Importance of diffuse aspiration bronchiolitis caused by chronic occult aspiration in the elderly

Imaging of Small Airways Disease

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

Diffuse Aspiration Bronchiolitis With Neuromyelitis Optica Spectrum Disorder

Diffuse aspiration bronchiolitis (DAB) is a chronic inflammatory response of the bronchioles caused by repeated aspiration of foreign bodies. It is common among older individuals with dysphagia associated with neurological diseases or dementia. Here, we present the case of a woman in her 40s who was presumed to have developed DAB due to neuromyelitis optica spectrum disorder (NMOSD). There have been no reports of DAB due to NMOSD. The absence of obvious episodes of aspiration and the fact that pneumonia was the predominant symptom delayed the diagnosis despite the appearance of specific neurological abnormalities. DAB caused by neurological diseases of the brainstem should be considered in younger patients with diffuse centrilobular opacities, even if dysphagia is not obvious.

High Level of Blood Eosinophils and Localization of Bronchiectasis in Patients with Severe Asthma: A Pilot Study

Background. Severe asthma and bronchiectasis are heterogeneous diseases that frequently coexist. The location of bronchiectasis is generally determined by specific underlying pathophysiological mechanisms. The aim of this study was to determine whether in a population suffering from both severe asthma and bronchiectasis there was a correlation between eosinophilic inflammation and localization of bronchiectasis. Methods. We enrolled 41 patients with coexisting bronchiectasis from eight different severe asthma center outpatient clinics and collected the following data: baseline characteristics, Asthma Control Test, Asthma Control Questionnaire, IgE level, blood count, high-resolution computed tomography and bronchiectasis-related parameters, skin prick test, FeNO50 and flow-volume spirometry. The study was retrospectively registered. Results. The presence of eosinophils > 1000 cells/μL was related to distribution of lower pulmonary bronchiectasis (9.1% upper lobes vs. 53.3% lower lobes, p = 0.014). Indeed, the presence of eosinophilic counts > 1000 increased the probability of lower localization of bronchiectasis compared to upper lobes (ODD 0.088 (0.010−0.772), p = 0.028). Conclusions. An increase in blood eosinophils > 1000 cells/μL seems to be associated with lower preferential localization of bronchiectasis with sparing of the upper lung lobes. This could represent a new potential radiological phenotype that could have a dedicated therapeutic strategy in the future.

Surgical Emergencies in the ICU

Surgical emergencies are common in the critical care setting and require prompt diagnosis and management. Here, we discuss some of the surgical emergencies involving the gastrointestinal, hepatobiliary, and genitourinary sites. In addition, foreign body aspiration and necrotizing soft-tissue infections have been elaborated. Clinicians should be aware of the risk factors, keys examination findings, diagnostic modalities, and medical as well as surgical treatment options for these potentially fatal illnesses.

Broncoaspiración en el anciano: reflejo de la disfagia como síndrome geriátrico

Mujer de 86 años con enfermedad de Alzheimer, ingresa al hospital por síntomas respiratorios; estudio de imagen con lesión redondeada obstructiva a nivel del bronquio intermediario atribuido a broncoaspiración de cuerpo extraño (arveja). Se exhibe la asociación entre un síndrome geriátrico y una complicación respiratoria prevenible con rehabilitación y educación.

A Case of Chronic Aspiration Bronchiolitis

Chronic aspiration bronchiolitis or diffuse aspiration bronchiolitis is a rare disease characterized by chronic inflammation of the bronchioles due to recurrent aspiration of foreign material. To date, there are limited data on chronic aspiration bronchiolitis because it is often present subclinically or remains undiscovered until autopsy. Additionally, time to diagnosis is often prolonged and includes invasive workup prior to definitive diagnosis. Here, we present a case of lung disease attributed to chronic aspiration after a thorough workup resulted in histopathology consistent with a primary diagnosis of aspiration bronchiolitis. Radiographic and pathologic specimens also demonstrated features of usual interstitial pneumonia adding to the complexity of pathology that can be seen with aspiration diseases.

The current definition, epidemiology, animal models and a novel therapeutic strategy for aspiration pneumonia

In the 21st century, aspiration pneumonia (ASP) is very common in older patients, and has a high mortality rate. ASP is diagnosed following confirmation of inflammatory findings in the lungs and overt aspiration or the existence of dysphagia. It is dominant in hospitalized community-acquired pneumonia (CAP), nursing and healthcare-associated pneumonia (NHCAP), and hospital-acquired pneumonia (HAP). The incidence of ASP is increasing every year. The human and experimental animal data revealed that micro-aspiration due to dysphagia during the night is the central mechanism of ASP. Therefore, the precise assessment of swallowing function is the key to diagnose ASP. From a therapeutic point of view, an appropriate administration of antibiotics, as well as a comprehensive approach for dysphagia plays a pivotal role in the prognosis and recovery from ASP. The non-pharmacologic approach, including swallowing rehabilitation and oral care, and a pharmacologic approach including ACE inhibitors and bronchodilators, are essential modalities for treatment and prevention of ASP. The clinical data of NHCAP provides us with a promising treatment strategy for ASP.

A case of diffuse aspiration bronchiolitis due to oesophageal stenosis after radiation therapy

A 66-year-old woman was hospitalized for recurrent pneumonia twice in 1 year. After treatment for pneumonia, chronic coughing, sputum and low-grade fever continued, so she was referred and admitted to our hospital for investigation. Chest computed tomography revealed a lung infiltrative shadow and diffuse centrilobular micronodules. Histological findings from transbronchial lung biopsy showed chronic inflammation and giant cells in the bronchiole. These findings were compatible with diffuse aspiration bronchiolitis (DAB), which is characterized by chronic inflammation of the bronchioles caused by recurrent aspiration of foreign bodies. Oesophagogastroduodenoscopy revealed stenosis of the oesophageal entrance, which was thought to be caused by radiation therapy for hypopharyngeal cancer 20 years before. Antibiotic treatment ameliorated the centrilobular nodule shadow. After discharge, there was no recurrence. This is the first case report of DAB resulting from oesophageal stenosis associated with hypopharyngeal cancer and will serve as an educational case.

Overview and Challenges of Bronchiolar Disorders

Bronchiolar abnormalities are common and can occur in conditions that affect either the large airways or the more distal parenchyma. In this review, we focus on the diagnosis and management of primary bronchiolar disorders, or conditions in which bronchiolitis is the predominant pathologic process, including constrictive bronchiolitis, follicular bronchiolitis, acute bronchiolitis, respiratory bronchiolitis, and diffuse panbronchiolitis. Due to the nature of abnormalities in the small airway, clinical and physiological changes in bronchiolitis can be subtle, making diagnosis challenging. Primary bronchiolar disorders frequently present with progressive dyspnea and cough that can be out of proportion to imaging and physiologic studies. Pulmonary function tests may be normal, impaired in an obstructive, restrictive, or mixed pattern, or have an isolated decrease in diffusion capacity. High-resolution computed tomography scan is an important diagnostic tool that may demonstrate one or more of the following three patterns: 1) solid centrilobular nodules, often with linear branching opacities (i.e., "tree-in-bud" pattern); 2) ill-defined ground glass centrilobular nodules; and 3) mosaic attenuation on inspiratory images that is accentuated on expiratory images, consistent with geographic air trapping. Bronchiolitis is often missed on standard transbronchial lung biopsies, as the areas of small airway involvement can be patchy. Fortunately, many patients can be diagnosed with a combination of clinical suspicion, inspiratory and expiratory high-resolution computed tomography scans, and pulmonary function testing. Joint consultation of clinicians with both radiologists and pathologists (in cases where histopathology is pursued) is critical to appropriately assess the clinical-radiographic-pathologic context in each individual patient.

Reflux-Aspiration in Chronic Lung Disease

Microaspiration, or silent aspiration, is commonly suspected in patients with refractory respiratory symptoms, including unexplained chronic cough, asthma, chronic obstructive pulmonary disease, bronchiolitis, bronchiectasis, and idiopathic pulmonary fibrosis. This suspicion is driven by the high prevalence of gastroesophageal reflux in these otherwise disparate disorders. Frequently, patients receive aggressive treatment for gastroesophageal reflux disease as a means of treating their underlying respiratory conditions, even in the absence of overt symptoms of reflux. However, clinical trials have not demonstrated a clear impact on outcomes with this strategy, and in some instances there may be potential for harm. Mechanistic studies have increasingly used gastric biomarkers obtained directly from the airways to confirm the association between reflux and respiratory disease, but results are limited by methodologic flaws and correlation. The best evidence of aspiration directly causing respiratory disorders is the histopathologic detection of foreign bodies. For most of the other chronic respiratory disorders, microaspiration may be uncommon or a secondary aggravating factor, as in patients with acute exacerbations of chronic obstructive pulmonary disease or idiopathic pulmonary fibrosis. In some cases, microaspiration is probably not a significant factor at all, such as in unexplained chronic cough. It is important to distinguish between conditions in which aspiration is primarily or directly causal and conditions in which aspiration may be indirectly aggravating, to help identify whether interventions targeting reflux and aspiration precautions should be recommended to patients. Our clinical review examines some of the evidence supporting reflux-aspiration as a mechanism for several chronic respiratory disorders and offers some management considerations when reflux-aspiration is suspected.

Investigation of high-resolution computed tomographic (HRCT) outcomes associated with chronic pulmonary microaspiration (CPM) in Tehran and Zahedan, Iran

Background

In patients with chronic pulmonary microaspiration (CPM) the recognition of high-resolution computed tomographic (HRCT) findings and their pattern is important.

Objective

To investigate the HRCT detections in patients with CPM.

Materials and Methods

This descriptive study enrolled 100 consecutive patients with CPM underwent HRCT of the lungs between 2017 and 2018 in Tehran and Zahedan Hospitals and private centers. The required variables were recorded for each patient with a questionnaire. Subsequently, HRCT was performed and abnormalities were then reported by two radiologists.

Results

Most of patients exhibited bronchial thickening in 33.6% of cases, followed by ground-glass opacity (12.4%), emphysema (11.1%), and bronchiectasis (8.5%). In addition, the most common HRCT findings were found in left lower lobe (LLL) (37.1%), followed by right lower lobe (RLL) (35.9 %), right upper lobe (RUL) (6,2%), and left upper lobe (LUL) (6%).

Conclusion

Our data showed the most common findings in HRCT were bronchial thickening ground-glass opacity, emphysema, and bronchiectasis, where these findings was dominantly found in LLL, RLL, RUL, and LUL, indicating its high tendency to dependent areas.

Chronic Microaspiration and Frailty: A Geriatric Smoking Gun?

Chronic microaspiration and diffuse aspiration bronchiolitis may account for some otherwise unexplained frailty in nursing home patients.

Animal Models of Aspiration Pneumonia

Appropriate animal models of aspiration pneumonia may be required for studying the mechanism of aspiration and aspiration-induced pneumonia. Animal models of AP allow us to investigate distinct types of pneumonia at various disease stages, studies that are not possible in patients. AP animal models should have features of bacterial pneumonia and swallowing abnormality.

Our animal model of aspiration, using recombinant E1-deleted Ad vectors, may be advantageous relative to earlier models for assessing the development of aspiration pneumonia in association with disturbed upper airway reflexes, since DNA virus infection of bronchiolar epithelial cells in the lower respiratory tract can be assessed by the localization and intensity of LacZ gene expression The other candidate model of aspiration was applied for the experimental stroke in mice induced by occlusion of the middle cerebral artery. Aspiration pneumonia was caused by intranasal application of a small amount of Streptococcus pneumoniae.

Acid pneumonitis is a major cause of sterile acute lung injury (ALI), resulting in acute respiratory distress syndrome (ARDS) or Mendelson’s syndrome. Several types of animal models of acid aspiration are available using a wide range of developed transgenic models.

Different types of animal models of both aspiration pneumonia and aspiration pneumonitis have considerably aided our understanding of disease pathogenesis and testing and developing of new treatment strategies.

New perspectives in aspiration community acquired Pneumonia

Introduction: Aspiration pneumonia is a subclass of community-acquired pneumonia that is expected to have an increasing contribution in mortality and morbidity, particularly in the elderly population over the next coming decades. While studies have revealed significant progress in identifying risk factors for aspiration pneumonia, the clinical presentation and diagnosis remain challenging to healthcare providers. Areas covered: We conducted a broad literature review using the MeSH heading in PubMed/MEDLINE of 'aspiration pneumonia' from January 1970 to July 2019. The understanding of the microbiology of aspiration pneumonia has evolved from a possible shift in the causative organisms away from anaerobes to traditional community-acquired pneumonia organisms. The importance of this shift is not yet known, but it has questioned the pathogenic role of anaerobes, appropriate anaerobic testing and the role of these pathogens in the pulmonary microbiome in patients with pneumonia. The identification of risk factors led to strategies to prevent or minimize the risk of aspiration pneumonia with moderate success. Expert opinion: Our expert opinion is that further research is needed to determine the role of the microbiome with aspiration pneumonia and patient risk factors. There is also a great need to develop clinical tools to help providers diagnose, treat, and prevent aspiration pneumonia.

A 68-Year-Old Man With Dyspnea on Exertion and Cough

A 68-year-old man with a history of chronic lymphocytic leukemia well controlled on ibrutinib, hypertension, obesity, and a remote history of smoking (10 pack-years) presented with increasing dyspnea on exertion and cough. He had previously finished two courses of oral antibiotics for his symptoms without significant improvement. On presentation, he had no fevers or sputum production.

Aerodigestive disorders in dogs evaluated for cough using respiratory fluoroscopy and videofluoroscopic swallow studies

Aerodigestive diseases, hybrid disorders representing a pathologic link between respiratory and alimentary tracts, may manifest with respiratory signs without gastrointestinal signs. These are underdiagnosed in dogs due to poor clinical recognition and diagnostic limitations. We hypothesize that a subset of dogs presenting for cough without gastrointestinal signs would have occult aerodigestive disorders identified using videofluoroscopic swallow study (VFSS). Data were retrospectively obtained from 31 client-owned dogs presenting for cough, with thoracic radiographs, and a VFSS between April 2015 and December 2017. Exclusion criteria were cough of cardiac origin or gastrointestinal signs within 6 months. Swallow study parameters included pharyngeal/esophageal motility, laryngeal obstruction/defects, penetration-aspiration, reflux, excessive aerophagia, megaesophagus (ME), lower-esophageal sphincter achalasia-like syndrome (LES-AS), and sliding hiatal hernia (HH). The median (interquartile range) duration of cough was 4 (2-8) months. Thoracic radiographs were unremarkable in 11 dogs, with aspiration pneumonia suspected in seven. In 25/31 dogs (81%), VFSS abnormalities were detected and some dogs had more than one defect: pharyngeal (n=10) or esophageal hypomotility (n=10), reflux (n=9), penetration-aspiration (n=8), excessive aerophagia (n=6), laryngeal obstruction (n=3), ME (n=3), HH (n=2), and LES-AS (n=1). A respiratory disorder causing cough was identified in 17 dogs with VFSS abnormalities (laryngeal obstruction/defect and airway disease including chronic or eosinophilic bronchitis, tracheal/mainstem bronchial collapse, bronchiectasis, and bronchomalacia). An alimentary disorder identified on VFSS in absence of a discrete respiratory disorder causing cough was diagnosed in eight dogs. In conclusion, canine aerodigestive disorders can manifest as cough without alimentary signs. VFSS is a useful diagnostic to determine the contribution of esophageal/gastrointestinal pathology in dogs with cough.

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

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

Aberrant right subclavian artery and bibasilar bronchiectasis: is there any association?

Dysphagia is the most common symptom in symptomatic patients with aberrant right subclavian artery (ARSA) and also the risk factor of aspiration, especially in elderly patients. We presented an 84 year-old female patient with dysphagia induced by the compression of ARSA to the adjacent structures. Recurrent pneumonia and bibasilar bronchiectasis were recorded in the association with ARSA. We concluded that elderly patient with ARSA should be evaluated the pulmonary complications such as aspiration pneumonia and bronchiectasis.

Imaging of Diseases of the Large Airways

Imaging of the large airways is key to the diagnosis and management of a wide variety of congenital, infectious, malignant, and inflammatory diseases. Involvement can be focal, regional, or diffuse, and abnormalities can take the form of masses, thickening, narrowing, enlargement, or a combination of patterns. Recognition of the typical morphologies, locations, and distributions of large airways disease is central to an accurate imaging differential diagnosis.

Dysphagia, dystussia, and aspiration pneumonia in elderly people

Despite the development and wide distribution of guidelines for pneumonia, death from pneumonia is increasing due to population aging. Conventionally, aspiration pneumonia was mainly thought to be one of the infectious diseases. However, we have proven that chronic repeated aspiration of a small amount of sterile material can cause the usual type of aspiration pneumonia in mouse lung. Moreover, chronic repeated aspiration of small amounts induced chronic inflammation in both frail elderly people and mouse lung. These observations suggest the need for a paradigm shift of the treatment for pneumonia in the elderly. Since aspiration pneumonia is fundamentally based on dysphagia, we should shift the therapy for aspiration pneumonia from pathogen-oriented therapy to function-oriented therapy. Function-oriented therapy in aspiration pneumonia means therapy focusing on slowing or reversing the functional decline that occurs as part of the aging process, such as "dementia → dysphagia → dystussia → atussia → silent aspiration". Atussia is ultimate dysfunction of cough physiology, and aspiration with atussia is called silent aspiration, which leads to the development of life-threatening aspiration pneumonia. Research pursuing effective strategies to restore function in the elderly is warranted in order to decrease pneumonia deaths in elderly people.

Diffuse aspiration bronchiolitis: analysis of 20 consecutive patients

OBJECTIVE

Aspiration can cause a variety of pulmonary syndromes, some of which are not well recognized. The objective of this study was to assess the demographic, clinical, radiological, and histopathological correlates of diffuse aspiration bronchiolitis (DAB), a bronchiolocentric disorder caused by recurrent aspiration.

METHODS

This was a retrospective study of 20 consecutive patients with DAB seen at the Mayo Clinic in Rochester, Minnesota, between January 1, 1998 and June 30, 2014.

RESULTS

The median age of the patients was 56.5 years (range, 22-76 years), and the male/female ratio was 2.3:1.0. In 18 patients, the diagnosis of DAB was based on the results of a lung biopsy; in the 2 remaining patients, it was based on clinical and radiological features, together with documented aspiration observed in a videofluoroscopic swallow study. In 19 patients (95%), we identified predisposing factors for aspiration, including gastroesophageal reflux disease (GERD), drug abuse, and dysphagia. Common presenting features included cough, sputum production, dyspnea, and fever. Twelve patients (60%) had a history of recurrent pneumonia. In all of the patients, chest CT revealed bilateral pulmonary infiltrates consisting of micronodules and tree-in-bud opacities. In the majority of patients, interventions aimed at preventing recurrent aspiration (e.g., anti-GERD therapies) led to improvement in the symptoms of DAB.

CONCLUSIONS

Young to middle-aged subjects with recognizable predisposing factors for aspiration and who report a history of recurrent pneumonia are at increased risk for DAB. Although DAB is not well recognized, certain chest CT features are characteristic of the disorder.

Bronchiectasis: Mechanisms and Imaging Clues of Associated Common and Uncommon Diseases

Bronchiectasis is permanent irreversible dilatation of the airways and occurs in a variety of pathologic processes. Recurrent infection and inflammation and the resulting chemical and cellular cascade lead to permanent architectural changes in the airways. Bronchiectasis can confer substantial potential morbidity, usually secondary to recurrent infection. In severe cases of bronchiectasis, massive hemoptysis can lead to death. Thin-section computed tomography is the most sensitive imaging modality for the detection of bronchiectasis; findings include bronchial diameter exceeding that of the adjacent pulmonary artery and lack of normal tapering of terminal bronchioles as they course toward the lung periphery. The authors will review various causes of bronchiectasis, including common causes, such as recurrent infection or aspiration, and uncommon causes, such as congenital immunodeficiencies and disorders of cartilage development. The authors will also present an approach emphasizing the distribution (apical versus basal and central versus peripheral) and concomitant findings, such as nodules, cavities, and/or lymphadenopathy, that can assist in narrowing the differential diagnosis. Although an adequate understanding of these underlying causes in conjunction with their specific imaging appearances will allow radiologists to more confidently determine the process causing this common radiologic finding, clinical history and patient demographic characteristics play an integral role in determining a pertinent and concise differential diagnosis.

Chronic pulmonary microaspiration: high-resolution computed tomographic findings in 13 patients

PURPOSE

The aim of the study was to describe the high-resolution computed tomography (CT) manifestations of chronic pulmonary microaspiration, a condition characterized by recurrent subclinical aspiration of small droplets of gastric contents or foreign particles into the lungs.

MATERIALS AND METHODS

We reviewed the CT findings in 13 consecutive patients with clinical (n=13) and histologic (n=1) diagnosis of chronic pulmonary microaspiration. Twelve patients presented with persistent cough, but none had a clinical history of acute aspiration. One patient was asymptomatic. All patients had volumetric CT of the chest reconstructed using thin sections (1 to 1.3 mm) at the time of diagnosis. The CT scans were interpreted by 3 chest radiologists who reached a final decision by consensus.

RESULTS

All 13 patients had centrilobular nodules and ground-glass opacities that involved mainly the dependent lung regions in 11 patients and had a random distribution in 2. Other common findings included branching opacities (n=10), small foci of consolidation (n=7), septal lines (n=5), and bronchiectasis (n=7). The 13 patients had at least 1 risk factor for aspiration including gastroesophageal reflux (n=9), hiatus hernia (n=6), esophageal dysfunction (n=3), oropharyngeal dysphagia (n=1), esophageal carcinoma (n=1), and use of sedatives (n=2).

CONCLUSIONS

The high-resolution CT manifestations of chronic pulmonary microaspiration consist mainly of centrilobular nodules and ground-glass opacities that tend to involve predominately the dependent regions. Branching opacities and small foci of consolidation are seen in the majority of cases.

Aspiration-related lung diseases

Aspiration is a common but underrecognized clinicopathologic entity, with varied radiographic manifestations. Aspiration represents a spectrum of diseases, including diffuse aspiration bronchiolitis, aspiration pneumonitis, airway obstruction by foreign body, exogenous lipoid pneumonia, interstitial fibrosis, and aspiration pneumonia with or without lung abscess formation. Many patients who aspirate do not present with disease, suggesting that pathophysiology is related to a variety of factors, including decreased levels of consciousness, dysphagia, impaired mucociliary clearance, composition of aspirate, and impaired host defenses. In this pictorial essay, we will review the different types of aspiration lung diseases, focusing on their imaging features and differential diagnosis.

Aspiration-related pulmonary syndromes

Aspiration of foreign matter into the airways and lungs can cause a wide spectrum of pulmonary disorders with various presentations. The type of syndrome resulting from aspiration depends on the quantity and nature of the aspirated material, the chronicity, and the host responses. Aspiration is most likely to occur in subjects with a decreased level of consciousness, compromised airway defense mechanisms, dysphagia, gastroesophageal reflux, and recurrent vomiting. These aspiration-related syndromes can be categorized into airway disorders, including vocal cord dysfunction, large airway obstruction with a foreign body, bronchiectasis, bronchoconstriction, and diffuse aspiration bronchiolitis, or parenchymal disorders, including aspiration pneumonitis, aspiration pneumonia, and exogenous lipoid pneumonia. In idiopathic pulmonary fibrosis, aspiration has been implicated in disease progression and acute exacerbation. Aspiration may increase the risk of bronchiolitis obliterans syndrome in patients who have undergone a lung transplant. Accumulating evidence suggests that a causative role for aspiration is often unsuspected in patients presenting with aspiration-related pulmonary diseases; thus, many cases go undiagnosed. Herein, we discuss the broadening spectrum of these pulmonary syndromes with a focus on presenting features and diagnostic aspects.

The spectrum of lung disease due to chronic occult aspiration

RATIONALE

Chronic aspiration of small volumes of oral and gastric contents can lead to lung disease. This process is less familiar than the acute aspiration syndromes, which can create confusion in terminology as well as with radiologic and pathologic definitions.

OBJECTIVES

In this study we analyze a series of cases of patients with chronic occult aspiration to better define the disease process.

METHODS

Twenty-five patients with chronic occult aspiration as defined pathologically on lung biopsy were studied by means of retrospective review of their case records. Clinical associations and radiologic and pathologic patterns were noted.

MEASUREMENTS AND MAIN RESULTS

Among patients with chronic occult aspiration, there was a high prevalence of gastroesophageal reflux disease (96%), esophageal dysfunction (40%), oropharyngeal/laryngeal dysfunction (40%), hiatal hernias (32%), obstructive sleep apnea (32%), and obesity (52%). The radiologic presentation was typically one of multilobar centrilobular nodularity, tree-in-bud, and airway thickening, with a subset of patients having evidence of fibrosis. The disease presented pathologically with exogenous lipoid pneumonia, poorly formed granulomas, and foreign body-type multinucleated giant cells with or without foreign material. Pathologic fibrosis was also seen.

CONCLUSION

In this study, chronic occult aspiration was associated with a number of comorbid conditions and a spectrum of radiologic and pathologic patterns, which in some patients included fibrosis.

Tree-in-bud pattern in central lung cancer: CT findings and pathologic correlation

OBJECTIVES

Tree-in-bud (TIB) pattern can be found with central lung cancer on chest CT scans. However, few reports have described it so far. We aim to determine its incidence, CT findings and pathologic basis.

MATERIALS AND METHODS

652 consecutive patients with confirmed central lung cancer were enrolled in our study. The incidence, CT findings and pathologic features of TIB pattern were analyzed retrospectively.

RESULTS

In total, TIB pattern was found in 22.5% (147/652) of patients. It was more common in patients with squamous cell carcinoma than those with non-squamous cell carcinoma (P=0.000). The most important associated CT finding was obstructive bronchial mucoid impaction distal to the cancer (100%, 147/147), followed by consolidation and ground-glass opacities (62.6%, 92/147). TIB pattern was confined to the areas of lung supplied by the involved bronchi (100%, 147/147) and had a focal distribution predominantly (94.6%, 139/147). Pathologically, it correlated with bronchiolectasis, bronchiolar lumen filled by mucus and inflammatory exudates, wall thickening with inflammatory cells infiltration.

CONCLUSIONS

TIB pattern is commonly detected in central lung squamous cell carcinoma on thoracic CT scan. It usually has a localized distribution with a predominant associated CT finding of obstructive bronchial mucoid impaction. This pattern corresponds to the mucoid impaction of bronchioles and bronchiolitis pathologically. A full understanding of TIB pattern in central lung cancer can be useful in preventing diagnostic errors.

Detection failure rate of chest radiography for the identification of nursing and healthcare-associated pneumonia

AIM

To clarify the detection failure rate of chest radiography for the identification of nursing and healthcare-associated pneumonia (NHCAP), we compared high-resolution computed tomography (HRCT) with chest radiography simultaneously for patients with clinical symptoms and signs leading to a suspicion of NHCAP.

METHODS

We analyzed 208 NHCAP cases and compared them based on four groups defined using NHCAP criteria, patients who were: Group A) resident in an extended care facility or nursing home; Group B) discharged from a hospital within the preceding 90 days; Group C) receiving nursing care and had poor performance status; and Group D) receiving regular endovascular treatment.

RESULTS

Chest radiography was inferior to HRCT for the identification of pneumonia (149 vs 208 cases, p < 0.0001). Among the designated NHCAP criteria, chest radiography identified pneumonia cases at a significantly lower frequency than HRCT in Group A (70 vs 97 cases, p = 0.0190) and Group C (86 vs 136 cases, p < 0.0001). The detection failure rate of chest radiography differed among NHCAP criteria; 27.8% in Group A, 26.5% in Group B, 36.7% in Group C and 5.8% in Group D. Cerebrovascular disease and poor functional status were significantly more frequent in patients in Groups A and C compared with those in Groups B and D.

CONCLUSIONS

Physicians may underestimate pneumonia shadow in chest radiographs in patients with NHCAP, and the detection failure rate of chest radiography differed among NHCAP criteria. Poor functional status may correlate with the low accuracy of chest radiography in diagnosing pneumonia.

Electrophysiological evaluation of oropharyngeal Dysphagia in Parkinson's disease

Parkinson’s disease (PD) is a chronic, neurodegenerative movement disorder that typically affects elderly patients. Swallowing disorders are highly prevalent in PD and can have grave consequences, including pneumonia, malnutrition, dehydration and mortality. Neurogenic dysphagia in PD can manifest with both overt clinical symptoms or silent dysphagia. Regardless, early diagnosis and objective follow-up of dysphagia in PD is crucial for timely and appropriate care for these patients. In this review, we provide a comprehensive summary of the electrophysiological methods that can be used to objectively evaluate dysphagia in PD. We discuss the electrophysiological abnormalities that can be observed in PD, their clinical correlates and the pathophysiology underlying these findings.

Respiratory dysfunction is common in patients with achalasia and improves after pneumatic dilation

BACKGROUND

Dysphagia, regurgitation, and chest pain are common achalasia, with a variable report of pulmonary symptoms possibly due to micro-aspiration. Pneumatic dilation (PD) may improve pulmonary function. Data on pulmonary dysfunction among achalasia patients are scanty, and the effect of PD is unknown.

AIM

To evaluate pulmonary dysfunction in patients with achalasia based on clinical and radiologic evaluation and spirometry and to study the effect of PD at 1-month follow-up.

METHODS

Patients with achalasia (diagnosed using high-resolution manometry and the Chicago classification) were evaluated prospectively by spirometry before (n = 38) and 1 month after PD (n = 31). All patients received a chest X-ray, and patients with respiratory abnormality before PD received high-resolution computed tomography of the thorax.

RESULTS

Of the 38 patients, 17 and 21 had type I and II achalasia, respectively. The respiratory symptoms, such as pharyngeal symptoms [27/38 (71 %) vs. 8/31 (26 %); P = 0.0001], cough [23/38 (60.5 %) vs. 5/31 (16 %), P = 0.0001], and dyspnea [8/38 (21 %) vs. 0/31 (0 %), P = 0.006], improved after treatment with PD. Spirometry showed abnormalities in 17/38 (45 %) patients before and in 8/15 (53 %) after PD. Median FEV(1), FVC, PEFR, and percentage of predicted MEF(25-75), improved from 78 % (36-85), 74 % (48-100), 62 % (18-72), and 48 % (15-66) before to 83 % (58-94), 86 % (55-99), 69 % (38-81), and 59 % (33-78) after PD, respectively (P < 0.05 for all).

CONCLUSION

Respiratory symptoms and spirometry abnormalities are common in patients with achalasia and improved after successful PD.

Healthcare-associated Pneumonia and Aspiration Pneumonia

Healthcare-associated pneumonia (HCAP) is a new concept of pneumonia proposed by the American Thoracic Society/Infectious Diseases Society of America in 2005. This category is located between community-acquired pneumonia and hospital-acquired pneumonia with respect to the characteristics of the causative pathogens and mortality, and primarily targets elderly patients in healthcare facilities. Aspiration among such patients is recognized to be a primary mechanism for the development of pneumonia, particularly since the HCAP guidelines were published. However, it is difficult to manage patients with aspiration pneumonia because the definition of the condition is unclear, and the treatment is associated with ethical aspects. This review focused on the definition, prevalence and role of aspiration pneumonia as a prognostic factor in published studies of HCAP and attempted to identify problems associated with the concept of aspiration pneumonia.

Bronchiolitis: adopting a unifying definition and a comprehensive etiological classification

Bronchiolitis is an inflammatory and potentially fibrosing condition affecting mainly the intralobular conducting and transitional small airways. Secondary bronchiolitis participates in disease process of the airways and/or the surrounding lobular structures in the setting of several already defined clinical entities, mostly of known etiology, and occurs commonly. Primary or idiopathic bronchiolitis dominates and characterizes distinct clinical entities, all of unknown etiology, and occurs rarely. Secondary bronchiolitis regards infections, hypersensitivity disorders, the whole spectrum of smoking-related disorders, toxic fumes and gas inhalation, chronic aspiration, particle inhalation, drug-induced bronchiolar toxicities, sarcoidosis and neoplasms. Idiopathic or primary bronchiolitis defines clinicopathologic entities sufficiently different to be designated as separate disease entities and include cryptogenic constrictive bronchiolitis, diffuse panbronchiolitis, diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, neuroendocrine hyperplasia in infants, bronchiolitis obliterans syndrome in lung and allogeneic hematopoietic cell transplantation, connective tissue disorders, inflammatory bowel disease and bronchiolitis obliterans organizing pneumonia. Most of the above are pathological descriptions used as clinical diagnosis. Acute bronchiolitis, though potentially life threatening, usually regresses. Any etiology chronic bronchiolitis contributes to morbidity and/or mortality if it persists and/or progresses to diffuse airway narrowing and distortion or complete obliteration. Bronchiolitis in specific settings leads to bronchiolectasis, resulting in bronchiectasis.

Nine pulmonary aspiration syndrome cases of atypical clinical presentation, in which the final diagnosis was obtained by histological examinations

BACKGROUND

While pulmonary aspiration syndrome (PAS) is primarily clinically diagnosed, atypical PAS cases can be misdiagnosed clinically and are more accurately diagnosed histologically. To elucidate clinicopathological features of these rare cases, we examined PAS cases determined by histological examination of transbronchial lung biopsy (TBLB) specimens.

METHODS

Of 6105 TBLB cases investigated from 1990 to 2007, 11 were diagnosed as PAS based on histology. Of these, we examined 9 records in detail, as the medical records for 2 cases were unavailable.

RESULTS

Histopathological findings indicated 8 patients with aspiration pneumonia and 1 with diffuse aspiration bronchiolitis. However, the pre-bronchoscopy diagnoses included lung cancer, mycobacteriosis, organizing pneumonia, repetitive pneumonia, fungal infection, and interstitial pneumonia. PAS was not considered before TBLB. Only 4 of the 9 patients developed subjective symptoms including fever and cough with sputum production. Laboratory findings demonstrated elevation of white blood cell (WBC) count in only 1 patient and elevation of C reactive protein (CRP) level in 4 patients. Radiographic examination revealed abnormal findings in the dorsal right lower lobes, which was the most vulnerable site for aspiration pneumonia, and also in the upper and ventral portions of the lung. Although the characteristic findings of PAS were scarce, all patients had conditions predisposing to aspiration; i.e., gastrectomy, excessive alcohol drinking, post-cerebral infarction, and sinobronchial syndrome.

CONCLUSIONS

We diagnosed 9 PAS patients on the basis of histological findings that were distinct from clinical findings. Despite presenting with variable symptoms and laboratory and radiographic findings, they all exhibited predisposing factors to aspiration.

Pepsin and bile acid concentrations in sputum of mustard gas exposed patients

BACKGROUND/AIM

Gastro-esophageal reflux has been suggested to be associated with several pulmonary complications such as asthma, and post-transplant bronchiolitis obliterans (BO). Pepsin or bile salts in the sputum is shown to be an optimal molecular marker of gastric contents macro/micro aspiration. In this study, we investigated sputum pepsin as a marker of micro-aspiration in sulfur mustard (SM) exposed cases compared to healthy controls.

MATERIALS AND METHODS

In a case controlled study, 26 cases with BO and 12 matched healthy controls were recruited and all cases were symptomatic and their exposure to SM was previously documented during Iran-Iraq conflict. Pepsin levels in sputum and total bile acids were measured using enzymatic assay. The severity of respiratory disorder was categorized based upon the spirometric values.

RESULT

The average concentration of pepsin in sputum was higher in the case group (0.29 ± 0.23) compared with healthy subjects (0.13 ± 0.07; P ± 0.003). Moreover, the average concentration of bile acids in the sputum cases was not significantly different in comparison to the controls ( P = 0.5).

CONCLUSION

Higher pepsin concentrations in sputum of SM exposed patients compared with healthy control subjects indicate the occurrence of significantly more gastric micro-aspiration in SM exposed patients.

Extra-esophageal manifestations of gastroesophageal reflux disease: controversies between epidemiology and clicnic

Gastroesophageal reflux disease (GERD) is widely associated with asthma, chronic cough, and laryngitis. Many studies have focused on acidic reflux; however, acid is just one of many factors that can cause pulmonary injury. The discrepancy between the high frequency of GERD in asthmatic patients and the ineffective reflux therapy outcomes in these patients suggests that GERD may cause injury through other mechanisms, such as pepsinogen, pepsin, bile salts, or other components of reflux materials, instead of the acid. Research using appropriate and innovative methodologies to investigate these potential inflammatory agents in patients with GERD is required to determine the underlying factors associated with pulmonary disorders in these patients.

Computed tomography findings of aspiration pneumonia in 53 patients

AIM

No large case series has so far shown the chest computed tomography (CT) features in patients with aspiration pneumonia, despite the fact that aspiration pneumonia is the most common pulmonary disease in the elderly and is regarded as gravity-dependent pneumonia. The aim of the present study was to elucidate the CT features based on the patients' status in patients with dysphagia-associated aspiration pneumonia.

METHODS

A total of 53 patients, who were hospitalized because of pneumonia and subsequently confirmed to have dysphagia by videofluorography, were entered into this study. The CT findings were independently evaluated by two radiologists who were unaware of the patients' clinical information. The relationships between the patients' status and the CT patterns of pneumonia or their distributions were analyzed.

RESULTS

There were eight patients (15%) with lobar pneumonia, 36 patients (68%) with bronchopneumonia and nine patients (17%) with bronchiolitis. Posterior lung predominance was seen in 49 patients (92%). In the craniocaudal observation, lower lung predominance was found in 25 patients (47%) and diffuse distribution was seen in 28 patients (53%). A decreased performance status was significantly associated with a diffuse distribution (P=0.039).

CONCLUSIONS

Aspiration pneumonia more frequently presented as a bronchopneumonia pattern followed by a bronchiolitis pattern on CT. Their distributions were characterized by gravity dependence, and anterior- or upper lung-limited pneumonia might not be due to dysphagia-associated pneumonia.

Investigation of eating actions of people with dementia from the viewpoint of self-awareness

The key to improve the quality of life of people with dementia and caregivers is whether caregivers can understand the meanings of the puzzling words and deeds of people with dementia. Therefore, 2 of the authors observed and wrote down the puzzling words and deeds of 28 people with dementia in eating scenes, and these words and deeds were interpreted using our original model consisting of "theory of mind," "self-evaluation," and "self-consciousness." The results indicated that the bases for why caregivers perceive the words and deeds of people with dementia in eating scenes as puzzling are (1) those unable to pass the task of self-evaluation cannot evaluate their own eating situations in comparison with social standards, and the food culture collapses and (2) those unable to pass the task of self-consciousness cannot perceive through their senses.

Gastroesophageal reflux incites interstitial lung disease in systemic sclerosis: clinical, radiologic, histopathologic, and treatment evidence

OBJECTIVES

Interstitial lung disease (ILD) is currently the main cause of death in systemic sclerosis (SSc) and has an unknown pathogenesis. Gastroesophageal reflux (GER) has been strongly implicated as a cause of ILD in several lung diseases, including SSc-ILD. This review summarizes clinical, radiologic, histopathologic, and treatment aspects of GER in SSc-ILD.

METHODS

The PubMed database was searched using the following keywords: "systemic sclerosis, scleroderma, interstitial lung disease, and gastroesophageal reflux." The research was limited to English-language studies that included SSc patients with ILD.

RESULTS

Pulmonary function tests were related with the presence of GER in several esophageal functional tests (esophageal endoscopy, pH monitoring, and manometric analysis). Regarding the histopathologic data, a pattern called centrilobular fibrosis was described in 21% of 28 lung biopsies, with a bronchocentric distribution and with an intraluminal content resembling gastric fluid. Radiologic evidence of esophageal dilation is very frequent in SSc patients, and consolidation with a patchy distribution was almost exclusively found in SSc patients with centrilobular fibrosis lung pattern. Furthermore, high levels of serum KL-6, a marker of epithelial injury, are indicative of active ILD in SSc disease.

CONCLUSIONS

The association of GER with SSc-ILD is strongly supported by several studies. An aggressive treatment for reflux is recommended in all SSc patients with ILD; however, future studies need to be performed to prove a long-term benefit.

Bronchiolar disorders: a clinical-radiological diagnostic algorithm

Bronchiolar disorders are generally difficult to diagnose because most patients present with nonspecific respiratory symptoms of variable duration and severity. A detailed clinical history may point toward a specific diagnosis. Pertinent clinical questions include history of smoking, collagen vascular disease, inhalational injury, medication usage, and organ transplant. It is important also to evaluate possible systemic and pulmonary signs of infection, evidence of air trapping, and high-pitched expiratory wheezing, which may suggest small airways involvement. In this context, pulmonary function tests and plain chest radiographs may demonstrate abnormalities; however, they rarely prove sufficiently specific to obviate bronchoscopic or surgical biopsy. Given these limitations, in our experience, high-resolution CT (HRCT) scanning of the chest often proves to be the most important diagnostic tool to guide diagnosis in these difficult cases, because different subtypes of bronchiolar disorders may present with characteristic image findings. Three distinct HRCT patterns in particular are of value in assisting differential diagnosis. A tree-in-bud pattern of well-defined nodules is seen primarily as a result of infectious processes. Ill-defined centrilobular ground-glass nodules point toward respiratory bronchiolitis when localized in upper lobes in smokers or subacute hypersensitivity pneumonitis when more diffuse. Finally, a pattern of mosaic attenuation, especially when seen on expiratory images, is consistent with air-trapping characteristic of bronchiolitis obliterans or constrictive bronchiolitis. Based on an appreciation of the critical role played by HRCT scanning, this article provides clinicians with a practical algorithmic approach to the diagnosis of bronchiolar disorders.

Aspiration pneumonia

Aspiration pneumonia is diagnosed upon confirmation of inflammatory findings in the lungs and overt aspiration (apparent aspiration) or a condition in which aspiration is strongly suspected (abnormal swallowing function and dysphagia). In hospital-acquired pneumonia, this occurs as one consequence of frequent silent aspiration. In the diagnosis of aspiration pneumonia, evaluation of the risk of silent aspiration during the night and evaluation of swallowing function are important. The causative microorganisms in aspiration pneumonia, similar to community-acquired pneumonia, are basically thought to be bacteria residing in the oral cavity, such as pneumococcus, Haemophilus influenzae, Staphylococcus aureus and anaerobes. Hospital-acquired aspiration pneumonia often occurs with no distinction between apparent and silent aspiration, and in many cases, aspiration of foreign substances is serious when dysphagia itself is severe. In the treatment of aspiration pneumonia, use of antimicrobials for the pneumonia itself and early measures to prevent aspiration are important.