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Various reports have demonstrated the importance of small airway inflammation in the development of airflow limitation and progression of COPD. This hypothesis proposes that the pathogenesis of COPD mirrors a chronic inhalational dust-induced disease. The putative inorganic dust in cigarette smoke is aluminum silicate or kaolinite, a common component of clay soils. Kaolinite has been recovered in the alveolar macrophages of smokers and has been reported as a constituent of tobacco products. The origin of kaolinite in tobacco products remains unknown, and possible potential sources are proposed. On inhalation, kaolinite deposition in the distal lung may promote macrophage accumulation within the terminal airways leading to a respiratory bronchiolitis. In the susceptible smoker, important genetic, environmental, immunologic, and mechanical factors interact and modulate this small airway inflammation, ultimately leading to the pathologic lesion of emphysema. Further studies into the effects of kaolinite on macrophage function and the subsequent development of respiratory bronchiolitis could lead to prevention of COPD at its precursor lesion. [ABSTRACT FROM AUTHOR]

This case report describes a rare presentation of chronic cough secondary to endobronchial involvement with blue rubber bleb nevus syndrome (BRBNS) lesions. BRNBS is a rare syndrome characterized with cavernous hemangiomas involving the skin and GI tract. We report the case of a 37-year-old woman, with known BRBNS, who acquired an intractable cough with a radiograph revealing multiple pulmonary nodules. A bronchoscopy demonstrated various bluish, raised, and hypervascular lesions characteristic for BRBNS involving the right mainstem bronchus and segmental bronchi. To our knowledge, this is the first report of endobronchial involvement with BRBNS. [ABSTRACT FROM AUTHOR]

Background: Sepsis is a leading cause of hospitalization, and subsequent readmissions are frequent and costly. There is an expanding body of literature describing risk factors for readmissions in patients with sepsis. However, there are little data studying medically underserved patients who typically receive their care at a safety net hospital., Methods: In a retrospective cohort study, we evaluated 1355 sepsis survivors at risk of hospital readmission in fiscal year 2013 at a safety net hospital. We described patient characteristics during their initial and readmission hospitalizations and analyzed risk factors associated with 30-day readmission., Results: The 30-day readmission rate among sepsis survivors was 22.6%. Comorbid conditions associated with readmissions included end-stage renal disease (odds ratio [OR], 1.26; 95% confidence interval [CI], 1.17-1.36), malignancy (OR, 1.14; 95% CI, 1.08-1.21), and cirrhosis (OR, 1.11; 95% CI, 1.02-1.20). Bacteremia during the initial hospitalization (OR, 1.07; 95% CI, 1.01-1.15) and being discharged with a vascular catheter (OR, 1.10; 95% CI, 1.01-1.20) were associated with readmission. Less severe sepsis during the initial hospitalization was associated with a reduced risk of 30-day readmission (OR, 0.91; 95% CI, 0.87-0.94)., Conclusions: At a safety net hospital, patients who survived their initial sepsis hospitalization had a 30-day readmission rate to our institution of 22.6% that is comparable to rates described in prior studies. Readmission was commonly due to infection. Factors associated with readmission included multiple comorbid medical conditions, bacteremia, and being discharged with a vascular catheter. Further studies in this population are needed to determine potential modifiability of these risk factors in an attempt to reduce sepsis readmissions.

Introduction: PIPF-002 was a phase 2, multicenter, open-label study of pirfenidone in patients with idiopathic pulmonary fibrosis (IPF) or other types of pulmonary fibrosis (PF). PIPF-002 terminated after pirfenidone became commercially available in the United States. The goal of PIPF-002 was to characterize the long-term safety of pirfenidone in these patients., Methods: Between August 2003 and September 2006, 83 patients (IPF: 81, PF: 2) enrolled. Patients received pirfenidone in three divided doses daily, with the maintenance dose and schedule determined by enrollment group assignment. Treatment continued until patient withdrawal or study termination (2015). Treatment-emergent adverse events (TEAEs) were assessed by descriptive statistics., Results: At baseline, median age was 70 years, mean percent predicted forced vital capacity was 67.7%, 33.7% of patients had cardiac disorders, 51.8% had gastroesophageal reflux disease, and 63.9% were receiving concomitant prednisone. Median pirfenidone dose and exposure duration were 2400 mg/day and 3.0 years, respectively. Cumulative total exposure was 279.7 patient-exposure years (PEY). Most patients (98.8%) reported ≥ 1 TEAE, with an overall incidence rate of 460.5 per 100 PEY. The most frequent TEAEs (incidence rate per 100 PEY) were nausea (23.6), IPF progression (16.1), fatigue (11.8), dyspnea (11.4), upper respiratory tract infection (11.4), and cough (10.7). Serious TEAEs were reported in 49 patients; the most frequent serious TEAEs were IPF progression and pneumonia. The most common reason for discontinuation was TEAEs (35 patients; 12.5 patients per 100 PEY), most frequently IPF progression and nausea. Overall, 21 patients died (7.5 per 100 PEY); 16 deaths were IPF-related., Conclusions: Long-term safety and tolerability of pirfenidone findings in this study were consistent with the known safety profile of pirfenidone; no new safety signals were identified. These data support the continued use of pirfenidone in patients with IPF., Funding: F. Hoffmann-La Roche Ltd./Genentech, Inc., Trial Registration: ClinicalTrials.gov identifier, NCT00080223. Plain language summary available for this article.

Idiopathic pulmonary fibrosis (IPF) is an age-related disease featuring progressive lung scarring. To elucidate the molecular basis of IPF, we performed exome sequencing of familial kindreds with pulmonary fibrosis. Gene burden analysis comparing 78 European cases and 2,816 controls implicated PARN, an exoribonuclease with no previous connection to telomere biology or disease, with five new heterozygous damaging mutations in unrelated cases and none in controls (P = 1.3 × 10(-8)); mutations were shared by all affected relatives (odds in favor of linkage = 4,096:1). RTEL1, an established locus for dyskeratosis congenita, harbored significantly more new damaging and missense variants at conserved residues in cases than in controls (P = 1.6 × 10(-6)). PARN and RTEL1 mutation carriers had shortened leukocyte telomere lengths, and we observed epigenetic inheritance of short telomeres in family members. Together, these genes explain ~7% of familial pulmonary fibrosis and strengthen the link between lung fibrosis and telomere dysfunction.

Background: Short telomere lengths are found in a subset of patients with idiopathic pulmonary fibrosis, but their clinical significance is unknown. Our aim was to investigate whether patients with various blood leucocyte telomere lengths had different overall survival., Methods: In this observational cohort study, we enrolled patients with interstitial lung disease from Dallas, TX (primary cohort), and from Chicago, IL, and San Francisco, CA (replication cohorts). We obtained genomic DNA samples from unrelated healthy controls in Dallas, TX, and spouses of patients were also enrolled as an independent control group. Telomere lengths were measured in genomic DNA samples isolated from peripheral blood obtained at the time of the initial enrolment assessment. The primary endpoint was transplant-free survival (ie, time to death or lung transplantation) in the Dallas cohort. Findings were validated in the two independent idiopathic pulmonary fibrosis cohorts (Chicago and San Francisco)., Findings: 370 patients were enrolled into the Dallas cohort between June 17, 2003, and Aug 25, 2011. The 149 patients with idiopathic pulmonary fibrosis had shorter telomere lengths than did the 195 healthy controls (mean age-adjusted log-transformed ratio of telomere to single copy gene was -0.16 [SD 0.23] vs 0.00 [0.18]; p<0.0001); however, telomere lengths of the Dallas patients with idiopathic pulmonary fibrosis (1.33 [SD 0.25]) were similar to the 221 patients with other interstitial lung disease diagnoses (1.46 [0.24]) after adjusting for age, sex, and ethnicity (p=0.47). Telomere length was independently associated with transplant-free survival time for patients with idiopathic pulmonary fibrosis (HR 0.22 [95% CI 0.08-0.63]; p=0.0048), but not for patients with interstitial lung disease diagnoses other than idiopathic pulmonary fibrosis (HR 0.73 [0.16-3.41]; p=0.69). The association between telomere length and survival in patients with idiopathic pulmonary fibrosis was independent of age, sex, forced vital capacity, or diffusing capacity of carbon monoxide, and was replicated in the two independent idiopathic pulmonary fibrosis replication cohorts (Chicago cohort, HR 0.11 [0.03-0.39], p=0.00066; San Francisco cohort, HR 0.25 [0.07-0.87], p=0.029)., Interpretation: Shorter leucocyte telomere lengths are associated with worse survival in idiopathic pulmonary fibrosis. Additional studies will be needed to establish clinically relevant thresholds for telomere length and how this biomarker might affect risk stratification of patients with idiopathic pulmonary fibrosis., Funding: US National Heart, Lung, and Blood Institute, National Center for Advancing Translational Sciences, Harroun Family Foundation, and Nina Ireland Lung Disease Program., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: Accurate, timely and automated identification of patients at high risk for severe clinical deterioration using readily available clinical information in the electronic medical record (EMR) could inform health systems to target scarce resources and save lives., Methods: We identified 7,466 patients admitted to a large, public, urban academic hospital between May 2009 and March 2010. An automated clinical prediction model for out of intensive care unit (ICU) cardiopulmonary arrest and unexpected death was created in the derivation sample (50% randomly selected from total cohort) using multivariable logistic regression. The automated model was then validated in the remaining 50% from the total cohort (validation sample). The primary outcome was a composite of resuscitation events, and death (RED). RED included cardiopulmonary arrest, acute respiratory compromise and unexpected death. Predictors were measured using data from the previous 24 hours. Candidate variables included vital signs, laboratory data, physician orders, medications, floor assignment, and the Modified Early Warning Score (MEWS), among other treatment variables., Results: RED rates were 1.2% of patient-days for the total cohort. Fourteen variables were independent predictors of RED and included age, oxygenation, diastolic blood pressure, arterial blood gas and laboratory values, emergent orders, and assignment to a high risk floor. The automated model had excellent discrimination (c-statistic=0.85) and calibration and was more sensitive (51.6% and 42.2%) and specific (94.3% and 91.3%) than the MEWS alone. The automated model predicted RED 15.9 hours before they occurred and earlier than Rapid Response Team (RRT) activation (5.7 hours prior to an event, p=0.003), Conclusion: An automated model harnessing EMR data offers great potential for identifying RED and was superior to both a prior risk model and the human judgment-driven RRT.

Background: Telomerase is an enzyme that catalyzes the addition of nucleotides on the ends of chromosomes. Rare loss of function mutations in the gene that encodes the protein component of telomerase (TERT) have been described in patients with idiopathic pulmonary fibrosis (IPF). Here we examine the telomere lengths and pulmonary fibrosis phenotype seen in multiple kindreds with heterozygous TERT mutations., Methods and Findings: We have identified 134 individuals with heterozygous TERT mutations from 21 unrelated families. Available medical records, surgical lung biopsies and radiographs were evaluated retrospectively. Genomic DNA isolated from circulating leukocytes has been used to measure telomere lengths with a quantitative PCR assay. We find that telomere lengths of TERT mutation carriers decrease in an age-dependent manner and show progressive shortening with successive generations of mutation inheritance. Family members without TERT mutations have a shorter mean telomere length than normal, demonstrating epigenetic inheritance of shortened telomere lengths in the absence of an inherited TERT mutation. Pulmonary fibrosis is an age-dependent phenotype not seen in mutation carriers less than 40 years of age but found in 60% of men 60 years or older; its development is associated with environmental exposures including cigarette smoking. A radiographic CT pattern of usual interstitial pneumonia (UIP), which is consistent with a diagnosis of IPF, is seen in 74% of cases and a pathologic pattern of UIP is seen in 86% of surgical lung biopsies. Pulmonary fibrosis associated with TERT mutations is progressive and lethal with a mean survival of 3 years after diagnosis. Overall, TERT mutation carriers demonstrate reduced life expectancy, with a mean age of death of 58 and 67 years for males and females, respectively., Conclusions: A subset of pulmonary fibrosis, like dyskeratosis congenita, bone marrow failure, and liver disease, represents a "telomeropathy" caused by germline mutations in telomerase and characterized by short telomere lengths. Family members within kindreds who do not inherit the TERT mutation have shorter telomere lengths than controls, demonstrating epigenetic inheritance of a shortened parental telomere length set-point.

Increased pulmonary production of prostaglandin I2 (prostacyclin) by lung-specific overexpression of prostacyclin synthase decreases lung tumor incidence and multiplicity in chemically induced murine lung cancer models. We hypothesized that pulmonary prostacyclin synthase overexpression would prevent lung carcinogenesis in tobacco-smoke exposed mice. Murine exposure to tobacco smoke is an established model of inducing pulmonary adenocarcinomas and allows for the testing of potential chemopreventive strategies. Transgenic FVB/N mice with lung-specific prostacyclin synthase overexpression were exposed to mainstream cigarette smoke for 22 weeks and then held unexposed for an additional 20 weeks. All of the exposed animals developed bronchiolitis analogous to the respiratory bronchiolitis seen in human smokers. The transgenic mice, when compared with smoke-exposed transgene negative littermates, had significant decreases in tumor incidence and multiplicity. Significantly fewer transgenics (6 of 15; 40%) developed tumors compared with the tumor incidence in wild-type littermates (16 of 19; 84%; Fisher's exact test, P = 0.012). Tumor multiplicity was also significantly decreased in the transgenic animals (tg+ = 0.4 +/- 0.5 versus wild-type = 1.2 +/- 0.86 tumors/mouse; P < 0.001). Targeted prostaglandin levels at the time of sacrifice revealed significantly elevated prostaglandin I2 levels in the transgenic animals, coupled with significantly decreased prostaglandin E2 levels. Gene expression analysis of isolated type II pneumocytes suggests potential explanations for the observed chemoprevention, with Western blot analysis confirming decreased expression of cytochrome p450 2e1. These studies extend our previous studies and demonstrate that manipulation of prostaglandin production distal to cyclooxygenase significantly reduces lung carcinogenesis in a tobacco smoke exposure model, and gene expression studies show critical alterations in antioxidation, immune response, and cytokine pathways.

The epithelium of the alveolus and distal airway meets unique requirements, functioning as a gas exchange membrane and barrier to alveolar flooding by vascular contents as well as to bloodstream contamination by airborne toxins and pathogens. Gene products specifically expressed by this epithelium, notably the surfactant apoproteins, have had important clinical application. No cell surface antigen specific for alveolar type II and Clara cells has been described. We report the biochemical characterization, tissue and developmental expression, and upregulation by injury of a 172 kD protein recognized by a monoclonal antibody, 3F9, synthesized in response to immunization with freshly isolated rat alveolar type II cells. p172 is expressed in a polarized fashion by the apical surface of rat alveolar type II and Clara cells. An immunohistochemical survey of various rat tissues and organs reveals lung specificity. p172 is first detectable in rare epithelial cells at 19 days of gestation, a time when the fully differentiated alveolar type II cell is identified by the first detection of lamellar bodies. There is a dramatic increase in p172 expression just prior to birth. Hyperoxic lung injury results in increased expression of p172. The upregulation of p172 by hyperoxia and its cell-specific expression suggests an important adaptive function.