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

Rheumatoid arthritis extra-articular lung disease: new insights on pathogenesis and experimental drugs

INTRODUCTION

Pulmonary involvement is one of the most common extra-articular manifestations of rheumatoid arthritis (RA), a systemic inflammatory disease characterized by joint swelling and tenderness. All lung compartments can be interested in the course of RA, including parenchyma, airways, and, more rarely, pleura and vasculature.

AREAS COVERED

The aim of this paper is to review the main RA lung manifestations, focusing on pathogenesis, clinical and therapeutic issues of RA-related interstitial lung disease (ILD). Despite an increasing number of studies in the last years, pathogenesis of RA-ILD remains largely debated and the treatment of RA patients with lung involvement is still challenging in these patients.

EXPERT OPINION

Management of RA-ILD is largely based on expert-opinion. Due to the broad clinical manifestations, including both joints and pulmonary involvement, multidisciplinary discussion, including rheumatologist and pulmonologist, is essential, not only for diagnosis, but also to evaluate the best therapeutic approach and follow-up. In fact, the coexistence of different lung manifestations may influence the treatment response and safety. The identification of biomarkers and risk-factors for an early identification of RA patients at risk of developing ILD remains a need that still needs to be fulfilled, and that will require further investigation in the next years.

Imaging of Small Airways Disease

Bronchiolitis refers to a small airways disease and may be classified by etiology and histologic features. In cellular bronchiolitis inflammatory cells involve the small airway wall and peribronchiolar alveoli and manifest on CT as centrilobular nodules of solid or ground glass attenuation. Constrictive bronchiolitis refers to luminal narrowing by concentric fibrosis. Direct CT signs of small airway disease include centrilobular nodules and branching tree-in-bud opacities. An indirect sign is mosaic attenuation that may be exaggerated on expiratory CT and represent air trapping. Imaging findings can be combined with clinical and pathologic data to facilitate a more accurate diagnosis.

Airway Disease in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a common condition affecting approximately 1% of the general population. RA is a multisystem disorder that causes progressive articular destruction through synovial inflammation. One of the most common extraarticular manifestations of RA is pulmonary involvement, where all compartments of the pulmonary system can be impacted (e.g., pulmonary vasculature, pleura, parenchyma, and the airways). Although it has been known for decades that a portion of patients with RA develop interstitial lung disease, and recent advancements in understanding the genetic risk and treatment for RA-interstitial lung disease have drawn attention, more recent data have begun to highlight the significance of airway disease in patients with RA. Yet, little is known about the underlying pathogenesis, clinical impact, or optimal treatment strategies for airway disease in RA. This review will focus on airway disease involvement in patients with RA by highlighting areas of clinical inquiry for pulmonologists and rheumatologists and discuss areas for future research. Finally, we discuss a potential screening algorithm for providers when approaching patients with RA with respiratory complaints.

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.

Birt-Hogg-Dubé syndrome

Birt–Hogg–Dubé syndrome (BHD) is a rare inherited autosomal dominant disorder caused by germline mutations in the tumour suppressor gene FLCN, encoding the protein folliculin. Its clinical expression typically includes multiple pulmonary cysts, recurrent spontaneous pneumothoraces, cutaneous fibrofolliculomas and renal tumours of various histological types. BHD has no sex predilection and tends to manifest in the third or fourth decade of life. Multiple bilateral pulmonary cysts are found on chest computed tomography in >80% of patients and more than half experience one or more episodes of pneumothorax. A family history of pneumothorax is an important clue, which suggests the diagnosis of BHD. Unlike other cystic lung diseases such as lymphangioleiomyomatosis and pulmonary Langerhans cell histiocytosis, BHD does not lead to progressive loss of lung function and chronic respiratory insufficiency. Renal tumours affect about 30% of patients during their lifetime, and can be multiple and recurrent. The diagnosis of BHD is based on a combination of genetic, clinical and/or skin histopathological criteria. Management mainly consists of early pleurodesis in the case of pneumothorax, periodic renal imaging for tumour detection, and diagnostic work-up in search of BHD in relatives of the index patient.

Birt–Hogg–Dubé syndrome is a rare genetic disorder characterised by multiple lung cysts, recurrent pneumothoraces, skin lesions and kidney tumours. As the presenting symptoms may be respiratory, chest physicians should be able to identify this disease.https://bit.ly/2xsOTuk

Pulmonary Involvement in Sjögren Syndrome

Sjögren syndrome (SS) is a progressive autoimmune disease characterized by dryness, predominantly of the eyes and mouth, caused by chronic lymphocytic infiltration of the lacrimal and salivary glands. Extraglandular inflammation can lead to systemic manifestations, many of which involve the lungs. Studies in which lung involvement is defined as requiring the presence of respiratory symptoms and either radiograph or pulmonary function test abnormalities quote prevalence estimates of 9% to 22%. The most common lung diseases that occur in relation to SS are airways disease and interstitial lung disease. Evidence-based guidelines to inform treatment recommendations for lung involvement are largely lacking.