant contribution of underlying immunodeficiency and immune-system dysregulation to the disease course. This ambiguity probably reflects the demographic differences and viral evolution. Impaired antibody production was associated with prolonged viral shedding, suggesting a critical role of humoral immunity in controlling SARS-CoV-2 infection. This may explain the poorer outcomes in primary antibody deficiencies compared to other IEIs. Understanding coronavirus disease 2019 (COVID-19) pathogenesis and identifying risk factors may help us identify patients at high risk of severe COVID-19 for whom preventive measures should be introduced.

Common variable immunodeficiency: different faces of the same disease

Introduction

Common variable immunodeficiency (CVID) is one of the primary humoral immunodeficiencies. Despite the inborn nature, the first symptoms may appear in both children and adults. It is characterized by hypogammaglobulinaemia, severe infections, autoimmunity, allergies, and a predisposition to cancer. A delay in diagnosis is a significant problem: the time from the first symptoms of the disease to diagnosis and the implementation of proper treatment is usually very long. The consequence can be irreversible complications, which is why it is so important to promote knowledge on this immunodeficiency.

Aim

To present the clinical and laboratory manifestation of primary immunodeficiencies such as common variable immunodeficiency.

Material and methods

The study presents the clinical and laboratory phenotype of 14 patients diagnosed with CVID, aged 5 to 58 years. A detailed medical history was taken, and clinical symptoms, immunological test results and complications were analysed in each patient. According to the ESID guidelines, in the differential diagnosis process of CVID the secondary hypogammaglobulinaemia was excluded.

Results

The follow-up period ranged from 39 to 133 months (median: 79 months). The median delay for the entire group was 5 years, which was shorter in children than in adults. In the presented group, the infectious phenotype (pneumonia, sinusitis) was dominant. Autoimmune and allergic diseases, malignant tumours and enteropathies have also been observed.

Conclusions

The diagnostic delay is still too long, especially in adults, which can lead to serious and irreversible complications. Early diagnosis and appropriate treatment with intravenous and subcutaneous immunoglobulins reduces the frequency of infections and their potential complications.

Common variable immunodeficiency disorders: What generalists should know

Primary immune deficiency disorders (PIDDs) are common and underdiagnosed. Predominant antibody deficiencies (PADs) are the most common type of immune deficiency and comprise 55% of the immune deficiencies diagnosed.^[1] Although immunoglobulin A (IgA) deficiency remains the most common type of PID, common variable immunodeficiency disorders remain the most common symptomatic PID for which medical therapy is sought.

Acute abdomen in the immunocompromised patient: WSES, SIS-E, WSIS, AAST, and GAIS guidelines

Immunocompromised patients are a heterogeneous and diffuse category frequently presenting to the emergency department with acute surgical diseases. Diagnosis and treatment in immunocompromised patients are often complex and must be multidisciplinary. Misdiagnosis of an acute surgical disease may be followed by increased morbidity and mortality. Delayed diagnosis and treatment of surgical disease occur; these patients may seek medical assistance late because their symptoms are often ambiguous. Also, they develop unique surgical problems that do not affect the general population. Management of this population must be multidisciplinary.This paper presents the World Society of Emergency Surgery (WSES), Surgical Infection Society Europe (SIS-E), World Surgical Infection Society (WSIS), American Association for the Surgery of Trauma (AAST), and Global Alliance for Infection in Surgery (GAIS) joined guidelines about the management of acute abdomen in immunocompromised patients.

Immune-mediated enteropathies: From bench to bedside

Immune-mediated enteropathies are caused by excessive reactions of the intestinal immune system towards non-pathogenic molecules. Enteropathy leads to malabsorption-related symptoms and include (severe) chronic diarrhea, weight loss and vitamin deficiencies. Parenteral feeding and immunosuppressive therapy are needed in severe cases. Celiac disease has long been recognized as the most common immune-mediated enteropathy in adults, but the spectrum of immune-mediated enteropathies has been expanding. Histological and clinical features are sometimes shared among these enteropathies, and therefore it may be challenging to differentiate between them. Here, we provide an overview of immune-mediated enteropathies focused on clinical presentation, establishing diagnosis, immunopathogenesis, and treatment options.

Rapid clinical recovery of a SARS-CoV-2 infected common variable immunodeficiency patient following the infusion of COVID-19 convalescent plasma

Background

Common variable immunodeficiency is the most prevalent symptomatic primary immunodeficiency in adults. Affected patients fail to mount an appropriate humoral response against community acquired infectious diseases and recent reports have provided data supporting the increased susceptibility of these patients to severe SARS-CoV-2 infections. In this context, the infusion of COVID-19 convalescent plasma could represent an effective therapeutic strategy.

Case presentation

25-year old woman diagnosed with common variable immunodeficiency in 2013, developed severe COVID-19 that rapidly progressed to pneumonia presenting with multiple bilateral lung opacities that were both central and peripheral and presented as ground-glass and consolidation types involving all lobes, bilaterally. As blood oxygen saturation decayed and lung abnormalities were not responsive to large spectrum antibiotics and corticosteroids, patient was placed on mechanical ventilation and compassionate-use of approved COVID-19 convalescent donor plasma was introduced. The patient presented a rapid response to the approach and mechanical ventilation could be interrupted 24 h after first dose of COVID-19 convalescent donor plasma. As a whole, the patient received four doses of 200 mL convalescent plasma during a period of 6 days. There was rapid improvement of clinical status, with interruption of supplemental oxygen therapy after 6 days and reduction of lung abnormalities as evidence by sequential computed tomography scans.

Conclusions

This is a single patient report that adds to other few reports on common variable immunodeficiency and agammaglobulinemia, suggesting that COVID-19 convalescent donor plasma could be a valuable therapeutic approach to treat patients affected by dysgammaglobulinemias and presenting severe COVID-19.

Chronic urticaria and common variable immunodeficiency (CVID): an association to remember

The patient is a 64-year-old Caucasian woman with idiopathic chronic urticaria who presented to her primary care physician's office with mucoid otitis media. Medical history was significant for hypertension, hyperlipidaemia, allergic rhinitis, pre-diabetes, gastro-oesophageal reflux, paroxysmal atrial fibrillation, chronic kidney disease, diverticulosis with prior diverticulitis and history of recurrent infections. Her chronic urticaria was initially treated with antibiotics, antihistamines and oral steroids, but later she developed refractory urticaria requiring dapsone with modest improvement. When she presented with mucoid otitis media, immunoglobulin levels were found to be decreased. The pneumococcal vaccine antibody challenge confirmed the diagnosis of common variable immunodeficiency (CVID). Her HIV test was negative. She was started on intravenous immunoglobulin infusions and her chronic urticaria stabilised.In patients with chronic urticaria refractory to treatment, especially with a history of recurrent infections, a diagnosis of CVID should be considered, regardless of HIV status.

Variable immunodeficiency study: Evaluation of two European cohorts within a variety of clinical phenotypes

INTRODUCTION

Given the wide heterogeneity of common variable immunodeficiency (CVID), several groups have proposed clinical and immunological classifications to better define follow-up and prognostic algorithms. The present study aims to validate recent clinical and laboratory algorithms, based on different combinations of CVID biomarkers, to provide more personalized treatment and follow-up strategies.

METHODS

We analysed clinical and immunological features of 80 patients with suspected or diagnosed CVID, in two reference centres of Portugal and Spain. Clinical manifestations were categorized into clinical phenotyping proposed by Chapel et al. [1] that included cytopenia; polyclonal lymphocytic infiltration; unexplained enteropathy; and no disease-related complications.

RESULTS

76% of patients in our cohort entered one of the four categories of clinical phenotyping, without overlap (cytopenia; polyclonal lymphocytic infiltration; unexplained enteropathy; and no disease-related complications). The most prominent phenotype was "cytopenia" (40%) followed by "polyclonal lymphocytic infiltration" (19%). The remaining 24% patients of our cohort had overlap of 2 clinical phenotypes (cytopenia and unexplained enteropathy mainly). A delay of CVID diagnosis in more than 6 years presented 3.7-fold higher risk of developing lymphoproliferation and/or malignancy (p < 0.05), and was associated with increased CD8⁺CD45RO ⁺ T-lymphocytes (p < 0.05). An association between decreased switched-memory B cells with lymphoproliferation and malignancy was observed (p < 0.03 and p < 0.05, respectively). CD4 ⁺ T-lymphocytopenia correlated with autoimmune phenotype, with 30% prevalence (p < 0.05). HLA-DR7 expression was related to CVID onset in early life in our patients (13 vs 25 years), and DQ2.5 or DQ2.2 with unexplained enteropathy (p < 0.05).

CONCLUSIONS

The phenotypic and genetic study is crucial for an adequate clinical orientation of CVID patients. In these two independent cohorts of patients, classification based in clinical and laboratory algorithms, provides more personalized treatment and follow-up strategies.

Alpha-1 Antitrypsin Deficiency and Pulmonary Morbidity in Patients with Primary Immunodeficiency Disease: A Single-Center Experience

Background

Alpha-1 antitrypsin deficiency (AATD) is of importance in the pathogenesis of pulmonary emphysema, chronic obstructive pulmonary diseases (COPD), and bronchiectasis. Various pulmonary disorders are a typical feature of primary immunodeficiency disease (PID). This includes recurrent pulmonary infections, immunodysregulation, and autoinflammatory diseases. As a result, incidence of acute and chronic pulmonary diseases is higher. Interestingly, pulmonary morbidity in PID and AATD share similar features. To study the coexistence of AATD in patients suffering from PID, we performed the underlying investigation.

Methods

We evaluated a study group of 149 patients (n = 149) with PID. In total, serum AAT concentrations were available for 110 patients (n = 110). For the identified patients, we analyzed both clinical associations and interactions.

Results

Among the investigated patients, reduced serum AAT levels were detected in 7 patients. With regard to the genotype, PI∗ZZ was found in 2 patients, whereas PI∗MZ was observed in 5 patients. Independent of the underlying phenotype, obstructive lung diseases were found in 2 patients with PI∗ZZ and 2 patients with PI∗MZ.

Conclusions

In Germany, the estimated percentage for PI∗ZZ and PI∗MZ is 0.01% and 1.9%, respectively. As demonstrated, the ratio in our study group was even higher. We identified seven patients with AATD. Since AATD contributes to pulmonary morbidity in PID patients, systematic underdiagnosis of the coexistence might yield a strong clinical impact. Hence, AAT analysis should be offered to all patients with confirmed PID diagnoses. To strengthen this finding, we suggest the investigation of larger databases.

Autoimmune Lymphoproliferative Syndrome: An Overview

Autoimmune lymphoproliferative syndrome (ALPS) is an inherited nonmalignant lymphoproliferative disorder characterized by heterozygous mutations within the first apoptosis signal receptor (FAS) signaling pathway. Defects in FAS-mediated apoptosis cause an expansion and accumulation of autoreactive CD4- and CD8- (double-negative) T cells, leading to cytopenias, splenomegaly, lymphadenopathy, autoimmune disorders, and a greatly increased lifetime risk of lymphoma. The differential diagnosis of ALPS includes infection, other inherited immunodeficiency disorders, primary and secondary autoimmune syndromes, and lymphoma. The most consistent pathologic feature is a florid paracortical expansion of double-negative T cells in lymph nodes. A presumptive clinical diagnosis can be made from symptoms and a constellation of laboratory test results. However, a definitive diagnosis requires ancillary testing and enables disease subclassification. Recognition of ALPS is critical, as treatment with immunosuppressive therapies can effectively reduce or ameliorate symptoms for most patients.

Comprehensive assessment of respiratory complications in patients with common variable immunodeficiency

BACKGROUND

Common variable immunodeficiency (CVID) is a heterogeneous group of disorders, characterized by recurrent upper and lower respiratory tract infections and some noninfectious clinical complications.

OBJECTIVE

To provide a detailed evaluation of respiratory presentations and complications in a cohort of Iranian patients with CVID.

METHODS

A retrospective cohort study was conducted on 245 CVID patients who were recorded in the Iranian primary immunodeficiency disorders registry network. Respiratory manifestations were evaluated by reviewing clinical hospital records, immunologic findings, pulmonary function tests (PFT), and high-resolution computed tomography (HRCT) scans.

RESULTS

Most of the patients (n = 208, 85.2%) had experienced at least 1 episode of acute respiratory manifestation, and pneumonia was observed in 31.6 % (n = 77) of cases as a first disease manifestation. During the follow-up, pneumonia, sinusitis, and otitis media were documented in 166 (68.6%), 125 (51.2%), and 103 (42.6%) cases, respectively. Abnormal PFT measurements were documented in 53.8% of patients. Among these patients, 21.5% showed restrictive changes, whereas 18.4% of patients showed an obstructive pattern. Bronchiectasis was the most frequent radiological finding, confirmed in 27.2% of patients. Patients with bronchiectasis were older at the time of immunodeficiency diagnosis (P < .001) and had longer diagnosis delay (P < .001) when compared with patients without bronchiectasis.

CONCLUSION

This study highlights the importance of monitoring the respiratory tract system even in asymptomatic patients. Pulmonary function tests and CT scans are the most commonly used techniques aiming to identify these patients early, aiming to reduce the rate of long-term respiratory complications.

Lymphocyte Subset Abnormalities in Pediatric-Onset Common Variable Immunodeficiency

INTRODUCTION

Common variable immunodeficiency (CVID) is characterized by recurrent infections, autoimmunity, lymphoproliferation, hypogammaglobulinemia, and defective antibody production. In CVID, B-cell abnormalities were described to predict end organ involvement and prognosis. Pediatric-onset CVID is much rarer than adult CVID, and lymphocyte subset abnormalities have not been thoroughly evaluated.

OBJECTIVE

We sought to determine lymphocyte subset abnormalities and their association with end organ involvement in pediatric-onset CVID patients.

METHODS

The clinical manifestations and laboratory findings including absolute numbers and percentages of B-, T-, and NK cell populations were assessed in pediatric-onset CVID patients and compared to age-matched healthy controls. The patients were divided into 2 groups according to age at assessment (pediatric CVID patients: 10-16 years, n = 9; and adult CVID patients: >16 years, n = 13). The comparisons between lymphocyte subsets and organ involvement were also evaluated.

RESULTS

Mean age at symptom onset was 18 (3-204) months. All CVID patients with pediatric onset had decreased levels of total and memory B cells, CD4+ T cells, CD4+CD45RA+ naive T cells, and recent thymic emigrant (RTE) cells. On the other hand, they had increases in CD8+CD45RO+ memory T cells. Interestingly, adult CVID patients demonstrated high frequencies of activated and double-negative T cells, which were unique only for this group of patients. Specific cellular abnormalities associated with the reduction in B and NK cells and increase in CD8+ T cells were found in patients with bronchiectasis. Moreover, in pediatric CVID patients, low serum IgA levels and decreased numbers of naive T and RTE cells were determined as risk factors for chronic diarrhea.

CONCLUSIONS

Specific abnormalities in B- and T-lymphocyte compartments were identified in pediatric-onset CVID patients and appear to be associated with end organ manifestations.

Recurrent Sinopulmonary Infections in a Patient Whose HIV Masked Common Variable Immunodeficiency

It is generally accepted that persons infected with human immunodeficiency virus (HIV) are at an increased risk of infection due to direct destruction of CD4⁺ lymphocytes and subsequently impaired cell-mediated immunity. Typically, HIV infection is associated with immunoglobulin elevations, but quantitative deficiencies in immunoglobulins have also been rarely described. We present an unusual case of common variable immunodeficiency (CVID) in a HIV-positive patient with recurrent severe respiratory infections. We review epidemiology, clinical presentation, and treatment of primary immunoglobulin deficiency. We also review the relationship between immunoglobulin deficiency and HIV and highlight the importance of recognizing the coexistence of two distinct immunodeficiency syndromes.

Acute Cervical Longitudinally Extensive Transverse Myelitis in a Child With Lipopolysaccharide-Responsive-Beige-Like-Anchor-Protein (LRBA) Deficiency: A New Complication of a Rare Disease

Lipopolysaccharide responsive beige-like anchor protein (LRBA) deficiency is a primary immunodeficiency disorder (PID) that can cause a common variable immunodeficiency (CVID)-like disease. The typical features of the disease are autoimmunity, chronic diarrhea, and hypogammaglobulinemia. Neurological complications are also reported in patients affected by LRBA deficiency. We describe a 7-year old female with an acute cervical longitudinally extensive transverse myelitis (LETM) as a feature of LRBA deficiency. This is the first case of LETM associated with LRBA deficiency described in literature.

Focus on Chronic Variable Immunodeficiency for Primary Care Practitioners, the Gatekeepers to Optimal Health Outcomes for Primary Immunodeficiency Syndromes

Purpose of Review

This review sought to assess the extent and causes of suboptimal healthcare outcomes for chronic variable immunodeficiency (CVID).

Recent Findings

Significant improvements in diagnostic technology and treatment protocols over time were found, leading to reduced morbidity and mortality for those accessing therapies. Treatments continue to be largely non-curative with financing (mainly insurance coverage) an obstacle. Symptom recognition by primary care practitioners (PCP) remains a gating factor to treatment and a widespread and persistent barrier to optimal health outcomes.

Summary

CVID is a subtype of primary immunodeficiency (PIDD) associated with under-diagnosis. It has emerged as a health issue more prevalent than historically known. No symptom-recognition framework for early detection of CVID has been generally accepted; those proposed for primary immunodeficiencies have shown low sensitivity, low specificity or both. Positive trends in cases diagnosed have been aided by awareness campaigns and international collaborations. However, treatments for CVID will not realize full potential without effective, accepted frameworks for timely identification in the clinic.

The Expanding Field of Secondary Antibody Deficiency: Causes, Diagnosis, and Management

Antibody deficiency or hypogammaglobulinemia can have primary or secondary etiologies. Primary antibody deficiency (PAD) is the result of intrinsic genetic defects, whereas secondary antibody deficiency may arise as a consequence of underlying conditions or medication use. On a global level, malnutrition, HIV, and malaria are major causes of secondary immunodeficiency. In this review we consider secondary antibody deficiency, for which common causes include hematological malignancies, such as chronic lymphocytic leukemia or multiple myeloma, and their treatment, protein-losing states, and side effects of a number of immunosuppressive agents and procedures involved in solid organ transplantation. Secondary antibody deficiency is not only much more common than PAD, but is also being increasingly recognized with the wider and more prolonged use of a growing list of agents targeting B cells. SAD may thus present to a broad range of specialties and is associated with an increased risk of infection. Early diagnosis and intervention is key to avoiding morbidity and mortality. Optimizing treatment requires careful clinical and laboratory assessment and may involve close monitoring of risk parameters, vaccination, antibiotic strategies, and in some patients, immunoglobulin replacement therapy (IgRT). This review discusses the rapidly evolving list of underlying causes of secondary antibody deficiency, specifically focusing on therapies targeting B cells, alongside recent advances in screening, biomarkers of risk for the development of secondary antibody deficiency, diagnosis, monitoring, and management.

Indian Antimicrobial Prescription Guidelines in Critically Ill Immunocompromised Patients

How to cite this article: Kulkarni AP, Sengar M, Chinnaswamy G, Hegde A, Rodrigues C, Soman R, Khilnani GC, Ramasubban S, Desai M, Pandit R, Khasne R, Shetty A, Gilada T, Bhosale S, Kothekar A, Dixit S, Zirpe K, Mehta Y, Pulinilkunnathil JG, Bhagat V, Khan MS, Narkhede AM, Baliga N, Ammapalli S, Bamne S, Turkar S, Bhat KV, Choudhary J, Kumar R, Divatia JV. Indian Journal of Critical Care Medicine 2019;23(Suppl 1): S64-S96.

Are naïve T cells and class-switched memory (IgD- CD27+) B cells not essential for establishment and maintenance of pregnancy? Insights from a case of common variable immunodeficiency with pregnancy

The disruption of adaptive immune response has adverse effects on the establishment and maintenance of pregnancy. The adaptive immune system is regulated by several types of immune cells. However, there is limited information about cell hierarchy in the adaptive immune response to the establishment and maintenance of pregnancy in women. The assessment of the outcome of pregnancy in primary immunodeficiency diseases could help in understanding the cell hierarchy in the adaptive immune system during pregnancy. Common variable immunodeficiency (CVID) is a heterogeneous adaptive immune system disorder characterized by primary hypogammaglobulinemia. A few studies have previously reported the assessment of the T and B cell subpopulations in CVID patients. However, an assessment of the subpopulations of T and B cells and the outcome of pregnancy in women with CVID has not been reported till date. Most CVID patients show a general decrease in the expression of CD27 in B cells. The assessment of pregnancy and the subpopulations of T and B cells in CVID women with severe reduction in the naïve T and switched B cells could help understand whether these cells are essential for the establishment and maintenance of pregnancy in women.

Case Report of Acquired Generalized Lipodystrophy Associated With Common Variable Immunodeficiency

CONTEXT

Acquired generalized lipodystrophy (AGL), a rare disorder characterized by loss of subcutaneous adipose tissue, is estimated to occur in association with autoimmune diseases in ~25% of the cases. Common variable immunodeficiency (CVI) is a condition known for its strong association with autoimmune diseases often occurring with negative autoantibodies. To the best of our knowledge, we describe the first known case of AGL in a patient with CVI.

CASE DESCRIPTION

A 24-year-old man was referred to our center with hyperglycemia, hypertriglyceridemia, hepatomegaly, and a clear pattern of generalized fat loss. AGL had been diagnosed on the basis of the clinical and laboratory findings. Because of the presence of associated hypogammaglobulinemia, a diagnosis of CVI was subsequently established.

CONCLUSIONS

We propose that AGL be added to the list of possible diseases associated with CVI and, owing to the similar clinical presentation with type 1 diabetes mellitus, be included in the differential diagnosis of this condition, which is present in 1.5% of patients with CVI.

Intravenous immunoglobulin replacement treatment reduces in vivo elastase secretion in patients with common variable immune disorders

BACKGROUND

Intravenous immunoglobulin (IVIg) treatment partially replaces antibody defects and modulates innate and adaptive immune cells in patients with primary antibody deficiencies.

MATERIALS AND METHODS

This study was focused on the evaluation of the effects of in vivo IVIg administration on neutrophils from patients with common variable immune disorders (CVID). We examined polymorphonuclear neutrophil (PMN) phagocytosis, PMN oxidative burst, release of neutrophil elastase, serum level of interleukin-8 and PMN expression of CXCR1, CD11c and CD66b.

RESULTS

CVID patients on chronic IVIg treatment had reduced elastase release, but normal expression of CXCR1, CD66b and CD11c receptors on PMN, normal phagocytic ability and normal secretion of interleukin-8. We found that IVIg infusions rapidly reduced the serum level of interleukin-8, the expression of its receptor, CXCR1, and the release of neutrophil elastase, suggesting that IVIg exert a dampening effect on neutrophil activity. In contrast, IVIg infusions did not alter neutrophil phagocytosis or the expression of the other receptors analysed.

DISCUSSION

These findings add further information regarding the anti-inflammatory role of immunoglobulins and suggest additional benefits in keeping with recent attempts to use new therapies targeting neutrophil inflammation.

Effectiveness of immunoglobulin prophylaxis in reducing clinical complications of hematopoietic stem cell transplantation: a systematic review and meta-analysis

BACKGROUND

Prophylactic immunoglobulin has been used with varying efficacy to reduce complications in hematopoietic stem cell transplant recipients.

STUDY DESIGN AND METHODS

A systematic review and meta-analysis was conducted of randomized controlled trials that assessed clinical outcomes (overall survival, transplant-related mortality, graft-versus-host disease [GVHD], veno-occlusive disease [VOD], interstitial pneumonitis, disease relapse, cytomegalovirus [CMV] infection and disease, non-CMV infection) of immunoglobulin prophylaxis versus placebo in hematopoietic stem cell transplant recipients. MEDLINE, EMBASE, EBM Reviews, and the Cochrane Central Register of Controlled Trials were searched up to June 2017. Quality of included studies and outcomes were evaluated via Risk of Bias assessment and Grading of Recommendations, Assessment, Development and Evaluation criteria, respectively.

RESULTS

Of 899 citations screened, 27 studies (n = 3934) were included. Immunoglobulin prophylaxis had no impact on survival (risk ratio [RR], 0.94; 95% confidence interval [CI], 0.88-1.01; 11 studies, n = 1962) but decreased risk of acute GVHD (RR, 0.78; 95% CI, 0.65-0.94; eight studies, n = 1097) and CMV disease (RR, 0.52; 95% CI, 0.28-0.97; two studies, n = 167). Meta-analysis revealed increased risk of VOD (RR, 3.04; 95% CI, 1.10-8.41; three studies, n = 384) and disease relapse (RR, 1.26; 95% CI, 1.07-1.49; seven studies, n = 1647). Other outcomes were small in sample size or nonsignificant. Results should be interpreted cautiously given the low quality of studies and evidence of outcomes.

CONCLUSION

Immunoglobulin prophylaxis did not have a significant effect on survival. Positive clinical effects were shown for acute GVHD and CMV disease and negative effects against VOD and disease relapse. No studies examined the effect of immunoglobulin treatment in hypogammaglobulinemic patients despite current guidelines, warranting further studies in this population.

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.

Evans Syndrome as First Manifestation of Primary Immunodeficiency in Clinical Practice

BACKGROUND

Evans syndrome (ES) is a rare immune disorder in children, manifested by simultaneous or sequential autoimmune cytopenias (ACs) of unknown cause and having a chronic course with periods of exacerbation and remission. Some primary immunodeficiencies (PIDs) may present with autoimmune manifestations without infections, masking suspicion of them. The PIDs that can typically manifest as ES are autoimmune lymphoproliferative syndrome and common variable immunodeficiency (CVID).

MATERIALS AND METHODS

Review of clinical charts and laboratory results of pediatric patients followed-up in the outpatient clinic of PID with a diagnosis of ES and humoral immunodeficiency.

RESULTS

Three pediatric patients, a boy and 2 girls, presented with corticosteroid-dependent ES. In the diagnostic approach, autoimmune lymphoproliferative syndrome was ruled out, and during follow-up, patients showed laboratory signs of humoral immune deficiency and were diagnosed with CVID. After initiating the recommended treatment for CVID with AC, patients improved without new exacerbations.

CONCLUSIONS

These cases highlight the importance of detection of possible PID in the context of ES and the establishment of CVID treatment to control AC.

Chronic lung disease in common variable immune deficiency (CVID): A pathophysiological role for microbial and non-B cell immune factors

One of the most common and most severe forms of primary antibody deficiency encountered in the clinical setting is a heterogeneous group of syndromes termed common variable immune deficiency (CVID). This disorder is characterized by reduced immunoglobulin production and increased susceptibility to infection, particularly of the respiratory tract. Infection and subsequent immunological/inflammatory processes may contribute to the development of pulmonary complications such as bronchiectasis and interstitial lung disease. Immunoglobulin replacement and/or antibiotic therapy, to prevent infection, are routinely prescribed treatments. However, chronic lung disease, the major cause of morbidity and mortality in this patient cohort, may still progress. This clinical progression suggests that pathogens recalcitrant to currently prescribed treatments and other immunological defects may be contributing to the development of pulmonary disease. This review describes the potential role of microbiological and non-B cell immunological factors, including T-cells, neutrophils, complement, toll like receptors, and antimicrobial peptides, in the pathogenicity of chronic lung disease in patients with CVID.

Management of common variable immunodeficiency by subcutaneous IgG self-administration during pregnancy - a case report

Patients with common variable immunodeficiency are prone to infections, and this poses a particular challenge during pregnancy, when the requirement for immunoglobulin (Ig) replacement therapy is even more demanding so as to achieve an effective protection also of the fetus. This case report highlights the benefits observed with subcutaneous IgG self‐administration in the management of common variable immunodeficiency (CVID) during pregnancy, in terms of efficacy and safety.

Humoral primary immunodeficiency diseases: clinical overview and chest high-resolution computed tomography (HRCT) features in the adult population

Humoral primary immunodeficiency diseases (hPIDs) are a heterogeneous group of hereditary disorders resulting in abnormal susceptibility to infections of the sinopulmonary tract. Some of these conditions (e.g., common variable immunodeficiency disorders [CVID]) imply a number of non-infectious thoracic complications such as non-infectious airway disorders, diffuse lung parenchymal diseases, and neoplasms. Chest high-resolution computed tomography (HRCT) is a key imaging tool to characterise and quantify the extent of underlying thoracic involvement, as well as to direct and monitor treatment. The aims of this review are to provide a brief clinical overview of hPIDs and describe the related chest HRCT imaging features in the adult population, with a special focus on CVID and its complications.

Approach to the Management of Autoimmunity in Primary Immunodeficiency

Primary immunodeficiency diseases (PIDs) consist of a genetically heterogeneous group of immune disorders that affect distinct elements of the immune system. PID patients are more prone to infections and non-infectious complications, particularly autoimmunity. The concomitance of immunodeficiency and autoimmunity appears to be paradoxical and leads to difficulty in the management of autoimmune complications in PID patients. Therefore, management of autoimmunity in patients with PID requires special considerations because dysregulations and dysfunctions of the immune system along with persistent inflammation impair the process of diagnosis and treatment.

Lymphocytic duodenitis or microscopic enteritis and gluten-related conditions: what needs to be explored?

Microscopic enteritis (ME) is characterized by abnormal infiltration of intraepithelial lymphocytes in intestinal mucosa. It was described as duodenal lymphocytosis or lymphocytic duodenitis until the dedicated Consensus Conference of 2015. ME represents a common feature of several gluten-mediated and non-gluten related diseases; therefore, it is an umbrella term embracing several conditions. The most frequent causes of ME are gluten-related disorders (celiac disease, non-celiac gluten sensitivity, wheat allergy), Helicobacter pylori infection and drug-related damages. Less frequently, ME may be secondary to inflammatory bowel disease, some autoimmune conditions, immunoglobulin deficiencies, blood malignancies, infections and irritable bowel syndrome. Therefore, the differential diagnosis of ME may be challenging. The diagnosis of ME needs to be driven by predominant symptoms and patient history. However, it is often difficult to achieve an immediate identification of the underlying condition, and a broad variety of diagnostic tests may be required. Ultimately, long-term surveillance is needed for a final diagnosis in many cases, since a hidden or quiescent condition may be disclosed after a period of latency. In any case, strict collaboration between the clinician and the pathologist is pivotal. The treatment of ME should be personalized, depending on the underlying disease. For gluten-related conditions (celiac disease, gluten sensitivity, wheat allergy, dermatitis herpetiformis), a gluten-free diet may be proposed. For other conditions, a targeted etiologic treatment is necessary. In conclusion, ME represents a novel entity that is attracting increasing interest. The growing epidemiologic trend confirms that it will become a common condition in clinical practice.

Intravenous immunoglobulin replacement treatment does not alter polymorphonuclear leukocytes function and surface receptors expression in patients with common variable immunodeficiency

The study of the expression of CD16, CD11b and Siglec 9 receptors and the oxidative burst provides insights on polymorphonuclear leukocytes (PMN) functionality in common variable immunodeficiency (CVID) and on the possible effects of intravenous immunoglobulin (IVIg) infusion. We evaluated in vivo before and soon after IVIg administration the CD16, CD11b and Siglec 9 expression on unstimulated and Escherichia coli-stimulated PMN and the oxidative burst induced by Escherichia coli and PMA. The E. coli stimulation up-regulated CD16 and Siglec 9 expression and it induced a strong CD11b up-regulation at baseline and soon after IVIg. The oxidative burst overlapped that observed in healthy donors when induced by Escherichia coli while it increased when induced by PMA. Soon after IVIg infusion, the oxidative burst decreased only when induced by PMA. Our results showed that the IVIg infusion in vivo had a minimal effect on CVID's PMN.

Successful Hematopoietic Stem Cell Transplantation in a Patient with LPS-Responsive Beige-Like Anchor (LRBA) Gene Mutation

PURPOSE

Autosomal recessive mutations in LRBA, encoding for LPS-responsive beige-like anchor protein, were described in patients with a common variable immunodeficiency (CVID)-like disease characterized by hypogammaglobulinemia, autoimmune cytopenias, and enteropathy. Here, we detail the clinical, immunological, and genetic features of a patient with severe autoimmune manifestations.

METHODS

Whole exome sequencing was performed to establish a molecular diagnosis. Evaluation of lymphocyte subsets was performed for immunological characterization. Medical files were reviewed to collect clinical and immunological data.

RESULTS

A 7-year-old boy, born to consanguineous parents, presented with autoimmune hemolytic anemia, hepatosplenomegaly, autoimmune thyroiditis, and severe autoimmune gastrointestinal manifestations. Immunological investigations revealed low immunoglobulin levels and low numbers of B and NK cells. Treatment included immunoglobulin replacement and immunosuppressive therapy. Seven years after disease onset, the patient developed severe neurological symptoms resembling acute disseminated encephalomyelitis, prompting allogeneic hematopoietic stem cell transplantation (HSCT) with the HLA-identical mother as donor. Whole exome sequencing of the patient uncovered a homozygous 1 bp deletion in LRBA (c.7162delA:p.T2388Pfs*7). Importantly, during 2 years of follow-up post-HSCT, marked clinical improvement and recovery of immune function was observed.

CONCLUSIONS

Our data suggest a beneficial effect of HSCT in patients with LRBA deficiency.

Mechanisms and management of refractory coeliac disease

A small subset of patients with coeliac disease become refractory to a gluten-free diet with persistent malabsorption and intestinal villous atrophy. The most common cause of this condition is inadvertent gluten exposure, but concomitant diseases leading to villous atrophy should also be considered and excluded. After exclusion of these conditions, patients are referred to as having refractory coeliac disease, of which two categories are recognized based on the absence (type I) or presence (type II) of a clonal expansion of premalignant intraepithelial lymphocyte population with a high potential for transformation into an overt enteropathy-associated T-cell lymphoma. Type I disease usually has a benign course that can be controlled by mild immunosuppressive treatment, but type II can be more severe with cladribine with or without autologous stem cell transplantation effective as treatment. Patients who fail to respond to cladribine therapy, however, still have a high risk of malignant transformation. Insights into the immunophenotype of these cells and the recognition that type II disease is a low-grade, no-mass lymphoma opens avenues for new treatment strategies, including chemotherapeutic and immunomodulating strategies. This Review will provide an overview of refractory coeliac disease, discussing mechanisms, diagnosis and management.

Seronegative Celiac Disease and Immunoglobulin Deficiency: Where to Look in the Submerged Iceberg?

In the present narrative review, we analyzed the relationship between seronegative celiac disease (SNCD) and immunoglobulin deficiencies. For this purpose, we conducted a literature search on the main medical databases. SNCD poses a diagnostic dilemma. Villous blunting, intraepithelial lymphocytes (IELs) count and gluten "challenge" are the most reliable markers. Immunohistochemistry/immunofluorescence tissue transglutaminase (tTG)-targeted mucosal immunoglobulin A (IgA) immune complexes in the intestinal mucosa of SNCD patients may be useful. In our experience, tTG-mRNA was similarly increased in seropositive celiac disease (CD) and suspected SNCD, and strongly correlated with the IELs count. This increase is found even in the IELs' range of 15-25/100 enterocytes, suggesting that there may be a "grey zone" of gluten-related disorders. An immune deregulation (severely lacking B-cell differentiation) underlies the association of SNCD with immunoglobulin deficiencies. Therefore, CD may be linked to autoimmune disorders and immune deficits (common variable immunodeficiency (CVID)/IgA selective deficiency). CVID is a heterogeneous group of antibodies dysfunction, whose association with CD is demonstrated only by the response to a gluten-free diet (GFD). We hypothesized a familial inheritance between CD and CVID. Selective IgA deficiency, commonly associated with CD, accounts for IgA-tTG seronegativity. Selective IgM deficiency (sIgMD) is rare (<300 cases) and associated to CD in 5% of cases. We diagnosed SNCD in a patient affected by sIgMD using the tTG-mRNA assay. One-year GFD induced IgM restoration. This evidence, supporting a link between SNCD and immunoglobulin deficiencies, suggests that we should take a closer look at this association.

Clinical and immunological features of common variable immunodeficiency in China

BACKGROUND

Common variable immunodeficiency (CVID) is one of the most common symptomatic primary immunodeficiency syndromes. The purpose of this article was to broaden our knowledge about CVID for better diagnosis and treatment.

METHODS

Clinical and immunological features of 40 Chinese patients with CVID were analyzed retrospectively.

RESULTS

The median age at onset was 11-year-old (range 4-51 years). The median age at diagnosis was 14.5-year-old (range 5-66 years). The average time of delay in diagnosis was 5.3 years (range 1-41 years). The most common main complaint was fever due to infections (35 cases, 87.5%). Pneumonia (28 cases, 70%) was the most common type of infections. Bronchiectasis was present in 6 patients (15%). Autoimmune disease was detected in 6 cases of CVID, and malignancy in 2 cases. The median total serum levels of IgG, IgA, and IgM at diagnosis were 1.07 g/L, 0.07 g/L, and 0.28 g/L, respectively. The percentages of CD3- /CD19 + B-cells were 1%-3.14%.

CONCLUSIONS

Infection is the most frequent presentation of CVID. Patients with unexplainable infections should receive further examination including serum immunoglobulin (Ig) and lymphocyte subset analysis. Regular and sufficient substitution with Ig is recommended.

Causes of chronic productive cough: An approach to management

A chronic 'productive' or 'wet' cough is a common presenting complaint for patients attending the adult respiratory clinic. Most reviews and guidelines suggest that the causes of a productive cough are the same as those of a non-productive cough and as such the same diagnostic pathway should be followed. We suggest a different diagnostic approach for patients with a productive cough, focussing on the conditions that are the most likely causes of this problem. This review is intended to briefly summarise the epidemiology, clinical features, pathophysiology and treatment of a number of conditions which are often associated with chronic productive cough to aid decision making when encountering a patient with this often distressing symptom. The conditions discussed include bronchiectasis, chronic bronchitis, asthma, eosinophilic bronchitis and immunodeficiency. We also propose an adult version of the paediatric diagnosis of protracted bacterial bronchitis (PBB) in patients with idiopathic chronic productive cough who appear to respond well to low dose macrolide therapy.

Cervical lymph node diseases in children

The lymph nodes are an essential part of the body’s immune system and as such are affected in many infectious, autoimmune, metabolic and malignant diseases. The cervical lymph nodes are particularly important because they are the first drainage stations for key points of contact with the outside world (mouth/throat/nose/eyes/ears/respiratory system) – a critical aspect especially among children – and can represent an early clinical sign in their exposed position on a child’s slim neck.

Involvement of the lymph nodes in multiple conditions is accompanied by a correspondingly large number of available diagnostic procedures. In the interests of time, patient wellbeing and cost, a careful choice of these must be made to permit appropriate treatment. The basis of diagnostic decisions is a detailed anamnesis and clinical examination. Sonography also plays an important role in differential diagnosis of lymph node swelling in children and is useful in answering one of the critical diagnostic questions: is there a suspicion of malignancy? If so, full dissection of the most conspicuous lymph node may be necessary to obtain histological confirmation.

Diagnosis and treatment of childhood cervical lymph node disorders present the attending pediatric and ENT physicians with some particular challenges. The spectrum of differential diagnoses and the varying degrees of clinical relevance – from banal infections to malignant diseases – demand a clear and considered approach to the child’s individual clinical presentation. Such an approach is described in the following paper.