Constrictive (obliterative) bronchiolitis

Case Report: Flavoring-Related Lung Disease in a Coffee Roasting and Packaging Facility Worker With Unique Lung Histopathology Compared With Previously Described Cases of Obliterative Bronchiolitis

Occupational exposure to diacetyl, a butter flavor chemical, can result in obliterative bronchiolitis. Obliterative bronchiolitis is characterized by exertional dyspnea, fixed airflow obstruction, and histopathologic constrictive bronchiolitis, with bronchiolar wall fibrosis leading to luminal narrowing and obliteration. We describe a case of advanced lung disease with histopathology distinct from obliterative bronchiolitis in a 37-year-old male coffee worker following prolonged exposure to high levels of diacetyl and the related compound 2,3-pentanedione, who had no other medical, avocational, or occupational history that could account for his illness. He began working at a coffee facility in the flavoring room and grinding area in 2009. Four years later he moved to the packaging area but continued to flavor and grind coffee at least 1 full day per week. He reported chest tightness and mucous membrane irritation when working in the flavoring room and grinding area in 2010. Beginning in 2014, he developed dyspnea, intermittent cough, and a reduced sense of smell without a work-related pattern. In 2016, spirometry revealed a moderate mixed pattern that did not improve with bronchodilator. Thoracoscopic lung biopsy results demonstrated focal mild cellular bronchiolitis and pleuritis, and focal peribronchiolar giant cells/granulomas, but no evidence of constrictive bronchiolitis. Full-shift personal air-samples collected in the flavoring and grinding areas during 2016 measured diacetyl concentrations up to 84-fold higher than the recommended exposure limit. Medical evaluations indicate this worker developed work-related, airway-centric lung disease, most likely attributable to inhalational exposure to flavorings, with biopsy findings not usual for obliterative bronchiolitis. Clinicians should be aware that lung pathology could vary considerably in workers with suspected flavoring-related lung disease.

Obliterative bronchiolitis associated with rheumatoid arthritis: analysis of a single-center case series

BACKGROUND

Rheumatoid arthritis (RA) is a systemic autoimmune condition characterized by erosive inflammation of the joints. One rare pulmonary manifestation is obliterative bronchiolitis (OB), a small airways disease characterized by the destruction of bronchiolar epithelium and airflow obstruction.

METHODS

We retrospectively reviewed the clinical data of patients with rheumatoid arthritis-associated obliterative bronchiolitis (RA-OB) from 01/01/2000 to 12/31/2015. Presenting clinical features, longitudinal pulmonary function testing, radiologic findings, and independent predictors of all-cause mortality were assessed.

RESULTS

Forty one patients fulfilled criteria for diagnosis of RA-OB. There was notable female predominance (92.7%) with a mean age of 57 ± 15 years. Dyspnea was the most common presenting clinical symptom. Median FEV1 was 40% (IQR 31-52.5) at presentation, with a mean decline of - 1.5% over a follow-up period of thirty-three months. Associated radiologic findings included mosaic attenuation and pulmonary nodules. A majority of patients (78%) received directed therapy including long-acting inhalers, systemic corticosteroids or other immunosuppressive agents, and macrolide antibiotics. All-cause mortality was 27% over a median follow-up of sixty-two months (IQR 32-113). No distinguishable predictors of survival at presentation were found.

CONCLUSIONS

RA-OB appears to have a stable clinical course in the majority of patients despite persistent symptoms and severe obstruction based on presenting FEV1.

Bronchiolitis obliterans murine model induced by nitric acid aerosol inhalation: An economical and reproducible model

PURPOSE

Bronchiolitis obliterans (BO) is a highly debilitative and fatal syndrome associated with a series of severe lower airway disorders. The pathogenesis of BO is complicated and not entirely understood. An appropriate animal model of BO may aid research into its pathogenesis. Here, we establish a mouse model of BO to provide insight into this disease.

MATERIALS AND METHODS

6-8 week old BABL/c mice were exposed to 5% nitric acid (NA) aerosol through a nebulizer for 3 hours, and controls were exposed to distilled water instead. Symptoms, airway resistance and pathological process were observed dynamically. The levels of matrix metalloproteinase-2 (MMP-2), MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), 8-isoprostane and myeloperoxidase (MPO) in lung tissue and bronchoalveolar lavage fluids (BLAF) were determined by ELISA on day 3, 7, 14, 28 and 56 after the aerosol nebulization.

RESULTS

Typical BO lesions were observed in NA nebulized mice characterized histologically by initial necrotizing bronchiolitis and final airway fibrosis at day 28 after the aerosol nebulization. NA nebulized mice also exhibited labored breathing and significantly increased airway resistance. Expression of MMP-2, MMP-9, TIMP-1, 8-isoprostane and MPO were significantly elevated in NA nebulized mice in different time frame.

CONCLUSION

A murine BO model was established by NA aerosol inhalation. It provides an easy, economic, and reproducible mice model for BO research.

VATS bullectomy and apical pleurectomy for spontaneous pneumothorax in a young patient with Swyer-James-Mc Leod syndrome: case report presentation and literature review focusing on surgically treated cases

BACKGROUND

Swyer-James-McLeod Syndrome (SJMS) is an uncommon, emphysematous disease characterized by radiologic hyperlucency of pulmonary parenchyma due to loss of the pulmonary vascular structure and to alveolar overdistension.

CASE REPORT

We herein describe a 15-year-old Caucasian patient with well-established SJMS since childhood who presented with spontaneous pneumothorax. Video-assisted thoracoscopic bullectomy with apical pleurectomy was performed. Since SJMS is considered an on-going inflammatory process, the patient one year after surgery exhibits excellent quality of life with no pneumothorax recurrence.

Pulmonary manifestations of rheumatoid arthritis

Pulmonary disease is a major source of morbidity and mortality in rheumatoid arthritis, manifesting most commonly as interstitial lung disease, airways disease, rheumatoid nodules, and pleural effusions. The diagnostic assessment of respiratory abnormalities is complicated by underlying risk for infection, the use of drugs with known pulmonary toxicity, and the frequency of lung disease related to rheumatoid arthritis itself. Evaluation and management of rheumatoid arthritis-associated pulmonary disease frequently necessitates a multidisciplinary approach.

Swyer-James-MacLeod syndrome; repeated chest drainages in a patient misdiagnosed with pneumothorax

Swyer-James-MacLeod Syndrome (SJMS) occurs as a result of childhood bronchiolitis obliterans. Typically, this disorder is diagnosed in childhood after evaluations for recurrent respiratory infections. One of the reasons to explain the difficulty in diagnosis is that when patients develop little bronchiectasis, and therefore, few symptoms, then this syndrome may not be recognized until adulthood. Here, we are presenting a 22-year-old female patient who was diagnosed with SJMS who was initially misdiagnosed with a pneumothorax and treated by multiple chest tube drainages. This case highlights the significance of taking a careful history, the application of computed tomography and scintigraphy in confirming the diagnosis of SJMS and in eliminating other diseases.

A prospective study of respiratory ciliary structure and function after stem cell transplantation

We prospectively investigated the morphological and ciliary function abnormalities in 19 consecutive Chinese patients undergoing hemopoietic stem cell transplantation (HSCT) and studied their relationship with pulmonary complications. The percentage of structural ciliary abnormalities preceding HSCT was comparable to normal controls, but increased up to 1-year post-HSCT. However, the abnormalities did not correlate with ciliary or pulmonary function. Ciliary beat frequency (CBF) for patients undergoing autologous and allogeneic SCT was lower than that of matched controls, with a further decline at one year. There was, however, no significant change in pulmonary function for the whole cohort. There was considerable variation in CBF and ciliary abnormalities in all cases during 3-month interval assessments. Regular ciliary assessment did not predict the only two patients who eventually suffered from bronchiolitis obliterans (BO). We conclude that structural and functional ciliary abnormalities are common in recipients of HSCT, and predict post-HSCT deterioration. However, there is no evidence to show that CBF monitoring may be of prospective benefit.

The Organizing Pneumonias

In this comprehensive review, two very closely related interstitial pneumonias are discussed: the cryptogenic form of organizing pneumonia (COP); and secondary forms of organizing pneumonia (OP), which occur in association with identifiable medical conditions. Some newer and lesser known of these associated conditions are described, most importantly post-radiation OP.Rapidly progressive, corticosteroid-resistant and poor prognostic forms of OP have been described. These types purportedly occur more frequently in secondary OP. However, OPs frequently coexist with other interstitial pneumonias, especially when associated with connective tissue diseases. Therefore, tissue sampling error or an incorrect morphologic diagnosis can be the basis for the occurrence of clinically aggressive OPs. By using the 2002 American Thoracic Society/European Respiratory Society diagnostic criteria, some pre-2002 cases reported as OP would be re-classified today.Although COP is considered to have a good prognosis and to be corticosteroid responsive, approximately 70% of patients, treated with corticosteroids, relapse even during initial treatment. Multiple and late relapses occur in about one-third of the patients. We performed a meta-analysis of second-line treatment options for corticosteroid-refractory forms of OP. Three alternative nonsteroid agents - cyclophosphamide, azathioprine, and cyclosporin - have been used in combination with corticosteroids. On careful review, in a number of cases reported as secondary OP, other histologic interstitial patterns besides OP were described. The need for second-line therapy in these patients might have been dictated by the non-organizing pneumonic component. Most of the scant number of reports come from outside the US. World experience with these is limited, but good clinical outcomes have been noted, even in patients with interstitial patterns in addition to OP.The initiation of the OP tissue response in the bronchiolar and sub-bronchiolar location may be due to the presence of bronchiolar-associated lymphoid tissue found at the bifurcations of the bronchioles. Inhaled antigens stimulate granulocyte colony stimulating factor-mediated airway inflammation, followed later by CD44-mediated clearance. Repair requires intrabronchiolar formation of granulation tissue and a favorable ratio of matrix metalloproteinase to tissue inhibitors of metalloproteinase (MMP : TIMP) within the stroma. This reparative milieu allows extracellular matrix degradation and re-synthesis to occur. MMP-expressing fibroblasts then phagocytose the collagen fibrils and microfibrils produced earlier in repair, reversing the initial fibrosis.

The organizing pneumonias: an update and review

PURPOSE OF REVIEW

Basic information as well as more recent concepts regarding cryptogenic organizing pneumonia and secondary forms of the disease.

RECENT FINDINGS

More recently described and less well recognized illnesses associated with organizing pneumonia, such as organizing pneumonia associated with radiation, are enumerated. In vitro studies from separate laboratories are integrated to create a proposed model of the pathogenesis and repair mechanisms that occur in organizing pneumonias. Using current criteria, we note other interstitial lung processes, in addition to organizing pneumonia, are present in some earlier reports.

SUMMARY

Cryptogenic organizing pneumonia has been reported to respond to corticosteroids with clinico-radiographic resolution in 70-80% of cases. Treatment duration is lengthy, and despite this, recurrences and late recurrences are common. Rapidly progressive, steroid resistant and poor prognostic forms of organizing pneumonia have been described and have been reported more frequently with secondary organizing pneumonia. Since other histologic interstitial patterns often coexist with organizing pneumonia, tissue sampling error or an incorrect morphologic diagnosis can be the reason for aggressive clinical behavior. Steroid nonresponsive patients have been treated with secondary non-steroidal agents. Good clinical outcomes have been reported. Inhaled antigens stimulate GM-CSF-mediated airway inflammation in organizing pneumonia. Repair requires the following: granulation tissue, upon which re-epithelialization occurs; a favorable stromal ratio of matrix metalloproteinase to tissue inhibitors of metalloproteinase; concurrent resolution of inflammation; and stromal fibroblast ingestion of collagen produced earlier in repair, reversing the initial fibrosis.

[A child with pulmonary hypertension: from etiological study to therapeutic decisions]

Pulmonary hypertension is a rare but devastating disease, with poor prognosis and high mortality. The disease may present as Primary Pulmonary Hypertension where no clear aetiology can be identified, or be related to a variety of underlying conditions. This is a rare disease in paediatric age. The authors present the clinical case of a 4 years old child, admitted in Paediatric Department of S. João Hospital for syncope episode. The diagnosis of pulmonary hypertension was made by echocardiogram. Ulterior studies revealed pulmonary disease (obliterans bronchiolitis). The treatment included a calcium channel blocker (diltiazem), an endothelin antagonist (bosentan) and supplemental oxygen. This is the first case of obliterans bronchiolitis diagnosed during etiological study for pulmonary hypertension, in our Pediatrics Department. In this case we could not determine the pulmonary disease precipitating event.

Effects of childhood respiratory diseases on the anatomical and functional development of the respiratory system

The anatomical and functional development of the lung appears especially vulnerable to a whole range of insults during gestation and the first few years of life. A significant proportion of adult lung disease originates in utero or early infancy. Most publications on this topic are descriptive retrospective studies. An important limitation of these is that structural changes may precede abnormalities in lung function and development of symptoms. Little is known with certainty with respect to the long-term effects of early insults to the respiratory system. Furthermore, the reversibility of the functional and/or structural defects is hardly ever adequately investigated and it is probably not correct to extrapolate findings from adult studies to paediatric pulmonary diseases. Promoting or facilitating optimal lung growth in fetuses and infants and reducing the incidence of lower respiratory tract infection in infancy may reduce the incidence of adult chronic lung disease in generations to come.

Effects of linear polyethylenimine and polyethylenimine/DNA on lung function after airway instillation to rat lungs

Lung transplantation is an acceptable treatment option for various end-stage pulmonary diseases, but long-term survival currently lags behind that after transplantation of other solid organs. We hypothesized that gene transfer to grafts before transplantation may be a useful method to deliver antioxidant and/or anti-inflammatory genes to modulate these processes. For this purpose, we assessed the efficiency of gene transfer and effects on lung function of the synthetic polycation, linear polyethylenimine (PEI), after airway instillation to the lungs of Fischer rats. Twenty-four hours after gene delivery, reporter gene activity in DNA/PEI treated rats was approximately 12-fold higher than that in rats treated with naked DNA, but by 72 hours there was no significant difference between groups and activity had decreased by at least 85%. Function of the transfected left lung was assessed by measuring arterial PaO(2) levels and was found to be significantly lower at 24 and 72 hours after gene transfer in the PEI/DNA group compared with the naked DNA group. The deterioration in lung function correlated with histological findings. Rats treated with PEI alone and sacrificed after 72 hours showed an impairment in lung function similar to that seen with PEI/DNA treatment. Our studies highlight the importance of assessing the functional capacity of a graft after gene transfer to determine suitability for subsequent transplantation.

Respiratory ciliary function in bone marrow recipients

Bone marrow transplantation (BMT) recipients, particularly those with chronic graft-versus-host disease (GVHD), suffer from respiratory tract problems, including bronchiolitis obliterans (BO) and recurrent lower respiratory tract infections. Minute cilia beat continuously on the surface of respiratory mucosa, and this beating maintains the sterility of the lower respiratory tract. Dysfunction of respiratory cilia could lead to development of recurrent respiratory tract infections, which are also features of BMT recipients, although ciliary function has not been systematically studied among these subjects. We have, therefore, investigated the ciliary beat frequency (CBF) of 36 Chinese patients who had undergone allogeneic BMT. The CBF was significantly lower in the BMT group compared to controls (P < 0.001). The reduction in CBF was more severe in patients with cGVHD and BO compared with their counterparts (P = 0.048 and P = 0.077, respectively). There was a correlation between CBF with forced expiratory flow rate FEF (P = 0.024) and forced expiratory volume FEV (P = 0.044). We conclude that abnormal ciliary clearance is a common feature after allogeneic BMT, particularly among patients with BO and cGVHD. Further studies are indicated to evaluate this important phenomenon, which could be an important cause of the susceptibility for BMT recipients to respiratory infections.