Follicular Bronchiolitis: A Literature Review

Review of pulmonary manifestations of rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoinflammatory disorder that primarily affects joints. However, RA can involve extra-articular structures as well, including the lungs, affecting significant morbidity and mortality, though the precise mechanisms of extra-articular RA are still under investigation. Accurate diagnosis of these conditions can be challenging and requires a multidisciplinary approach. This review aims to describe proposed mechanisms of pulmonary RA and characterize common, clinically relevant pulmonary manifestations of RA, including parenchymal disease (interstitial lung disease and multiple pulmonary nodules), small and large airway involvement, and pleural effusions. In particular, CT imaging may reveal developing pulmonary disease before clinical symptoms present, revealing the importance of maintaining a high degree of suspicion for RA-related pulmonary disease.

Rare interstitial lung diseases: a narrative review

Background and Objective

Interstitial lung diseases (ILDs) encompass over 200 entities. Among them, fibrosing lung diseases, have recently generated special interest due to the emerging therapies for their management. However, it is important to deepen our knowledge of other less prevalent ILD, since many of them are associated with a poor prognosis. This narrative review aims to provide a practical and up-to-date description of some poorly recognized ILD. It covers rare idiopathic interstitial pneumonias and their histologic patterns, genetic disorders with interstitial lung involvement (Hermansky-Pudlak syndrome), and ILD associated with benign proliferation of pulmonary lymphoid tissue, namely follicular bronchiolitis and granulomatous-lymphocytic interstitial lung disease.

Methods

Electronic searches of PubMed and Google Scholar using specific keywords were conducted. Articles underwent screening for relevance, covering review articles, meta-analyses, systematic reviews, case series, prospective studies, society guidelines, editorials in peer-reviewed journals; scientific books on the subject. The data included was limited to English and Spanish publications.

Key Content and Findings

Despite the low prevalence of these diseases, the increased recognition of radiological patterns, pathological features, and diagnostic procedures, have permitted their better characterization. This review highlights epidemiology, clinical presentation, diagnosis, natural history, and treatment.

Conclusions

Lesser-studied ILD represent a diagnostic and therapeutic challenge and can be frequently misdiagnosed. Also, due to the lack of randomized controlled trials, there are no well-established therapeutic options. Further studies or registries are needed to improve accurate diagnosis and management.

CD4+ T-cell-dependent differentiation of CD23+ follicular B cells contributes to the pulmonary pathology in a primary Sjögren's syndrome mouse model

Introduction

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease that affects the function of exocrine glands, such as the lacrimal and the salivary glands. Extraglandular lesions and malignant lymphoma also occur during the progressive stage of pSS. We have, herein, focused on the pulmonary lesions of pSS and have aimed clarifying their pathophysiological mechanism by comparing the glandular with the extraglandular lesions observed in a mouse model of pSS.

Results

The histopathological analysis of lung tissues obtained from NFS/sld mice that have undergone neonatal thymectomy was performed. Moreover, in vivo and in vitro experiments were conducted along with immunological analyses in order to characterize the unique phenotypes of the pulmonary lesions identified in these pSS model mice. Inflammatory lesions with a bronchus-associated lymphoid tissue-like structure were identified in the lungs of pSS model mice. In addition, relative to salivary gland lesions, pulmonary lesions showed increased CD23⁺ follicular B (FB) cells. In vitro and pulmonary B cells were more readily driven to CD23⁺ FB cell phenotype than salivary gland B cells in pSS model mice. Furthermore, the CD23⁺ FB cell differentiation was found to be enhanced in a CD4⁺ T-cell-dependent manner under a Th2-type condition in the lungs of herein examined pSS model mice.

Discussion

A Th2-type response in the pSS lung may promote the progression of autoimmune lesions through an enhanced abnormal differentiation of B cells.

Thoracic Involvement in Systemic Autoimmune Rheumatic Diseases: Pathogenesis and Management

Thoracic involvement is one of the main determinants of morbidity and mortality in patients with autoimmune rheumatic diseases (ARDs), with different prevalence and manifestations according to the underlying disease. Interstitial lung disease (ILD) is the most common pulmonary complication, particularly in patients with systemic sclerosis (SSc), idiopathic inflammatory myopathies (IIMs) and rheumatoid arthritis (RA). Other thoracic manifestations include pulmonary arterial hypertension (PAH), mostly in patients with SSc, airway disease, mainly in RA, and pleural involvement, which is common in systemic lupus erythematosus and RA, but rare in other ARDs.In this review, we summarize and critically discuss the current knowledge on thoracic involvement in ARDs, with emphasis on disease pathogenesis and management. Immunosuppression is the mainstay of therapy, particularly for ARDs-ILD, but it should be reserved to patients with clinically significant disease or at risk of progressive disease. Therefore, a thorough, multidisciplinary assessment to determine disease activity and degree of impairment is required to optimize patient management. Nevertheless, the management of thoracic involvement-particularly ILD-is challenging due to the heterogeneity of disease pathogenesis, the variety of patterns of interstitial pneumonia and the paucity of randomized controlled clinical trials of pharmacological intervention. Further studies are needed to better understand the pathogenesis of these conditions, which in turn is instrumental to the development of more efficacious therapies.

The immune system as a driver of mitochondrial disease pathogenesis: a review of evidence

BACKGROUND

Genetic mitochondrial diseases represent a significant challenge to human health. These diseases are extraordinarily heterogeneous in clinical presentation and genetic origin, and often involve multi-system disease with severe progressive symptoms. Mitochondrial diseases represent the most common cause of inherited metabolic disorders and one of the most common causes of inherited neurologic diseases, yet no proven therapeutic strategies yet exist. The basic cell and molecular mechanisms underlying the pathogenesis of mitochondrial diseases have not been resolved, hampering efforts to develop therapeutic agents.

MAIN BODY

In recent pre-clinical work, we have shown that pharmacologic agents targeting the immune system can prevent disease in the Ndufs4(KO) model of Leigh syndrome, indicating that the immune system plays a causal role in the pathogenesis of at least this form of mitochondrial disease. Intriguingly, a number of case reports have indicated that immune-targeting therapeutics may be beneficial in the setting of genetic mitochondrial disease. Here, we summarize clinical and pre-clinical evidence suggesting a key role for the immune system in mediating the pathogenesis of at least some forms of genetic mitochondrial disease.

CONCLUSIONS

Significant clinical and pre-clinical evidence indicates a key role for the immune system as a significant in the pathogenesis of at least some forms of genetic mitochondrial disease.

Follicular Bronchiolitis Associated With Primary IgG2/IgG4 Deficiency in a Previously Healthy 40-Year-Old Woman

Follicular bronchiolitis (FB) associated with immunodeficiency is not commonly reported in peer-reviewed literature. Herein, we present a case of FB associated with IgG2/IgG4 deficiency. The presence of non-specific respiratory symptoms, including cough and dyspnea with exertion, led to a CT scan of the chest, which showed diffuse, peripheral, micronodular tree-in-bud opacities and an isolated area of bronchiectasis. Despite an extensive workup, including a non-diagnostic transbronchial biopsy, no obvious etiology for the patient’s clinical presentation was established, and a surgical lung biopsy was needed to confirm the diagnosis of FB. Further lab testing to evaluate for immunodeficiency confirmed an isolated deficiency in both IgG2 and IgG4. Although treating the underlying cause of FB is the standard of care, there are no established guidelines regarding standard management of FB associated with immunodeficiency, specifically IgG2/IgG4 deficiency. Therefore, a careful evaluation for immunodeficiency should be considered when evaluating for the underlying etiology of FB, as management options differ depending on the underlying diagnosis.

[Spontaneous remission of follicular bronchiolitis with nonspecific interstitial pneumonia: A case report and literature review]

A 41-year-old female patient was admitted in Department of Respiratory and Critical Care Medicine, Peking University Third Hospital because of having cough for a year. Multiple subpleural ground grass and solid nodules could be seen on her CT scan. Four months before admission, she began to experience dry mouth and eyes, blurred vision, finger joints pain, muscle pain and weakness in both lower limbs and weight loss. At the time of admission, the patient's vital signs were normal, no skin rash was seen, breath sounds in both lungs were clear, no rales or wheeze, no deformities in her hands, no redness, swelling, or tenderness in the joints. There was no edema in both lower limbs. Some lab examinations were performed. Tumor markers including squamous cell carcinoma (SCC) antigen, neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), Cyfra21-1, pro-gastrin-releasing peptide (proGRP), carbohydrate antigen 125 (CA125) and carbohydrate antigen 199 (CA199) were all normal. The antinuclear antibody, rheumatoid factor, antineutrophil cytoplasmic antibody, anti-dsDNA antibody, anti-Sm antibody, anti-SSA/SSB antibody, anti-ribonucleoprotein (RNP) antibody, anti-Jo-1 antibody, anti-SCL-70 antibody and anti-ribosomal antibody were all negative. The blood IgG level was normal. The blood fungal β-1.3-D glucose, aspergillus galactomannan antigen, sputum bacterial and fungal culture, and sputum smear test for acid-fast staining were all negative. Lung function was normal. Bronchoscopy showed the airways and mucosa were normal. To clarify the diagnosis, she underwent thoracoscopic lung biopsy, the histopathology revealed follicular bronchiolitis (FB) with nonspecific interstitial pneumonia (NSIP). She did not receive any treatment and after 7 months, the lung opacities were spontaneously resolved. After 7 years of follow-up, the opacities in her lung did not relapse. To improve the understanding of FB, a literature research was performed with "follicular bronchiolitis" as the key word in Wanfang, PubMed and Ovid Database. The time interval was from January 2000 to December 2018. Relative articles were retrieved and clinical treatments and prognosis of FB were analyzed. Eighteen articles concerning FB with complete records were included in the literature review. A total of 51 adult patients with FB were reported, including 18 primary FB and 33 secondary FB, and autoimmune disease was the most common underlying cause. Forty-one (80.4%) patients were prescribed with corticosteroids and/or immunosuppressive agents, 6 (11.8%) patients were treated with anti-infective, 5 (9.8%) patients did not receive any treatment. The longest follow-up period was 107 months. Among the 5 patients without any treatment, 1 patients died of metastatic melanoma, the lung opacities were unchanged in 1 patient and getting severe in 3 patients. In conclusion, FB is a rare disease, the treatment and prognosis are controversial. Corticosteroid and immunosuppressive agents could be effective. This case report suggests the possibility of spontaneous remission of FB.

[Spontaneous remission of follicular bronchiolitis with nonspecific interstitial pneumonia: A case report and literature review]

A 41-year-old female patient was admitted in Department of Respiratory and Critical Care Medicine, Peking University Third Hospital because of having cough for a year. Multiple subpleural ground grass and solid nodules could be seen on her CT scan. Four months before admission, she began to experience dry mouth and eyes, blurred vision, finger joints pain, muscle pain and weakness in both lower limbs and weight loss. At the time of admission, the patient's vital signs were normal, no skin rash was seen, breath sounds in both lungs were clear, no rales or wheeze, no deformities in her hands, no redness, swelling, or tenderness in the joints. There was no edema in both lower limbs. Some lab examinations were performed. Tumor markers including squamous cell carcinoma (SCC) antigen, neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), Cyfra21-1, pro-gastrin-releasing peptide (proGRP), carbohydrate antigen 125 (CA125) and carbohydrate antigen 199 (CA199) were all normal. The antinuclear antibody, rheumatoid factor, antineutrophil cytoplasmic antibody, anti-dsDNA antibody, anti-Sm antibody, anti-SSA/SSB antibody, anti-ribonucleoprotein (RNP) antibody, anti-Jo-1 antibody, anti-SCL-70 antibody and anti-ribosomal antibody were all negative. The blood IgG level was normal. The blood fungal β-1.3-D glucose, aspergillus galactomannan antigen, sputum bacterial and fungal culture, and sputum smear test for acid-fast staining were all negative. Lung function was normal. Bronchoscopy showed the airways and mucosa were normal. To clarify the diagnosis, she underwent thoracoscopic lung biopsy, the histopathology revealed follicular bronchiolitis (FB) with nonspecific interstitial pneumonia (NSIP). She did not receive any treatment and after 7 months, the lung opacities were spontaneously resolved. After 7 years of follow-up, the opacities in her lung did not relapse. To improve the understanding of FB, a literature research was performed with "follicular bronchiolitis" as the key word in Wanfang, PubMed and Ovid Database. The time interval was from January 2000 to December 2018. Relative articles were retrieved and clinical treatments and prognosis of FB were analyzed. Eighteen articles concerning FB with complete records were included in the literature review. A total of 51 adult patients with FB were reported, including 18 primary FB and 33 secondary FB, and autoimmune disease was the most common underlying cause. Forty-one (80.4%) patients were prescribed with corticosteroids and/or immunosuppressive agents, 6 (11.8%) patients were treated with anti-infective, 5 (9.8%) patients did not receive any treatment. The longest follow-up period was 107 months. Among the 5 patients without any treatment, 1 patients died of metastatic melanoma, the lung opacities were unchanged in 1 patient and getting severe in 3 patients. In conclusion, FB is a rare disease, the treatment and prognosis are controversial. Corticosteroid and immunosuppressive agents could be effective. This case report suggests the possibility of spontaneous remission of FB.

Rheumatoid Arthritis Accompanying Diffuse Panbronchiolitis

A 58-year-old woman with rheumatoid arthritis (RA) visited our hospital complaining of a persistent cough and sputum for the past year. She had a high cold hemagglutinin titer and chronic sinusitis. Chest computed tomography revealed bilateral diffuse centrilobular nodules, bronchiectasis, and bronchial wall thickening. A surgical lung biopsy was performed that confirmed diffuse panbronchiolitis (DPB) because of the lymphocytic and plasmacytic infiltrates in the respiratory bronchioles. Her condition improved after the administration of clarithromycin. Several cases of RA complicating DPB have previously been reported, but only in Japan. We need to consider DPB as a bronchiolitis types accompanying RA among Japanese patients.

Is the combination of bilateral pulmonary nodules and mosaic attenuation on chest CT specific for DIPNECH?

Background

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is characterized by multifocal proliferation of pulmonary neuroendocrine cells. On chest CT, DIPNECH exhibits bilateral pulmonary nodules and mosaic attenuation in most patients. We sought to: (1) assess the specificity of this pattern (i.e., bilateral pulmonary nodules together with mosaic attenuation) for DIPNECH; (2) describe its differential diagnosis; and (3) identify the clinico-radiologic features that may help prioritize DIPNECH over other diagnostic considerations.

Methods

We searched the Mayo Clinic records from 2015 to 2019 for patients with bilateral pulmonary nodules and mosaic attenuation on CT who had a diagnostic lung biopsy. A thoracic radiologist reviewed all CT scans. Chi-square test was used for categorical variables, and odds ratios were utilized to measure the association between certain variables and DIPNECH.

Results

Fifty-one patients met our inclusion criteria; 40 (78%) were females and 34 (67%) were never-smokers. Median age was 65 (interquartile range 55–73) years. Lung biopsy was surgical in 21 patients (41%), transbronchial in 17 (33%), and transthoracic in 12 (24%); explanted lungs were examined in 1 (2%). Metastatic/multifocal cancer was the most common diagnosis, and was found in 17 (33%) cases. Bronchiolitis was diagnosed in 12 patients (24%), interstitial lung disease in 10 (20%), and DIPNECH in 5 (10%). Previous diagnosis of an obstructive lung disease (odds ratio 15.8; P = 0.002), and peribronchial nodular distribution on CT (odds ratio 14.4; P = 0.006) were significantly correlated with DIPNECH. Although statistical significance was not reached, DIPNECH nodules were more likely to display solid attenuations (80% vs. 67%, P = 0.45), and were more numerous; > 10 nodules were seen in 80% of DIPNECH cases vs. 52% in others (P = 0.23). Because DIPNECH primarily affects women, we analyzed the women-only cohort and found similar results.

Conclusions

Various disorders can manifest the CT pattern of bilateral pulmonary nodules together with mosaic attenuation, and this combination is nonspecific for DIPNECH, which was found in only 10% of our cohort. Previous diagnosis of an obstructive lung disease, and peribronchial distribution of the nodules on CT increased the likelihood of DIPNECH vs. other diagnoses.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-02103-w.

A functionally improved case of obstructive impairment caused by systemic lupus erythematosus

A 67-year-old Asian woman presented with dyspnoea on exertion and wheezing. She had been diagnosed with systemic lupus erythematosus (SLE) and bronchial asthma at the ages of 42 and 50 years, respectively. Her SLE was stable with the use of 1 mg of daily prednisolone for more than 5 years. To control her bronchial asthma a combination of a low-dose inhaled corticosteroid (ICS) and long-acting β₂-agonist (LABA) (125/5 µg of fluticasone/formoterol), 10 mg of montelukast and 400 mg of theophylline were prescribed. She had a smoking history of 28 pack-years and quit smoking at the age of 45 years.

Pulmonary lymphoproliferative diseases are often associated with collagen diseases. In addition to treatment of the primary disease, additional treatments may be considered depending on the pathology presented in the case.https://bit.ly/3vKqsls

Immune Dysregulation, Polyendocrinopathy, Enteropathy, X-Linked Syndrome Manifesting as Lymphocytic Interstitial Pneumonia and Treatment-Resistant Bullous Pemphigoid

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a rare immune deficiency with a broad clinical presentation. IPEX syndrome causes dysfunctional regulatory T cells, increasing the risk of autoimmune diseases. In this case report, we describe a 7-year-old boy with lymphocytic interstitial pneumonia and bullous pemphigoid who was recently diagnosed with IPEX syndrome.

Pediatric follicular bronchiolitis with severe atelectasis: a case report

Follicular bronchiolitis is a rare pulmonary disorder characterized by the presence of multiple hyperplastic lymphoid follicles with a peribronchiolar distribution. An 11-year-old girl with total atelectasis of the right middle lobe (RML) and diffuse multiple small nodules at both lung bases presented to our hospital with frequent upper respiratory infections and pneumonia. The disease progressed during a 3-month period of macrolide therapy, and thoracoscopic biopsy with lobectomy of the atelectatic RML was performed. The histopathologic diagnosis was follicular bronchiolitis. The patient's pulmonary function improved dramatically after oral steroid treatment. It can be difficult to diagnose follicular bronchiolitis based solely on clinical, laboratory, and radiologic findings; the disorder must be confirmed histopathologically. A patient with longstanding irreversible atelectasis and resulting recurrent respiratory infection may require lobectomy for the diagnosis and treatment of follicular bronchiolitis.

Primary Pulmonary B-Cell Lymphoma: A Review and Update

Simple Summary

The group of B-cell lymphomas primarily involving the lung encompasses different histological entities with distinct biological aspects, while sharing some clinical and radiological features related to their common anatomic site of occurrence. Recent molecular advances in the molecular genetics of these lesions have substantially improved of our understanding of the mechanisms of lymphomagenesis, adding novel information to histology in order to better characterize and manage these diseases. This review summarizes the available clinical, radiological, pathological, and molecular data on primary pulmonary B-cell lymphomas, discusses the mechanisms of lymphomagenesis, and highlights the role of a multi-disciplinary management in overcoming the diagnostic and therapeutic challenges in this setting.

Abstract

Primary pulmonary B-cell lymphomas (PP-BCLs) comprise a group of extranodal non-Hodgkin lymphomas of B-cell origin, which primarily affect the lung without evidence of extrapulmonary disease at the time of diagnosis and up to 3 months afterwards. Primary lymphoid proliferations of the lung are most often of B-cell lineage, and include three major entities with different clinical, morphological, and molecular features: primary pulmonary marginal zone lymphoma of mucosa-associated lymphoid tissue (PP-MZL, or MALT lymphoma), primary pulmonary diffuse large B cell lymphoma (PP-DLBCL), and lymphomatoid granulomatosis (LYG). Less common entities include primary effusion B-cell lymphoma (PEL) and intravascular large B cell lymphoma (IVLBCL). A proper workup requires a multidisciplinary approach, including radiologists, pneumologists, thoracic surgeons, pathologists, hemato-oncologists, and radiation oncologists, in order to achieve a correct diagnosis and risk assessment. Aim of this review is to analyze and outline the clinical and pathological features of the most frequent PP-BCLs, and to critically analyze the major issues in their diagnosis and management.

Recent advances in the understanding of bronchiolitis in adults

Bronchiolitis is injury to the bronchioles (small airways with a diameter of 2 mm or less) resulting in inflammation and/or fibrosis. Bronchioles can be involved in pathologic processes that involve predominantly the lung parenchyma or large airways, but, in some diseases, bronchioles are the main site of injury ("primary bronchiolitis"). Acute bronchiolitis caused by viruses is responsible for most cases of bronchiolitis in infants and children. In adults, however, there is a wide spectrum of bronchiolar disorders and most are chronic. Many forms of bronchiolitis have been described in the literature, and the terminology in this regard remains confusing. In clinical practice, a classification scheme based on the underlying histopathologic pattern (correlates with presenting radiologic abnormalities) facilitates the recognition of bronchiolitis and the search for the inciting cause of the lung injury. Respiratory bronchiolitis is the most common form of bronchiolitis in adults and is usually related to cigarette smoking. Currently, the diagnosis of respiratory bronchiolitis is generally achieved based on the clinical context (smoking history) and chest CT findings. Constrictive (obliterative) bronchiolitis is associated with airflow obstruction and is seen in various clinical contexts including environmental/occupational inhalation exposures, transplant recipients (bronchiolitis obliterans syndrome), and many others. Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is increasingly recognized and can be associated with progressive airflow obstruction related to constrictive bronchiolitis ("DIPNECH syndrome"). Diffuse aspiration bronchiolitis is a form of aspiration-related lung disease that is often unsuspected and confused for interstitial lung disease. Novel forms of bronchiolitis have been described, including lymphocytic bronchiolitis and alveolar ductitis with emphysema recently described in employees at a manufacturing facility for industrial machines. Bronchiolitis is also a component of vaping-related lung injury encountered in the recent outbreak.

Follicular Bronchiolitis: Two Cases with Varying Clinical and Radiological Presentation

Follicular bronchiolitis (FB) is a rare bronchiolar disorder associated with hyperplasia of the bronchial-associated lymphoid tissue (BALT). It is characterized by the development of lymphoid follicles with germinal centers in the walls of small airways. It falls under the category of lymphoproliferative pulmonary diseases (LPDs) and commonly occurs in relation to connective tissue disease, immunodeficiency, infections, interstitial lung disease (ILD), and inflammatory airway diseases. Computerized tomography (CT) findings include centrilobular nodules with patchy ground glass infiltrate, tree-in-bud findings, and air trapping. It can very rarely present as diffuse cystic lung disease. We present two cases of FB. The first case is associated with Human Immunodeficiency Virus (HIV) infection and asthma with diffuse cystic changes on the CT. The second case is associated with reactive airway disease and gastroesophageal reflux disease (GERD) with the classic centrilobular nodules and ground glass opacities on the CT.

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.

Thoracic Manifestations of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is commonly associated with pulmonary disease that can affect any anatomic compartment of the thorax. The most common intrathoracic manifestations of RA include interstitial lung disease, airway disease, pleural disease, rheumatoid nodules, and drug-induced toxicity. Patients with RA with thoracic involvement often present with nonspecific respiratory symptoms, although many are asymptomatic. Therefore, clinicians should routinely consider pulmonary disease when evaluating any patient with RA, particularly one with known risk factors. The optimal screening, diagnostic, and treatment strategies for RA-associated pulmonary disease remain uncertain and are the focus of ongoing investigation.

Perplexing case of lung mass perfectly mimicking a malignancy

A 35-year-old man, a known asthmatic and with a history of smoking presented with a history of recurrent episodes of mild haemoptysis. On examination, there was decreased intensity of breath sounds on the right infraclavicular area. The chest X-ray and CT chest showed a mass in right upper lobe with nodules in the other lobe. The VAT showed large heavily vascularised mass with surface laden with multiple nodules. The wedge resection of the mass was taken and sent for histopathology examination. The biopsy result showed picture suggestive of connective tissue disease associated follicular bronchiolitis. The patient did not have any signs or symptoms of connective tissue disease. However he was positive for Rheumatoid factor, ANA, anti-RO, anti-CCP antibodies. He was started on steroids and azathioprine. After 6 months of treatment, the size of the mass and nodules reduced by 50% and ESR was reduced to 5 from 75.

Factors Beyond Lack of Antibody Govern Pulmonary Complications in Primary Antibody Deficiency

PURPOSE

Pulmonary complications occur frequently in primary antibody deficiency (PAD). While the impact of antibody deficiency may appear implicit for certain respiratory infections, immunoglobulin replacement therapy does not completely ameliorate pulmonary complications in PAD. Thus, there may be antibody-independent factors influencing susceptibility to respiratory disease in PAD, but these remain incompletely defined.

METHODS

We harnessed the multicenter US Immunodeficiency Network primary immunodeficiency registry to compare prevalence of asthma, bronchiectasis, interstitial lung disease (ILD), and respiratory infections between two forms of PAD: common variable immunodeficiency (CVID) and x-linked agammaglobulinemia (XLA). We also defined the clinical and immunological characteristics associated with ILD and asthma in CVID.

RESULTS

Asthma, bronchiectasis, ILD, pneumonia, and upper respiratory infections were more prevalent in CVID than XLA. ILD was associated with autoimmunity, bronchiectasis, and pneumonia as well as fewer B and T cells in CVID. Asthma was the most common chronic pulmonary complication and associated with lower IgA and IgM in CVID. Age of symptom onset or CVID diagnosis was unrelated with ILD or asthma.

CONCLUSION

Despite having less severe immunoglobulin deficiency than XLA, respiratory infections, ILD, and asthma were more common in CVID. Among CVID patients, ILD was associated with autoimmunity and reduced lymphocytes and asthma with lower immunoglobulins. Though our results are tempered by registry limitations, they provide evidence that factors beyond lack of antibody promote pulmonary complications in PAD. Efforts to understand how genetic etiology, nature of concurrent T cell deficiency, and propensity for autoimmunity shape pulmonary disease may improve treatment of PAD.

The Spectrum of Non-asthmatic Airway Diseases Contributing to Cough in the Adult

PURPOSE OF REVIEW

Cough becomes a pathologic reflex when the airways are inflamed and overwhelmed with excessive mucus. The goal of this review is to discuss acute and chronic cough syndromes caused by non-asthmatic airway diseases.

RECENT FINDINGS

Acute cough syndrome is short-lived and self-limited. Acute bronchitis and diffuse acute infectious bronchiolitis (DAIB) are examples. The former is usually caused by a viral illness; the latter by Mycoplasma pneumoniae, influenza, and Haemophilus influenzae. Causes of chronic cough in the adult include chronic bronchitis, non-infectious bronchiolitis, and non-cystic fibrosis bronchiectasis.

SUMMARY

Supportive measures are recommended for acute bronchitis and antibiotic use is discouraged. Antibiotics may be needed for DAIB. Smoking cessation and bronchodilators can control cough in chronic bronchitis. Therapeutic approaches for non-infectious bronchiolitis depend on the varied etiology. The hallmark of bronchiectasis is a chronic infection of the airways, and antibiotics, mucus clearance measures, and bronchodilators are all supportive.

Perspectives in veterinary medicine: Description and classification of bronchiolar disorders in cats

This Perspectives in Veterinary Medicine article seeks to define, describe putative causes, and discuss key diagnostic tests for primary and secondary bronchiolar disorders to propose a classification scheme in cats with support from a literature review and case examples. The small airways (bronchioles with inner diameters <2 mm), located at the transitional zone between larger conducting airways and the pulmonary acinus, have been overlooked as major contributors to clinical syndromes of respiratory disease in cats. Because the trigger for many bronchiolar disorders is environmental and humans live in a shared environment with similar susceptibility, understanding these diseases in pet cats has relevance to One Health. Thoracic radiography, the major imaging modality used in the diagnostic evaluation of respiratory disease in cats, has low utility in detection of bronchiolar disease. Computed tomography (CT) with paired inspiratory and expiratory scans can detect pathology centered on small airways. In humans, treatment of bronchiolar disorders is not well established because of heterogeneous presentations and often late definitive diagnosis. A review of the human and veterinary medical literature will serve as the basis for a proposed classification scheme in cats. A case series of cats with CT or histopathologic evidence of bronchiolar lesions or both, either as a primary disorder or secondary to extension from large airway disease or interstitial lung disease, will be presented. Future multi‐institutional and multidisciplinary discussions among clinicians, radiologists, and pathologists will help refine and develop this classification scheme to promote early and specific recognition and optimize treatment.

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.

Analysis of pulmonary features and treatment approaches in the COPA syndrome

The COPA syndrome is a monogenic, autoimmune lung and joint disorder first identified in 2015. This study sought to define the main pulmonary features of the COPA syndrome in an international cohort of patients, analyse patient responses to treatment and highlight when genetic testing should be considered.

We established a cohort of subjects (N=14) with COPA syndrome seen at multiple centres including the University of California, San Francisco, CA, USA. All subjects had one of the previously established mutations in the COPA gene, and had clinically apparent lung disease and arthritis. We analysed cohort characteristics using descriptive statistics.

All subjects manifested symptoms before the age of 12 years, had a family history of disease, and developed diffuse parenchymal lung disease and arthritis. 50% had diffuse alveolar haemorrhage. The most common pulmonary findings included cysts on chest computed tomography and evidence of follicular bronchiolitis on lung biopsy. All subjects were positive for anti-neutrophil cytoplasmic antibody, anti-nuclear antibody or both and 71% of subjects had rheumatoid factor positivity. All subjects received immunosuppressive therapy.

COPA syndrome is an autoimmune disorder defined by diffuse parenchymal lung disease and arthritis. We analysed an international cohort of subjects with genetically confirmed COPA syndrome and found that common pulmonary features included cysts, follicular bronchiolitis and diffuse alveolar haemorrhage. Common extrapulmonary features included early age of onset, family history of disease, autoantibody positivity and arthritis. Longitudinal data demonstrated improvement on chest radiology but an overall decline in pulmonary function despite chronic treatment.

When to consider COPA syndrome, a Mendelian disorder with lung disease and arthritis, plus a review of treatments usedhttp://ow.ly/hWv130k21vT

Pulmonary Nodular Lymphoid Hyperplasia with Mass-Formation: Clinicopathologic Characteristics of Nine Cases and Review of the Literature

Background

Pulmonary nodular lymphoid hyperplasia (PNLH) is a non-neoplastic pulmonary lymphoid disorder that can be mistaken for malignancy on radiography. Herein, we present nine cases of PNLH, emphasizing clinicoradiological findings and histological features.

Methods

We analyzed radiological and clinicopathological features from the electronic medical records of nine patients (eight females and one male) diagnosed with PNLH. IgG and IgG4 immunohistochemical staining was performed in three patients.

Results

Two of the nine patients had experienced tuberculosis 40 and 30 years prior, respectively. Interestingly, none were current smokers, although two were ex-smokers. Three patients complaining of persistent cough underwent computed tomography of the chest. PNLH was incidentally discovered in five patients during examination for other reasons. The remaining patient was diagnosed with the disease following treatment for pneumonia. Imaging studies revealed consolidation or a mass-like lesion in eight patients. First impressions included invasive adenocarcinoma and mucosal-associated lymphoid tissue‒type lymphoma. Aspergillosis was suspected in the remaining patient based on radiological images. Resection was performed in all patients. Microscopically, the lesions consisted of nodular proliferation of reactive germinal centers accompanied by infiltration of neutrophils and macrophages in various degrees and surrounding fibrosis. Ultimately, all nine patients were diagnosed with PNLH and showed no evidence of recurrence on follow-up.

Conclusions

PNLH is an uncommon but distinct entity with a benign nature, and understanding the radiological and clinicopathological characteristics of PNLH is important.

The Clinical Characteristics and Outcomes of Follicular Bronchiolitis in Chinese Adult Patients

Follicular bronchiolitis (FB) is a rare interstitial lung disease (ILD) and has been reported in diverse clinical contexts. Six FB patients demonstrated by surgical lung biopsy (SLB) were reviewed between 2009 and 2017 from Nanjing Drum Tower Hospital in China. The average age of subjects was 42 years old (range: 31-55 years). The clinical symptoms were very mild. The laboratory findings showed elevated Erythrocyte sedimentation rate (ESR) and serum globulin and anemia. Pulmonary function tests were normal in four cases. Five cases had underlying diseases, such as, Sjo¨gren's syndrome, multi-centric castlemans' disease, idiopathic pneumonia with autoimmune features and abscess. Five cases presented as interstitial lung disease (ILD) on chest imaging with centrilobular or peribronchiolar nodules, ground glass opacities, interlobular septal thickening, cysts and bronchiectasis. Isolated mass was in one patient. The histopathology suggested the changes of FB in all subjects. Prednisone and/or cyclophosphamide were used in four cases, one did the surgery and the other was clinically monitored. All cases were alive at the end of follow up. The adult patients of FB usually have mild symptoms, ILD and underlying diseases. The definite diagnosis needs SLB. The prognosis is depended on their underlying conditions.

Follicular bronchiolitis in an HIV-infected individual on combination antiretroviral therapy with low CD4+ cell count but sustained viral suppression

A 36-year-old Danish man, living in Asia, was diagnosed with Pneumocystis pneumonia (PCP) and HIV in 2013 (CD4+ count: 6 cells/µL; viral load: 518 000 copies/mL). He initiated combination antiretroviral therapy. Later that year, he was also diagnosed with granulomatosis with polyangiitis and was treated with prednisolone. Despite complete viral suppression and increasing CD4+ count (162 cells/µL), he was readmitted with PCP in April 2015. Subsequently, he returned to Denmark (CD4+ count: 80 cells/µL, viral suppression). Over the following months, he developed progressive dyspnoea. Lung function tests demonstrated severely reduced lung capacity with an obstructive pattern and a moderately reduced diffusion capacity. High resolution computer tomography revealed minor areas with tree-in-bud pattern and no signs of air trapping on expiratory views. Lung biopsy showed lymphocytic infiltration surrounding the bronchioles with sparing of the alveolar septa. He was diagnosed with follicular bronchiolitis. The patient spontaneously recovered along with an improvement of the immune system.

COPA syndrome in an Icelandic family caused by a recurrent missense mutation in COPA

Background

Rare missense mutations in the gene encoding coatomer subunit alpha (COPA) have recently been shown to cause autoimmune interstitial lung, joint and kidney disease, also known as COPA syndrome, under a dominant mode of inheritance.

Case presentation

Here we describe an Icelandic family with three affected individuals over two generations with a rare clinical presentation of lung and joint disease and a histological diagnosis of follicular bronchiolitis. We performed whole-genome sequencing (WGS) of the three affected as well as three unaffected members of the family, and searched for rare genotypes associated with disease using 30,067 sequenced Icelanders as a reference population. We assessed all coding and splicing variants, prioritizing variants in genes known to cause interstitial lung disease. We detected a heterozygous missense mutation, p.Glu241Lys, in the COPA gene, private to the affected family members. The mutation occurred de novo in the paternal germline of the index case and was absent from 30,067 Icelandic genomes and 141,353 individuals from the genome Aggregation Database (gnomAD). The mutation occurs within the conserved and functionally important WD40 domain of the COPA protein.

Conclusions

This is the second report of the p.Glu241Lys mutation in COPA, indicating the recurrent nature of the mutation. The mutation was reported to co-segregate with COPA syndrome in a large family from the USA with five affected members, and classified as pathogenic. The two separate occurrences of the p.Glu241Lys mutation in cases and its absence from a large number of sequenced genomes confirms its role in the pathogenesis of the COPA syndrome.

Electronic supplementary material

The online version of this article (10.1186/s12881-017-0490-8) contains supplementary material, which is available to authorized users.

Systemic manifestations of primary Sjögren's syndrome in the NOD.B10Sn-H2b/J mouse model

Animal models that recapitulate human disease are crucial for the study of Sjögren's Syndrome (SS). While several SS mouse models exist, there are few primary SS (pSS) models that mimic systemic disease manifestations seen in humans. Similar to pSS patients, NOD.B10Sn-H2^b/J (NOD.B10) mice develop exocrine gland disease and anti-nuclear autoantibodies. However, the disease kinetics and spectrum of extra-glandular disease remain poorly characterized in this model. Our objective was to characterize local and systemic SS manifestations in depth in NOD.B10 female mice at early and late disease time points. To this end, sera, exocrine tissue, lung, and kidney were analyzed. NOD.B10 mice have robust lymphocytic infiltration of salivary and lacrimal tissue. In addition, they exhibit significant renal and pulmonary inflammation. We identified numerous autoantibodies, including those directed against salivary proteins. In conclusion, the NOD.B10 model recapitulates both local and systemic pSS disease and represents an excellent model for translational studies.

Copa Syndrome: a Novel Autosomal Dominant Immune Dysregulatory Disease

Inherently defective immunity typically results in either ineffective host defense, immune regulation, or both. As a category of primary immunodeficiency diseases, those that impair immune regulation can lead to autoimmunity and/or autoinflammation. In this review we focus on one of the most recently discovered primary immunodeficiencies that leads to immune dysregulation: "Copa syndrome". Copa syndrome is named for the gene mutated in the disease, which encodes the alpha subunit of the coatomer complex-I that, in aggregate, is devoted to transiting molecular cargo from the Golgi complex to the endoplasmic reticulum (ER). Copa syndrome is autosomal dominant with variable expressivity and results from mutations affecting a narrow amino acid stretch in the COPA gene-encoding COPα protein. Patients with these mutations typically develop arthritis and interstitial lung disease with pulmonary hemorrhage representing a striking feature. Immunologically Copa syndrome is associated with autoantibody development, increased Th17 cells and pro-inflammatory cytokine expression including IL-1β and IL-6. Insights have also been gained into the underlying mechanism of Copa syndrome, which include excessive ER stress owing to the impaired return of proteins from the Golgi, and presumably resulting aberrant cellular autophagy. As such it represents a novel cellular disorder of intracellular trafficking associated with a specific clinical presentation and phenotype.