Respiratory disease in common variable immunodeficiency and other primary immunodeficiency disorders

Granulomatous Lymphocyte Interstitial Lung Disease: A Rare Complication of Common Variable Immunodeficiency Managed With Azathioprine and Rituximab

Granulomatous lymphocytic interstitial lung disease (GL-ILD) is a rare, non-infectious pulmonary manifestation of common variable immunodeficiency (CVID). Diagnosing and managing GLILD remains challenging due to its poorly understood pathogenesis and high mortality. We present a complex case of a young female with CVID associated with lung and spinal cord involvement managed with azathioprine and rituximab.

Dysregulated Lymphocyte Antigen Receptor Signaling in Common Variable Immunodeficiency with Granulomatous Lymphocytic Interstitial Lung Disease

PURPOSE

A subset of common variable immunodeficiency (CVID) patients either presents with or develops autoimmune and lymphoproliferative complications, such as granulomatous lymphocytic interstitial lung disease (GLILD), a major cause of morbidity and mortality in CVID. While a myriad of phenotypic lymphocyte derangements has been associated with and described in GLILD, defects in T and B cell antigen receptor (TCR/BCR) signaling in CVID and CVID with GLILD (CVID/GLILD) remain undefined, hindering discovery of biomarkers for disease monitoring, prognostic prediction, and personalized medicine approaches.

METHODS

To identify perturbations of immune cell subsets and TCR/BCR signal transduction, we applied mass cytometry analysis to peripheral blood mononuclear cells (PBMCs) from healthy control participants (HC), CVID, and CVID/GLILD patients.

RESULTS

Patients with CVID, regardless of GLILD status, had increased frequency of HLADR+CD4+ T cells, CD57+CD8+ T cells, and CD21lo B cells when compared to healthy controls. Within these cellular populations in CVID/GLILD patients only, engagement of T or B cell antigen receptors resulted in discordant downstream signaling responses compared to CVID. In CVID/GLILD patients, CD21lo B cells showed perturbed BCR-mediated phospholipase C gamma and extracellular signal-regulated kinase activation, while HLADR+CD4+ T cells and CD57+CD8+ T cells displayed disrupted TCR-mediated activation of kinases most proximal to the receptor.

CONCLUSION

Both CVID and CVID/GLILD patients demonstrate an activated T and B cell phenotype compared to HC. However, only CVID/GLILD patients exhibit altered TCR/BCR signaling in the activated lymphocyte subsets. These findings contribute to our understanding of the mechanisms of immune dysregulation in CVID with GLILD.

Risk Factors of Pneumonia in Primary Antibody Deficiency Patients Receiving Immunoglobulin Therapy: Data from the US Immunodeficiency Network (USIDNET)

BACKGROUND

Despite immunoglobulin replacement (IgRT) therapy, some patients with primary antibody deficiency (PAD) continue to develop respiratory infections. Recurrent and severe respiratory infections, particularly pneumonia, can lead to significant morbidity and mortality. Therefore, we sought to determine the risk factors of developing pneumonia in PAD patients, already receiving IgRT.

METHODS

We evaluated clinical and laboratory features of PAD patients enrolled in the US Immune Deficiency Network (USIDNET) registry by April 2017. Patients were included if they met the following criteria: (1) PAD diagnosis (common variable immunodeficiency (CVID), agammaglobulinemia, hypogammaglobinemia, and specific antibody deficiency (SAD) and (2) available data on infections before and after IgRT. Patients were excluded if they were not receiving IgRT, or if no pre/post infections data were available. Descriptive and multivariable logistic regression analyses were used to identify factors associated with pneumonia post-IgRT.

RESULTS

A total of 1232 patients met the inclusion criteria. Following IgRT, 218 patients (17.7%) were reported to have at least one pneumonia episode. Using multivariate logistic regression analysis, we found a statistically significant increased risk of pneumonia in patients with asthma (OR: 2.55, 95% CI (1.69-3.85), p < 0.001) bronchiectasis (OR: 3.94, 95% CI (2.29-6.80), p < 0.001), interstitial lung disease (ILD) (OR: 3.28, 95%CI (1.43-7.56), p < 0.005), splenomegaly (OR: 2.02, 95%CI (1.08-3.76), p < 0.027), allergies (OR: 2.44, 95% CI [1.44-4.13], p = 0.001), and patients who were not on immunosuppressives (OR: 1.61; 95%CI [1.06-2.46]; p = 0.027). For every 50 unit increase in IgA, the odds of reporting pneumonia post IgRT decreased (OR: 0.86, 95% CI [0.73-1.02], p = 0.062). Infectious organisms were reported in 35 of 218 patients who reported pneumonia after IgRT. Haemophilus influenzae was the most frequently reported (n = 11, 31.43%), followed by Streptococcus pneumoniae (n = 7, 20.00%).

CONCLUSION

Our findings suggest PAD patients with chronic and structural lung disease, splenomegaly, and allergies were associated with persistent pneumonia. However, our study is limited by the cross-sectional nature of the USIDNET database and limited longitudinal data. Further studies are warranted to identify susceptible causes and explore targeted solutions for prevention and associated morbidity and mortality.

CLINICAL IMPLICATIONS

Patients with primary antibody deficiency with structural lung disease, allergies, and splenomegaly are associated with persistent pneumonia post-IgRT.

Granulomatous Lymphocytic Interstitial Lung Disease (GLILD) in Common Variable Immunodeficiency (CVID): A Multicenter Retrospective Study of Patients From Italian PID Referral Centers

Background: Granulomatous and Lymphocytic Interstitial Lung Diseases (GLILD) is a severe non-infectious complication of Common Variable Immunodeficiency (CVID), often associated with extrapulmonary involvement. Due to a poorly understood pathogenesis, GLILD diagnosis and management criteria still lack consensus. Accordingly, it is a relevant cause of long-term loss of respiratory function and is closely associated with a markedly reduced survival. The aim of this study was to describe clinical, immunological, laboratory and functional features of GLILD, whose combination in a predictive model might allow a timely diagnosis. Methods: In a multicenter retrospective cross-sectional study we enrolled 73 CVID patients with radiologic features of interstitial lung disease (ILD) associated to CVID (CVID-ILD) and 125 CVID patients without ILD (controls). Of the 73 CVID-ILD patients, 47 received a definite GLILD diagnosis while 26 received a clinical-radiologic diagnosis of CVID related ILD defined as uILD. Results: In GLILD group we found a higher prevalence of splenomegaly (84.8 vs. 39.2%), autoimmune cytopenia (59.6 vs. 6.4%) and bronchiectasis (72.3 vs. 28%), and lower IgA and IgG serum levels at CVID diagnosis. GLILD patients presented lower percentage of switched-memory B cells and marginal zone B cells, and a marked increase in the percentage of circulating CD21lo B cells (14.2 vs. 2.9%). GLILD patients also showed lower total lung capacity (TLC 87.5 vs. 5.0%) and gas transfer (DLCO 61.5 vs. 5.0%) percent of predicted. By univariate logistic regression analysis, we found IgG and IgA levels at CVID diagnosis, presence of splenomegaly and autoimmune cytopenia, CD21lo B cells percentage, TLC and DCLO percent of predicted to be associated to GLILD. The joint analysis of four variables (CD21lo B cells percentage, autoimmune cytopenia, splenomegaly and DLCO percent of predicted), together in a multiple logistic regression model, yielded an area under the ROC curve (AUC) of 0.98 (95% CI: 0.95-1.0). The AUC was only slightly modified when pooling together GLILD and uILD patients (0.92, 95% CI: 0.87-0.97). Conclusions: we propose the combination of two clinical parameters (splenomegaly and autoimmune cytopenia), one lung function index (DLCO%) and one immunologic variable (CD21lo%) as a promising tool for early identification of CVID patients with interstitial lung disease, limiting the use of aggressive diagnostic procedures.

Granulomatous Lymphocytic Interstitial Lung Disease (GLILD) in Common Variable Immunodeficiency (CVID): A Multicenter Retrospective Study of Patients From Italian PID Referral Centers

Background: Granulomatous and Lymphocytic Interstitial Lung Diseases (GLILD) is a severe non-infectious complication of Common Variable Immunodeficiency (CVID), often associated with extrapulmonary involvement. Due to a poorly understood pathogenesis, GLILD diagnosis and management criteria still lack consensus. Accordingly, it is a relevant cause of long-term loss of respiratory function and is closely associated with a markedly reduced survival. The aim of this study was to describe clinical, immunological, laboratory and functional features of GLILD, whose combination in a predictive model might allow a timely diagnosis. Methods: In a multicenter retrospective cross-sectional study we enrolled 73 CVID patients with radiologic features of interstitial lung disease (ILD) associated to CVID (CVID-ILD) and 125 CVID patients without ILD (controls). Of the 73 CVID-ILD patients, 47 received a definite GLILD diagnosis while 26 received a clinical-radiologic diagnosis of CVID related ILD defined as uILD. Results: In GLILD group we found a higher prevalence of splenomegaly (84.8 vs. 39.2%), autoimmune cytopenia (59.6 vs. 6.4%) and bronchiectasis (72.3 vs. 28%), and lower IgA and IgG serum levels at CVID diagnosis. GLILD patients presented lower percentage of switched-memory B cells and marginal zone B cells, and a marked increase in the percentage of circulating CD21lo B cells (14.2 vs. 2.9%). GLILD patients also showed lower total lung capacity (TLC 87.5 vs. 5.0%) and gas transfer (DLCO 61.5 vs. 5.0%) percent of predicted. By univariate logistic regression analysis, we found IgG and IgA levels at CVID diagnosis, presence of splenomegaly and autoimmune cytopenia, CD21lo B cells percentage, TLC and DCLO percent of predicted to be associated to GLILD. The joint analysis of four variables (CD21lo B cells percentage, autoimmune cytopenia, splenomegaly and DLCO percent of predicted), together in a multiple logistic regression model, yielded an area under the ROC curve (AUC) of 0.98 (95% CI: 0.95-1.0). The AUC was only slightly modified when pooling together GLILD and uILD patients (0.92, 95% CI: 0.87-0.97). Conclusions: we propose the combination of two clinical parameters (splenomegaly and autoimmune cytopenia), one lung function index (DLCO%) and one immunologic variable (CD21lo%) as a promising tool for early identification of CVID patients with interstitial lung disease, limiting the use of aggressive diagnostic procedures.

Consensus of the Italian Primary Immunodeficiency Network on transition management from pediatric to adult care in patients affected with childhood-onset inborn errors of immunity

Medical advances have dramatically improved the long-term prognosis of children and adolescents with inborn errors of immunity (IEIs). Transfer of the medical care of individuals with pediatric IEIs to adult facilities is also a complex task because of the large number of distinct disorders, which requires involvement of patients and both pediatric and adult care providers. To date, there is no consensus on the optimal pathway of the transitional care process and no specific data are available in the literature regarding patients with IEIs. We aimed to develop a consensus statement on the transition process to adult health care services for patients with IEIs. Physicians from major Italian Primary Immunodeficiency Network centers formulated and answered questions after examining the currently published literature on the transition from childhood to adulthood. The authors voted on each recommendation. The most frequent IEIs sharing common main clinical problems requiring full attention during the transitional phase were categorized into different groups of clinically related disorders. For each group of clinically related disorders, physicians from major Italian Primary Immunodeficiency Network institutions focused on selected clinical issues representing the clinical hallmark during early adulthood.

Trained Immunity Based-Vaccines as a Prophylactic Strategy in Common Variable Immunodeficiency. A Proof of Concept Study

Background. A major concern in the care of common variable immunodeficiency (CVID) patients is the persistence of subclinical or recurrent respiratory tract infections (RRTI) despite adequate trough IgG levels, which impacts the quality of life (QoL) and morbidity. Therefore, the development of new approaches to prevent and treat infection, especially RRTI, is necessary. Objectives. We conducted a clinical observational study from May, 2016 to December, 2017 in 20 CVID patients; ten of these patients had a history of RRTI and received the polybacterial preparation MV130, a trained immunity-based vaccine (TIbV) to assess its impact on their QoL and prognosis. Methods. Subjects with RRTI received MV130 for 3 months and were followed up to 12 months after initiation of the treatment. The primary endpoint was a reduction in RRTI at the end of the study. We analyzed the pharmacoeconomic impact on the RRTI group before and after immunotherapy by estimating the direct and indirect costs, and assessed CVID-QoL and cytokine profile. Specific antibody responses to the bacteria contained in MV130 were measured. Results. The RRTI-group treated with TIbV MV130 showed a significant decrease in infection rate (p = 0.006) throughout the 12 months after initiation of the treatment. A decrease in antibiotic use and unscheduled outpatient visits was observed (p = 0.005 and p = 0.002, respectively). Significant increases in anti-pneumococcus and anti-MV130 IgA antibodies (p = 0.039 both) were detected after 12 months of MV130. Regarding the CVID QoL questionnaire, an overall decrease in the score by more than 50% was observed (p < 0.05) which demonstrated that patients experienced an improvement in their QoL. The pharmacoeconomic analysis showed that the real annual direct costs decreased up to 4 times per patient with the prophylactic intervention (p = 0.005). Conclusion. The sublingual administration of the TIbV MV130 significantly reduced the rate of respiratory infections, antibiotic use and unscheduled visits, while increasing specific IgA responses in CVID patients. Additionally, the CVID population felt that their QoL was improved, and a decrease in expenses derived from health care was predicted.

Low IgA Associated With Oropharyngeal Microbiota Changes and Lung Disease in Primary Antibody Deficiency

Common Variable Immunodeficiency (CVID) and X-linked agammaglobulinemia (XLA) are primary antibody deficiencies characterized by hypogammaglobulinemia and recurrent infections, which can lead to structural airway disease (AD) and interstitial lung disease (ILD). We investigated associations between serum IgA, oropharyngeal microbiota composition and severity of lung disease in these patients. In this cross-sectional multicentre study we analyzed oropharyngeal microbiota composition of 86 CVID patients, 12 XLA patients and 49 healthy controls (HC) using next-generation sequencing of the 16S rRNA gene. qPCR was used to estimate bacterial load. IgA was measured in serum. High resolution CT scans were scored for severity of AD and ILD. Oropharyngeal bacterial load was increased in CVID patients with low IgA (p = 0.013) and XLA (p = 0.029) compared to HC. IgA status was associated with distinct beta (between-sample) diversity (p = 0.039), enrichment of (Allo)prevotella, and more severe radiographic lung disease (p = 0.003), independently of recent antibiotic use. AD scores were positively associated with Prevotella, Alloprevotella, and Selenomonas, and ILD scores with Streptococcus and negatively with Rothia. In clinically stable patients with CVID and XLA, radiographic lung disease was associated with IgA deficiency and expansion of distinct oropharyngeal bacterial taxa. Our findings highlight IgA as a potential driver of upper respiratory tract microbiota homeostasis.

Chronic Lung Disease in Primary Antibody Deficiency: Diagnosis and Management

Chronic lung disease is a complication of primary antibody deficiency (PAD) associated with significant morbidity and mortality. Manifestations of lung disease in PAD are numerous. Thoughtful application of diagnostic approaches is imperative to accurately identify the form of disease. Much of the treatment used is adapted from immunocompetent populations. Recent genomic and translational medicine advances have led to specific treatments. As chronic lung disease has continued to affect patients with PAD, we hope that continued advancements in our understanding of pulmonary pathology will ultimately lead to effective methods that alleviate impact on quality of life and survival.

Interstitial Lung Disease in Children With Selected Primary Immunodeficiency Disorders-A Multicenter Observational Study

Primary immunodeficiencies (PIDs) are rare disorders of the immune system encompassing inborn errors of immunity. Primary antibody deficiencies constitute the largest group of PID with common variable immunodeficiency (CVID) being the most common symptomatic form. Combined immunodeficiencies (CID) accompanied by antibody deficiency can mimic CVID and these patients need the verification of the final diagnosis. Respiratory involvement, especially interstitial lung disease (ILD), poses a relevant cause of morbidity and mortality among patients with PID and in some cases is the first manifestation of immunodeficiency. In this study we present a retrospective analysis of a group of children with primary immunodeficiency and ILD - the clinical, radiological, histological characteristics, treatment strategies and outcomes. Eleven children with PID-related ILD were described. The majority of them presented CVID, in three patients CID was recognized. All patients underwent detailed pulmonary diagnostics. In eight of them histological analysis of lung biopsy was performed. We noted that in two out of 11 patients acute onset of ILD with respiratory failure was the first manifestation of the disease and preceded PID diagnosis. The most common histopathological diagnosis was GLILD. Among the analyzed patients three did not require any immunosuppressive therapy. All eight treated children received corticosteroids as initial treatment, but in some of them second-line therapy was introduced. The relevant side effects in some patients were observed. The study demonstrated that the response to corticosteroids is usually prompt. However, the resolution of pulmonary changes may be incomplete and second-line treatment may be necessary.

Appropriate lung management in patients with primary antibody deficiencies

Introduction: Human primary immunodeficiency diseases (PIDs) include a broad spectrum of more than 350 disorders, involving different branches of the immune system and classified as 'rare diseases.' Predominantly antibody deficiencies (PADs) represent more than half of the PIDs diagnosed in Europe and are often diagnosed in the adulthood. Areas covered: Although PAD could first present with autoimmune or neoplastic features, respiratory infections are frequent and respiratory disease represents a relevant cause of morbidity and mortality. Pulmonary complications may be classified as infection-related (acute and chronic), immune-mediated, and neoplastic. Expert opinion: At present, no consensus guidelines are available on how to monitor and manage lung complications in PAD patients. In this review, we will discuss the available diagnostic, prognostic and therapeutic instruments and we will suggest an appropriate and evidence-based approach to lung diseases in primary antibody deficiencies. We will also highlight the possible role of promising new tools and strategies in the management of pulmonary complications. However, future studies are needed to reduce of diagnostic delay of PAD and to better understand lung diseases mechanisms, with the final aim to ameliorate therapeutic options that will have a strong impact on Quality of Life and long-term prognosis of PAD patients.

A 51-Year-Old Man With Unresolved Pulmonary Infiltrates Following Streptococcus pneumoniae Pneumonia

CASE PRESENTATION

A 51-year-old man presented to the clinic 8 weeks after a 6-day hospital admission for severe multilobar pneumonia caused by Streptococcus pneumoniae. His productive cough resolved after antibiotics, but he reported persistent dyspnea. He recounted a lifelong history of recurrent sinusitis but no previous episodes of pneumonia. The patient denied fever, weight loss, or tobacco, alcohol, or drug use. He worked as an upholstery craftsman with no work-related exposures. He had no bird or exotic animal exposures, and no history of travel outside Sacramento, California, where he lived. Aside from the recently completed 2-week course of levofloxacin, he was not taking any medications.

Pulmonary complications of predominantly antibody immunodeficiencies in a tertiary lung center

Background and aims

Respiratory infections are expressed very soon in the life in humoral immunodeficiencies and often lead to chronic irreversible complications such as bronchiectasis and chronic airflow limitation. This study was conducted to evaluate the pulmonary complications of predominantly antibody immunodeficiencies to show the benefits of timely diagnosis and appropriate therapy.

Patients and methods

The information of 48 patients involved with a type of predominantly antibody immunodeficiencies, including sex, type of primary immunodeficiency, age at the onset of symptoms, age at diagnosis, recurrent infections, respiratory symptoms, and pulmonary radiological and functional abnormalities were recorded and analyzed.

Results

In 48 patients evaluated, the mean age at diagnosis was 25.63 years. The mean diagnostic delay was estimated to be 13.62 years. The most recurring clinical manifestations, sinusitis (69.6%), otitis (43.5%), and recurrent pneumonia were the cause of frequent admissions in 68.8% of these patients. Bronchiectasis was frequently found (58.3%) in these patients mostly involving the middle and lower lobes (48.8% and 41.5%, respectively).

Conclusions

Respiratory complications, infectious or non-infectious, determine the prognosis of the disease in patients with predominantly antibody immunodeficiencies. Timely diagnosis and appropriate management may improve life expectancy and the quality of life in these patients.

Imaging of Bronchial Pathology in Antibody Deficiency: Data from the European Chest CT Group

Studies of chest computed tomography (CT) in patients with primary antibody deficiency syndromes (ADS) suggest a broad range of bronchial pathology. However, there are as yet no multicentre studies to assess the variety of bronchial pathology in this patient group. One of the underlying reasons is the lack of a consensus methodology, a prerequisite to jointly document chest CT findings. We aimed to establish an international platform for the evaluation of bronchial pathology as assessed by chest CT and to describe the range of bronchial pathologies in patients with antibody deficiency. Ffteen immunodeficiency centres from 9 countries evaluated chest CT scans of patients with ADS using a predefined list of potential findings including an extent score for bronchiectasis. Data of 282 patients with ADS were collected. Patients with common variable immunodeficiency disorders (CVID) comprised the largest subgroup (232 patients, 82.3%). Eighty percent of CVID patients had radiological evidence of bronchial pathology including bronchiectasis in 61%, bronchial wall thickening in 44% and mucus plugging in 29%. Bronchiectasis was detected in 44% of CVID patients aged less than 20 years. Cough was a better predictor for bronchiectasis than spirometry values. Delay of diagnosis as well as duration of disease correlated positively with presence of bronchiectasis. The use of consensus diagnostic criteria and a pre-defined list of bronchial pathologies allows for comparison of chest CT data in multicentre studies. Our data suggest a high prevalence of bronchial pathology in CVID due to late diagnosis or duration of disease.

High-resolution computed tomography findings in humoral primary immunodeficiencies and correlation with pulmonary function tests

AIM

To compare high-resolution computed tomography (HRCT) findings between humoral primary immunodeficiencies (hPIDs) subtypes; to correlate these findings to pulmonary function tests (PFTs).

METHODS

We retrospectively identified 52 consecutive adult patients with hPIDs who underwent 64-row HRCT and PFTs at the time of diagnosis. On a per-patient basis, an experienced radiologist recorded airway abnormalities (bronchiectasis, airway wall thickening, mucus plugging, tree-in-bud, and air-trapping) and parenchymal-interstitial abnormalities (consolidations, ground-glass opacities, linear and/or irregular opacities, nodules, and bullae/cysts) found on HRCT. The chi-square test was performed to compare the prevalence of each abnormality among patients with different subtypes of hPIDs. Overall logistic regression analysis was performed to assess whether HRCT findings predicted obstructive and/or restrictive PFTs results (absent-to-mild vs moderate-to-severe).

RESULTS

Thirty-eight of the 52 patients with hPIDs showed common variable immunodeficiency disorders (CVID), while the remaining 14 had CVID-like conditions (i.e., 11 had isolated IgG subclass deficiencies and 3 had selective IgA deficiencies). The prevalence of most HRCT abnormalities was not significantly different between CVID and CVID-like patients (P > 0.05), except for linear and/or irregular opacities (prevalence of 31.6% in the CVID group and 0 in the CVID-like group; P = 0.0427). Airway wall thickening was the most frequent HRCT abnormality found in both CVID and CVID-like patients (71% of cases in both groups). The presence of tree-in-bud abnormalities was an independent predictor of moderate-to-severe obstructive defects at PFTs (Odds Ratio, OR, of 18.75, P < 0.05), while the presence of linear and/or irregular opacities was an independent predictor of restrictive defects at PFTs (OR = 13.00; P < 0.05).

CONCLUSION

CVID and CVID-like patients showed similar HRCT findings. Tree-in-bud and linear and/or irregular opacities predicted higher risks of, respectively, obstructive and restrictive defects at PFTs.

Primary immunodeficiency diseases in lung disease: warning signs, diagnosis and management

Background

Pulmonary complications are common in primary immunodeficiency diseases (PID) and contribute to morbidity and mortality in these patients. However, their varied presentation and a general lack of awareness of PID in this setting make early diagnosis and treatment difficult. The aim of this study was to define the warning signs of PID in patients with respiratory manifestations, the necessary diagnostic tests, and the therapeutic management of both children and adults.

Methods

A review of the literature was performed, and 43 PID interdisciplinary specialists were consulted.

Results

This document identifies the pulmonary and extrapulmonary manifestations that should prompt a suspicion of PID, the immunological and respiratory tests that should be included in the diagnostic process according to the level of care, recommendations regarding the use of immunoglobulin replacement therapy according to the specific immunodeficiency, and the minimum recommended immunological and pulmonary monitoring in these patients.

Conclusions

This document is the first to combine scientific evidence with the opinion of a broad panel of experts specializing in the treatment of patients with immunodeficiencies. It aims to provide a useful tool for all practitioners who are regularly involved in the management of these patients.

[Bronchiectasis imaging]

Bronchiectasis are defined as an irreversible focal or diffuse dilatation of the bronchi and can be associated with significant morbidity. The prevalence is currently increasing, probably due to an increased use of thoracic computed tomography (CT). Indeed, the diagnosis relies on imaging and chest CT is the gold standard technique. The main diagnosis criterion is an increased bronchial diameter as compared to that of the companion artery. However, false positives are possible when the artery diameter is decreased, which is called pseudo-bronchiectasis. Other features such as the lack of bronchial tapering, and visibility of bronchi within 1cm of the pleural surface are also diagnostic criteria, and other CT features of bronchial disease are commonly seen. Thoracic imaging also allows severity assessment and long-term monitoring of structural abnormalities. The distribution pattern and the presence of associated findings on chest CT help identifying specific causes of bronchiectasis. Lung MRI and ultra-low dose CT and are promising imaging modalities that may play a role in the future. The objectives of this review are to describe imaging features for the diagnosis and severity assessment of bronchiectasis, to review findings suggesting the cause of bronchiectasis, and to present the new developments in bronchiectasis imaging.

The broad spectrum of lung diseases in primary antibody deficiencies

Human primary immunodeficiency diseases (PIDs) represent a heterogeneous group of more than 350 disorders. They are rare diseases, but their global incidence is more relevant than generally thought. The underlying defect may involve different branches of the innate and/or adaptive immune response. Thus, the clinical picture may range from severe phenotypes characterised by a broad spectrum of infections to milder infectious phenotypes due to more selective (and frequent) immune defects. Moreover, infections may not be the main clinical features in some PIDs that might present with autoimmunity, auto-inflammation and/or cancer. Primary antibody deficiencies (PADs) represent a small percentage of the known PIDs but they are the most frequently diagnosed, particularly in adulthood. Common variable immunodeficiency (CVID) is the most prevalent symptomatic PAD.

PAD patients share a significant susceptibility to respiratory diseases that represent a relevant cause of morbidity and mortality. Pulmonary complications include acute and chronic infection-related diseases, such as pneumonia and bronchiectasis. They also include immune-mediated interstitial lung diseases, such as granulomatous-lymphocytic interstitial lung disease (GLILD) and cancer. Herein we will discuss the main pulmonary manifestations of PADs, the associated functional and imaging findings, and the relevant role of pulmonologists and chest radiologists in diagnosis and surveillance.

The spectrum of lung complications in primary antibody deficiency ranges from asthma or COPD to extremely rare and specific ILDs. Early diagnosis of the underlying immune defect might significantly improve patients' lung disease, QoL and long-term prognosis.http://ow.ly/5cP230kZvOB

Monogenic diseases in respiratory medicine: Clinical perspectives

With the increasing awareness of genetics in respiratory medicine and improvements in molecular diagnostic techniques, many complicated and rare diseases in respiratory medicine can be diagnosed. Most respiratory diseases have no specific phenotype. However, the clinical spectrum of monogenic diseases in respiratory medicine varies, from pulmonary disease to other inherited disorders that involve the lung. The genes that mediate some of these diseases have been identified. Certain monogenic diseases remain poorly characterized clinically. Because of the specificity of the phenotype of respiratory disease, a future challenge will be to correlate the phenotype and genotype and understand its phenotypic variability. With the development of precision medicine, research on monogenic disorders has been intensive and vigorous. In this article, we provide a brief clinical introduction to monogenic diseases in pediatrics.

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.

The Lung in Dysregulated States of Humoral Immunity

In common variable immunodeficiency, lung manifestations are related to different mechanisms: recurrent pneumonias due to encapsulated bacteria responsible for diffuse bronchiectasis, diffuse infiltrative pneumonia with various patterns, and lymphomas, mostly B cell extranodal non-Hodgkin type. The diagnosis relies on significant serum Ig deficiency and the exclusion of any primary or secondary cause. Histopathology may be needed. Immunoglobulin (IgG) replacement is crucial to prevent infections and bronchiectasis. IgG4-related respiratory disease, often associated with extrapulmonary localizations, presents with solitary nodules or masses, diffuse interstitial lung diseases, bronchiolitis, lymphadenopathy, and pleural or pericardial involvement. Diagnosis relies on international criteria including serum IgG4 dosage and significantly increased IgG4/IgG plasma cells ratio in pathologically suggestive biopsy. Respiratory amyloidosis presents with tracheobronchial, nodular, and cystic or diffuse interstitial lung infiltration. Usually of AL (amyloid light chain) subtype, it may be localized or systemic, primary or secondary to a lymphoproliferative process. Very rare other diseases due to nonamyloid IgG deposits are described. Among the various lung manifestations of dysregulated states of humoral immunity, this article covers only those associated with the common variable immunodeficiency, IgG4-related disease, amyloidosis, and pulmonary light-chain deposition disease. Autoimmune connective-vascular tissue diseases or lymphoproliferative disorders are addressed in other chapters of this issue.

Prospective Study of a Cohort of Russian Nijmegen Breakage Syndrome Patients Demonstrating Predictive Value of Low Kappa-Deleting Recombination Excision Circle (KREC) Numbers and Beneficial Effect of Hematopoietic Stem Cell Transplantation (HSCT)

BACKGROUND

Nijmegen breakage syndrome (NBS) is a combined primary immunodeficiency with DNA repair defect, microcephaly, and other phenotypical features. It predominantly occurs in Slavic populations that have a high frequency of carriers with the causative NBN gene c.657_661del5 mutation. Due to the rarity of the disease in the rest of the world, studies of NBS patients are few. Here, we report a prospective study of a cohort of Russian NBS patients.

METHODS

35 Russian NBS patients of ages 1-19 years, referred to our Center between years 2012 and 2016, were prospectively studied.

RESULTS

Despite the fact that in 80% of the patients microcephaly was diagnosed at birth or shortly thereafter, the average delay of NBS diagnosis was 6.5 years. Though 80% of the patients had laboratory signs of immunodeficiency, only 51% of the patients experienced significant infections. Autoimmune complications including interstitial lymphocytic lung disease and skin granulomas were noted in 34%, malignancies-in 57% of the patients. T-cell excision circle (TREC)/kappa-deleting recombination excision circle (KREC) levels were low in the majority of patients studied. Lower KREC levels correlated with autoimmune and oncological complications. Fifteen patients underwent hematopoietic stem cell transplantation (HSCT), 10 of them were alive and well, with good graft function. Three patients in the HSCT group and five non-transplanted patients died; tumor progression being the main cause of death. The probability of the overall survival since NBS diagnosis was 0.76 in the HSCT group and 0.3 in the non-transplanted group.

CONCLUSION

Based on our findings of low TRECs in most NBS patients, independent of their age, TREC detection can be potentially useful for detection of NBS patients during neonatal screening. KREC concentration can be used as a prognostic marker of disease severity. HSCT is a viable treatment option in NBS and should be especially considered in patients with low KREC numbers early on, before development of life-threatening complications.

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.

Pattern recognitions receptors in immunodeficiency disorders

Pattern recognition receptors (PRRs) recognize common microbial or host-derived macromolecules and have important roles in early activation and response of the immune system. Initiation of the innate immune response starts with the recognition of microbial structures called pathogen associated molecular patterns (PAMPs). Recognition of PAMPs is performed by germline-encoded receptors expressed mainly on immune cells termed pattern recognition receptors (PRRs). Several classes of pattern recognition receptors (PRRs) are involved in the pathogenesis of diseases, including Toll-like receptors (TLRs), C-type lectin receptors (CLRs), and Nod-like receptors (NLRs). Patients with primary immune deficiencies (PIDs) affecting TLR signaling can elucidate the importance of these proteins in the human immune system. Defects in interleukin-1 receptor-associated kinase-4 and myeloid differentiation factor 88 (MyD88) lead to susceptibility to infections with bacteria, while mutations in nuclear factor-κB essential modulator (NEMO) and other downstream mediators generally induce broader susceptibility to bacteria, viruses, and fungi. In contrast, TLR3 signaling defects are associated with susceptibility to herpes simplex virus type 1 encephalitis. Other PIDs induce functional alterations of TLR signaling pathways, such as common variable immunodeficiency in which plasmacytoid dendritic cell defects enhance defective responses of B cells to shared TLR agonists. Altered TLR responses to TLR2 and 4 agonists are seen in chronic granulomatous disease (CGD) and X-linked agammaglobulinemia (XLA). Enhanced TLR responses, meanwhile, are seen for TLRs 5 and 9 in CGD, TLRs 4, 7/8, and 9 in XLA, TLRs 2 and 4 in hyper IgE syndrome (HIES), and for most TLRs in adenosine deaminase deficiency. In this review we provide the reader with an update on the role of TLRs and downstream signaling pathways in PID disorders.

Lung Disease in Primary Antibody Deficiencies

Primary antibody deficiencies (PADs) are the most common form of primary immunodeficiency and predispose to severe and recurrent pulmonary infections, which can result in chronic lung disease including bronchiectasis. Chronic lung disease is among the most common complications of PAD and a significant source of morbidity and mortality for these patients. However, the development of lung disease in PAD may not be solely the result of recurrent bacterial infection or a consequence of bronchiectasis. Recent characterization of monogenic immune dysregulation disorders and more extensive study of common variable immunodeficiency have demonstrated that interstitial lung disease (ILD) in PAD can result from generalized immune dysregulation and frequently occurs in the absence of pneumonia history or bronchiectasis. This distinction between bronchiectasis and ILD has important consequences in the evaluation and management of lung disease in PAD. For example, treatment of ILD in PAD typically uses immunomodulatory approaches in addition to immunoglobulin replacement and antibiotic prophylaxis, which are the stalwarts of bronchiectasis management in these patients. Although all antibody-deficient patients are at risk of developing bronchiectasis, ILD occurs in some forms of PAD much more commonly than in others, suggesting that distinct but poorly understood immunological factors underlie the development of this complication. Importantly, ILD can have earlier onset and may worsen survival more than bronchiectasis. Further efforts to understand the pathogenesis of lung disease in PAD will provide vital information for the most effective methods of diagnosis, surveillance, and treatment of these patients.

Magnetic Resonance Imaging May Be a Valuable Radiation-Free Technique for Lung Pathologies in Patients with Primary Immunodeficiency

PURPOSE

In some primary immunodeficiency (PID) patients, especially in the subgroup with common variable immunodeficiency (CVID), radiosensitivity is a concern and avoidance of repeated radiation exposure has been recommended. To investigate the use of lung Magnetic resonance imaging (MRI) instead of Computed Tomography (CT) for the diagnosis and follow-up of various lesions in the lung parenchyma and airways, especially in PID patients in whom x-ray exposure should be limited.

METHODS

The study enrolled 23 patients with PID who underwent thorax CT within the last 3 months and/or who will undergo initial radiological assessment. Lung MRI was performed in all patients to compare the pulmonary findings with CT images.

RESULTS

MRI performance was weaker at detecting bronchiectasis extension, and a low concordance was found between MRI and CT in the assessment of the number of bronchial generations. CT better identified peripheral airway abnormalities, while CT and MRI gave similar results for detecting the presence and extension of consolidation, bullae, mucus plugging, bronchial wall thickening, bronchiectasis severity and nodules.

CONCLUSIONS

Despite the low spatial resolution, higher cost, and low availability, we suggest MRI as a possible radiation-free alternative to CT in selected patients with PID.

Bronchiectasis diagnosed after renal transplantation: a retrospective multicenter study

Background

Bronchiectasis is characterized by abnormal, permanent and irreversible dilatation of the bronchi, usually responsible for daily symptoms and frequent respiratory complications. Many causes have been identified, but only limited data are available concerning the association between bronchiectasis and renal transplantation.

Methods

We conducted a retrospective multicenter study of cases of bronchiectasis diagnosed after renal transplantation in 14 renal transplantation departments (French SPIESSER group). Demographic, clinical, laboratory and CT scan data were collected.

Results

Forty-six patients were included (mean age 58.2 years, 52.2 % men). Autosomal dominant polycystic kidney disease (32.6 %) was the main underlying renal disease. Chronic cough and sputum (50.0 %) were the major symptoms leading to chest CT scan. Mean duration of symptoms before diagnosis was 1.5 years [0–12.1 years]. Microorganisms were identified in 22 patients, predominantly Haemophilus influenzae. Hypogammaglobulinemia was observed in 46.9 % patients. Bronchiectasis was usually extensive (84.8 %). The total bronchiectasis score was 7.4 ± 5.5 with a significant gradient from apex to bases. Many patients remained symptomatic (43.5 %) and/or presented recurrent respiratory tract infections (37.0 %) during follow-up. Six deaths (13 %) occurred during follow-up, but none were attributable to bronchiectasis.

Conclusions

These results highlight that the diagnosis of bronchiectasis should be considered in patients with de novo respiratory symptoms after renal transplantation. Further studies are needed to more clearly understand the mechanisms underlying bronchiectasis in this setting.

Common Variable Immunodeficiency: Diagnosis, Management, and Treatment

Common variable immunodeficiency (CVID) refers to a grouping of antibody deficiencies that lack a more specific genetic or phenotypic classification. It is the immunodeficiency classification with the greatest number of constituents, likely because of the numerous ways in which antibody production can be impaired and the frequency in which antibody production becomes impaired in human beings. CVID comprises a heterogeneous group of rare diseases. Consequently, CVID presents a significant challenge for researchers and clinicians. Despite these difficulties, both our understanding of and ability to manage this grouping of complex immune diseases has advanced significantly over the past 60 years.

Lung disease in primary antibody deficiency

This Review summarises current knowledge on the pulmonary manifestations of primary antibody deficiency (PAD) syndromes in adults. We describe the major PAD syndromes, with a particular focus on common variable immunodeficiency (CVID). Respiratory infection is a common presenting feature of PAD syndromes. Respiratory complications are frequent and responsible for much of the morbidity and mortality associated with these syndromes. Respiratory complications include acute infections, the sequelae of infection (eg, bronchiectasis), non-infectious immune-mediated manifestations (notably the development of granulomatous-lymphocytic interstitial lung disease in CVID), and an increased risk of lymphoma. Although minor abnormalities are detectable in the lungs of most patients with CVID by CT scanning, not all patients develop lung complications. Mechanisms associated with the maintenance of lung health versus lung disease, and the development of bronchiectasis versus immune-mediated complications, are now being dissected. We review the investigation, treatment, and management strategies for PAD syndromes, and include key research questions relating to both infectious and non-infectious complications of PAD in the lung.

CT screening for pulmonary pathology in common variable immunodeficiency disorders and the correlation with clinical and immunological parameters

BACKGROUND

Pulmonary disease is common in patients with common variable immunodeficiency disorders (CVID) and involves infections, chronic airway disease and interstitial lung disease. Chronic pulmonary disease is associated with excess morbidity and early mortality and therefore early detection and monitoring of progression is essential.

METHODS AND PURPOSE

Thin slice CT scan and pulmonary function were used to determine the prevalence and spectrum of chronic (pre-clinical) pulmonary disease in adult CVID patients regardless of symptoms. CT Scans were scored for airway abnormalities (AD) and interstitial lung disease (ILD). Other CVID related complications and B and T lymphocyte subsets were analyzed to identify patients at risk for pulmonary disease.

RESULTS

Significant pulmonary abnormalities were detected in 24 of the 47 patients (51%) consisting of AD in 30% and ILD in 34% of cases. In only 7 (29%) of these 24 patients pulmonary function test proved abnormal. The presence of AD was correlated to (recurrent) lower respiratory tract infections despite IgG therapy. The presence of ILD was correlated to autoimmune disease and a reduction in the numbers of CD4 + T cells, naïve CD4 + T cells, naïve CD8 + T cells and memory B cells and lower IgG through levels over time.

CONCLUSION

Preclinical signs of AD and ILD are common in CVID patients despite Ig therapy and do not correlate to pulmonary function testing. Patients at risk for ILD might be identified by the presence of autoimmunity or a deranged T cell pattern. Larger studies are needed to confirm these findings and to determine thresholds for the T lymphocyte subsets.

Pulmonary radiologic findings in common variable immunodeficiency: clinical and immunological correlations

BACKGROUND

It remains unclear whether interstitial lung disease (ILD) in common variable immunodeficiency (CVID) is a consequence of chronic infection or a manifestation of dysregulated lymphoid proliferation found in those with this condition.

OBJECTIVE

To increase understanding of CVID-associated lung disease by comparing clinical and immunologic associations in those with bronchiectasis, ILD, or no lung disease observed on chest computerized tomography (CT).

METHODS

Retrospective review of electronic medical records of 61 patients with CVID was used to identify clinical and laboratory correlates of bronchiectasis, ground glass opacity, and pulmonary nodules on CT scan.

RESULTS

Significant clinical and immunologic associations were identified for common CT scan findings in CVID. Bronchiectasis was strongly correlated with a CD4+ T-cell count lower than 700 cells/μL and was associated with a history of pneumonia and older age. Pulmonary nodular disease was correlated with increased CD4+:CD8+ T-cell ratios, a history of autoimmune hemolytic anemia or immune thrombocytopenic purpura, elevated IgM, and younger age. Ground glass opacity had similar clinical and laboratory characteristics as those for nodular lung disease but was associated with elevated monocyte counts and the presence of liver disease.

CONCLUSION

CT findings of bronchiectasis or ILD, including ground glass opacity and extensive pulmonary nodules, were correlated with selected clinical and laboratory characteristics. These results suggest divergent processes of CVID lung disease, with bronchiectasis more strongly associated with infection and T-cell lymphopenia and ILD more strongly linked with autoimmunity and lymphoproliferation.

Common variable immunodeficiency-associated granulomatous and interstitial lung disease

PURPOSE OF REVIEW

Common variable immunodeficiency (CVID) is the most common primary immunodeficiency characterized by a deficiency of immunoglobulins. Approximately 30% of the patients develop autoimmune and granulomatous disease. Similar to sarcoidosis, granulomatous disease in CVID can potentially affect all organs, but the lung is the most common. Interstitial lung disease (ILD) manifests in 5-15% of CVID patients, and is present already at the initial diagnosis in the majority of patients. The number of published studies addressing ILD in CVID is limited. However, recently, several studies added substantial knowledge to the field and are discussed within this review in the context of the literature.

RECENT FINDINGS

Histologically, ILD in CVID presents within the known patterns of sarcoid-like granuloma, organizing pneumonia, lymphocytic interstitial pneumonitis and nonspecific interstitial pneumonia. Often, these patterns are concomitantly found in the same patients. Three new articles were published which analyzed high-resolution computed tomography findings and response to treatment.

SUMMARY

In a considerable number of patients, ILD is stable over years and patients may not need any immunosuppressive treatment. Prednisone treatment is often used as the first-line treatment and studies suggest response to treatment in 50-66% of cases. In progressive disease with lung function impairment, combined immunosuppressive treatment is recommended.

Chronic granulomatous disease associated with common variable immunodeficiency - 2 clinical cases

INTRODUCTION

Chronic granulomatous disease associated with common variable immunodeficiency (GD-CVID), although well documented, is rare. Granulomatous lesions can affect several organs and are histologically indistinguishable from sarcoidosis.

CLINICAL CASES

Case 1: A 39-year-old male patient with CVID, asymptomatic although with thrombocytopenia and mediastinal-hilar adenopathies. GD-CVID was diagnosed by bone marrow biopsy. Progressive clinical and radiological improvement was obtained with corticotherapy. Case 2: A 38-year-old male patient with CVID, suffered from asthenia, anorexia, myalgia, lower limbs edemas, and dry cough. He had mediastinal and bilateral hilar adenopathies within which biopsy revealed non-necrotizing granulomatous infiltrate. A spontaneous resolution was detected after 9 months of evolution.

CONCLUSION

GD-CVID is rare and can mimetize other pathologies, namely, sarcoidosis; it should therefore be publicized and discussed so that it becomes a general clinical knowledge.

Diffuse panbronchiolitis in a patient with common variable immunodeficiency: a casual association or a pathogenetic correlation?

Diffuse panbronchiolitis (DPB) is an idiopathic inflammatory disease that seems to have an immunological pathogenesis and that causes a severe progressive suppurative and obstructive respiratory disorder. Common variable immunodeficiency (CVID) is the most common serious primary immunodeficiency and it is often associated with respiratory diseases. Herein, we describe a case of DPB in a 41-year-old man affected by CVID. We examined the patient's lungs, focusing on the characteristics of the inflammatory cells and of the foamy macrophagic nodules typical of DPB. Immunohistochemical typing of the lymphocytic infiltrate showed that B-cells were almost absent, matching the immunological profile of CVID. The case described is the first case reported in the literature of DPB in a patient affected by CVID. Moreover it seems to confirm the correlation between an immunodeficiency status and the development of DPB and provides more information on the accumulation of nodules of foamy macrophages in DPB.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5310709471138338.

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.

Pulmonary manifestations of primary immunodeficiency disorders in children

Primary immunodeficiencies (PIDs) are inherited disorders in which one or several components of immune system are decreased, missing, or of non-appropriate function. These diseases affect the development, function, or morphology of the immune system. The group of PID comprises more than 200 different disorders and syndromes and the number of newly recognized and revealed deficiencies is still increasing. Their clinical presentation and complications depend on the type of defects and there is a great variability in the relationship between genotypes and phenotypes. A variation of clinical presentation across various age categories is also presented and children could widely differ from adult patients with PID. Respiratory symptoms and complications present a significant cause of morbidity and also mortality among patients suffering from different forms of PIDs and they are observed both in children and adults. They can affect primarily either upper airways (e.g., sinusitis and otitis media) or lower respiratory tract [e.g., pneumonia, bronchitis, bronchiectasis, and interstitial lung diseases (ILDs)]. The complications from lower respiratory tract are usually considered to be more important and also more specific for PIDs and they determinate patients' prognosis. The spectrum of the causal pathogens usually demonstrates typical pattern characteristic for each PID category. The respiratory signs of PIDs can be divided into infectious (upper and lower respiratory tract infections and complications) and non-infectious (ILDs, bronchial abnormalities - especially bronchiectasis, malignancies, and benign lymphoproliferation). Early diagnosis and appropriate therapy can prevent or at least slow down the development and course of respiratory complications of PIDs.

The variable in common variable immunodeficiency: a disease of complex phenotypes

Common variable immunodeficiency (CVID) is the most common and clinically most important severe primary antibody deficiency and is characterized by low levels of IgG, IgA, and/or IgM, with a failure to produce specific antibodies. This diagnostic category represents a heterogeneous group of disorders, which present not only with acute and chronic infections but also with a range of inflammatory and autoimmune disorders as well as an increased incidence of lymphoma and other malignancies. Patients can now be categorized into distinct clinical phenotypes based on analysis of large cohort studies and be further stratified by immunologic laboratory testing. The biologic importance of this categorization is made clear by the 11-fold increase in mortality if even one of these phenotypes (cytopenias, lymphoproliferation, or enteropathy) is present. Limited progress in defining the underlying molecular causes has been made with known causative single gene defects accounting for only 3% of cases, and, for this and the reasons mentioned above, CVID remains resolute in its variability. This review provides a practical approach to risk stratification of these complex phenotypes by using current clinical categories and laboratory biomarkers. The effects of infection as well as inflammatory and autoimmune complications on different organ systems are discussed alongside strategies to reduce diagnostic delay. Recent developments in diagnostics and therapy are also explored.

Tertiary lymphoid neogenesis is a component of pulmonary lymphoid hyperplasia in patients with common variable immunodeficiency

BACKGROUND

Despite reducing pneumonia and other infections, antibody replacement does not appear to treat pulmonary lymphoid hyperplasia (PLH) in patients with common variable immunodeficiency (CVID). The pathogenesis and optimal treatments remain to be clarified.

OBJECTIVE

We aimed to better understand the pathology of CVID-associated lung disease. Tertiary lymphoneogenesis, although a component of interstitial lung disease associated with autoimmune diseases, has not previously been explored in patients with CVID.

METHODS

We examined the clinical characteristics and pathologic findings of 6 patients with CVID with nodular/infiltrative lung disease who had biopsy specimens demonstrating PLH.

RESULTS

In these subjects regions of PLH contained distinct B- and T-cell zones, with B-cell predominance in 1 patient and T-cell predominance in the others. Colocalization of Ki67, Bcl6, and CD23 within this ectopic lymphoid architecture demonstrated tertiary lymphoneogenesis with active centers of cellular proliferation. One patient received rituximab with improved pulmonary radiologic findings.

CONCLUSION

Ectopic lymphoid tissue forming germinal centers suggest tertiary lymphoneogenesis in CVID-associated lung disease. B cell-targeted therapy might disrupt CVID-associated lymphoid hyperplasia.

Follicular bronchiolitis associated with common variable immunodeficiency

Common variable immunodeficiency is one of the most frequent immunity alterations. The most common clinical presentation occurs with recurrent respiratory infections, from pneumonia to otitis, and may be associated with other diseases such as bronchiectasis or interstitial lung diseases. We report the case of a 28-year-old patient with frequent respiratory infections and nodular pulmonary infiltrates, who was diagnosed with common variable immunodeficiency and follicular bronchiolitis. In some cases, follicular bronchiolitis is associated with immunodeficiencies and should be included in a differential diagnosis with lymphoid nodular hyperplasia, lymphocytic interstitial pneumonia and low-grade BALT lymphoma.