Diffuse pulmonary fibrosis and hiatus hernia

Emerging cellular and molecular determinants of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF), the most common form of idiopathic interstitial pneumonia, is a progressive, irreversible, and typically lethal disease characterized by an abnormal fibrotic response involving vast areas of the lungs. Given the poor knowledge of the mechanisms underpinning IPF onset and progression, a better understanding of the cellular processes and molecular pathways involved is essential for the development of effective therapies, currently lacking. Besides a number of established IPF-associated risk factors, such as cigarette smoking, environmental factors, comorbidities, and viral infections, several other processes have been linked with this devastating disease. Apoptosis, senescence, epithelial-mesenchymal transition, endothelial-mesenchymal transition, and epithelial cell migration have been shown to play a key role in IPF-associated tissue remodeling. Moreover, molecules, such as chemokines, cytokines, growth factors, adenosine, glycosaminoglycans, non-coding RNAs, and cellular processes including oxidative stress, mitochondrial dysfunction, endoplasmic reticulum stress, hypoxia, and alternative polyadenylation have been linked with IPF development. Importantly, strategies targeting these processes have been investigated to modulate abnormal cellular phenotypes and maintain tissue homeostasis in the lung. This review provides an update regarding the emerging cellular and molecular mechanisms involved in the onset and progression of IPF.

Chronic, Silent Microaspiration Masquerading as Interstitial Lung Disease

Chronic, silent microaspiration is a common but underrecognized pathologic process in pulmonary medicine. The clinical presentation is variable and diagnosis can be challenging. We present the case of a 55-year-old woman with known emphysema, who was referred to us for progressive respiratory failure that was unresponsive to therapy. The patient had 9 hospital admissions in the preceding 5 months and was treated with multiple courses of antibiotics and systemic steroid therapy for a diagnosis of cryptogenic organizing pneumonia. The steroid therapy was complicated by 51 pounds of weight gain. She had conversational as well as profound exertional shortness of breath. Physical examination revealed a woman in moderate distress and bilateral diffuse wheezing and rhonchi. Computed tomography of the chest revealed areas of bronchocentric consolidation and bronchial wall thickening in the bilateral lower lobes. She underwent surgical lung biopsy and the histopathology was consistent with chronic aspiration pneumonia.

Gastroesophageal Reflux and Idiopathic Pulmonary Fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease of unknown origin that affects about 40,000 new patients every year in the USA. Albeit the disease is labelled as idiopathic, it is thought that pathologic reflux, often silent, plays a role in its pathogenesis through a process of microaspiration of gastric contents.

AIMS

The aim of this study was to review the available evidence linking reflux to IPF, and to study the effect of medical and surgical therapy on the natural history of this disease.

RESULTS

Medical therapy with acid-reducing medications controls the production of acid and has some benefit. However, reflux and aspiraion of weakly acidic or alkaline gastric contents can still occur. Better results have been reported after laparoscopic anti-reflux surgery, as this form of therapy re-establishes the competence of the lower esophageal sphincter, therefore stopping any type of reflux.

CONCLUSIONS

A phase II NIH study in currently in progress in the USA to determine the role of antireflux surgery in patients with GERD and IPF. The hope is that this simple operations might alter the natural history of IPF, avoiding progression and the need for lung transplantation.

Diffuse parenchymal lung disease with micro aspirations in presence of hiatal hernia

There has been controversy regarding the relationship between gastroesophageal reflux, microaspiration, and idiopathic pulmonary fibrosis (IPF). In the last decade, there is increasing evidence supporting a relationship between gastroesophageal reflux, microaspiration, and IPF. The presence of hiatal hernia further propagates microaspirations. Surgical management of hiatal hernia plays a vital role in the treatment.

Effects of bile acids on human airway epithelial cells: implications for aerodigestive diseases

Gastro-oesophageal reflux and aspiration have been associated with chronic and end-stage lung disease and with allograft injury following lung transplantation. This raises the possibility that bile acids may cause lung injury by damaging airway epithelium. The aim of this study was to investigate the effect of bile acid challenge using the immortalised human bronchial epithelial cell line (BEAS-2B). The immortalised human bronchial epithelial cell line (BEAS-2B) was cultured. A 48-h challenge evaluated the effect of individual primary and secondary bile acids. Post-challenge concentrations of interleukin (IL)-8, IL-6 and granulocyte-macrophage colony-stimulating factor were measured using commercial ELISA kits. The viability of the BEAS-2B cells was measured using CellTiter-Blue and MTT assays. Lithocholic acid, deoxycholic acid, chenodeoxycholic acid and cholic acid were successfully used to stimulate cultured BEAS-2B cells at different concentrations. A concentration of lithocholic acid above 10 μmol·L-1 causes cell death, whereas deoxycholic acid, chenodeoxycholic acid and cholic acid above 30 μmol·L-1 was required for cell death. Challenge with bile acids at physiological levels also led to a significant increase in the release of IL-8 and IL6 from BEAS-2B. Aspiration of bile acids could potentially cause cell damage, cell death and inflammation in vivo. This is relevant to an integrated gastrointestinal and lung physiological paradigm of chronic lung disease, where reflux and aspiration are described in both chronic lung diseases and allograft injury.

The prevalence of gastro-esophageal reflux disease and esophageal dysmotility in Chinese patients with idiopathic pulmonary fibrosis

Background

The cause of idiopathic pulmonary fibrosis (IPF) remains unknown, yet gastro-esophageal reflux disease (GERD) is highly prevalent in this population. GERD prevalence was studied, and esophageal function tests (EFT) were assessed in Chinese IPF patients.

Methods

We prospectively studied 69 IPF patients who undertook both stationary High Resolution esophageal Manometry/Impedance (HRiM) and 24-hour esophageal Multi-Channel Intraluminal Impedance with pH Recordings (MII/pH). Patients were divided into GERD+ and GERD- groups according to pH results. Controls were HRiM treated healthy volunteers, and patients without IPF received HRiM and MII/pH diagnosed with GERD.

Results

69 IPF patients, 62 healthy volunteers, and 88 IPF negative GERD patients were selected. GERD prevalence in IPF was 43/69 (62.3%), and 58.1% of patients presented with at least one typical symptom. Symptoms had a sensitivity of 58.1%, a specificity of 61.6%, a positive predictive value of 71.4% and a negative predictive of 47.1%. Compared with healthy volunteers, IPF patients had significantly decreased lower esophageal sphincter pressure (LESP), upper esophageal sphincter pressure (UESP) and complete bolus transit rate (CBTR). By contrast, IPF patients had increased total bolus transit time and prevalence of weak peristalsis. MII/pH showed that one third of IPF patients had abnormal distal and proximal reflux, especially non-acid reflux. Compared with GERD patients without IPF, GERD patients with IPF had significantly decreased CBTR and UESP with increased bolus exposure time.

Conclusions

GERD prevalence in IPF was high, but symptoms alone were an unreliable predictor of reflux. IPF patients had lower LESP and UESP, impaired esophageal peristalsis and bolus clearance function with more proximal reflux events.

Physiology of sleep and breathing before and after lung transplantation

During the past 20 years, lung transplantation (LTX) has evolved and it is now accepted as a mainstream modality for care of patients with severe life-threatening respiratory diseases that are refractory to maximal conventional therapies. Improvements in surgical techniques and in antirejection medications have resulted in prolonged survival in these patients. Several studies have explored quality of life after LTX and its improvement has been noted especially in the early period between 3 and 6 months. This article discusses the salient features of the physiology of breathing and sleep disturbances before and after LTX and its alterations during sleep.

Reflux esophagitis in war-related sulfur mustard lung disease

Background Sulfur mustard (SM) has acute and chronic effects on skin and mucosal surfaces. The aim of the study was to evaluate the frequency of esophagitis in a historical cohort of veterans who had been exposed to SM in Iran-Iraq war nearly 25 years ago.

METHODS

One hundred two veterans with dyspepsia and/or heartburn underwent esophago-gastroduodenoscopy. Of them, 52 cases had been exposed to SM and had chronic mustard lung disease. Controls included 50 veterans without SM exposure. Esophagitis was defined according to standard criteria.

RESULTS

81.6% of cases and 70.6% of controls had heart burn and/or regurgitation (p= 0.224). Esophagitis was seen in 40% of cases and 26.5% of controls (p= 0.155).

CONCLUSION

Based on our findings, SM exposure seems not to be associated with increased esophagitis.

The pulmonary side of reflux disease: from heartburn to lung fibrosis

INTRODUCTION

Gastroesophageal reflux disease (GERD) is the most prevalent gastrointestinal disorder in the USA. Heartburn is the symptom most commonly associated with this disease, and the highly commercialized medical treatment directed toward relief of this symptom represents a 10-billion-dollar-per-year industry.

DISCUSSION

Unfortunately, there is often little awareness that GERD can be potentially a lethal disease as it can cause esophageal cancer. Furthermore, there is even less awareness about the relationship between GERD and respiratory disorders with the potential for severe morbidity and even mortality.

Depression in patients with idiopathic pulmonary fibrosis

Depression carries enormous global morbidity and is 1.5–7 times likelier to occur in individuals with chronic illness than in the general population. Idiopathic pulmonary fibrosis (IPF) has a rising incidence with a severe impact on quality of life. An indication of the prevalence of depression in this group is therefore of paramount interest. A prospective study was performed. A total of 118 participants with IPF who attended the interstitial lung disease clinic in Ninewells Hospitals, Dundee, Scotland, from May 2010 to September 2011 were recruited. Informed consent was obtained. The male to female ratio was 60:58. The Wakefield Self-assessment of Depression Inventory was used (scores ≥15 denote a depressed state). Pulmonary function tests were measured to correlate disease severity with depression scores. Of them, 58 patients had significant depressive symptoms scoring ≥15; only nine were taking antidepressant medication. The mean depression score of female participants was 15.0 ± 0.77 (SD 5.9), compared with a mean male score of 13.1 ± 0.99 (SD 7.5). Disease severity, age, duration since diagnosis and number of co-morbidities were not significantly correlated with depression. The study population had a high prevalence of depressive symptoms. Medical therapy for pulmonary fibrosis is limited and therefore palliation of symptoms and pulmonary rehabilitation form the main strategy for management. Depression should be actively screened in patients with IPF.

GERD related micro-aspiration in chronic mustard-induced pulmonary disorder

BACKGROUND AND AIM

Bronchiolitis obliterans (BO) is the main pulmonary involvement resulting from sulfur mustard (SM) gas exposure that was used against Iranian civilians and military forces during the Iran-Iraq war. The present study aimed to investigate the prevalence of gastro-esophageal reflux (GER) and gastric micro-aspiration in SM gas injured patients with chronic pulmonary diseases and recurrent episodes of exacerbations.

MATERIALS AND METHODS

This cross-sectional study was done at Baqiyatallah University of Medical Sciences, Tehran, Iran. Gastric micro-aspiration and GER were assessed in the enrolled patients by assessing bile acids, pepsin and trypsin in their bronchoalveolar lavage fluid.

RESULTS

Our result showed that bile acids were found to be high in 21.4% patients, and low in 53.6% of patients. Only in 16% patients, no bile was detected in the BALF. Trypsin and pepsin were detected in BAL fluid of all patients.

CONCLUSION

Most of BO patients after exposure to SM suffer GER, while none the etiologic factors of GER in post lung transplant BO are present. It would be hypothesized that GER per se could be considered as an aggregative factor for exacerbations in patients. Further studies will provide more advances to better understanding of pathophysiological mechanism regarding GER and BO and treatment.

Interstitial lung disease and gastroesophageal reflux disease: key role of esophageal function tests in the diagnosis and treatment

CONTEXT

Gastroesophageal reflux disease (GERD) is common in patients with respiratory disorders and interstitial lung fibrosis from diverse disease processes. However, a cause-effect relationship has not been well demonstrated. It is hypothesized that there might be more than a coincidental association between GERD and interstitial lung damage. There is still confusion about the diagnostic steps necessary to confirm the presence of GERD, and about the role of effective control of GERD in the natural history of these respiratory disorders.

OBJECTIVES

To determine the prevalence of GERD in patients with respiratory disorders and lung involvement; the sensitivity of symptoms in the diagnosis of GERD; and the role of esophageal function tests (manometry and 24- hour pH monitoring) in the diagnosis and treatment of these patients.

METHODS

Prospective study based on a database of 44 patients (29 females) with respiratory disorders: 16 patients had idiopathic pulmonary fibrosis, 11 patients had systemic sclerosis associated interstitial lung disease, 2 patients had polymyositis associated interstitial lung disease, 2 patients had Sjögren associated interstitial lung disease, 2 patients had rheumatoid artrithis associated interstitial lung disease, 1 patient had undifferentiated connective tissue diseases associated interstitial lung disease and 10 patients had sarcoidosis. The average forced vital capacity (% predicted) was 64.3%. All patients had esophageal function tests.

RESULTS

Thirty patients (68%) had pathologic reflux (average DeMeester score: 45, normal <14.7). The average number of reflux episodes recorded 20 cm above the lower esophageal sphincter was 24. Sensitivity and specificity of heartburn were 70% and 57%, of regurgitation 43% and 57%, and of dysphagia 33% and 64%. Twelve patients with GERD underwent a laparoscopic fundoplication which was tailored to the manometric profile: three patients in which peristalsis was normal had a total fundoplication (360°) and nine patients in which the peristalsis was absent had a partial anterior fundoplication (180°).

CONCLUSIONS

The results of our study show that: (a) abnormal reflux was present in about 2/3 of patients with respiratory disorders (idiophatic pulmonary fibrosis, connective tissue disorders and sarcoidosis), and it extended to the upper esophagus in most patients; (b) the sensitivity and specificity of reflux symptoms was very low; and (c) esophageal function tests were essential to establish the diagnosis of abnormal reflux, to characterize the esophageal function and guide therapy. Long term follow-up will be necessary to determine if control of reflux alters the natural history of these respiratory disorders.

Systematic review: the relationship between interstitial lung diseases and gastro-oesophageal reflux disease

BACKGROUND  A potential relationship has been suggested between gastro-oesophageal reflux disease (GERD) and interstitial lung diseases (ILDs). AIM  To evaluate whether there is a causal relationship between GERD and different ILDs. METHODS  We conducted a systematic search of literature published between 1980 and 2010. After a review by two independent authors, each study was assigned an evidence-based rating according to a standard scoring system. RESULTS  We identified 319 publications and 22 of them met the entry criteria. Of those, the relationship between GERD and idiopathic pulmonary fibrosis (IPF) was investigated in 14 articles, pulmonary involvement in systemic sclerosis (SSc) in six articles and pulmonary involvement in mixed connective tissue disease (MCTD) in two articles. We found the prevalence of GERD and/or oesophageal dysmotility to be higher in patients with different types of ILD as compared with those without ILD [Evidence B]. Among patients with IPF, 67-76% demonstrated abnormal oesophageal acid exposure off PPI treatment. No relationship was demonstrated between severity of GERD and severity of IPF [Evidence B]. Data are scant on outcomes of antireflux treatment in patients with IPF. There is a correlation between the severity of ILD and the degree of oesophageal motor impairment in patients with SSc and MCTD [Evidence B]. CONCLUSIONS  Based on the currently available data, a causal relationship between GERD and idiopathic pulmonary fibrosis cannot be established. There is scant evidence about antireflux therapy in idiopathic pulmonary fibrosis patients. There may be an association between lung and oesophageal involvement in systemic sclerosis and mixed connective tissue disease, but a causal relationship cannot be established.

Gastroesophageal reflux therapy is associated with longer survival in patients with idiopathic pulmonary fibrosis

RATIONALE

Gastroesophageal reflux (GER) is highly prevalent in patients with idiopathic pulmonary fibrosis (IPF). Chronic microaspiration secondary to GER may play a role in the pathogenesis and natural history of IPF.

OBJECTIVES

To investigate the relationship between GER-related variables and survival time in patients with IPF.

METHODS

Regression analysis was used to investigate the relationship between GER-related variables and survival time in a retrospectively identified cohort of patients with well-characterized IPF from two academic medical centers.

MEASUREMENTS AND MAIN RESULTS

Two hundred four patients were identified for inclusion. GER-related variables were common in this cohort: reported symptoms of GER (34%), a history of GER disease (45%), reported use of GER medications (47%), and Nissen fundoplication (5%). These GER-related variables were significantly associated with longer survival time on unadjusted analysis. After adjustment, the use of GER medications was an independent predictor of longer survival time. In addition, the use of gastroesophageal reflux medications was associated with a lower radiologic fibrosis score. These findings were present regardless of center.

CONCLUSIONS

The reported use of GER medications is associated with decreased radiologic fibrosis and is an independent predictor of longer survival time in patients with IPF. These findings further support the hypothesis that GER and chronic microaspiration may play important roles in the pathobiology of IPF.

Gastroesophageal reflux and idiopathic pulmonary fibrosis: a review

The histological counterpart of idiopathic pulmonary fibrosis is usual interstitial pneumonia, in which areas of fibrosis of various ages are interspersed with normal lung. This pattern could be explained by repeated episodes of lung injury followed by abnormal wound healing responses. The cause of the initiating alveolar epithelial injury is unknown, but postulated mechanisms include immunological, microbial, or chemical injury, including aspirated gastric refluxate. Reflux is promoted by low basal pressure in the lower oesophageal sphincter and frequent relaxations, potentiated by hiatus hernia or oesophageal dysmotility. In susceptible individuals, repeated microaspiration of gastric refluxate may contribute to the pathogenesis of IPF. Microaspiration of nonacid or gaseous refluxate is poorly detected by current tests for gastroesophageal reflux which were developed for investigating oesophageal symptoms. Further studies using pharyngeal pH probes, high-resolution impedance manometry, and measurement of pepsin in the lung should clarify the impact of reflux and microaspiration in the pathogenesis of IPF.

Prevalence of gastroesophageal reflux disease in patients with idiopathic pulmonary fibrosis

OBJECTIVE

To determine the prevalence of gastroesophageal reflux disease (GERD) and to evaluate its clinical presentation, as well as the esophageal function profile in patients with idiopathic pulmonary fibrosis (IPF).

METHODS

In this prospective study, 28 consecutive patients with IPF underwent stationary esophageal manometry, 24-h esophageal pH-metry and pulmonary function tests. All patients also completed a symptom and quality of life in GERD questionnaire.

RESULTS

In the study sample, the prevalence of GERD was 35.7%. The patients were then divided into two groups: GERD+ (abnormal pH-metry; n = 10) and GERD- (normal pH-metry; n = 18). In the GERD+ group, 77.7% of the patients presented at least one typical GERD symptom. The pH-metry results showed that 8 (80%) of the GERD+ group patients had abnormal supine reflux, and that the reflux was exclusively in the supine position in 5 (50%). In the GERD+ and GERD- groups, respectively, 5 (50.0%) and 7 (38.8%) of the patients presented a hypotensive lower esophageal sphincter, 7 (70.0%) and 10 (55.5%), respectively, presenting lower esophageal dysmotility. There were no significant differences between the groups regarding demographic characteristics, pulmonary function, clinical presentation or manometric findings.

CONCLUSIONS

The prevalence of GERD in the patients with IPF was high. However, the clinical and functional characteristics did not differ between the patients with GERD and those without.

Does chronic microaspiration cause idiopathic pulmonary fibrosis?

Idiopathic pulmonary fibrosis is a diffuse fibrotic lung disease of unknown etiology with no effective treatment. Emerging data support a role for chronic microaspiration (ie, subclinical aspiration of small droplets) in the pathogenesis and natural history of idiopathic pulmonary fibrosis. However, the precise relationship between chronic microaspiration and idiopathic pulmonary fibrosis remains unknown. Gastroesophageal reflux, a presumed risk factor for microaspiration, has been strongly associated with idiopathic pulmonary fibrosis with an estimated prevalence of up to 90%. This review aims to describe the relationship between chronic microaspiration and idiopathic pulmonary fibrosis by laying out the clinical and biologic rationale for this relationship and exploring the scientific evidence available. The gaps in our current understanding of the diagnosis of chronic microaspiration and idiopathic pulmonary fibrosis and the ongoing uncertainties in management and treatment will be highlighted. Defining the role of chronic microaspiration in idiopathic pulmonary fibrosis is essential as it has potential clinical, pathobiological, and treatment implications for this deadly disease.

A review of the potential applications and controversies of non-invasive testing for biomarkers of aspiration in the lung transplant population

Despite improvements in one-yr survival following lung transplantation, five-yr survival lags significantly behind the transplantation of other solid organs. The contrast in survival persists despite advancements in anti-rejection regimens, suggesting a non-alloimmune mechanism to chronic lung transplant failure. Notably, markers of aspiration have been demonstrated in bronchoalveolar lavage (BAL) fluid concurrent with bronchiolitis obliterans syndrome (BOS). This recent evidence has underscored gastroesophageal reflux (GER) and its associated aspiration risk as a non-alloimmune mechanism of chronic lung transplant failure. Given the suggested safety and efficacy of laparoscopic anti-reflux procedures in the lung transplant population, identifying those at risk for aspiration is of prime importance, especially concerning the potential for long-term improvements in morbidity and mortality. Conventional diagnostic methods for GER and aspiration, such as pH monitoring and detecting pepsin and bile salts in BAL fluid, have gaps in their effectiveness. Therefore, we review the applications and controversies of a non-invasive method of defining reflux injury in the lung transplant population: the detection of biomarkers of aspiration in the exhaled breath condensate. Only by means of assay standardization and directed collaboration may such a non-invasive method be a realization in lung transplantation.

Gastroesophageal reflux and pulmonary fibrosis in scleroderma: a study using pH-impedance monitoring

RATIONALE

Interstitial lung disease (ILD) in patients with systemic sclerosis (SSc) is associated with increased morbidity and mortality. Gastroesophageal reflux (GER) is considered a contributing factor in the pathogenesis of ILD.

OBJECTIVES

To characterize GER (acid and nonacid) in patients with SSc with and without ILD.

METHODS

Patients with SSc underwent pulmonary high-resolution computer tomography (HRCT) scan and 24-hour impedance-pH monitoring off-proton pump inhibitor therapy. The presence of pulmonary fibrosis was assessed using validated HRCT-scores. Reflux monitoring parameters included number of acid and nonacid reflux episodes, proximal migration of the refluxate, and distal esophageal acid exposure. Unless otherwise specified, data are presented as median (25th-75th percentile).

MEASUREMENTS AND MAIN RESULTS

Forty consecutive patients with SSc (35 female; mean age, 53 yr; range, 24-71; 15 patients with diffuse and 25 with limited SSc) were investigated; 18 (45%) patients with SSc had pulmonary fibrosis (HRCT score >or= 7). Patients with SSc with ILD had higher (P < 0.01) esophageal acid exposure (10.3 [7.5-15] vs. 5.2 [1.5-11]), higher (P < 0.01) number of acid (41 [31-58] vs. 19 [10-23]) and nonacid (25 [20-35] vs. 17 [11-19]) reflux episodes, and higher (P < 0.01) number of reflux episodes reaching the proximal esophagus (42.5 [31-54] vs. 15 [8-22]) compared with patients with SSc with normal HRCT scores. Pulmonary fibrosis scores (HRCT score) correlated well with the number of reflux episodes in the distal (r(2) = 0.637) and proximal (r(2) = 0.644) esophagus.

CONCLUSIONS

Patients with SSc with ILD have more severe reflux (i.e., more reflux episodes and more reflux reaching the proximal esophagus). Whether or not the development of ILD in patients with SSc can be prevented by reflux-reducing treatments needs to be investigated.

Prevalence of gastroesophageal reflux in end-stage lung disease candidates for lung transplant

BACKGROUND

Aspiration secondary to gastroesophageal reflux has been postulated to be a contributing factor in bronchiolitis obliterans after lung transplantation. It is not clear whether gastroesophageal reflux is a preexisting condition or secondary to intraoperative vagal injury or drug-induced prolonged gastric emptying.

METHODS

The prevalence of gastroesophageal reflux was examined in 78 consecutive end-stage lung disease patients assessed for lung transplantation: emphysema, 21; cystic fibrosis, 5; idiopathic pulmonary fibrosis, 26; scleroderma, 10; and miscellaneous diseases, 16. All underwent esophageal manometry. Two-channel esophageal 24-hour pH testing was completed in 76 patients. Gastric emptying studies were conducted in 36 patients.

RESULTS

Typical gastroesophageal reflux symptoms were documented in 63% of patients. The lower esophageal sphincter was hypotensive in 72% of patients, and 33% had esophageal body dysmotility. Prolonged gastric emptying was documented in 44%, and 38% had abnormal pH testing. The overall DeMeester score was above normal in 32% of patients, and 20% had abnormal proximal pH probe readings.

CONCLUSIONS

Gastroesophageal reflux is highly prevalent in end-stage lung disease patients who are candidates for lung transplantation. Further investigation is needed to study the prevalence of gastroesophageal reflux after lung transplantation and its contribution to chronic allograft dysfunction.

The effect of reflux and bile acid aspiration on the lung allograft and its surfactant and innate immunity molecules SP-A and SP-D

Gastro-esophageal reflux and related pulmonary bile acid aspiration were prospectively investigated as possible contributors to postlung transplant bronchiolitis obliterans syndrome (BOS). We also studied the impact of aspiration on pulmonary surfactant collectin proteins SP-A and SP-D and on surfactant phospholipids--all important components of innate immunity in the lung. Proximal and distal esophageal 24-h pH testing and broncho-alveolar lavage fluid (BALF) bile acid assays were performed prospectively at 3-month posttransplant in 50 patients. BALF was also assayed for SP-A, SP-D and phospholipids expressed as ratio to total lipids: phosphatidylcholine; dipalmitoylphosphatidylcholine; phosphatidylglycerol (PG); phosphatidylinositol; sphingomyelin (SM) and lysophosphatidylcholine. Actuarial freedom from BOS was assessed. Freedom from BOS was reduced in patients with abnormal (proximal and/or distal) esophageal pH findings or BALF bile acids (Log-rank Mantel-Cox p < 0.05). Abnormal pH findings were observed in 72% (8 of 11) of patients with bile acids detected within the BALF. BALF with high levels of bile acids also had significantly lower SP-A, SP-D, dipalmitoylphosphatidylcholine; PG and higher SM levels (Mann-Whitney, p < 0.05). Duodeno-gastro-esophageal reflux and consequent aspiration is a risk factor for the development of BOS postlung transplant. Bile acid aspiration is associated with impaired lung allograft innate immunity manifest by reduced surfactant collectins and altered phospholipids.

Idiopathic pulmonary fibrosis: how often is it really idiopathic?

The cause of idiopathic pulmonary fibrosis (IPF) is unknown. The pathology suggests that IPF results from serial lung injury. It has been suggested that gastroesophageal reflux disease (GERD) may relate to the cause or the progression of the disease. The aims of this study were to determine the prevalence of GERD, the clinical presentation of GERD, and the manometric and reflux profiles in patients with end-stage IPF. Between July 2003 and October 2004, 18 patients with IPF on the lung transplant waiting list were referred for evaluation to the Swallowing Center of the University of California San Francisco. On the basis of the results of the pH monitoring test (5 and 20 cm above the lower esophageal sphincter), the patients were divided into two groups: group A, 12 patients (66%), GERD+; group B, 6 patients (34%), GERD-. The incidence of heartburn and regurgitation was similar between GERD+ and GERD- patients; reflux was clinically silent in one third of GERD+ patients. Reflux was associated with a hypotensive lower esophageal sphincter and abnormal esophageal peristalsis, and it was present in the upright and supine position. The reflux often extended into the proximal esophagus. These results show the following: (1) Two thirds of patients with IPF had GERD; (2) symptoms could not distinguish between those with and without GERD; (3) reflux occurred in the presence of a hypotensive lower esophageal sphincter and abnormal esophageal peristalsis; and (4) reflux occurred in the upright and supine positions, and often extended into the proximal esophagus. We conclude that patients with IPF should be screened for GERD, and if GERD is present, a fundoplication should be performed before or shortly after lung transplantation.

Bile acid aspiration and the development of bronchiolitis obliterans after lung transplantation

BACKGROUND

Aspiration of gastroesophageal refluxate may contribute to lung transplant bronchiolitis obliterans syndrome (BOS). We investigated bile acids in bronchoalveolar lavage fluid (BALF) and studied its role in BOS.

MATERIALS AND METHODS

Surveillance pulmonary function tests and BALF were evaluated in 120 lung recipients. BOS-(0p-3) was diagnosed after 6 months' survival. BOS was defined as "early" if diagnosed within 12 months after a transplant. BALF was assayed for differential cell count, bile acids, and interleukins 8 and 15. Bile acids were considered elevated if greater than normal serum levels ( or =8 micromol/L).

RESULTS

Elevated BALF bile acids were measured in 20 (17%) of 120 patients. BOS was diagnosed in 36 (34%) of 107 patients and judged "early" in 21 (57%) of 36. Median BALF bile acid values were 1.6 micromol/L (range, 0-32 micromol/L) in BOS patients and 0.3 micromol/L (range, 0-16 micromol/L) in non-BOS patients ( P = .002); 2.6 micromol/L (range, 0-32 micromol/L) in early BOS patients and 0.8 micromol/L (range, 0-4.6 micromol/L) in late BOS patients, ( P = .02). Bile acids correlated with BALF IL-8 and alveolar neutrophilia (r = 0.3, P = .0004, and r = 0.3, P = .004, respectively), but not with IL-15. Freedom from BOS was significantly shortened in patients with elevated BALF bile acids (Cox-Mantel test, P = .0001).

CONCLUSIONS

Aspiration of duodenogastroesophageal refluxate is prevalent after lung transplantation and is associated with the development of BOS. Elevated BALF bile acids may promote early BOS development via an inflammatory process, possibly mediated by IL-8 and alveolar neutrophilia.

Supra-oesophageal manifestations of gastro-oesophageal reflux disease

Since the early 1960s, many studies have been published that consider the possible relationship between gastro-oesophageal (acid) reflux (GORD) and various other complaints, including dental erosions, ear, nose and throat problems, chronic cough and asthma. Although a high coincidence of GORD and these supra-oesophageal complaints have been noted, there is no consensus on the pathophysiology and management of such complications. In this article we review the literature published between 1966 and 2000 on this subject. We also analyse the available information on the incidence, pathophysiological mechanisms, diagnostic approach and therapeutic options in the various subgroups of disorders.

Asthmatics with gastroesophageal reflux: long term results of a randomized trial of medical and surgical antireflux therapies

OBJECTIVE

In short term studies, asthma symptoms and pulmonary function have been reported to improve during and after medical treatment or surgical correction of gastroesophageal reflux (GER). In this study, we aimed to determine whether prolonged treatment of GER altered the long term natural history of asthma in asthmatics with GER.

METHODS

A total of 62 patients with both GER and asthma entered a randomized study of antireflux treatments for at least 2 yr: 24 controls (antacids as needed); 22 medical (ranitidine 150 mg t.i.d.); and 16 surgical (Nissen fundoplication). Asthma was defined as a previous diagnosis of asthma with discrete attacks of wheezing and 20% reversibility in airway disease. GER was defined as an abnormal ambulatory 24-h esophageal pH test and macroscopic or microscopic evidence of GER disease. Overall clinical status, asthma symptom scores, and pulmonary medication requirements were recorded monthly. Peak expiratory flow rates were recorded up to seven times per day for 1 wk of each month throughout the years. Pulmonary function, esophageal manometry, and endoscopy with biopsy were repeated yearly.

RESULTS

The 62 patients were followed for up to 19.1 yr. In the surgical group, but not in the medical or control groups, there was an immediate and sustained reduction in acute nocturnal exacerbations of wheezing, coughing, and dyspnea. By the end of 2 yr, improvement, marked improvement, or cure in the overall asthma status occurred in 74.9% of the surgical group, 9.1% of the medical group and 4.2% of the control group, whereas the overall status worsened in 47.8% of the control group, 36.4% of the medical group, and 12.5% of the surgical group (p < 0.001, surgical vs medical and control). The mean asthma symptom score of the surgical group improved 43%, compared with less than 10% in the medical and control groups (p = 0.0009). As determined by changes in peak expiratory flow rates, there was no statistically significant difference in pulmonary function during the 2-yr period or during regularly scheduled follow-up. There was no difference in medication requirements among the groups. There was no difference between the groups in overall survival.

CONCLUSION

In patients with both GER and asthma, antireflux surgery (but not medical therapy with ranitidine 150 mg t.i.d.) has minimal effect on pulmonary function, pulmonary medication requirements, or survival, but significantly improves asthma symptoms and overall clinical status.

Interstitial lung disease and gastroesophageal reflux

Gastroesophageal reflux (GER) has been associated with a number of interstitial lung diseases, including systemic sclerosis and idiopathic pulmonary fibrosis. Systemic sclerosis results in both pulmonary and esophageal manifestations, and studies have shown a correlation, but no causal relation, between GER and pulmonary fibrosis in this condition. The role of GER in idiopathic pulmonary fibrosis has recently been studied using esophageal pH monitoring, and the results show high prevalence of GER compared with normal individuals and patients with other interstitial lung diseases of known cause. Aggressive, long-term therapy of GER and evaluation of its effect on pulmonary disease will allow determination of the real influence of GER on idiopathic pulmonary fibrosis. Additional outcomes-based studies and therapeutic trials are needed to clarify the association between GER and interstitial lung diseases.

Esophageal involvement and pulmonary manifestations in systemic sclerosis

OBJECTIVE

To assess whether esophageal manometric motor disturbances are associated with abnormalities consistent with interstitial lung disease (ILD) on both pulmonary function tests (PFT) and high resolution computerized tomography (HRCT) scans in patients with systemic sclerosis (SSc), during initial evaluation and at 2 years followup.

METHODS

Esophageal manometry, PFT, and HRCT scans were performed in 43 consecutive SSc patients. PFT and HRCT scan parameters were compared between patients with severe esophageal motor dysfunction (i.e., aperistalsis and decreased low esophageal sphincter pressure), patients with moderate esophageal motor dysfunction (hypoperistalsis), and patients without esophageal motor dysfunction on manometry.

RESULTS

During initial evaluation of SSc, patients with severe esophageal motor impairment, compared with those with moderate and without esophageal dysmotility, exhibited significantly decreased median values of diffusing capacity for carbon monoxide (DLco) (68% vs. 94% vs. 104%) and exhibited higher prevalence of evidence for ILD on HRCT scan (57% vs. 27% vs. 18%). At 2 years followup of SSc, patients with severe esophageal motor disturbances, compared with those without, had faster deterioration of DLco median values (-16% vs. +1%) and higher frequency of ILD on HRCT scan (70% vs. 25%).

CONCLUSION

Our series underscores a correlation between the degree of esophageal manometric motor disturbances and evidence for ILD on PFT and HRCT scan in SSc patients, suggesting that gastroesophageal reflux (GER) may be one of the contributing factors of ILD in SSc. Our findings further indicate that patients with severe esophageal impairment may require closer followup of lung parameters. In turn, it suggests that aggressive therapy of GER should be initiated in these SSc patients, as it may result in decreased deterioration of pulmonary function.

Gastroesophageal reflux and asthma: are they related?

The relationship between asthma and gastroesophageal reflux (GER) is controversial. This paper reviews the evidence for an association between them, the effect of asthma on GER, and the effects of GER and antireflux therapy on asthma. The association between the two conditions seems firm but studies of the effects of GER on asthma and asthma on GER are contradictory. Critical review suggests that GER affects asthma symptoms but not pulmonary function. Antireflux therapy improves asthma symptoms and reduces medication requirements but does not improve pulmonary function. The paradox of GER causing asthma symptoms but not changing pulmonary function may be explained by its increasing minute ventilation rather than triggering bronchospasm.

Increased prevalence of gastroesophageal reflux in patients with idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal interstitial lung disease (ILD) of unknown etiology. Introduction of acid into the respiratory tree can produce pulmonary fibrosis. Gastroesophageal reflux (GER) has previously been associated with several other respiratory conditions, including pneumonia, bronchitis, and asthma. To investigate prospectively the possible association of GER and IPF, 17 consecutive patients with biopsy-proven IPF and eight control patients with ILD other than IPF underwent dual-channel, ambulatory esophageal pH monitoring. Sixteen of 17 patients with IPF had abnormal distal and/or proximal esophageal acid exposure compared with four of eight control patients (p = 0.02). In the patients with IPF, mean percent distal total (13.6 versus 3.34, p = 0.006), distal upright (12.4 versus 5.1, p = 0.04), distal supine (14.7 versus 0.88, p = 0.02), and proximal supine (7.48 versus 0.24, p = 0.04) esophageal acid exposure times were significantly greater than those in control patients. Only four patients with IPF (25%) with increased acid exposure had typical reflux symptoms such as heartburn or regurgitation. Patients with IPF have a high prevalence of increased esophageal acid exposure, usually without typical GER symptoms. GER in these patients tends to occur at night and extend into the proximal esophagus. Acid reflux may be a contributing factor in the pathogenesis of IPF.

Respiratory symptoms in patients with gastroesophageal reflux disease following medical therapy and following antireflux surgery

BACKGROUND

It is not known whether antireflux surgery is more effective than medical therapy to control respiratory symptoms (RS) in gastroesophageal reflux disease (GERD).

METHODS

In 21 GERD patients with RS, reflux was assessed by endoscopy, manometry, and pH monitoring. Patients had proton pump inhibitor therapy and cisapride for 6 months. After GERD relapsed following withdrawal of medical therapy, 7 patients with normal esophageal peristalsis had a laparoscopic Nissen fundoplication and 14 with impaired peristalsis a Toupet fundoplication. Respiratory symptoms were scored prior to treatment, at 6 months following medical therapy, and at 6 months after surgery.

RESULTS

Heartburn and esophagitis were effectively treated by medical and surgical therapy. Only surgery improved regurgitation. Respiratory symptoms improved in 18 patients (85.7%) following surgery and in only 3 patients (14.3%) following medical therapy (P <0.05). Esophageal peristalsis improved following the Toupet fundoplication.

CONCLUSION

Medical therapy fails to control reflux since it does not inhibit regurgitation. Surgery controls reflux and improves esophageal peristalsis, which contributes to its superiority over medical therapy in the treatment of RS associated with GERD.

Gastric asthma? No change in respiratory impedance during intraesophageal acidification in adult asthmatics

BACKGROUND

In patients with asthma, gastroesophageal reflux (GER) has been shown to be a common finding, and a number of investigators have suggested that reflux may have a deleterious effect in asthma, either as a result of recurrent (micro)aspiration or by some form of a reflex mechanism.

AIM OF THE STUDY

To measure changes in lung function in response to intraesophageal acid perfusion in asthmatics with GER.

METHODS

In 12 patients with bronchial asthma and complaints suggesting GER with increased reflux scores during 24-h intraesophageal pH monitoring, impedance measurements of the respiratory system using the technique of forced oscillations and spirometry were performed after intraesophageal acidification.

RESULTS

No statistically significant changes in FEV1 or in respiratory impedance were demonstrated after intraesophageal acid provocation.

CONCLUSION

No direct effect of intraesophageal acidification on bronchomotor tone was demonstrated in asthmatics with GER.

Coexisting endogenous lipoid pneumonia, cholesterol granulomas, and pulmonary alveolar proteinosis in a pediatric population: a clinical, radiographic, and pathologic correlation

Benign pulmonary diseases that have been associated with the accumulation of endogenous lipids within the alveoli, bronchioles, and interstitial tissues include endogenous lipoid pneumonia (ELP), pulmonary alveolar proteinosis (PAP), pulmonary interstitial and intra-alveolar cholesterol granulomas (PICG), various xanthomatous lesions, and malakoplakia. In ELP, fat-filled finely vacuolated macrophages fill the alveoli. In PAP, the aveoli become filled with cholesterol and periodic acid-Schiff (PAS)-positive acellular debris. In PICG, cholesterol esters are released from degenerating macrophages and, as organization occurs, the cholesterol is deposited in the form of acicular clefts within the interstitium. These morphologically distinct presentations of endogenous lipid deposition within the lung have long been thought to represent unique disease processes but several authors now postulate a possible relationship between these entities. We report here on the clinical, radiographic, and morphologic findings in eight pediatric patients with diverse primary disease processes who were subsequently found to have varying and often coexisting degrees of ELP, PAP, and PICG.

Gastro-oesophageal reflux and severity of pulmonary disease in cystic fibrosis

The correlation between oesophageal dysfunction (OD), pathologic gastro-oesophageal reflux (GOR), and severity of pulmonary disease was studied in 12 patients with cystic fibrosis (CF). They were interviewed about symptoms of OD and underwent 24-h pH recording in the oesophagus, oesophageal manometry combined with reflux provocation tests, the acid perfusion test, the acid clearance test, lung function tests, and scoring of the chest radiograph. Six of the 12 patients reported symptoms of OD. Abnormal GOR, as shown by 24-h pH monitoring of the oesophagus, was found in eight of them. Altogether 9 of the 12 participants had at least one pathologic oesophagus test result. Results of radiologic examinations of the oesophagus, performed in six patients, were pathologic. The four patients with the best chest radiograph scores and the best lung function had significantly less signs and symptoms of OD and GOR than the other eight patients. We conclude that OD, GOR, and pulmonary disease covariate in CF.

The otolaryngologic manifestations of gastroesophageal reflux disease (GERD): a clinical investigation of 225 patients using ambulatory 24-hour pH monitoring and an experimental investigation of the role of acid and pepsin in the development of laryngeal injury

Occult (silent) gastroesophageal reflux disease (GER, GERD) is believed to be an important etiologic factor in the development of many inflammatory and neoplastic disorders of the upper aerodigestive tract. In order ot test this hypothesis, a human study and an animal study were performed. The human study consisted primarily of applying a new diagnostic technique (double-probe pH monitoring) to a population of otolaryngology patients with GERD to determine the incidence of overt and occult GERD. The animal study consisted of experiments to evaluate the potential damaging effects of intermittent GER on the larynx. Two hundred twenty-five consecutive patients with otolaryngologic disorders having suspected GERD evaluated from 1985 through 1988 are reported. Ambulatory 24-hour intraesophageal pH monitoring was performed in 197; of those, 81% underwent double-probe pH monitoring, with the second pH probe being placed in the hypopharynx at the laryngeal inlet. Seventy percent of the patients also underwent barium esophagography with videofluoroscopy. The patient population was divided into seven diagnostic subgroups: carcinoma of the larynx (n = 31), laryngeal and tracheal stenosis (n = 33), reflux laryngitis (n = 61), globus pharyngeus (n = 27), dysphagia (n = 25), chronic cough (n = 30), and a group with miscellaneous disorders (n = 18). The most common symptoms were hoarseness (71%), cough (51%), globus (47%), and throat clearing (42%). Only 43% of the patients had gastrointestinal symptoms (heartburn or acid regurgitation). Thus, by traditional symptomatology, GER was occult or silent in the majority of the study population. Twenty-eight patients (12%) refused or could not tolerate pH monitoring. Of the patients undergoing diagnostic pH monitoring, 62% had abnormal esophageal pH studies, and 30% demonstrated reflux into the pharynx. The results of diagnostic pH monitoring for each of the subgroups were as follows (percentage with abnormal studies): carcinoma (71%), stenosis (78%), reflux laryngitis (60%), globus (58%), dysphagia (45%), chronic cough (52%), and miscellaneous (13%). The highest yield of abnormal pharyngeal reflux was in the carcinoma group and the stenosis group (58% and 56%, respectively). By comparison, the diagnostic barium esophagogram with videofluoroscopy was frequently negative. The results were as follows: esophagitis (18%), reflux (9%), esophageal dysmotility (12%), and stricture (3%). All of the study patients were treated with antireflux therapy. Follow-up was available on 68% of the patients and the mean follow-up period was 11.6 +/- 12.7 months.(ABSTRACT TRUNCATED AT 400 WORDS)

Chronic respiratory symptoms and occult gastroesophageal reflux. A prospective clinical study and results of surgical therapy

Seventy-seven patients with a primary complaint of persistent cough, wheezing, and/or recurrent pneumonia were evaluated for the presence of occult gastroesophageal reflux disease. Fifty-four patients (70%) had increased esophageal acid exposure on 24-hour pH monitoring of the distal esophagus. In 28% of these patients the respiratory symptoms were thought to be due to aspiration because they occurred during or within 3 minutes after a reflux episode. In the other patients, the respiratory symptoms were either induced by or were unrelated to reflux episodes. The number of respiratory symptoms reported by the patients with increased esophageal acid exposure was directly related to the presence of a nonspecific esophageal motility abnormality (p less than 0.05). This suggested that a motility disorder contributes to aspiration by promoting the aboral flow of refluxed gastric juice. Seventeen patients with increased esophageal acid exposure had an antireflux operation to relieve their respiratory complaints. Patients whose respiratory symptoms induced reflux episodes were not helped by the procedure. Of the other patients, symptoms were abolished by the procedure only in those with normal esophageal motility. It is concluded that the majority of patients suffering from chronic unexplained respiratory symptoms have occult gastroesophageal reflux disease, but only a minority of them are helped by surgery. Carefully performed esophageal function studies are needed to select those patients who will benefit from a surgical antireflux procedure.

Long-term evaluation of esophageal and pulmonary function in patients with repaired esophageal atresia and tracheoesophageal fistula

Patients who have undergone repair of esophageal atresia and tracehoesophageal fistula as infants have been noted to have residual esophageal dysmotility and pulmonary dysfunction during their childhood years. However, limited information is available about the long-term follow-up of these patients. In this study we performed esophageal and pulmonary function studies on 12 adults who had required surgical repair of these defects in the first week of life. Most patients had symptoms of dysphagia and heartburn at time of evaluation. Pathologic gastroesophageal reflux was documented in 67% of patients and esophagitis was noted in 34%. All patients had esophageal motility abnormalities characterized by low-amplitude nonperistaltic waves throughout most of the esophagus. In addition, although most patients had no respiratory symptoms, mild restrictive lung volumes were noted in many patients. However, airflow obstruction and airway hyperreactivity were not present. These data demonstrate that clinical symptoms and abnormal esophageal manometry and pulmonary function persist well into the third and beginning of the fourth decade after repair of esophageal atresia and tracheoesophageal fistula in infancy.

Pulmonary function in older children and young adults with gastroesophageal reflux

A wide variety of types of pulmonary diseases and respiratory symptoms have been associated with gastroesophageal reflux (GER). Asthma, chronic bronchitis, bronchiectasis, and pulmonary fibrosis have all been linked to GER, but causal mechanisms have been difficult to establish. To characterize pulmonary function abnormalities in older children and young adults (age 7-23 years) with GER, lung function was evaluated in 22 patients being treated for reflux. The patients were divided into two groups: nine subjects (Group 1) had no history of pulmonary symptoms. Thirteen subjects (Group 2) had known pulmonary disease; all had diagnosed asthma, and five had a history of recurrent pneumonia. Lung volumes and spirometry were measured. Airway reactivity was assessed by measuring change in flows following isocapneic hyperventilation of subfreezing air. The presence of "small airway" disease was assessed by air-helium flow volume curves and the single breath oxygen test. Lung size, as indicated by measurement of total lung capacity, was normal in all patients. Flow rates, density dependence of maximal expiratory flow, single breath oxygen test, and tests of airway reactivity were abnormal only in Group 2 patients and were normal in the Group 1 patients. That not all children with GER have abnormal pulmonary function suggests that, if there is a causal relationship between GER and lung disease, it is multi-factorial in nature. Children with GER who do have lung disease have evidence of airway obstruction, maldistribution of ventilation, and increased airway reactivity, but do not have restricted lung volumes.

Pulmonary complications of benign esophageal disease

Three patients with esophageal reflux and associated pulmonary complications are presented: one with a lung abscess, another with recurring pneumonitis that required hospitalization, and the third with bronchospasm or asthma secondary to reflux and chronic aspiration. Two were treated surgically by the repair of esophageal and pulmonary lesions. The third patient was treated medically, with resolution of pulmonary symptoms and improvement of pulmonary function. A review is presented of the association between esophageal and pulmonary problems and of the insidious complications that may result.