Bronchiolar disorders

Structural and functional abnormalities in lungs in patients with achalasia

Dilatation and oesophageal body aperistalsis in achalasia can lead to stasis which in turn can induce repeated microaspiration. It is therefore conceivable that patients with achalasia may also have abnormalities in lungs secondary to repeated episodes of microaspiration. There is a lack of systematic study on involvement of lungs in patients with achalasia. Thirty patients with achalasia underwent pulmonary function tests (spirometry, and carbon mono-oxide diffusion capacity) and high resolution computerized tomography (HRCT) of the chest. The mean age of patients and mean duration of disease were 33.5 +/- 10.9 years and 28.1 +/- 27.3 months respectively. Regurgitation was present in 22 (73.3%) of them. Respiratory symptoms in them were dry cough in 17 (56.6%), and chest pain in 18 (60%). The oesophagus was dilated in 26 (86.6%) and 13 (43.3%) had residue in oesophagus. Sixteen (53.3%) patients had either anatomical changes as seen on HRCT or functional changes as observed on pulmonary function tests. Of those with functional abnormalities, five (16.6%) and one (3.3%) had restrictive and obstructive airways disease respectively. While evidence of tracheo-bronchial compression by dilated oesophagus was present in eight (26.6%), 10 (33.3%) patients had parenchymal lung disease [nodular opacities in five (16.6%), ground glass appearance six (20%), patchy pulmonary fibrosis five (16.6%), air trapping two (6.6%), consolidation and bronchiectasis one (3.3%) each]. There was a significant association between presence of regurgitation and dilatation of oesophagus (P = 0.032). More than half (53.3%) of patients with achalasia have structural and/or functional abnormalities in lungs.

High-resolution CT findings of bronchiolitis obliterans syndrome after hematopoietic stem cell transplantation

PURPOSE

To describe the high-resolution computed tomography (CT) findings occurring in bronchiolitis obliterans syndrome (BOS) after hematopoietic stem cell transplantation (HSCT) and to determine the relationship between pulmonary function tests (PFTs) and air trapping detected on expiratory CT.

MATERIALS AND METHODS

The high-resolution CT scans of 33 patients who underwent HSCT and subsequently developed BOS were evaluated by 2 observers blinded to PFT results. Scans were ranked for degree of air trapping and scored for findings of bronchial wall thickening, bronchiectasis, and centrilobular opacities. Air-trapping rank was correlated with the degree of airflow obstruction as determined by PFTs.

RESULTS

The ranking of air trapping correlated significantly with 1-second forced expiratory volume (P=0.001), 1-second forced expiratory volume/forced vital capacity (P<0.001), residual volume (P<0.001), carbon monoxide diffusion capacity (P=0.023), but not forced vital capacity (P=0.14) or total lung capacity (P=0.07). Bronchial wall thickening occurred in 73.0%, predominantly in lower lobes (P=0.007), but was mild. Bronchiectasis occurred in 42.4% and centrilobular opacities in 39.4%.

CONCLUSIONS

In BOS developing after HSCT, air trapping is the principal finding on CT, and its severity correlates with PFTs. Bronchial wall thickening is common, but almost always mild; bronchiectasis and centrilobular opacities occur in less than half of cases and are also mild.

Hiperplasia de células neuroendócrinas pulmonares difusas com obstrução ao fluxo aéreo

A hiperplasia de células neuroendócrinas pulmonares difusas com obstrução ao fluxo aéreo é uma lesão pulmonar rara. Todos os casos publicados foram diagnosticados por biópsia pulmonar cirúrgica. Apenas três casos relatados apresentavam opacidades intersticiais difusas na TCAR. Nós relatamos três casos adicionais desta entidade. Todos eram mulheres, com obstrução leve ou moderada ao fluxo aéreo. No primeiro caso, uma biópsia transbrônquica, associada com dados de imagem foram considerados suficientes para o diagnóstico. Um padrão em mosaico foi observado nos três casos, mas no terceiro um infiltrado pulmonar difuso foi também observado. Em casos muito raros, o aspecto na TCAR pode simular aquele encontrado em outras doenças pulmonares intersticiais.

[Bronchial involvement in hypersensitivity pneumonitis]

Hypersensitivity pneumonitis is a respiratory disease resulting from the inhalation of antigens to which the exposed subject has been previously sensitized. Hypersensitivity pneumonitis is characterized by a diffuse and predominantly mononuclear cell inflammation of the alveolar regions that involves the small airways in most cases. It explains the presence of mosaic attenuation and expiratory air trapping at HRCT Scan. Chronic bronchitis, an obstructive defect at lung function tests and emphysema as long-term outcome are frequent consequences of this bronchial involvement.

Follicular bronchiolitis: a rare cause of bronchiolitis obliterans syndrome after lung transplantation: a case report

This case report is the first confirmed case of follicular bronchiolitis (FB), a rare bronchiolar disorder characterized by peribronchiolar lymphoid follicles, in a series of over 400 lung transplantations performed in our center. It is to our knowledge, the first publication describing FB after lung transplantation (LTx), presenting as chronic allograft dysfunction or bronchiolitis obliterans syndrome (BOS).

Chemokine-enhanced chemotaxis of lymphangioleiomyomatosis cells with mutations in the tumor suppressor TSC2 gene

Lymphangioleiomyomatosis (LAM) is characterized by cystic lung destruction caused by LAM cells (smooth-muscle-like cells) that have mutations in the tumor suppressor genes tuberous sclerosis complex (TSC) 1 or 2 and have the capacity to metastasize. Since chemokines and their receptors function in chemotaxis of metastatic cells, we hypothesized that LAM cells may be recruited by chemokine(s) in the lung. Quantification of 25 chemokines in bronchoalveolar lavage fluid from LAM patients and healthy volunteers revealed that concentrations of CCL2, CXCL1, and CXCL5 were significantly higher in samples from LAM patients than those from healthy volunteers. In vitro, CCL2 or MCP-1 induced selective migration of cells, showing loss of heterozygosity of TSC2 from a heterogeneous population of cells grown from explanted LAM lungs. Additionally, the frequencies of single-nucleotide polymorphisms in the CCL2 gene promoter region differed significantly in LAM patients and healthy volunteers (p = 0.018), and one polymorphism was associated significantly more frequently with the decline of lung function. The presence (i.e., potential functionality) of chemokine receptors was evaluated using immunohistochemistry in lung sections from 30 LAM patients. Expression of chemokines and these receptors varied among LAM patients and differed from that seen in some cancers (e.g., breast cancer and melanoma cells). These observations are consistent with the notion that chemokines such as CCL2 may serve to determine mobility and specify the site of metastasis of the LAM cell.

Padrões tomográficos das doenças intersticiais pulmonares difusas com correlação clínica e patológica

A tomografia de alta resolução (TCAR) é a técnica de imagem radiológica que reflete mais de perto as alterações da estrutura pulmonar. Os vários achados tomográficos podem ser combinados para formar padrões típicos. Estes, conjuntamente com a distribuição anatômica dos achados, e com os dados clínicos, podem estreitar o diagnóstico das doenças intersticiais pulmonares difusas, e em vários casos sugerir o diagnóstico correto com alto grau de acurácia. Os padrões mais comuns das doenças intersticiais pulmonares difusas na TCAR são o nodular, linear e reticular, lesões císticas, opacidades em vidro fosco e consolidações. Este artigo revisa as correlações entre os padrões tomográficos na TCAR e os achados patológicos e resume as causas mais comuns e os métodos de investigação para se atingir um diagnóstico nas doenças pulmonares crônicas difusas mais comuns.

Obliterative Bronchiolitis

Obliterative bronchiolitis (OB) is a condition characterized by inflammation and fibrosis of the bronchiolar walls resulting in narrowing or obliteration of the bronchiolar lumen. The most common causes are childhood lower respiratory tract infection, hematopoietic stem cell or lung and heart-lung transplantation, and toxic fume inhalation. The most frequent clinical manifestations are progressive dyspnea and dry cough. Pulmonary function tests demonstrate airflow obstruction and air trapping. Radiographic manifestations include reduction of the peripheral vascular markings, increased lung lucency, and overinflation. The chest radiograph, however, is often normal. High-resolution CT is currently the imaging modality of choice in the assessment of patients with suspected or proven OB. The characteristic findings on high-resolution CT consist of areas of decreased attenuation and vascularity (mosaic perfusion pattern) on inspiratory scans and air trapping on expiratory scans. Other CT findings of OB include bronchiectasis and bronchiolectasis, bronchial wall thickening, small centrilobular nodules, and three-in-bud opacities. Recent studies suggest that hyperpolarized ³He-enhanced magnetic resonance imaging may allow earlier recognition of obstructive airway disease and therefore may be useful in the diagnosis and follow-up of patients with OB.

Follicular bronchiolitis in surgical lung biopsies: clinical implications in 12 patients

BACKGROUND

Follicular bronchiolitis is a histopathologic finding that occurs in diverse clinical contexts. The current study was conducted to characterize clinico-radiologic features, and assess outcomes associated with follicular bronchiolitis.

SUBJECTS AND METHODS

Twelve subjects with follicular bronchiolitis on lung biopsy were seen over a 9-year period, between 1996 and 2005. Medical records, biopsy and radiographic findings, and details of outcome at the time of last follow-up were recorded.

RESULTS

The study population included 4 men and 8 women; the median age at diagnosis was 54 years (range, 33-81 years). Four patients had underlying systemic diseases that included: 2 with common variable immunodeficiency, 1 Sjögren's syndrome and 1 undifferentiated connective tissue disease. The diagnosis was obtained by surgical lung biopsy in all cases. Follicular bronchiolitis was the major histologic pattern in 9 patients; organizing pneumonia, nonspecific interstitial pneumonia and usual interstitial pneumonia was seen in 1 patient each with follicular bronchiolitis being an associated secondary histopathologic component. Computed tomographic findings included reticular opacities, small nodules and ground-glass opacities. Clinical course was characterized by relative stability with partial response to immunosuppressive agents. During a median follow-up period of 47 months, only one death occurred--out of 9 patients where the outcome information was available--and was unrelated to lung disease.

CONCLUSIONS

The histologic lesion of follicular bronchiolitis may be seen as the predominant finding or a relatively minor feature in interstitial pneumonias. The clinical course and prognosis for most patients with follicular bronchiolitis is relatively good, and progressive lung disease is uncommon.

Focal Organizing Pneumonia on Surgical Lung Biopsy

BACKGROUND

Organizing pneumonia (OP) is a histologic pattern that is morphologically distinctive but nonspecific and can be seen in diverse clinical settings. Focal OP has been described as a discrete form of OP, but relatively little is known regarding this clinicopathologic entity.

METHODS

We sought to clarify the clinicoradiologic presentation, underlying causes, and outcomes associated with focal OP by retrospectively reviewing 26 consecutive cases diagnosed by surgical lung biopsy over an 8-year period from January 1, 1997, to December 31, 2004.

RESULTS

All patients presented with an unifocal opacity detected on chest radiography (20 patients) or CT scans (6 patients). At the time of presentation, 10 patients (38%) had symptoms, including cough, shortness of breath, or chest pain; 16 patients were asymptomatic. Contrast-enhancement CT scanning or positron emission tomography (PET) scan was performed in 11 patients, and the results were positive in all. Surgical procedures included wedge resection in 21 patients (81%), segmentectomy in 3 patients (11%), and lobectomy in 2 patients (8%). Three case of focal OP (12%) were related to infections, but the remaining cases were cryptogenic. Follow-up over a median interval of 11 months (range, 1 to 71 months) yielded no recurrence of OP.

CONCLUSIONS

The radiologic features of focal OP are often indistinguishable from those of lung cancer, and include positivity on contrast-enhancement CT scan and PET scan. Most cases of focal OP are cryptogenic, and infection is identified in a minority of cases. Surgical resection alone appears to suffice in the management of cryptogenic focal OP.

Bronchiolitis interstitial pneumonitis: a pathologic study of 31 lung biopsies with features intermediate between bronchiolitis obliterans organizing pneumonia and usual interstitial pneumonitis, with clinical correlation

Bronchiolitis combined with interstitial pneumonitis generally has been equated with bronchiolitis obliterans organizing pneumonia (BOOP). We describe our experience with lung biopsies that had both bronchiolar and interstitial diseases. We studied 31 patients who had respiratory difficulty leading to open lung biopsy, which showed a combination of both prominent bronchiolitis and prominent interstitial pneumonitis. We compared these cases clinically and pathologically with 6 other pulmonary diseases, namely, bronchiolitis obliterans, BOOP, nonspecific interstitial pneumonitis, usual interstitial pneumonitis, airway-centered interstitial fibrosis, and idiopathic bronchiolocentric interstitial pneumonia, and with 10 cases of cystic fibrosis, an unrelated disease with both bronchiolar and interstitial pathology. The commonality of our cases was a combination of bronchiolitis and interstitial inflammation and fibrosis but little or no intra-alveolar organizing pneumonia. Bronchiolitis obliterans with organizing pneumonia involved less area than the interstitial pneumonitis in each case. All 19 patients for whom we had follow-up received corticosteroids for their pulmonary diseases. Seven patients had improvement in symptoms and pulmonary function test results and radiographic findings, 5 patients experienced subjective improvement with unchanged results of pulmonary function tests or chest x-ray, 1 patient's condition was unchanged, 6 patients' disease worsened, and 4 of these 6 died. The natural history of these cases, which we have designated bronchiolitis interstitial pneumonitis, seems more sanguine than usual interstitial pneumonitis and worse than BOOP at least in the short term. On the one hand, response to corticosteroids was not as frequent as generally accepted for BOOP. On the other hand, disease did not progress in most patients on corticosteroids.

Diagnosis of interstitial lung diseases

Interstitial lung diseases (ILDs), a broad heterogeneous group of parenchymal lung disorders, can be classified into those with known and unknown causes. The definitions and diagnostic criteria for several major forms of ILDs have been revised in recent years. Although well over 100 distinct entities of ILDs are recognized, a limited number of disorders, including idiopathic pulmonary fibrosis, sarcoidosis, and connective tissue disease-related ILDs, account for most ILDs encountered clinically. In evaluating patients with suspected ILD, the clinician should confirm the presence of the disease and then try to determine its underlying cause or recognized clinicopathologic syndrome. Clues from the medical history along with the clinical context and radiologic findings provide the initial basis for prioritizing diagnostic possibilities for a patient with ILD. High-resolution computed tomography of the chest has become an invaluable tool in the diagnostic process. A confident diagnosis can sometimes be made on the basis of high-resolution computed tomography and clinical context. Serologic testing can be helpful in selected cases. Histopathologic findings procured through bronchoscopic or surgical lung biopsy are often needed in deriving a specific diagnosis. An accurate prognosis and optimal treatment strategy for patients with ILDs depend on an accurate diagnosis, one guided by recent advances in our understanding of the causes and pathogenetic mechanisms of ILDs.

Clinical features of allogeneic hematopoietic stem cell transplantation-associated organizing pneumonia

We describe the clinical courses and outcomes of allogeneic hematopoietic stem cell transplantation-associated organizing pneumonia (HOP) observed in our institution over the past 20 years. Charts and chest radiographs of 603 allogeneic transplant recipients were retrospectively reviewed for HOP. In total, 12 cases of HOP were identified (2.0%) at a median interval of 148 days after transplantation (range, 53-475 days), presenting with low-grade fever, nonproductive cough and dyspnea at onset. Initial antibiotic treatment did not ameliorate symptoms, but most patients responded well to 0.5-1 mg/kg of prednisolone. HOP flare-up occurred after discontinuing treatment or while tapering doses in 9 of 12 patients, but responded to re-treatment with the initial dose of steroid. Although three patients died, no deaths were attributable to pulmonary failure. The remaining nine patients displayed no relapse of primary disease and 5-year survival rate was 74.1%. Clinical features of the 12 patients were similar in that all underwent irradiation-containing conditioning and most had a prior history of acute graft-versus-host disease (GVHD) and cytomegalovirus (CMV) infection. Furthermore, eight patients had active chronic GVHD at onset of HOP. These findings suggest that factors such as irradiation-containing regimens, previous CMV infection and allogeneic immune reaction may contribute to HOP occurrence.

Causes and presenting features in 85 consecutive patients with hypersensitivity pneumonitis

OBJECTIVE

To assess the current spectrum of causes and clinical features associated with hypersensitivity pneumonitis (HP).

PATIENTS AND METHODS

We studied consecutive patients with HP diagnosed at the Mayo Clinic in Rochester, Minn, from January 1, 1997, through December 31, 2002. Diagnostic criteria for HP included the following: (1) presence of respiratory symptoms, (2) radiologic evidence of diffuse lung disease, (3) known exposure or a positive serologic test result to an inciting antigen, and (4) no other identifiable cause for the lung disease. If there was no identifiable inciting antigen, 1 of the following 2 criteria was required: (1) lung biopsy specimen that demonstrated features of HP or (2) bronchoalveolar lavage lymphocytosis and high-resolution computed tomographic evidence of ground-glass opacities or centrilobular nodules bilaterally.

RESULTS

The mean +/- SD age of the 85 study patients was 53 +/- 14 years; 53 patients (62%) were women. Only 2 patients (2%) were current smokers. Chronic (> or = 4 months) respiratory symptoms were present in 66 patients (78%). Histopathologic confirmation was obtained in 64 patients (75%). The cause was identified in 64 patients (75%), and the most common causes were avian antigens (34%) and Mycobacterium avium complex in hot tub water (21%). Farmer's lung disease accounted for 11% of cases, and an additional 9% were related to household mold exposure. The inciting antigen was not identifiable in 25% of patients.

CONCLUSION

Most patients with HP seen at this tertiary care referral center in the Midwest region of the United States had chronic HP, and the most common causes were exposure to birds and exposure to hot tubs.

Bronchoalveolar cellularity and interleukin-8 levels in measles bronchiolitis obliterans

BACKGROUND

Measles virus infection may progress to a chronic obstructive process including bronchiolitis obliterans (BO). This study investigates pulmonary cellular profiles and interleukin (IL)-8 levels in patients with BO following the measles.

METHODS

BAL fluid was obtained from 12 children with BO who had a history of measles pneumonia during an outbreak in 2000 and 2001. BAL cell counts and differentials were compared to control patients as well as BAL IL-8 levels, which were measured by enzyme-linked immunosorbent assay. Immunohistochemical staining of BAL cells and three open-lung biopsy specimens were also analyzed for T-cell surface markers CD3, CD4, and CD8.

RESULTS

BAL cellular profiles were characterized by a significantly increased percentage of neutrophils in the measles BO group (median, 16.0%) compared to the control group (2.3%) [p < 0.01]. BAL IL-8 levels were also markedly increased in the measles BO group (mean +/- SD, 418.6 +/- 286.0 pg/mL) compared to the control group (92.8 +/- 126.7 pg/mL) [p < 0.01]. BAL IL-8 levels correlated significantly with neutrophil percentages in both the measles BO group (r = 0.86, p = 0.000) and the control group (r = 0.79, p = 0.007). The lymphocyte subsets were characterized by a significantly increased number of CD8+ cells, resulting in a decreased CD4/CD8 ratio in the BAL and the biopsy specimens.

CONCLUSION

These results suggest that pulmonary neutrophils and IL-8, along with CD8+ T lymphocytes may play an important role in the pathogenesis of BO after measles virus infection.

63-jährige Türkin mit rezidivierenden Pneumonien

The differential diagnosis of a sinubronchial syndrome includes cystic fibrosis, allergic bronchopulmonic aspergillosis, Kartagener's syndrome, hypogammaglobulinemia and bronchioli-associated processes. The latter include cryptogenic organising pneumonia, constrictive bronchiolitis obliterans as well as the respiratory bronchiolitis. Our case presented a persistent interstitial shadow in the x-rax of the thorax and a relevant, mixed ventilation disturbance in lung function. A surgically performed lung biopsy finally allowed the diagnosis of diffuse panbronchiolitis, which is seldom found in central Europe. This disease is of unknown etiology and responds to long-term macrolide therapy.

Significance of multiple carcinoid tumors and tumorlets in surgical lung specimens: analysis of 28 patients

BACKGROUND

The clinical significance of multiple carcinoid tumorlets in surgical lung specimens has not been systematically analyzed. We reviewed our experience to determine the range of clinical circumstances associated with this finding.

METHODS

We reviewed clinical records, available imaging, and pathology materials from patients evaluated at Mayo Clinic Rochester (from 1987 to 2000) with two or more carcinoid tumors or tumorlets in lung specimens.

RESULTS

Twenty-eight of 294 patients with a diagnosis of carcinoid tumor or tumorlet had two or more lesions. Twenty-six patients (93%) were women; mean age was 65 years. Patients were categorized into three groups: multiple nodules (n = 17), solitary lung nodules on preoperative imaging (n = 7), and airflow limitation (n = 4). Approximately half of patients with multiple nodules had respiratory complaints; two patients had Cushing syndrome. Ten patients (58.8%) were suspected of having pulmonary metastases, including 7 patients with previously diagnosed malignancies. Intrathoracic lymph node metastases were present in three patients, none of whom had recurrent disease. One patient had a carcinoid tumor resected 8 years later. Extrathoracic metastases developed in another patient 3 years after presentation, and the patient was alive with disease 2 years later. Only one patient with airflow limitation had a syndrome resembling diffuse idiopathic pulmonary neuroendocrine cell hyperplasia.

CONCLUSIONS

Our series represents the largest compilation of multiple carcinoid tumors or tumorlets. Our analysis reveals that multiple carcinoid tumors or tumorlets occur most commonly in patients with multiple nodules resembling metastatic disease. Significant airflow limitation is rare. Long-term survival is excellent, although patients have persistent disease.

Organizing pneumonia in patients with hematologic malignancies: A steroid-responsive lesion

BACKGROUND

Organizing pneumonia (OP) is a distinct histopathologic lesion that occurs in a variety of clinical contexts. There have been occasional reports of OP occurring in patients with hematologic malignancies.

STUDY OBJECTIVES

To examine the association of OP with hematologic malignancies and to assess the clinical course of affected patients.

DESIGN

A retrospective review of our institutional experience of unexplained OP developing in patients with hematologic malignancies.

SETTING

Tertiary care, referral medical center.

PATIENTS

We identified 6 patients with a verified histopathologic diagnosis of OP and antecedent or concomitant diagnosis of a hematologic malignancy from the Mayo Clinic database (1995-2003). Clinical, radiologic, and outcome data were abstracted from records.

RESULTS

Underlying hematologic disorders included lymphoma (2), acute leukemia (2), cutaneous T-cell lymphoma (1), and myelodysplastic syndrome (1). OP was diagnosed by surgical lung biopsy in 4 and bronchoscopic biopsy in 2. Four of the 6 patients had previously been exposed to chemotherapeutic agents, two had not. Three of the 6 patients had bone marrow transplantation prior to development of OP. Five patients were treated with prednisone and all experienced symptomatic improvement with documented radiologic resolution in 4. One patient experienced symptomatic and radiologic resolution with observation alone. Three patients ultimately died from complications of their underlying hematologic disorder and 1 patient died of unknown causes. Two patients were alive without respiratory complaints more than 1 year after lung biopsy.

CONCLUSIONS

OP occurs in patients with underlying hematologic malignancies who may or may not have been treated with chemotherapy and responds favorably to corticosteroid therapy.

Thalidomide-induced Organizing Pneumonia

Twenty medications are associated with drug-induced organizing pneumonia; however, thalidomide is not listed as a potential causative agent. Thalidomide (Thalomid, Celgene Corp., Summit, NJ), an angiogenesis inhibitor and immunomodulator that reduces tumor necrosis factor-alpha, is used for the treatment of multiple myeloma. We report a case of organizing pneumonia in a 58-year-old male with multiple myeloma treated with dexamethasone and thalidomide.

Classification and approach to bronchiolar diseases

PURPOSE OF REVIEW

Bronchiolar abnormalities are relatively common and occur in a variety of clinical contexts. There have been an increasing number of terms, some of which are redundant, used in referring to various forms of bronchiolar disorders. The purpose of this review is to provide an updated classification scheme to facilitate the clinical approach to patients with suspected bronchiolar disease.

RECENT FINDINGS

The spectrum of bronchiolar disorders is broader and more heterogeneous than previously recognized. In deciphering the potential significance of bronchiolar abnormalities, it is useful to distinguish those disorders in which the bronchiolar involvement is the dominant pathologic process, that is, primary bronchiolar disorders, from parenchymal or large airway diseases in which the bronchioles may become secondarily involved. Primary bronchiolar disorders include respiratory bronchiolitis, acute bronchiolitis, constrictive bronchiolitis, follicular bronchiolitis, diffuse panbronchiolitis, mineral dust airway disease, and a few other variants. Interstitial lung diseases with a prominent bronchiolar involvement include smoking-related interstitial lung diseases, cryptogenic organizing pneumonia, and hypersensitivity pneumonitis. Bronchiolitis can also be seen in large airway diseases such as chronic bronchitis, bronchiectasis, and asthma.

SUMMARY

In the clinical approach to a patient with bronchiolar disease, primary bronchiolar disorders should be distinguished from predominantly parenchymal or large airway processes with bronchiolar involvement. The number of patterns of bronchiolar response to injury is limited and these patterns are generally non-specific in regard to cause. Appropriate diagnosis and management of patients with bronchiolar disorders depend on judicious correlation of clinical, physiologic, and morphologic manifestations.

Modulatory role for retinoid-related orphan receptor alpha in allergen-induced lung inflammation

RATIONALE

Nuclear receptors play a critical role in the regulation of inflammation, thus representing attractive targets for the treatment of asthma.

OBJECTIVE

In this study, we assess the potential regulatory function of retinoid-related orphan receptor alpha (RORalpha) in the adaptive immune response using ovalbumin (OVA)-induced airway inflammation as a model.

METHODS

Allergen-induced inflammation was compared between wild-type (WT) and staggerer (RORalpha(sg/sg)) mice, a natural mutant strain that is deficient in RORalpha expression.

MEASUREMENTS AND MAIN RESULTS

Despite robust increases in OVA-specific IgE, RORalpha(sg/sg) mice developed significantly less pulmonary inflammation, mucous cell hyperplasia, and eosinophilia compared with similarly treated WT animals. Induction of Th2 cytokines, including interleukin (IL)-4, IL-5, and IL-13, was also significantly less in RORalpha(sg/sg) mice. Microarray analysis using lung RNA showed increased expression of many genes, previously implicated in inflammation, in OVA-treated WT mice. These include mucin Muc5b, the chloride channel calcium-activated 3 (Clca3), macrophage inflammatory protein (MIP) 1alpha and 1beta, eotaxin-2, serum amyloid A3 (Saa3), and insulin-like growth factor 1 (Igf1). These genes were induced to a greater extent in OVA-treated WT mice relative to RORalpha(sg/sg) mice.

CONCLUSIONS

Our study demonstrates that mice deficient in RORalpha exhibit an attenuated allergic inflammatory response, indicating that RORalpha plays a critical role in the development of Th2-driven allergic lung inflammation in mice, and suggests that this nuclear receptor should be further evaluated as a potential asthma target.

Macrolide antibiotics and bronchiolitis obliterans following lung transplantation

The anti-inflammatory effects of macrolide antibiotics are of emerging importance. Over the past 20 years, chronic inflammatory respiratory conditions, including diffuse panbronchiolitis, cystic fibrosis and asthma have benefited from long-term low-dose macrolide therapy. Obliterative bronchiolitis, a form of chronic allograft dysfunction in lung transplant recipients, has been reported to be a condition in which macrolide therapy may be indicated. A number of recent cohort studies have been encouraging. Disease progression was delayed with macrolide antibiotic therapy as patients showed a sustained improvement in pulmonary function tests. Up to now, obliterative bronchiolitis has been resistant to most forms of proposed treatment. This review aims to highlight the etiology of obliterative bronchiolitis, the mechanisms of immunomodulation associated with macrolide therapy and how macrolide therapy may be effective by way of these possible mechanisms.

Obliterative bronchiolitis in a patient with myelodysplastic syndrome before bone marrow transplantation

Obliterative bronchiolitis (OB) is known to result from many causes, such as post-bone marrow transplantation, autoimmune and infectious causes, and from drugs. We report a 16-year-old female patient who was diagnosed with myelodysplastic syndrome (MDS) and referred for pulmonary evaluation prior to bone marrow transplantation (BMT). Her chief complaints were progressive cough and dysponea. Her radiological and pulmonary function tests were highly suggestive of advanced OB, which was confirmed by a lung biopsy. She eventually died despite steroid therapy. The possible aetiology of OB in this patient is discussed, but, to our knowledge, this is the first case report of OB associated with MDS.

Pictorial Essay: Multinodular Disease

The evaluation of patients presenting with multinodular pulmonary disease provides an important clinical challenge for physicians. The differential diagnosis includes an extensive list of benign and malignant processes making the management of these cases frequently problematic. With the introduction of high-resolution CT (HRCT) scanning, the ability to assess various patterns of diffuse multinodular disease has evolved into an essential part of the diagnostic process. The purpose of this article is to develop an approach to the diagnosis of multinodular parenchymal disease using HRCT scan pattern recognition as a point of departure.

Diffuse bronchiolar disease due to chronic occult aspiration

OBJECTIVE

To describe clinical, radiological, and histopathologic features of diffuse bronchiolar disease due to chronic occult aspiration.

PATIENTS AND METHODS

We identified 4 patients encountered from July 2001 to January 2004 who had persistent respiratory symptoms and lung Infiltrates and who were eventually diagnosed by surgical lung biopsy as having diffuse bronchiolar disease due to chronic occult aspiration. Medical records, radiological studies, and histopathologic specimens were reviewed to assess their clinicoradiologic presentation and diagnostic features.

RESULTS

The mean age of these 4 patients was 50 years (age range, 41-59 years), and 2 were women. All presented with persistent dyspnea, cough, and lung infiltrates. Three had a history of gastroesophageal reflux, but only 1 had active symptoms. Chest radiography showed interstitial infiltrates, whereas the predominant finding on computed tomography was numerous centrilobular nodules in all patients. Bronchoscopic lung biopsies had been performed in all patients, and the results were nondiagnostic. Surgical lung biopsy specimens revealed diagnostic features that consisted of bronchiolocentric organizing pneumonia with giant cells that contained material consistent with food in all 4 patients.

CONCLUSION

Diffuse bronchiolar disease likely represents an underrecognized form of aspiration-related lung disease and may occur in relatively young Individuals without symptoms suggestive of recurrent aspiration. Radiological features associated with this disorder are distinctively different from those seen in aspiration pneumonia.

Chronic Cough Due to Nonbronchiectatic Suppurative Airway Disease (Bronchiolitis)

OBJECTIVES

To review the role of nonbronchiectatic suppurative airway disease (bronchiolitis) in the spectrum of causes of cough and its management.

DESIGN/METHODOLOGY

A MEDLINE search (through May 2004) for studies published in the English language since 1980 on human subjects using the medical subject heading terms "cough," "causes of cough," "etiology of cough," "interstitial lung disease," "bronchiolitis," "bronchiolitis obliterans," "diffuse panbronchiolitis," and "inflammatory bowel disease" was performed. Case series and prospective descriptive clinical trials were selected for review. Any references from these studies that were pertinent to the topic were also obtained.

RESULTS/CONCLUSIONS

In patients with cough in whom other more common causes of cough have been excluded, incomplete or irreversible airflow limitation, small airways disease seen on high-resolution CT scan, or purulent secretions seen on bronchoscopy, should suggest nonbronchiectatic suppurative airways disease (bronchiolitis) as a potential primary cause. Successful management depends on the identification of the specific underlying disorder.

Nitric Acid-Induced Bronchiolitis in Rats Mimics Childhood Bronchiolitis obliterans

BACKGROUND

Childhood bronchiolitis obliterans (CBO) is an infrequent but severe disease, characterized by persistent obstructive respiratory symptoms after an acute episode of bronchiolitis. Its etiology is mostly postviral, especially in developing countries. Pathologically, CBO is characterized as constrictive-type BO. The pathogenesis of this disease is poorly understood and there is no specific treatment. Animal models could help to better understand the sequence of events culminating in bronchiolar obliteration and serve as basis for experimental therapeutic research.

OBJECTIVES

In this study, we adapted the nitric acid (NA) technique to develop a suitable model to study CBO in rats.

METHODS

We have intratracheally instilled 0.5% NA or saline and studied the histological lesions on days 2, 7, 14 and 30. NA-instilled animals developed a sequence of bronchiolar lesions that included necrotizing bronchiolitis, proliferative (PROL) bronchiolar lesions and constrictive (CONS) bronchiolar lesions with bronchiectasis, mucostasis and macrophagic accumulation.

RESULTS

The frequency of PROL lesions decreased and that of the CONS lesions increased, with a statistically significant difference at the sacrifice days, except for day 7 (PROL vs. CONS lesions day 2: p = 0.001; PROL vs. CONS lesions day 7: p = 0.38; PROL vs. CONS lesions day 14: p < 0.001; PROL vs. CONS lesions day 30: p < 0.001).

CONCLUSIONS

We conclude that this model presents histological similarities with the histological picture of CBO, being suitable for further developmental and therapeutic experimental research in this field.

Sub-chronic inhalation of high concentrations of manganese sulfate induces lower airway pathology in rhesus monkeys

BACKGROUND

Neurotoxicity and pulmonary dysfunction are well-recognized problems associated with prolonged human exposure to high concentrations of airborne manganese. Surprisingly, histological characterization of pulmonary responses induced by manganese remains incomplete. The primary objective of this study was to characterize histologic changes in the monkey respiratory tract following manganese inhalation.

METHODS

Subchronic (6 hr/day, 5 days/week) inhalation exposure of young male rhesus monkeys to manganese sulfate was performed. One cohort of monkeys (n = 4-6 animals/exposure concentration) was exposed to air or manganese sulfate at 0.06, 0.3, or 1.5 mg Mn/m3 for 65 exposure days. Another eight monkeys were exposed to manganese sulfate at 1.5 mg Mn/m3 for 65 exposure days and held for 45 or 90 days before evaluation. A second cohort (n = 4 monkeys per time point) was exposed to manganese sulfate at 1.5 mg Mn/m3 and evaluated after 15 or 33 exposure days. Evaluations included measurement of lung manganese concentrations and evaluation of respiratory histologic changes. Tissue manganese concentrations were compared for the exposure and control groups by tests for homogeneity of variance, analysis of variance, followed by Dunnett's multiple comparison. Histopathological findings were evaluated using a Pearson's Chi-Square test.

RESULTS

Animals exposed to manganese sulfate at > or = 0.3 mg Mn/m3 for 65 days had increased lung manganese concentrations. Exposure to manganese sulfate at 1.5 mg Mn/m3 for > or = 15 exposure days resulted in increased lung manganese concentrations, mild subacute bronchiolitis, alveolar duct inflammation, and proliferation of bronchus-associated lymphoid tissue. Bronchiolitis and alveolar duct inflammatory changes were absent 45 days post-exposure, suggesting that these lesions are reversible upon cessation of subchronic high-dose manganese exposure.

CONCLUSION

High-dose subchronic manganese sulfate inhalation is associated with increased lung manganese concentrations and small airway inflammatory changes in the absence of observable clinical signs. Subchronic exposure to manganese sulfate at exposure concentrations (< or = 0.3 mg Mn/m3) similar to the current 8-hr occupational threshold limit value established for inhaled manganese was not associated with pulmonary pathology.

Comparative clinicopathology of obliterative bronchiolitis and diffuse panbronchiolitis

BACKGROUND

The progressive airway obliteration caused by obliterative bronchiolitis (OB) has been widely noted in the world. In contrast, the obstructive respiratory disorder caused by diffuse panbronchiolitis (DPB) has been reported mainly from Japan. Therefore, there might be a considerable overlap between OB and DPB in Japan.

OBJECTIVES AND METHODS

To clarify the clinicopathological similarities as well as the differences between OB and DPB, 15 patients with OB and 6 patients with DPB were evaluated clinicopathologically.

RESULTS

The underlying disorders in OB were graft-versus-host disease (GVHD) in 7, rheumatoid arthritis in 3, Kartagener's syndrome in 2, and polymyositis/dermatomyositis, non-tuberculous mycobacterial disease and mycoplasmal pneumonia in one each. The lung pathology demonstrated that the primary obstructive lesions were in the membranous bronchioli in OB. In contrast, they were confined to the respiratory bronchioli in DPB. In addition, OB was classified into two major morphologic types, namely, constrictive and cellular. Clinical manifestations included cough and/or dyspnea in 13 with OB and in 6 with DPB, chronic parasinusitis in 3 with cellular OB and in 6 with DPB. The pulmonary function tests revealed obstructive impairments in all patients with OB and DPB. The chest CT images showed small centrilobular nodules in 64% of those with OB and in all with DPB. The prognosis of constrictive OB was worse than that of cellular OB and DPB.

CONCLUSIONS

This study demonstrated that histopathologically marked differences existed between OB and DPB, although striking similarities in clinical manifestations were also noted in both diseases.

Successful treatment of bronchiolitis obliterans in a bone marrow transplant patient with tumor necrosis factor-alpha blockade

Bronchiolitis obliterans (BO) in children is a rare, inflammatory/fibrosing process involving the small airways that often results in progressive, irreversible obstructive pulmonary disease. Because treatment has focused mainly on supportive care and generally unsuccessful immunosuppression, children with BO experience significant morbidity and mortality. We report a case of biopsy-proven BO after bone marrow transplantation in a child who, after failed corticosteroid therapy, was treated with infliximab, a monoclonal antibody with binding specificity for human tumor necrosis factor-alpha. With initiation of treatment, her pulmonary symptoms and radiographic and spirometric evidence of BO resolved. Nine months later, she remains asymptomatic and shows no evidence of pulmonary decompensation. This case illustrates a successful treatment of BO with selective tumor necrosis factor-alpha blockade.

[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 respiratory system in connective tissue disorders

The connective tissue disorders (also called collagen vascular diseases) represent an heterogeneous group of immunologically mediated inflammatory disorders with a large variety of affected organs besides the lungs. The respiratory system may be involved in all its components: airways, vessels, parenchyma, pleura, respiratory muscles, etc. The frequency, clinical presentation, prognosis and response to therapy vary, depending on the pattern of involvement as well as on the underlying connective tissue disorders. The subject of this review is to describe the most frequent type of lung disorders observed in patients with connective tissue disease (CTD). We will focus on the most frequent CTD: systemic lupus erythematosus, rheumatoid arthritis, scleroderma, Sjogren's syndrome, dermatopolymyositis and mixed CTD.