Cecile S. Rose

Genome-wide search for sarcoidosis susceptibility genes in African Americans

Sarcoidosis, a systemic granulomatous disease of unknown etiology, likely results from an environmental insult in a genetically susceptible host. In the US, African Americans are more commonly affected with sarcoidosis and suffer greater morbidity than Caucasians. We searched for sarcoidosis susceptibility loci by conducting a genome-wide, sib pair multipoint linkage analysis in 229 African-American families ascertained through two or more sibs with a history of sarcoidosis. Using the Haseman–Elston regression technique, linkage peaks with P-values less than 0.05 were identified on chromosomes 1p22, 2p25, 5p15-13, 5q11, 5q35, 9q34, 11p15 and 20q13 with the most prominent peak at D5S2500 on chromosome 5q11 (P=0.0005). We found agreement for linkage with the previously reported genome scan of a German population at chromosomes 1p and 9q. Based on the multiple suggestive regions for linkage found in our study population, it is likely that more than one gene influences sarcoidosis susceptibility in African Americans. Fine mapping of the linked regions, particularly on chromosome 5q, should help to refine linkage signals and guide further sarcoidosis candidate gene investigation.

Clinical and radiologic manifestations of hypersensitivity pneumonitis

Hypersensitivity pneumonitis (HP) is an inflammatory interstitial lung disease caused by recurring exposure to a variety of occupational and environmental antigens. It features widely variable clinical, radiologic, and histopathologic findings. Because the clinical findings of HP mimic multiple other diseases, a high degree of clinical suspicion and a thorough occupational and environmental history are essential for accurate diagnosis. There is no single pathognomonic feature for HP; rather, diagnosis relies on a constellation of clinical, radiologic, and pathologic findings. The radiologic manifestations, particularly the high-resolution computed tomography (HRCT) pattern, provide important clues and frequently point clinicians towards the correct diagnosis. The HRCT findings in HP may include ground-glass opacification, centrilobular nodules, air trapping (mosaic pattern), fibrosis, emphysema, or more frequently a combination of these. The combination of a mosaic pattern with ground-glass opacification and centrilobular nodules is particularly suggestive of the diagnosis. The best long-term prognosis is achieved with early diagnosis and removal from exposure.

Coal Mine Dust Lung Disease. New Lessons from an Old Exposure

Coal mining remains a sizable industry, with millions of working and retired coal miners worldwide. This article provides an update on recent advances in the understanding of respiratory health issues in coal miners and focuses on the spectrum of disease caused by inhalation of coal mine dust, termed coal mine dust lung disease. In addition to the historical interstitial lung diseases (coal workers pneumoconiosis, silicosis, and mixed dust pneumoconiosis), coal miners are at risk for dust-related diffuse fibrosis and chronic airway diseases, including emphysema and chronic bronchitis. Recent recognition of rapidly progressive pneumoconiosis in younger miners, mainly in the eastern United States, has increased the sense of urgency and the need for vigilance in medical research, clinical diagnosis, and exposure prevention. Given the risk for disease progression even after exposure removal, along with few medical treatment options, there is an important role for chest physicians in the recognition and management of lung disease associated with work in coal mining.

Job and industry classifications associated with sarcoidosis in a case-control etiologic study of sarcoidosis (ACCESS)

Objectives: Objective: To determine whether specific occupations and industries may be associated with sarcoidosis. Methods: A Case Control Etiologic Study of Sarcoidosis (ACCESS) obtained occupational and environmental histories on 706 newly diagnosed sarcoidosis cases and matched controls. We used Standard Industrial Classification (SIC) and Standard Occupational Classification (SOC) to assess occupational contributions to sarcoidosis risk. Results: Univariable analysis identified elevated risk of sarcoidosis for workers with industrial organic dust exposures, especially in Caucasian workers. Workers for suppliers of building materials, hardware, and gardening materials were at an increased risk of sarcoidosis as were educators. Work providing childcare was negatively associated with sarcoidosis risk. Jobs with metal dust or metal fume exposures were negatively associated with sarcoidosis risk, especially in Caucasian workers. Conclusions: In this study, we found that exposures in particular occupational settings may contribute to sarcoidosis risk.

Relationship of environmental exposures to the clinical phenotype of sarcoidosis

STUDY OBJECTIVES Sarcoidosis is a granulomatous disorder with heterogeneous clinical manifestations, which are potentially reflective of a syndrome with different etiologies leading to similar histologic findings. We examined the relationship between environmental and occupational exposures, and the clinical phenotype of sarcoidosis. DESIGN We performed a cross-sectional study of incident sarcoidosis cases that had been identified by A Case Control Etiologic Study of Sarcoidosis. Subjects were categorized into the following two groups: (1) pulmonary-only disease; and (2) systemic disease (with or without pulmonary involvement). Logistic regression was used to examine the associations of candidate exposures with clinical phenotype. SETTING Ten academic medical centers across the United States. PATIENTS The current study included 718 subjects in whom sarcoidosis had been diagnosed within 6 months of study enrollment. Patients met the following criteria prior to enrollment: (1) tissue confirmation of noncaseating granulomas on tissue biopsy on one or more organs within 6 months of study enrollment with negative stains for acid-fast bacilli and fungus; (2) clinical signs or symptoms that were consistent with sarcoidosis; (3) no other obvious explanation for the granulomatous disease; and (4) age > 18 years. MEASUREMENTS AND RESULTS Several exposures were associated with significantly less likelihood of having extrapulmonary disease in multivariate analysis, including agricultural organic dusts and wood burning. The effects of many of these exposures were significantly different in patients of different self-defined race. CONCLUSIONS The differentiation of sarcoidosis subjects on the basis of clinical phenotypes suggests that these subgroups may have unique environmental exposure associations. Self-defined race may play a role in the determination of the effect of certain exposures on disease phenotypes.

Nontuberculous Mycobacteria in Aerosol Droplets and Bulk Water Samples from Therapy Pools and Hot Tubs

Hot tub exposure has been causally associated with a steroid-responsive, granulomatous lung disease featuring nontuberculous mycobacterial (NTM) growth in both clinical and environmental samples. Little is known regarding prevalence of and risk factors for NTM-contamination and associated illness in these settings. In this study, the frequency of NTM growth and aerosolization in 18 public hot tubs and warm water therapy pools and the factors associated with mycobacterial growth were analyzed. Each site was characterized by water chemistry analysis; a questionnaire on maintenance, disinfection, and water quality; and air and water sampling for quantitative NTM culture. NTM were detected in air or water from 13/18 (72%) sites; a strong correlation was found between the maximum air and water NTM concentrations (rho 0.49, p = 0.04). Use of halogen (chlorine or bromine) disinfection was associated with significantly lower air and water concentrations of NTM compared with disinfection using ultraviolet light and hydrogen peroxide (p = 0.01–0.04). Higher water turnover rates were also associated with lower air and water NTM concentrations (p = 0.02–0.03). These findings suggest that NTM are frequently detectable in the air and water of spas and therapy pools and that particular maintenance and disinfection approaches affect NTM bioaerosol concentrations in these settings.

TGF-β1 Variants in Chronic Beryllium Disease and Sarcoidosis

Evidence suggests a genetic predisposition to chronic beryllium disease (CBD) and sarcoidosis, which are clinically and pathologically similar granulomatous lung diseases. TGF-β1, a cytokine involved in mediating the fibrotic/Th1 response, has several genetic variants which might predispose individuals to these lung diseases. We examined whether certain TGF-β1 variants and haplotypes are found at higher rates in CBD and sarcoidosis cases compared with controls and are associated with disease severity indicators for both diseases. Using DNA from sarcoidosis cases/controls from A Case Control Etiologic Study of Sarcoidosis Group (ACCESS) and CBD cases/controls, TGF-β1 variants were analyzed by sequence-specific primer PCR. No significant differences were found between cases and controls for either disease in the TGF-β1 variants or haplotypes. The −509C and codon 10T were significantly associated with disease severity indicators in both CBD and sarcoidosis. Haplotypes that included the −509C and codon 10T were also associated with more severe disease, whereas one or more copies of the haplotype containing the −509T and codon 10C was protective against severe disease for both sarcoidosis and CBD. These studies suggest that the −509C and codon 10T, implicated in lower levels of TGF-β1 protein production, are shared susceptibility factors associated with more severe granulomatous disease in sarcoidosis and CBD. This association may be due to lack of down-regulation by TGF-β1, although future studies will be needed to correlate TGF-β1 protein levels with known TGF-β1 genotypes and assess whether there is a shared mechanisms for TGF-β1 in these two granulomatous diseases.

Associations between radiographic findings and spirometry in a community exposed to Libby amphibole

Background Among asbestos-exposed individuals, abnormal spirometry is usually associated with parenchymal abnormalities or diffuse pleural thickening. Localised pleural thickening (LPT), the most common abnormality associated with asbestos exposure, is typically thought to be a marker of exposure with little clinical consequence. Our objective was to determine if abnormal spirometry is associated with LPT independent of other abnormalities, using data from community-based screening conducted in Libby, Montana. Methods Subjects were a subset of screening participants comprising persons with interpretable spirometry and chest radiograph results (n=6475). Chest radiographs were independently evaluated by two or three B readers, and participants were classified by mutually exclusive categories of spirometry outcome: normal, restriction, obstruction or mixed defect. Results Restrictive spirometry was strongly associated with parenchymal abnormalities (OR 2.9; 95% CI 1.4 to 6.0) and diffuse pleural thickening (OR 4.1; 95% CI 2.1 to 7.8). Controlling for the presence of these abnormalities as well as age, smoking status and other covariates, restrictive spirometry was also associated with LPT (OR 1.4; 95% CI 1.1 to 1.8). The risk of restrictive spirometric findings correlated with the severity of LPT. Conclusions In this large community-based screening cohort, restrictive spirometry is significantly associated with LPT, indicating that this abnormality may result in lung function impairment. Physicians treating patients exposed to Libby amphibole should be aware that LPT may have functional consequences.

Overview and recommendations for medical screening and diagnostic evaluation for postdeployment lung disease in returning US warfighters.

Objective: To review inhalational exposures and respiratory disease risks in US military personnel deployed to Iraq and Afghanistan and to develop consensus recommendations for medical screening and diagnostic referral. Methods: A Working Group of physicians and exposure scientists from academia and from the Departments of Defense and Veterans Affairs was convened in February 2010. Results: Despite uncertainty about the number of people affected and risk factors for adverse pulmonary outcomes in this occupational setting, the Working Group recommended: (1) standardized approaches to pre- and postdeployment medical surveillance; (2) criteria for medical referral and diagnosis; and (3) case definitions for major deployment-related lung diseases. Conclusions: There is a need for targeted, practical medical surveillance for lung diseases and for a standardized diagnostic approach for all symptomatic deployed personnel.

Efficacy of mycophenolate mofetil in sarcoidosis

BACKGROUND Immunosuppressive (IS) therapy is indicated to treat progressive sarcoidosis, but randomized controlled trials to guide physicians in the use of steroid sparing agents are lacking. The aim of this retrospective study was to examine the role of mycophenolate mofetil (MMF) as an alternative therapy in the treatment of sarcoidosis. METHODS A retrospective chart review of all patients who had been prescribed MMF between January 2008 and October 2011 was conducted. Patients with insufficient data or who had another IS therapy initiated concomitantly with MMF, including prednisone, were excluded. Physiological data obtained at the time MMF therapy was initiated as well as six and twelve months before and after therapy was extracted. Longitudinal analyses of the effect of MMF on changes in pulmonary function at MMF start, 6 months, 12 months pre and post MMF therapy were conducted. RESULTS 37/76 patients met our inclusion/exclusion criteria. There were no statistically significant changes in PFT measurements pre and post MMF therapy. We did find a trend (p = 0.07) towards improvement in DLCO 12 months pre and post MMF in patients who were started on MMF due to intolerance to previous IS therapy compared to those who were unresponsive to their previous IS therapy. We also noted a reduction in prednisone dose in those treated with MMF. CONCLUSION MMF appears to offer no extra benefit to sarcoidosis patients unresponsive to previous steroid-sparing agents, but may be beneficial in patients intolerant to their previous steroid-sparing agent. Additional studies investigating the efficacy of MMF as the initial steroid-sparing agent are needed to further clarify the role of MMF in sarcoidosis.