Bronchiolitis obliterans organizing pneumonia: definition and clinical features

Pulmonary Toxicities of Immunotherapy

Immune checkpoint inhibitors are a form of immunotherapy that are increasingly being used in a wide variety of cancers. Immune-related adverse events (irAEs) pose a major challenge in the treatment of cancer patients. Pneumonitis, the most common lung irAE, can cause significant disruptions in the treatment of cancer and may be life-threatening. The goal of this chapter is to instruct readers on the incidence and clinical manifestations of pneumonitis and to offer guidance in the evaluation and treatment of patients with pneumonitis.

Pulmonary adverse events due to immune checkpoint inhibitors: A literature review

Cancer immunotherapy aims to stimulate the immune system to fight against tumors, utilizing the presentation of molecules on the surface of the malignant cells that can be recognized by the antibodies of the immune system. Immune checkpoint inhibitors, a type of cancer immunotherapy, are broadly used in different types of cancer, improving patients' survival and quality of life. However, treatment with these agents causes immune-related toxicities affecting many organs. The most frequent pulmonary adverse event is pneumonitis representing a non-infective inflammation localized to the interstitium and alveoli. Other lung toxicities include airway disease, pulmonary vasculitis, sarcoid-like reactions, infections, pleural effusions, pulmonary nodules, diaphragm myositis and allergic bronchopulmonary aspergillosis. This review aims to summarize these pulmonary adverse events, underlining the significance of an optimal expeditious diagnosis and management.

Cryobiopsy in the diagnosis of bronchiolitis: a retrospective analysis of twenty-three consecutive patients

Bronchiolitis manifests as a variety of histological features that explain the complex clinical profiles and imaging aspects. In the period between January 2011 and June 2015, patients with a cryobiopsy diagnosis of bronchiolitis were retrospectively retrieved from the database of our institution. Clinical profiles, imaging features and histologic diagnoses were analysed to identify the role of cryobiopsy in the diagnostic process. Twenty-three patients with a multidisciplinary diagnosis of small airway disease were retrieved (14 females, 9 males; age range 31-74 years old; mean age 54.2 years old). The final MDT diagnoses were post-infectious bronchiolitis (n = 5), constrictive bronchiolitis (n = 3), DIPNECH (n = 1), idiopathic follicular bronchiolitis (n = 3), Sjogren's disease (n = 1), GLILD (n = 1), smoking-related interstitial lung disease (n = 6), sarcoid with granulomatous bronchiolar disorder (n = 1), and subacute hypersensitivity pneumonitis (n = 2). Complications reported after the cryobiopsy procedure consisted of two cases of pneumothorax soon after the biopsy (8.7%), which were successfully managed with the insertion of a chest tube. Transbronchial cryobiopsy represents a robust and mini-invasive method in the characterization of small airway diseases, allowing a low percentage of complications and good diagnostic confidence.

Immune-Related Adverse Events: Pneumonitis

Checkpoint inhibitors are part of the family of immunotherapies and are increasingly being used in a wide variety of cancers. Immune-related adverse events pose a major challenge in the treatment of cancer patients. Pneumonitis is a rare immune-related adverse event that presents in distinct patterns. The goal of this chapter is to instruct readers on the incidence and clinical manifestations of pneumonitis and to offer guidance in the evaluation and treatment of patients with pneumonitis.

Bronchiolitis Obliterans Organizing Pneumonia as an Initial Presentation of Systemic Lupus Erythematosus: A Rare Case Report and Literature Review

The etiology of bronchiolitis obliterans organizing pneumonia (BOOP) remains controversial. While it has been reportedly associated with several connective tissue disorders, there are only rare reports of BOOP associated with systemic lupus erythematosus (SLE). Herein, we report a 56-year-old female patient who presented with dyspnea on exertion, cough, fever, and joint pain of her left wrist and fingers as initial symptoms. Laboratory tests revealed positivity for anti-nuclear antibody, anti-Ro, and anti-double strand DNA antibody. In this case, the patient with SLE had respiratory illness as the initial symptom due to BOOP in the absence of clear etiology. The diagnosis of BOOP was confirmed by thoracic surgery biopsy. Her respiratory symptoms and radiologic findings significantly improved following prednisolone treatment.

Pathology, toxicology, and latency of irritant gases known to cause bronchiolitis obliterans disease: Does diacetyl fit the pattern?

Bronchiolitis obliterans (BO) is a rare disease involving concentric bronchiolar fibrosis that develops rapidly following inhalation of certain irritant gases at sufficiently high acute doses. While there are many potential causes of bronchiolar lesions involved in a variety of chronic lung diseases, failure to clearly define the clinical features and pathological characteristics can lead to ambiguous diagnoses. Irritant gases known to cause BO follow a similar pathologic process and time course of disease onset in humans. Studies of inhaled irritant gases known to cause BO (e.g., chlorine, hydrochloric acid, ammonia, nitrogen oxides, sulfur oxides, sulfur or nitrogen mustards, and phosgene) indicate that the time course between causal chemical exposures and development of clinically significant BO disease is typically limited to a few months. The mechanism of toxic action exerted by these irritant gases generally involves widespread and severe injury of the epithelial lining of the bronchioles that leads to acute respiratory symptoms which can include lung edema within days. Repeated exposures to inhaled irritant gases at concentrations insufficient to cause marked respiratory distress or edema may lead to adaptive responses that can reduce or prevent severe bronchiolar fibrotic changes. Risk of BO from irritant gases is driven substantially by toxicokinetics affecting concentrations occurring at the bronchiolar epithelium. Highly soluble irritant gases that cause BO like ammonia generally follow a threshold-dependent cytotoxic mechanism of action that at sufficiently high doses results in severe inflammation of the upper respiratory tract and the bronchiolar epithelium concurrently. This is followed by acute respiratory distress, pulmonary edema, and post inflammatory concentric fibrosis that become clinically obvious within a few months. In contrast, irritant gases with lower solubility like phosgene also follow a threshold-dependent mechanism of cytotoxicity action but can exhibit more insidious and isolated bronchiolar tissue damage with a similar latency to fibrosis. To date, animal and human studies on the highly soluble gas, diacetyl, have not identified a coherent pattern of pathology and latency that would be expected based on studies of other known causes of bronchiolitis obliterans disease.

Intravenous immune globulins (IVIg) treatment for organizing pneumonia in a selective IgG immune deficiency state

We describe herein a 61-year-old woman who presented with fever, night sweats and cough. The diagnosis of pneumonia was established, but with symptom recurrence following antibiotic therapy, further diagnostics were performed. Biopsy via bronchoscopy revealed cryptogenic organizing pneumonia, and later on follow-up, a selective IgG immune deficiency was also diagnosed. Initial treatment of high-dose glucocorticoid therapy induced remission, but with dose reduction recurrence was observed. Intravenous immune globulin treatment was initiated and induced a successful clinical and radiological remission. Few cases of cryptogenic organizing pneumonia and hypogammaglobulinemia have been reported. To our knowledge, this is the fourth case described of cryptogenic organizing pneumonia with a hypogammaglobulinemia state and the first reported case of a selective immune deficiency state treated successfully with intravenous immune globulins.

Airspace-Occupying Diseases

Diseases of the air space of the lung share many common findings and presentation that it makes more sense to be grouped together in a differential diagnosis. The common imaging finding is usually as a lung infiltrate or consolidation of some type of distribution or another. Trying to find the putative cause for the imaging pattern is a good first step in narrowing the differential diagnosis and answering the question: what accounts for this pattern on imaging studies? Most of these diseases have an acute or subacute onset and exhibit restrictive pattern on pulmonary function tests. When treated promptly, they resolve completely with little or no residual injury to the lung architecture.

On a small biopsy it is important to have a clinical history and imaging results before embarking on a descriptive rather than a definitive diagnosis. The smaller the sample, the more information is needed to complete the picture. Pulmonologists should be advised to target the part of the lung that should provide the most information related to the process under investigation. An endobronchial wall biopsy is not suitable in the setting of investigating a lung infiltrate as part of the alveolated lung has to be included.

The category of airspace-occupying diseases of the lung includes:

Acute lung infections such as bacterial and viral pneumonias

Acute lung injury pattern which includes bronchiolitis obliterans/organizing pneumonia and diffuse alveolar damage

Intra-alveolar hemorrhage

Pulmonary alveolar proteinosis

Pulmonary edema

Pneumocystis pneumonia

Lymphangitic carcinomatosis

In all of these instances, there are ground-glass opacities obscuring the air space. Most clinicians would describe the imaging as “infiltrate” or “consolidation.” The task for the pathologist is to find the pertinent finding that could account for the imaging.

Nontuberculous mycobacterial lung disease accompanied by organizing pneumonia

We herein report our experience with patients who had nontuberculous mycobacterial lung disease (NTM disease) accompanied by organizing pneumonia (OP). Out of 98 NTM disease patients who had undergone a biopsy or surgical resection, 11 patients had OP that was revealed histologically. After excluding six patients who had OP-related diseases (idiopathic interstitial pneumonia, rheumatoid arthritis, etc.), the remaining five patients were studied. Two of them (a 73-year-old man and a 66-year-old woman) showed common clinical feature: acute-onset symptoms of cough and fever, infiltrating shadows and dramatic improvement following treatment with a corticosteroid and anti-mycobacterial therapy. Our cases demonstrate that NTM disease is sometimes accompanied by OP histologically, and some such cases show common clinical features.

Histologic Patterns of Acute Lung Injury and Issues in Forensic Medicine

Context

Acute lung injury and acute respiratory distress syndrome are significant causes of pulmonary morbidity and are frequently fatal. These two entities have precise definitions from a clinical standpoint. Histologically, cases from patients with clinical acute lung injury typically exhibit diffuse alveolar damage, but other histologic patterns may occasionally be encountered such as acute fibrinous and organizing pneumonia, acute eosinophilic pneumonia, and diffuse hemorrhage with capillaritis.

Objective

To review the diagnostic criteria for various histologic patterns associated with a clinical presentation of acute lung injury and to provide diagnostic aids and discuss the differential diagnosis.

Data Sources

The review is drawn from pertinent peer-reviewed literature and the author's personal experience.

Conclusions

Acute lung injury remains a significant cause of morbidity and mortality. The pathologist should be aware of histologic patterns of lung disease other than diffuse alveolar damage which are associated with a clinical presentation of acute lung injury. Identification of these alternate histologic findings as well as identification of potential etiologic agents, especially infection, may impact patient treatment and disease outcome.

Histopathologic approach to the surgical lung biopsy in interstitial lung disease

Interpretation of lung biopsy specimens is an integral part in the diagnosis of interstitial lung disease (ILD). The process of evaluating a surgical lung biopsy for disease involves answering several questions. Unlike much of surgical pathology of neoplastic lung disease, arriving at the correct diagnosis in nonneoplastic lung disease often requires correlation with clinical and radiologic findings. The topic of ILD or diffuse infiltrative lung disease covers several hundred entities. This article is meant to be a launching point in the clinician's approach to the histologic evaluation of lung disease.

Simultaneous diagnosis of cryptogenic organizing pneumonia and HIV in a 45 year old man

BACKGROUND

Cryptogenic organizing pneumonia (COP) is a small airways disease characterized by intraluminal polyps of myxoid connective tissue which follows a subclinical course and is associated with infectious as well as non infectious processes The concomitant occurrence of human immunodeficiency virus (HIV) infection and COP has rarely been reported. We describe a unique case in which COP was a presenting feature in a patient with newly diagnosed HIV Infection.

CASE REPORT

A 45 year-old man with chronic active smoking presented to the ER with 15 months history of cough productive of minimal whitish sputum without frank or streaks of blood, low grade fever, anorexia and 4-6 lbs weight loss in past 6 months. He had three life time sexual partners. PPD status were unknown. He was extensively worked up as the Chest X ray showed cystic lesions all of which came back normal. Patient also received HIV test which was positive with CD 4 count of 546. He received bronchoscopy which revealed cryptogenic organising pneumonia. He was placed on steroids tapering course which helped in relieving the symptoms.

CONCLUSIONS

HIV infection with CD 4 count above 500 has seldom been reported having COP with this case being the second in literature but this entity should be kept in mind during management of these patients.

Organising pneumonia presenting as acute life threatening pulmonary haemorrhage

Organising pneumonia, previously called bronchiolitis obliterans organising pneumonia is a clinicopathological entity of unknown aetiology, which has been reported with increasing frequency. Various modes of presentation have been described such as cough, fever, weight loss and alveolar opacities on chest radiograph. Haemoptysis as primary presenting symptom has only rarely been reported. The authors report a case in which massive life-threatening haemoptysis was the major presenting symptom. No aetiology was identified for the haemoptysis and the diagnosis was confirmed on postmortem histology. This case highlights the importance of considering organising pneumonia in the differential diagnosis of acute severe haemoptysis.

Interactive high-resolution computed tomography digital atlas of interstitial lung disease

High-resolution computed tomography is a necessary tool used in the diagnosis of interstitial lung disease. The interpretation of high-resolution computed tomography can be difficult given the wide spectrum of imaging appearances within the same disease and among different diseases. The authors provide a new educational method to learn about the spectrum of idiopathic interstitial lung disease through the use of a free online digital atlas and review article. This atlas can be downloaded at http://www.seattlechildrens.org/radiologyeducation/ILD.

Bronchiolitis obliterans organizing pneumonia in Swine associated with porcine circovirus type 2 infection

Bronchiolitis obliterans organizing pneumonia (BOOP) is a chronic respiratory disease. Although the pathogenesis of BOOP is still incompletely understood, BOOP is responsive to steroids and has a good prognosis. In our five pigs with chronic postweaning multisystemic wasting syndrome (PMWS), typical BOOP lesions were revealed. All five porcine lungs showed typical intraluminal plugs, and porcine circovirus type 2 (PCV2) was identified. They also exhibited similar pathologic findings such as proliferation of type II pneumocytes and myofibroblasts (MFBs), extracellular collagen matrix (ECM) deposition, and fragmentation of elastic fibers. MFBs migration correlative molecules, for instance, gelatinase A, B and osteopontin, appeared strongly in the progressing marginal area of polypoid intraluminal plugs of fibrotic lesion. These molecules colocalized with the active MFBs. Both gelatinase activity and intercellular level of active MFBs were significantly increased (P < .05). Porcine chronic bronchopneumonia leads to BOOP and it is associated with PCV2 persistent infection. Swine BOOP demonstrates similar cellular constituents with human BOOP. Perhaps their molecular mechanisms of pathogenesis operate in a similar way. Thus we infer that the swine BOOP can be considered as a potential animal model for human BOOP associated with natural viral infection. Moreover, it is more convenient to obtain samples.

Differential role of the Fas/Fas ligand apoptotic pathway in inflammation and lung fibrosis associated with reovirus 1/L-induced bronchiolitis obliterans organizing pneumonia and acute respiratory distress syndrome

Bronchiolitis obliterans organizing pneumonia (BOOP) and acute respiratory distress syndrome (ARDS) are two clinically and histologically distinct syndromes sharing the presence of an inflammatory and fibrotic component. Apoptosis via the Fas/Fas ligand (FasL) pathway plays an important role in the development of acute lung injury and fibrosis characteristic of these and other pulmonary inflammatory and fibrotic syndromes. We evaluated the role of apoptosis via the Fas/FasL pathway in the development of pulmonary inflammation and fibrosis in reovirus 1/L-induced BOOP and ARDS. CBA/J mice were intranasally inoculated with saline, 1 x 10(6) (BOOP), or 1 x 10(7) (ARDS) PFU reovirus 1/L, and evaluated at various days postinoculation for in situ apoptosis by TUNEL analysis and Fas/FasL expression. Our results demonstrate the presence of apoptotic cells and up-regulation of Fas/FasL expression in alveolar epithelium and in infiltrating cells during the inflammatory and fibrotic stages of both reovirus 1/L-induced ARDS and BOOP. Treatment of mice with the caspase 8 inhibitor, zIETD-fmk, inhibited apoptosis, inflammation, and fibrotic lesion development in reovirus 1/L-induced BOOP and ARDS. However, CBA/KlJms-Fas(lpr-cg)/J mice, which carry a point mutation in the Fas cytoplasmic region that abolishes the ability of Fas to transduce an apoptotic signal, do not develop pulmonary inflammation and fibrotic lesions associated with reovirus 1/L-induced BOOP, but still develop inflammation and fibrotic lesions associated with reovirus 1/L-induced ARDS. These results suggest a differential role for the Fas/FasL apoptotic pathway in the development of inflammation and fibrotic lesions associated with BOOP and ARDS.

Endogenous lung stem cells and contribution to disease

Epithelial branching during the process of lung development results in the establishment of distinct functional zones, each of which is characterized by a unique cellular composition and repertoire of local progenitor cells. Significant new insights into cellular and molecular mechanisms of epithelial maintenance that provide insights into the pathophysiology of lung disease have been made in recent years. This review focuses on the complex structure-function relationship in the airway epithelium, how this epithelium is maintained in the normal state and repaired following injury, and how deregulation may contribute to airway disease and cancer.

Monitoring of glucocorticoid therapy by assessment of CD14(+)CD16(+) monocytes: a case report

Bronchiolitis obliterans with organizing pneumonia (BOOP) is a disease affecting small airways and alveoli. It is characterized by interstitial inflammation rich in foamy macrophages and by fibroblastic connective tissue expanding into the airway and alveolar lumen. We report herein on a 54-year-old male BOOP patient who was treated with glucocorticoids (GCs) and who over a 5-year period had three relapses. At diagnosis the patient showed elevated CD14(+)CD16(+) monocyte numbers (85 cells/microl) and increased serum C-reactive protein (CRP) levels (29.4 mg/l). With GC therapy both parameters decreased within a few days. Diagnosis of relapse was preceded by a rise in CD14(+)CD16(+) monocyte numbers and in CRP levels which again responded to GC treatment. We conclude that determination of CD14(+)CD16(+) monocytes is a useful marker for monitoring of BOOP diagnosis and GC therapy.

Radiographic Appearance of Bronchiolitis Obliterans Organizing Pneumonia (BOOP) Developing During Bucillamine Treatment for Rheumatoid Arthritis

Bucillamine, a disease-modifying antirheumatic drug, can have adverse effects, including lung injury. Development of interstitial pneumonia during treatment for patients with rheumatoid arthritis (RA) can pose a difficult differential diagnosis between a direct manifestation of RA and a drug effect. Our review of previous reports suggested bucillamine-induced interstitial pneumonia in the patient described here, visualized by chest radiography and computed tomography based on patchy ground-glass opacities in a peribronchial or peripheral distribution, suggesting the appearance of bronchiolitis obliterans organizing pneumonia (BOOP). As is typical for BOOP, steroid responsiveness may have contributed to recovery.

[Differential diagnosis of bronchiectasis: high-resolution CT as a valuable aide]

Bronchiectasis is defined as localized irreversible dilatation of the bronchial tree. Brochiectasis has been associated with a wide variety of causes, but it is mostly caused by acute, chronic or recurrent infections. This paper should give a review about the manifestation of bronchiectasis and bronchioloectasis in HR-CT and discuss the causing entities. However, integration of bronchiectasis and other HR-CT findings may enable a narrower differential diagnosis, in some cases it is possible to give the correct diagnose directly.

[Cryptogenic organising pneumonia]

Organising Pneumonia (formerly called Bronchiolitis Obliterans with Organising Pneumonia) is a particular form of inflammatory and fibroproliferative lung disease. Its idiopathic form called Cryptogenic Organising Pneumonia, was recently defined by an ATS/ERS consensus conference. The disease onset is subacute with cough, dyspnea, fever, asthenia, weight loss, crackles, and elevation of biological inflammatory markers. Bronchoalveolar lavage reveals a mixed alveolitis with elevated lymphocyte, neutrophil, and eosinophil counts. Chest imaging usually shows multifocal alveolar opacities predominating in the subpleural regions, often with a migratory pattern. Lung biopsy reveals budding connective tissue filling the distal airspaces. Diagnosis is established by combining clinical, radiological and histological criteria. Similarities with other disease processes can lead to delayed or erroneous diagnosis. Most patients respond well to corticosteroid therapy. Relapses are frequent but can generally be controlled with moderate doses of prednisone and do not worsen the prognosis. The therapeutic strategy aims at reducing the steroid doses while maintaining an optimal disease control.

The significance of cathepsins, thrombin and aminopeptidase in diffuse interstitial lung diseases

To determine the significance of proteases in interstitial lung diseases, we examined the activity of cathepsins, thrombin, and aminopeptidase in bronchoalveolar lavage (BAL) fluid from patients with these disorders. Significantly increased activities of cathepsin H and aminopeptidase were detected in BAL fluid from patients with idiopathic pulmonary fibrosis (IPF), cryptogenic organizing pneumonia (COP), chronic eosinophilic pneumonia (CEP) and hypersensitivity pneumonitis (HP). Significantly higher activity of cathepsin B was found in BAL fluid from patients with CEP. The activity of thrombin was significantly higher in patients with IPF and CEP. In patients with IPF, there were significant correlations between neutrophil number and the activity of cathepsin B, cathepsin H or aminopeptidase. In patients with COP and HP, the activity of the proteases was significantly higher in patients with higher number of lymphocytes than in those with lower number of lymphocytes. The present study suggests that the activity of the proteases is a useful marker in activity of the interstitial lung diseases, and may have a role in the pathogenesis of these disorders.

Incidence of interstitial lung diseases in the south of Spain 1998-2000: the RENIA study

This study aims to describe the distribution of interstitial lung diseases (ILD) in the South of Spain.

METHODS

A prospective multicentre population-based registry was established in nine provinces in the south of Spain with a population of 6,848,243 during a 3-year period (1998-2000). The number of participant physicians was 36 among 29 public hospitals. The number of diagnoses recorded was 66, divided in eight categories and coded according to ICD-9. A consensus document was elaborated for the classification of diseases and their diagnostic criteria. The number of cases declared was analysed each 3 months and communicated to each one of the participants.

RESULTS

There were 744 cases of them registered with an annual incidence of 3.62 cases/ 100,000. 40.1% of diagnoses were biopsy confirmed. Men had a slightly higher incidence (4.18 cases/ 100,000/year) than women (3.07 cases/100,000/year). The most frequent diseases found were: idiopathic interstitial pneumonias (38.58%), ILD associated to systemic diseases (20.97%), and Sarcoidosis (11.69%). According to province distribution, most of the cases were grouped in an area between the provinces of Seville and Cordoba, which comprised more than 50% of cases.

CONCLUSIONS

The study of the incidence of ILD depicts an intermediate situation from previous studies on the incidence and distribution of this group of diseases.

Bronchiolar disorders

Bronchiolar abnormalities are relatively common and occur in a variety of clinical settings. Various histopathologic patterns of bronchiolar injury have been described and have led to confusing nomenclature with redundant and overlapping terms. Some histopathologic patterns of bronchiolar disease may be relatively unique to a specific clinical context but others are nonspecific with respect to either etiology or pathogenesis. Herein, we present a scheme separating (1) those disorders in which the bronchiolar disease is the predominant abnormality (primary bronchiolar disorders) from (2) parenchymal disorders with prominent bronchiolar involvement and (3) bronchiolar involvement in large airway diseases. Primary bronchiolar disorders include constrictive bronchiolitis (obliterative bronchiolitis, bronchiolitis obliterans), acute bronchiolitis, diffuse panbronchiolitis, respiratory bronchiolitis, mineral dust airway disease, follicular bronchiolitis, and a few other rare variants. Prominent bronchiolar involvement may be seen in several interstitial lung diseases, including hypersensitivity pneumonitis, respiratory bronchiolitis-associated interstitial lung disease, cryptogenic organizing pneumonia (idiopathic bronchiolitis obliterans organizing pneumonia), and pulmonary Langerhans' cell histiocytosis. Large airway diseases that commonly involve bronchioles include bronchiectasis, asthma, and chronic obstructive pulmonary disease. The clinical relevance of a bronchiolar lesion is best determined by identifying the underlying histopathologic pattern and assessing the correlative clinico-physiologic-radiologic context.

Respiratory reovirus 1/L induction of intraluminal fibrosis, a model of bronchiolitis obliterans organizing pneumonia, is dependent on T lymphocytes

Bronchiolitis obliterans organizing pneumonia (BOOP) is a clinical syndrome characterized by perivascular/peribronchiolar leukocyte infiltration leading to the development of intraalveolar fibrosis. We have developed an animal model of BOOP where CBA/J mice infected with 1 x 10(6) plaque-forming units (PFU) reovirus 1/L develop follicular bronchiolitis and intraalveolar fibrosis similar to human BOOP. In this report, we demonstrate a role for T cells in the development of intraluminal fibrosis associated with BOOP. Corticosteroid treatment of reovirus 1/L-infected mice both inhibited the development of fibrotic lesions when administered early in the time-course and promoted the resolution of fibrotic lesions when corticosteroid administration was delayed. Further, the depletion of either CD4(+) or CD8(+) T cells before reovirus 1/L infection also inhibited fibrotic lesion development. Both corticosteroid treatment and depletion of CD4(+) or CD8(+) T cells also resulted in decreased expression of the proinflammatory and profibrotic cytokines, interferon (IFN)-gamma and monocyte chemoattractant protein-1 (MCP-1). Further, treatment of mice with a neutralizing monoclonal antibody to IFN-gamma also significantly inhibited the development of fibrosis. Taken together, these results suggest a significant role for T cells in the development of reovirus 1/L-induced BOOP fibrotic lesions in CBA/J mice and suggests that T(H)1-derived cytokines, especially IFN-gamma, may play a key role in fibrotic lesion development.

VEGF and bFGF are highly expressed in intraluminal fibromyxoid lesions in bronchiolitis obliterans organizing pneumonia

Bronchiolitis obliterans organizing pneumonia (BOOP) and usual interstitial pneumonia (UIP) are fibrous pulmonary disorders in which new fibromyxoid connective tissue is formed in distal air spaces. In BOOP this tissue is susceptible to even complete reversal, but in UIP it participates in the remodelling of the interstitium. Our previous study showed that in BOOP this newly formed intraluminal tissue is more capillarized than in UIP. This paper studies the immunohistochemical expression of vascular endothelial growth factor (VEGF) and its receptors Flt-1 and Flk-1, and basic fibroblast growth factor (bFGF) in BOOP and UIP. It was hypothesized that there would be a difference in the expression of these angiogenic growth factors paralleling the difference in their capillarization. The results show that both VEGF and bFGF are widely expressed in BOOP and in UIP. It was shown with two different VEGF antibodies that its expression was more pronounced in the intraluminal fibromyxoid lesions in BOOP than in UIP (p<0.001 and 0.004, respectively). Similarly, bFGF also showed stronger espression in BOOP than in UIP (p<0.02) in these areas. The expression of Flt-1 and Flk-1 was in agreement with the expression of VEGF. It is concluded that the growth factors VEGF and bFGF may have an important role in the pathogenesis of BOOP and UIP; furthermore, their expression correlates with the angiogenic activity of the newly formed intraluminal fibromyxoid connective tissue in BOOP. Angiogenesis mediated by these growth factors may be one reason for the reversal of intraluminal fibromyxoid connective tissue in BOOP and for its good clinical outcome.

Slowly resolving and nonresolving pneumonia. Questions to ask when response is delayed

What is the proper course of action when pneumonia symptoms seem to linger? Is the disease running a typical course, or is further evaluation needed? Dr Johnson addresses these important questions with an outline of risk factors for delayed resolution and a detailed listing of diagnostic considerations. He also discusses reasonable timing of further studies and the usefulness of radiography and fiberoptic bronchoscopy.

Bronchiolar disease: spectrum and radiological findings

Two types of bronchiole, the terminal bronchiole and the respiratory bronchiole, have structural and functional differences. The former is characterized as a conducting airway and the latter is closely related to a gas-exchange function as it has numerous alveoli on the wall. Therefore, the diseases occurring at bronchiole demonstrate different pathological, radiological and clinical pictures depending on which bronchiole is mainly involved. The disease that mainly involves the conducting airway is appreciated as a small airway disease. Constrictive bronchiolitis is a well-recognized entity classified in this category. Whereas the disease mainly involves the respiratory bronchiole and distal alveolar space, it is recognized as an interstitial and parenchymal disease. BOOP or RB-ILD is classified in this category. These two types of bronchiolar diseases reveal the contrast clinical pictures, including incidence, causative disease, response to the treatment, prognosis, respiratory function test as well as the radiological findings. This pictorial essay will illustrate the radiological features of the varieties of bronchiolitis.

Intraluminal fibromyxoid lesions in bronchiolitis obliterans organizing pneumonia are highly capillarized

Bronchiolitis obliterans organizing pneumonia (BOOP) and usual interstitial pneumonia (UIP; ie, cryptogenic fibrosing alveolitis of mural type, CFA) are clinically and histologically distinguishable interstitial lung diseases. Both contain intraluminal lesions of newly formed fibromyxoid connective tissue. In BOOP, the fibromyxoid lesions are susceptible to complete reversal, but in UIP they are supposed to participate in the remodeling of the interstitium. Our hypothesis was that capillarization of the intraluminal fibromyxoid lesions is more frequent in BOOP compared with UIP. In this study, we stained diagnostic thoracoscopic or open lung biopsy specimens of patients with BOOP (n = 9) and UIP (n = 10) with antibodies against human laminin, von Willebrand factor, and CD34 to reveal the microvasculature of intraluminal fibromyxoid lesions. Our results show that in BOOP there is abundant capillarization in the newly formed intraluminal fibromyxoid lesions often reminiscent of granulation tissue. The mean number of capillaries per area unit (mm2) was 107 +/- SD 74 in samples stained for laminin, 103 +/- SD 46 for von Willebrand factor, and 63 +/- SD 36 for CD34. In marked contrast, in UIP, the corresponding accounts were significantly lower, being 14 +/- SD 15 for laminin (P < .003), 11 +/- SD 14 for von Willebrand factor (P < .001) and 6 +/- SD 6 for CD34 (P < .001). The intraobserver (P < .001) and interobserver correlations (P < .002) were highly significant, showing that our results are reproducible. We conclude that the content and nature of the newly formed intraluminal connective tissue, for example, in the form of vascular growth factors, are different in BOOP and in UIP, and this partly leads to the different clinical course of these diseases.

Idiopathic pulmonary fibrosis: current concepts

Idiopathic pulmonary fibrosis (IPF) is generally defined as a progressive, fibrosing inflammatory disease of the lung parenchyma of unknown cause. It is characterized by slowly increasing dyspnea, diffuse interstitial lung infiltrates, restrictive lung dysfunction, and impaired gas exchange. Ultimately, it is fatal in most patients, and treatment options remain unsatisfactory. The advent of high-resolution computed tomography of the chest and modifications in the histopathologic classification of interstitial pneumonias have reshaped the concept of IPF. Although initially thought to be a relatively specific clinicopathologic entity, it seems likely that IPF as previously defined is a heterogeneous disorder consisting of several clinicopathologic entities with differing histopathologic patterns, clinical course, response to therapy, and prognosis. The most common histologic pattern in cases previously defined as IPF is usual interstitial pneumonia, which is associated with a median survival of less than 3 years. For accurate prognosis and optimal management of patients, the clinician should attempt to be as precise as possible in distinguishing various clinicopathologic entities that have been included under the clinical heading of IPF. In the future, we recommend that the use of the term "idiopathic pulmonary fibrosis" be restricted to patients with usual interstitial pneumonia and that clinicians recognize the fact that other idiopathic interstitial pneumonias do not have the same prognostic effect traditionally ascribed to IPF.

Bronchiolitis obliterans organizing pneumonia in Korea

An analysis of the clinical features in 23 cases of bronchiolitis obliterans organizing pneumonia (BOOP) in Korea is presented. Six were men and 17 were female, with a male-to-female ratio of 1:2.4. Idiopathic BOOP was present in 18 of these patients, connective tissue disease-associated BOOP in five and all of them were females. The most frequent symptoms were dyspnoea and coughing in both groups; and crackles were the most prominent physical findings. Leukocytosis was observed in seven of the idiopathic BOOP group and all in the connective tissue disease-associated BOOP group. In most cases, FVC, FEV 1, diffusing capacity and arterial O2 pressure were reduced. In roentgenographic study, patchy air space consolidation was the major finding and subpleural predominance was observed in the majority of patients in both groups. Migration of lesions were identified in only two patients with idiopathic BOOP. Steroid treatment was effective in all of idiopathic BOOP. In contrast to previous reports, an analysis of the 23 Korean BOOP patients showed several interesting points. First, a female predominance was observed. Second, migration of lesion was rare. Third, it did not show any different prognosis in patients with reticular pattern on roentgenogram compared with patients with patchy air space consolidation on roentgenogram. Whether these differences were due to ethnic or environmental factors is to be determined.

Bronchiolitis obliterans with organizing pneumonia and cold agglutinin disease associated with phenytoin hypersensitivity syndrome

Phenytoin hypersensitivity syndrome (PHS) is a rare delayed hypersensitivity reaction which occurs following exposure to phenytoin sodium. Pulmonary involvement is uncommonly described. Herein is reported the first case of histopathologic bronchiolitis obliterans organizing pneumonia (BOOP) found on open-lung biopsy in a patient with severe PHS. New onset, clinically significant, cold agglutinin disease was also documented. Hemodynamic parameters mimicking sepsis were present in the absence of significant clinical infection. Rapid, dramatic improvement followed high-dose steroid therapy.

Cyclophosphamide in severe steroid-resistant bronchiolitis obliterans organizing pneumonia

A patient receiving carbamazepine and imipramine presented with severe bronchiolitis obliterans organizing pneumonia (BOOP). He developed progressive respiratory failure in spite of high-dose steroid treatment. Cyclophosphamide was given as adjunctive therapy, and a rapid improvement was seen. The authors suggest that an early therapeutic trial of cyclophosphamide should be considered in patients with BOOP who fail to respond to steroids.

Bronchiolitis obliterans in a patient with HIV infection

Bronchiolitis obliterans, with or without organizing pneumonia, represents an uncommon response of the lung to several injuries, that results in characteristic histopathologic changes in the small airways. The present case report describes a patient with HIV infection who developed bronchiolitis obliterans, and reviews the previously reported cases of this condition in HIV-infected patients.

An evaluation of the Alexander Technique for the management of disability in Parkinson's disease--a preliminary study

OBJECTIVE

To test the effect of the Alexander Technique (AT) on the management of disability and feelings of depression in patients with Parkinson's disease (PD).

DESIGN

Subjects completed four self-report questionnaires, one set before the course of lessons and a repeat set when the lessons were ended. The postal questionnaires were mailed directly to the subject's home from the university with a stamped addressed envelope.

SUBJECTS

Seven volunteers, with no previous experience of the Alexander Technique, diagnosed by consultant neurologists to have idiopathic Parkinson's disease.

SETTING

The subjects were contacted by the nearest registered AT teacher and were taught in the individual teacher's practice rooms, in the same way as other pupils.

INTERVENTIONS

Subjects received a median of 12 lessons.

MAIN OUTCOME MEASURES

The self-report measures were the BECK Depression Inventory, activities in daily living, body concept, and social functioning disability questionnaires.

RESULTS

Post-lessons the subjects were significantly (p < 0.05) less depressed. They had a significantly more positive body concept and had significantly less difficulty in performing daily activities, and significantly less difficulty on the fine movement and gross movement subscales of the activities in daily living questionnaire.

CONCLUSIONS

The statistically significant results are consistent with the hypothesis that for PD patients on drug therapy, the Alexander Technique reduces depression and improves the management of disability, but in the absence of a control group and a larger sample, they cannot be said to confirm the hypothesis. The likelihood of the AT being effective in the management of disability for many PD patients, as shown in this study, makes further controlled research desirable.

A case of bronchiolitis obliterans organizing pneumonia associated with adenovirus

A 58-year-old man described a short history of dyspnea and a preceding flu like illness with roentgenographic features of an interstitial lung disease. An open lung biopsy specimen from him showed bronchiolitis obliterans with organizing pneumonia (BOOP). Adenovirus was isolated from a throat swab. There was both clinical and radiographic improvement with supportive care. We herein report a first case of BOOP associated with adenovirus in Korea.

Outbreak of obstructive ventilatory impairment associated with consumption of Sauropus androgynus vegetable

BACKGROUND

Forty four individuals, suffering from temporary insomnia and poor appetite followed by progressive difficulty breathing after four weeks or more ingestion of the Sauropus androgynus or Sabah vegetable, were reported to the National Poison Center of Taiwan by physicians between August 23, 1994 and August 25, 1995.

OBJECTIVE

A telephone questionnaire survey was designed and conducted to collect demographic data, information about use of the vegetable, past medical history and clinical presentation. Laboratory data were obtained from their physicians as available.

RESULTS

Forty one patients, predominantly women, 43 +/- 11 years old, were identified in our survey. They reported a variety of sources and preparation methods for the vegetable. Difficulty breathing, identified in 36 cases, was the clinical hallmark. Twenty people gave a history of dyspnea delayed until 44 +/- 40 days after discontinuing vegetable consumption. Laboratory evidence of obstructive ventilatory impairment (FEV1/FVC 56 +/- 12%, FEV1 31 +/- 6%, PaO2 71 +/- 15%) was observed in 12 cases tested. An open lung biopsy performed in a demonstration case disclosed bronchiolitis obliterans organizing pneumonia.

CONCLUSION

In this case series of 41 victims, we have identified a severe pulmonary effect and hypothesize that it is related to consumption of sauropus androgynus vegetable. Papaverine has been previously identified in this vegetable but is unlikely to be responsible for the full range of toxicity seen.

Epidemic outbreak of interstitial lung disease in aerographics textile workers--the "Ardystil syndrome": a first year follow up

BACKGROUND

The longer term respiratory effects of massive inhalational exposure of textile printing sprayers to Acramin (the "Ardystil syndrome") are not well established.

METHODS

A 12 month follow up of 27 heavily exposed textile sprayers was performed.

RESULTS

Twenty one patients experienced cough, 18 dyspnoea, and 17 nose bleeding at initial exposure, with histological evidence of organising pneumonia in 13 cases, radiological abnormalities detected by computed tomographic scanning in 20 cases, and diminution of diffusion capacity to below 80% of predicted in seven cases. At one year after exposure symptoms persisted in 15 cases, radiological alterations in six, and diffusion capacity was reduced in nine.

CONCLUSIONS

Whilst most of our patients showed improvement at one year, evidence of persistent lung involvement was present in an appreciable minority of exposed cases.

[Causality in occupational health: the Ardystil case]

Establishing causal relationships has been and is today a matter of debate in epidemiology. The observational nature of epidemiological research rends difficult the proving of these relationships. Related to this, different models and causal criteria have been proposed in order to explain health and disease determinants, from pure determinism in Koch postulates, accepting unicausal explanation for diseases, to more realistic multicausal models. In occupational health it is necessary to formulate causal models and criteria to assess causality, and frequently causal assessment in this field has important social, economic and juridical relevance. This paper deal with evaluation of causal relationships in epidemiology and this evaluation is illustrated with a recent example of an occupational health problem in our milieu: the Ardystil case.