Interstitial lung disease and gastroesophageal reflux

Association between Antacid Exposure and Risk of Interstitial Lung Diseases

BACKGROUND

The mechanisms leading to lung fibrosis are still under investigation. This study aimed to demonstrate whether antacids could prevent the development of interstitial lung disease (ILD).

METHODS

This population-based longitudinal cohort study was conducted between January 2006 and December 2010 in South Korea. Eligible subjects were ≥40 years of age, exposed to proton pump inhibitors (PPI)±histamine-2 receptor antagonists (H-2 blockers) or H-2 blockers only, and had no history of ILD between 2004 and 2005. Exposure to antacids was defined as the administration of either PPI or H-2 receptor antagonists for >14 days, whereas underexposure was defined as antacid treatment administered for less than 14 days. Newly developed ILDs, including idiopathic pulmonary fibrosis (IPF), were counted during the 5-year observation period. The association between antacid exposure and ILD development was evaluated using adjusted Cox regression models with variables, such as age, sex, smoking history, and comorbidities.

RESULTS

The incidence rates of ILD with/without antacid use were 43.2 and 33.8/100,000 person-years, respectively and those of IPF were 14.9 and 22.9/100,000 person-years, respectively. In multivariable analysis, exposure to antacid before the diagnosis of ILD was independently associated with a reduced development of ILD (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.45 to 0.71; p<0.001), while antacid exposure was not associated with development of IPF (HR, 0.88; 95% CI, 0.72 to 1.09; p=0.06).

CONCLUSION

Antacid exposure may be independently associated with a decreased risk of ILD development.

Relationship Between Esophageal Disease and Pulmonary Fibrosis

Esophageal disorders are prevalent among patients with chronic lung diseases, including idiopathic pulmonary fibrosis (IPF). Gastroesophageal reflux disease (GERD) has been associated with IPF prevalence, severity, and respiratory decline. The pathophysiologic relationship between GERD and IPF is likely bidirectional, with aspiration of refluxate leading to lung inflammation and fibrosis, while the restrictive pulmonary physiology may contribute to altered transdiaphragmatic pressure gradient and increased reflux. Esophageal symptoms are frequently absent and do not predict esophageal dysfunction or pathologic reflux in patients with IPF, and objective diagnostic tools including upper endoscopy, ambulatory reflux monitoring, and high-resolution manometry are often needed. Impedance-based testing that identifies both weakly/non-acidic and acid reflux may provide important additional diagnostic value beyond pH-based acid testing alone. Novel metrics and maneuvers, including advanced impedance measures on impedance-pH study and provocative testing on HRM, may hold promise to future diagnostic advancements. The main treatment options include medical therapy with acid suppressants and anti-reflux surgery, although their potential benefits in pulmonary outcomes of IPF require further validations. Future directions of research include identifying phenotypes of IPF patients who may benefit from esophageal testing and treatment, determining the optimal testing strategy and protocol, and prospectively assessing the value of different esophageal therapies to improve outcomes while minimizing risks. This review will discuss the pathophysiology, evaluation, and management of esophageal diseases, particularly GERD, in patients with IPF, as informed by the most recent publications in the field, in hopes of identifying targets for future study and research.

Pulmonary manifestations of gastroesophageal reflux disease

INTRODUCTION

Gastroesophageal reflux disease (GERD) is a widespread condition with a significant impact on the quality of life and healthcare resources. In addition to its gastrointestinal problems, GERD has been linked to a variety of respiratory diseases either as a direct cause, or as a risk factor to the inability to control or worsening of the disease.

AREAS COVERED

We performed a literature search in the PubMed database for articles addressing GERD and pulmonary diseases. This review will discuss several different pulmonary diseases affected by GERD ranging from upper airway including chronic cough, vocal cord dysfunction, lower airway diseases including COPD, asthma, and bronchiolitis obliterans syndrome to parenchymal diseases such as interstitial lung diseases. The review will discuss several different pulmonary manifestations of GERD and their contribution to patient mortality and morbidity. It will also review the mechanisms leading to these diseases, diagnostic workup, and the role of the available treatment options.

EXPERT OPINION

GERD is often overlooked as a cause of respiratory symptoms and illnesses. The literature is sparse on the relation between GERD and respiratory diseases such as interstitial lung diseases and bronchiolitis obliterans including its role in pathogenesis, mechanisms of lung injury, and whether treatment of GERD is effective in managing such illnesses.

Clinical outcomes of laryngopharyngeal reflux treatment: A systematic review and meta-analysis

OBJECTIVES

To investigate the therapeutic benefit of proton pump inhibitors (PPIs) over placebo in patients with laryngopharyngeal reflux (LPR) and to analyze the epidemiological factors of heterogeneity in the literature.

METHODS

An electronic literature search was conducted to identify articles published between 1990 and 2018 about clinical trials describing the efficiency of medical treatment(s) on LPR. First, a meta-analysis of placebo randomized controlled trials (RCTs) comparing PPIs versus placebo was conducted according to diet. The heterogeneity, response to PPIs, and evolution of clinical scores were analyzed for aggregate results. Second, a systematic review of diagnosis methods, clinical outcome of treatment, and therapeutic regimens was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

RESULTS

The search identified 1,140 relevant publications, of which 72 studies met the inclusion criteria for a total of 5,781 patients. Ten RCTs were included in the meta-analysis. The combined relative risk was 1.31 in favor of PPIs and increased to 1.42 when patients did not receive diet recommendations. Randomized controlled trials were characterized by a significant heterogeneity due to discrepancies in clinical therapeutic outcomes, diagnosis methods (lack of gold standard diagnostic tools), and therapeutic scheme. The epidemiological analysis of all articles supports the existence of these discrepancies in the entire literature. In particular, many symptoms and signs commonly encountered in LPR are not assessed in the treatment effectiveness. The lack of diagnosis precision and variability of inclusion criteria particularly create bias in all reported and included articles.

CONCLUSION

This meta-analysis supports a mild superiority of PPIs over placebo and the importance of diet as additional treatment but demonstrates the heterogeneity between studies, limiting the elaboration of clear conclusions. International recommendations are proposed for the development of future trials. Laryngoscope, 129:1174-1187, 2019.

Computed Tomography of the Esophagus in Scleroderma and Lung Disease

Systemic sclerosis, or scleroderma, is a collagen vascular disease characterized by hardening of the skin and involvement of internal organs, most commonly the esophagus. The most frequent cause of death in these patients is lung disease. Esophageal dysfunction has been implicated in the pathogenesis of interstitial lung disease. We previously developed a standard for the esophageal diameter on chest computed tomography (CT) and hypothesized that patients with esophageal dilation would be more likely to have interstitial lung disease than those without. In this study, we test this in 121 systemic sclerosis patients with interstitial lung disease and 48 of those without interstitial lung disease. For controls, we evaluated 121 patients followed at a general pulmonary clinic and the previously studied normal healthy standards. This study demonstrated that esophageal dilation is common in systemic sclerosis patients (66.3% for the maximal esophageal diameter more than or equal to 15 mm), that systemic sclerosis patients with interstitial lung disease have more dilated esophagi than those without interstitial lung disease (median 19.4 mm vs. 14.1 mm), and that esophageal parameters are negatively correlated with pulmonary function. We also found that patients from general pulmonary clinic were more likely to have dilated esophagi than normal controls (median 12.1 mm vs. 9.7 mm). The CT measurement of esophageal diameter may be a useful marker of patients at risk for developing lung disease.

Association of gastroesophageal factors and worsening of forced vital capacity in systemic sclerosis

OBJECTIVE

Interstitial lung disease (ILD) is a common complication of systemic sclerosis (SSc) and causes death. Once lung fibrosis occurs, disease course may become stable or decline. Little is known about risks for progression. We studied SSc-gastroesophageal (GE) involvement in relation to worsening forced vital capacity (FVC) on pulmonary function tests (PFT) to investigate whether it was related to progression. Our objective was to determine whether GE reflux and dysphagia are associated with progressive moderate/severe ILD as measured by PFT over 3 years.

METHODS

The Canadian Scleroderma Research Group is a multicenter SSc database that collects data annually. Using indicators of GE involvement and annual PFT, comparisons were made between no/mild ILD, stable moderate/severe ILD, and progressive moderate/severe ILD groups based on changes of FVC. Multivariate analyses determined associations between GE factors and ILD development and progression.

RESULTS

There were 1043 patients with SSc (mean age 55.7 yrs, mean disease duration 10.8 yrs); one-quarter had pulmonary fibrosis on chest radiograph that was related to FVC percentage predicted (Spearman's rho -0.39; p < 0.01). Physician indicators such as esophageal dysmotility (p = 0.009) and postesophageal dilatation (p = 0.041), and patient indicators such as difficulty swallowing (p = 0.016) and waking up choking (p = 0.026) were associated with low FVC. In comparing progressive and stable moderate/severe FVC (< 70% predicted), early satiety (p = 0.018) and a combination term of postdilatation and choking (p = 0.042) increased risk of progression of ILD. Topoisomerase I was not associated with progression over followup.

CONCLUSION

Symptoms of esophageal dysmotility were associated with worsening FVC in SSc, especially if both need for esophageal dilatation and choking were present.

Reflux esophagitis increased the risk of bladder pain syndrome/interstitial cystitis: a 3-year follow-up study

AIMS

Reflux esophagitis (RE) is a common disease which has been recognized to be associated with several medical co-morbidities. However, the association between RE and bladder pain syndrome/interstitial cystitis (BPS/IC) is still unknown. The present study aimed to explore the association between these two diseases.

METHODS

We identified 8,962 female patients who had received a diagnosis of RE as the study cohort. We randomly selected 44,810 subjects to be included as the comparison cohort. Each patient in this study was individually tracked for a 3-year period to identify those who subsequently received a diagnosis of BPS/IC. Cox proportional hazards regressions were carried out to estimate the 3-year risk of BPS/IC following a diagnosis of RE.

RESULTS

The incidence of BPS/IC following a diagnosis of RE was 4.3% during the follow-up period for all subjects. The incidence rate of BPS/IC was 2.38 [95% confidence interval (CI): 2.21-2.57] per 100 person-years in patients with RE, and 1.24 (95% CI: 1.18-1.30) per 100 person-years in controls. Cox proportional analysis indicated that the hazard ratio (HR) of BPS/IC for patients with RE was 2.00 (95% CI = 1.82-2.20, P < 0.001) that of controls. The adjusted HR of BPS/IC for patients with RE was 1.40 (95% CI = 1.27-1.55, P < 0.001) after taking age group, urbanization level, and medical comorbidity into consideration.

CONCLUSION

We found that patients with RE were at a higher risk than with comparison patients for having been subsequently diagnosed with BPS/IC during longitudinal follow-up.

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.

Scleroderma lung disease

Pulmonary involvement is second in frequency only to esophageal involvement as a visceral complication of systemic sclerosis (SSc) and has surpassed renal involvement as the most common cause of death. Interstitial lung disease and pulmonary vascular disease, particularly pulmonary arterial hypertension, are the most commonly encountered types of lung involvement. Chronic aspiration, airway disease, neuromuscular weakness, extrinsic pulmonary restrictive pathology, pleural effusions, pneumothorax, and lung cancer cause clinically significant disease and occur commonly enough to be routinely considered in the assessment of the SSc patient with respiratory symptoms. Affected patients have a significantly worse prognosis than patients with SSc who are free of pulmonary involvement.

Lung involvement in systemic sclerosis

Scleroderma is a multisystem disease characterized by a severe inflammatory process and exuberant fibrosis. Lung involvement is a frequent complication and a leading cause of morbidity and mortality in this syndrome. Two major pulmonary syndromes are associated with scleroderma; a pulmonary vascular disorder evolving over time into relatively isolated pulmonary arterial hypertension (PAH), and interstitial lung disease (ILD). Each syndrome, when present, is a cause of morbidity and significantly reduces survival of scleroderma patients when compared to patients free of lung complication. When pulmonary hypertension and ILD are combined, survival is further reduced. Current therapy appears to have no meaningful effect on either condition and, thus, there is a need for better understanding of underlying pathogenic mechanisms. This review focuses on clinical, diagnostic, and therapeutic features of PAH and ILD as well as other frequent but less debilitating lung complications of scleroderma.

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.

The differential effect of gastroesophageal reflux disease on mechanostimulation and chemostimulation of the laryngopharynx

OBJECTIVES

Laryngo-hypopharyngeal sensitivity (LPS) as measured by thresholds to mechanostimulation and chemostimulation is important in the prevention of pulmonary aspiration. The presence of gastroesophageal reflux disease (GERD) increases thresholds to mechanostimulation. However, the effect of GERD on thresholds to chemostimulation remains unknown. The aim of this study was to compare laryngo-hypopharyngeal thresholds to chemostimulation in subjects with GERD with those of healthy subjects and to determine the relationship between thresholds to mechanostimulation and chemostimulation.

METHODS

Forty-eight patients with GERD and 18 control subjects without GERD underwent LPS testing using the Fiberoptic Endoscopic Evaluation of Swallowing with Sensory Testing technique. All 48 patients and 10 of the control subjects also underwent threshold testing for chemostimulation via hypopharyngeal infusions of normal saline and 0.1 N hydrochloric acid performed in a randomized, blinded manner. Thresholds to mechanical stimulation, as measured by the lowest air pressure level required to elicit the laryngeal adductor reflex (LAR), were determined before and after laryngo-hypopharyngeal infusions. Thresholds to chemical stimulation were measured by determining the infusion volume of acid or saline required to trigger an airway protection response.

RESULTS

The mean LAR threshold of the patient group was significantly higher compared with that of control subjects (9.5 mm Hg vs 3.9 mm Hg, P < .01). Compared with control subjects, significantly less acid (0.13 mL vs 0.21 mL, P < .01) was required to trigger airway protective responses in GERD subjects. There is a strong negative correlation between the volume of acid infused and the LAR thresholds in the control subjects (r = -0.69, P < .05).

CONCLUSIONS

Compared with the control subjects, subjects with GERD have significantly increased thresholds to mechanical stimulation, suggesting reduced mechanosensitivity, but significantly reduced thresholds to chemical stimulation, suggesting heightened chemosensitivity. There is an inverse relationship between mechanosensitivity and chemosensitivity. This relationship may be integral in maintaining airway protection.

[Boundaries of the lung - Relationship to the gastrointestinal system]

The relation between the respiratory and gastrointestinal systems has been long recognized and depends on various anatomical, physiological and pathological mechanisms. The certain recognition of some interactions, such as the relation between asthma and gastroesophageal reflux, is more or less intuitive to the pulmonogist, whereas other areas of confluence are more easily missed, such as the relation between airway disorders and inflammatory bowel disease. The purpose of this article is to review the interaction between the lung and the gastrointestinal systems, as far as anatomy, physiology, pathology, clinical manifestations and therapeutical options go.

Pulmonary manifestations of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) may cause, trigger or exacerbate many pulmonary diseases. The physiological link between GERD and pulmonary disease has been extensively studied in chronic cough and asthma. A primary care physician often encounters patients with extra esophageal manifestations of GERD in the absence of heartburn. Patients may present with symptoms involving the pulmonary system; noncardiac chest pain; and ear, nose and throat disorders. Local irritation in the esophagus can cause symptoms that vary from indigestion, like chest discomfort and abdominal pain, to coughing and wheezing. If the gastric acid reaches the back of the throat, it may cause a bitter taste in the mouth and/or aspiration of the gastric acid into the lungs. The acid can cause throat irritation, postnasal drip and hoarseness, as well as recurrent cough, chest congestion and lung inflammation leading to asthma and/or bronchitis/ pneumonia. This clinical review examines the potential pathophysiological mechanisms of pulmonary manifestations of GERD. It also reviews relevant clinical information concerning GERD-related chronic cough and asthma. Finally, a potential management strategy for GERD in pulmonary patients is discussed.

[Systemic sclerosis and the gastrointestinal tract. Diagnostic and therapeutic approach]

In systemic sclerosis esophagus is affected in 90% followed by anal and rectal involvement (50-70%), stomach (40-70%), colon (10-50%) and small bowel (40%). The main clinical findings are esophagic: dysphagia and sign of gastroesophageal reflux and its complications. Gastric symptomatology is a consequence of gastroparesis (postprandial fullness, nausea). Intestinal affection produces hypomotility (abdominal distention, deficient intestinal absorption, bacterial overgrowth). In colon there are diverticula, intestinal constipation, and fecal incontinence. For the diagnosis of GIT involvement the following are useful: studies of digestive tract with contrast media, endoscopy of upper GIT; gastric emptying; pH metry; esophageal and rectal manometry, as well as test to investigate deficient intestinal absorption syndrome. The prokinetic are a cornerstone for the treatment of hypomotility of GIT, along with pump proton inhibitors for the esophageal alteration and antibiotics for bacterial overgrowth.

Review article: respiratory manifestations of gastro-oesophageal reflux disease

BACKGROUND

Respiratory manifestations represent one of the most prevalent and difficult-to-manage extra-oesophageal syndromes of gastro-oesophageal reflux disease.

AIMS

To review the epidemiology, pathophysiological mechanisms and therapeutic outcomes of reflux-related respiratory disorders.

METHODS

Search of the literature published in English using PubMed database.

RESULTS

There is a discrepancy between the high prevalence of reflux in asthmatics and the limited efficacy of antireflux therapies. Asthma per se may cause reflux. Patients with difficult-to-treat asthma and/or nocturnal symptoms should be screened for reflux. Reflux can induce chronic cough through different mechanisms including micro-aspiration and both local and central reflexes. Cough and reflux may precipitate each other. A meta-analysis found no significant difference between placebo and proton pump inhibitors in the resolution of cough. Encouraging results have been reported, following antireflux surgery in patients selected on the basis of pH-impedance monitoring. Attention has been drawn to obstructive sleep apnoea syndrome.

CONCLUSIONS

The role of gastro-oesophageal reflux disease in the pathogenesis of miscellaneous respiratory disorders has been discussed for decades and established in asthma and cough. However, no major therapeutic advances have been reported recently. Future trials should concentrate on patient selection and the control of efficacy using recently developed technologies, such as pH-impedance monitoring.

Esophageal involvement in scleroderma: gastroesophageal reflux, the common problem

OBJECTIVES

Systemic sclerosis (SSc) is a multisystem disease characterized by abnormalities of small blood vessels, and fibrosis of the skin and internal organs including gastrointestinal tract. This article reviews the esophageal involvement in SSc, emphasizing the gastroesophageal reflux, which is a common problem in SSc patients.

METHODS

We conducted a Medline search from 1966 to 2005. The keywords "systemic sclerosis," "esophageal involvement," "gastroesophageal reflux," "esophagitis," and "treatment" were used.

RESULTS

The gastrointestinal tract is frequently affected in diffuse and limited disease. Although any part of the gastrointestinal tract can be involved, esophageal disease occurs in nearly all patients with SSc. Common esophageal manifestations in SSc include motility abnormalities and gastroesophageal reflux (GER), Barrett's esophagus, adenocarcinoma, infectious esophagitis, and drug-induced esophagitis. Common complications of GER include esophagitis with erosions and bleeding and stricture formation. Extraesophageal manifestations of GER include mouth ulcers, chronic cough, hoarse voice, sore throat, pharyngitis, laryngospasm, asthma, and recurrent pneumonia. Diagnostic procedures used in the investigation of esophageal involvement include barium esophagram, esophageal manometry, 24-hour ambulatory pH, and endoscopy. Treatment of GER in SSc includes behavioral modification and medical therapy, mainly with proton pump inhibitors. Surgical intervention has a limited role in the management of GER in selected SSc patients.

CONCLUSIONS

Esophageal involvement is frequent in SSc patients. Gastroesophageal reflux may cause high morbidity. Careful examination of the patients reveals gastrointestinal abnormalities even in patients without symptoms. Appropriate treatment of esophageal involvement ameliorates symptoms and prevents complications.

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.

Sole treatment of acid gastroesophageal reflux in idiopathic pulmonary fibrosis: a case series

RATIONALE

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease despite the available treatment regimes. Increased acid gastroesophageal reflux (GER) occurs in IPF patients.

OBJECTIVES

To follow the course of IPF in patients while being treated for acid GER alone.

METHODS

A retrospective review of the clinical outcomes of four patients with newly diagnosed IPF and increased acid GER who chose to be treated solely with anti-acid GER therapy were followed up regularly with pulmonary function tests (PFTs) [measuring FVC and the diffusing capacity of the lung for carbon monoxide] over a period of 2 to 6 years. Anti-acid GER therapy was administered using proton-pump inhibitors and fundoplication, if needed. Adequate suppression of acid GER was ascertained by 24-h esophageal pH monitoring.

MAIN RESULTS

PFT results in all four patients stabilized or improved while their conditions were maintained with adequate treatment for acid GER. All patients were alive at the last follow-up, and none manifested an acute exacerbation of IPF or needed treatment for respiratory problems during this period. After maintaining 4 years of improved status (based on PFT and exercise testing findings) while adhering to treatment for acid GER, one patient's deterioration correlated with poor compliance to daily treatment during the fifth year, although the PFT results at the sixth year showed stabilization compared to baseline values. The condition of another patient was stabilized by adhering to anti-acid GER treatment after an initial period of deterioration that was associated with nonadherence

CONCLUSIONS

Future clinical studies are indicated to clarify the role of acid GER in IPF and to determine whether adequate treatment for increased acid GER in part improves the outcome of patients with IPF.

Laparoscopic fundoplication in patients with end-stage lung disease awaiting transplantation

OBJECTIVE

There is a strong association between reflux and end-stage lung disease, especially idiopathic pulmonary fibrosis. The presence of reflux after lung transplantation might predispose to the development of bronchiolitis obliterans. We evaluated the risk and physiologic effect of laparoscopic fundoplication in patients on the lung transplant waiting list.

METHODS

One hundred forty-nine patients on the lung transplant waiting list between March 2001 and January 2005 were evaluated. Nineteen were found to have a history of reflux, continued symptoms, and severe reflux by means of pH and manometric studies and underwent laparoscopic fundoplication. The postoperative course of these 19 patients, including lung function, was retrospectively reviewed. Postoperatively, the lung function of the 14 patients with idiopathic pulmonary fibrosis who underwent the laparoscopic Nissen procedure was compared with that of 31 patients with idiopathic pulmonary fibrosis on the transplant waiting list who did not undergo fundoplication.

RESULTS

There were no perioperative complications and no decrease in lung function over the 15-month average follow-up. Exercise capacity remained stable, as determined on the basis of 6-minute walk distance. Patients with idiopathic pulmonary fibrosis treated with fundoplication had stable oxygen requirements, whereas control patients with idiopathic pulmonary fibrosis on the waiting list had a statistically significant deterioration in oxygen requirement.

CONCLUSIONS

Laparoscopic fundoplication can be performed safely in patients with end-stage lung disease awaiting lung transplantation. Overall, these patients maintained stable lung function during the follow-up period. When compared with a control group of patients with idiopathic pulmonary fibrosis not undergoing fundoplication, there was stabilization of oxygen requirement. A larger prospective trial evaluating the effect of laparoscopic fundoplication on underlying lung function in this patient population is warranted.

Lipid-laden alveolar macrophage index in sputum is not useful in the differential diagnosis of pulmonary symptoms secondary to gastroesophageal reflux

BACKGROUND

Gastroesophageal reflux (GER) is frequently associated with pulmonary diseases. Esophageal acid-induced bronchoconstriction and recurrent microaspirations of gastric content are the proposed mechanisms. At present there is not a sensitive test available to prove a causal relationship between pulmonary symptoms and GER. In this study we aimed to investigate the value of a marker of aspiration: lipid-laden alveolar macrophage index (LLAM) in induced sputum, in the diagnosis of pulmonary symptoms highly suspected to be due to GER.

METHODS

Twenty-two patients with the endoscopic diagnosis of erosive esophagitis who had various pulmonary symptoms that could not be attributed to any apparent etiology constituted the study group. Fifteen healthy volunteers with no prior diagnosis of gastroesophageal and lung disease constituted the control group. Subjects were questioned for pulmonary and abdominal symptoms and underwent physical examination, chest radiography, pulmonary function tests, and sputum induction. Prepared cytospins were stained with oil red-O to detect cytoplasmic lipid droplets and LLAM index was calculated.

RESULTS

There was no statistically significant difference between the LLAM indexes of the study (1.9 +/- 3.3) and control group (4.2 +/- 4.5). LLAM index had a significant positive correlation with the duration of reflux symptoms (p=0.01, r=0.5).

CONCLUSIONS

LLAM index is not found to be a valuable method in the differential diagnosis of pulmonary symptoms suspected to be due to GER.

Clinical aspects of lung involvement: lessons from idiopathic pulmonary fibrosis and the scleroderma lung study

Interstitial lung disease (ILD) occurs frequently among patients with systemic slcerosis (SSc) and accounts for significant morbidity and mortality. SSc-ILD resembles idiopathic pulmonary fibrosis (IPF) in many respects; each is characterized by a restrictive ventilatory defect that results from an active fibrosing process in the lung interstitium, and each is characterized by ground glass opacification on high resolution computed tomography (HRCT) and inflammatory cells in bronchoalveolar lavage fluid (BALF). Differences in the classification of lung histo-pathology are noted frequently and may account for some of the difference in outcome for patients with SSc-ILD and IPF. Optimal treatment of SSc-ILD remains to be determined, but cyclophosphamide has been reported to be effective in a number of case series. A randomized controlled trial, the Scleroderma Lung Study (SLS), will be completed in 2005; the outcome of the SLS should define the efficacy of daily oral cyclophosphamide for SSc-ILD patients with alveolitis defined by BALF and HRCT.

The radiology of chronic lung disease in children

Chronic lung disease (CLD) in children represents a heterogeneous group of many distinct clinicopathological entities. The prevalence of CLD has increased in the past decade because of the more advanced and intensive respiratory support provided for compromised children and additionally the overall improved survival of preterm babies. The disorders which constitute CLD generally have a slow tempo of progression over many months or even years. The most common causes of CLD in children are cystic fibrosis (CF), and other causes of bronchiectasis (such as immunodeficiency, and in the third world, post-infective bronchiectasis, for example, measles), bronchopulmonary dysplasia (BPD) (or lung disease of prematurity), asthma, chronic gastro-oesophageal reflux/aspiration pneumonitis, and constrictive obliterative bronchiolitis.

Fibrosing alveolitis in systemic sclerosis: the need for early screening and treatment

Abnormalities in lung function occur in 70% of patients with systemic sclerosis (SSc). Fibrosing alveolitis in SSc (FASSc) is more commonly seen in the diffuse cutaneous form of SSc, particularly in the presence of antitopoisomerase antibodies (Scl70), and with the decreasing incidence of scleroderma renal crisis it is now the major cause of mortality in this patient population. Screening of patients recently diagnosed with SSc by pulmonary function tests and the performance of high resolution computed tomography when physiological abnormalities are identified has resulted in the identification of significant numbers of patients with early, asymptomatic FASSc. Whether these patients should be further investigated with a surgical lung biopsy or receive immunosuppression is unclear, because it cannot yet be reliably predicted who will develop progressive disease and the evidence to support the efficacy of treatment is not strong. The objective of the present article was to review the evidence to support the use of immunosuppressive therapy in FASSc and, based on these data, to propose an algorithm for the investigation and management of this difficult clinical problem.

Review article: gastro-oesophageal reflux disease -- how wide is its span?

Symptoms of gastro-oesophageal reflux disease are highly prevalent in Western countries; however, it is less certain how many individuals with heartburn have clinically relevant disease. Although the prevalence of gastro-oesophageal reflux disease in Asia is substantially lower, the incidence may be increasing. How much of this increase is explained by the increasing recognition of heartburn in clinical practice, dietary changes and increasing obesity, or the eradication of Helicobacter pylori, remains unclear. There has been speculation that endoscopy-negative reflux disease represents a separate entity from reflux oesophagitis (as defined by the Los Angeles classification), but the evidence that might support this proposal is unconvincing. Patients with chronic reflux symptoms have a higher risk of Barrett's oesophagus, and the increased risk of developing oesophageal adenocarcinoma in individuals with a long history of heartburn is also well documented, but whether this always occurs via Barrett's oesophagus is debatable. Moreover, treatment with standard-dose antisecretory therapies and anti-reflux surgery seems unlikely, based on current evidence, to reduce the cancer risk in patients with Barrett's oesophagus. Gastro-oesophageal reflux disease has also been implicated in an increasing array of other conditions, but arguably in these settings it is often over-diagnosed.

The role of gastroesophageal reflux in idiopathic pulmonary fibrosis

Fibroblast foci are indicative of idiopathic pulmonary fibrosis and appear to be a cellular attempt to repair the damaged alveolus. Although this progressive, often fatal, clinical syndrome is thought to be dependent on alveolar injury of unknown origin, significant clinical and preclinical evidence points to gastric acid as a causative harmful agent. Graded instillation of various forms of acid in several animal models resulted in aspiration-induced lung injury, including pulmonary fibrosis in pigs. Moreover, compelling clinical data suggest that a high percentage of patients with idiopathic pulmonary fibrosis also experience abnormal esophageal acid exposure, without necessarily experiencing the typical symptoms of gastroesophageal reflux disease (GERD). Aggressive, long-term therapeutic trials of patients with GERD and evaluation of the therapeutic effects on pulmonary disease will allow determination of the real influences of abnormal esophageal acid exposure in the development of idiopathic pulmonary fibrosis.

Severe gastroesophageal reflux is associated with reduced carbon monoxide diffusing capacity

OBJECTIVE

To assess whether severe gastroesophageal reflux (GER) is associated with abnormalities in lung function including measures of lung volume and gas diffusion.

METHODS

Data from 147 patients with obesity (body mass index [BMI] range, 31.7 to 70 kg/m(2)) who presented for obesity surgery was analyzed retrospectively. A questionnaire was completed preoperatively that included a history of GER, frequency and severity of symptoms, investigations, and medications used. A history of lung disease, sleep-disordered breathing, and smoking also was obtained. A physician who was blinded to lung function graded GER severity prospectively by the results of pH monitoring and/or gastroscopy, and medication use. Spirometry, lung volumes, and gas transfer were measured preoperatively.

RESULTS

Patients with severe GER had reduced levels of the diffusing capacity of the lung for carbon monoxide (DLCO) [21.1 mL/min/mm Hg; 95% confidence interval (CI), 18.9 to 23.2], as measured by CO transfer, compared with those patients without GER (26.3 mL/min/mm Hg; 95% CI, 24.4 to 28.2; p = 0.001). This remained significant after adjusting for age, gender, BMI, and smoking history. Gas transfer corrected for lung volume also was reduced in the group with severe GER (4.6 mL/min/mm Hg per L; 95% CI, 4.3 to 4.9) compared to the group without GER (5.3 mL/min/mm Hg per L; 95% CI, 5.1 to 5.5; p = 0.001). There was no significant difference in other measures of lung function.

CONCLUSIONS

Severe GER is associated with an impairment of gas exchange. This may be due to microaspiration of gastric acid or fluid into the airways.

Interstitial lung disease in scleroderma

Pulmonary fibrosis occurs most patients who have scleroderma. It progresses to severe restrictive lung disease in about 15% of patients and remains a major cause of death in this disease. Risks for developing pulmonary fibrosis include diffuse cutaneous scleroderma and anti-Scl-70 antibodies, and risks for developing progressive pulmonary fibrosis and death include low pulmonary function test results at presentation and lung inflammation. Early evaluation of the extent and severity of pulmonary fibrosis and the presence of lung inflammation is key, so that therapy can be given to patients who are at higher risk of progressive pulmonary fibrosis before they develop severe functional impairment occurs. Evaluation often includes pulmonary function tests, HRCT of the lungs, Doppler echocardiogram, and bronchoalveolar lavage. For patients who are unwilling or unable to participate in therapeutic trials that target pulmonary fibrosis in scleroderma, therapy with oral or intravenous cyclophosphamide is often given.