Impulse Oscillometry as an Alternative Lung Function Test for Hospitalized Adults.

BACKGROUND: Impulse oscillometry (IOS) is a noninvasive technique that measures lung physiology independently of patient effort. In the present study, we aimed to investigate the utility of IOS parameters in comparison with pulmonary function testing (PFT) among hospitalized subjects, with emphasis on obstructive and small airway diseases. METHODS: Sixty-one subjects hospitalized either with unexplained dyspnea or for pre-surgery evaluation were included in the study. All subjects underwent PFTs and IOS test. The correlation between IOS results and PFTs was examined in different subgroups. The ability of IOS parameters to predict abnormal PFTs was evaluated using the area under the receiver operating characteristic (ROC) curve, and optimal cutoff values were calculated. RESULTS: IOS results were found to correlate with PFT values. Subgroup analysis revealed that these correlations were higher in younger (age < 70) and non-obese (body mass index < 25kg/m2) subjects. The resonant frequency was an independent predictor and had the best predictive ability for abnormal FEV1/FVC (area under the ROC curve 0.732 [95% CI 0.57-0.90], optimal cutoff 17 Hz, 87% sensitivity, 62% specificity) and abnormal forced expiratory flow during the middle half of the FVC maneuver (area under the ROC curve 0.667 [95% CI 0.53-0.81], optimal cutoff 15 Hz, 77% sensitivity, 54% specificity). Area of reactance and the difference in respiratory resistance at 5 Hz and 20 Hz also showed a good predictive ability for abnormal FEV1/FVC (area under the ROC curve 0.716 and 0.730, respectively). CONCLUSIONS: We found that the IOS performed well in diagnosing small airway and obstructive diseases among hospitalized subjects. IOS might serve as an alternative to standard PFTs in non-cooperative or dyspneic hospitalized patients.

Chronic beryllium disease among dental technicians in Israel.

BACKGROUND AND AIM: The potential risks of beryllium use in the dental industry have been recognized for some time. This is the first case series that focuses on the effect of a number of potentially harmful effects of substances that induce lung disease among dental technicians with emphasis on beryllium as a major risk factor in the work environment of dental technicians. METHODS: All the dental technicians consecutively recruited to this study had past occupational exposure to beryllium. They were evaluated in order to confirm immunological evidence of beryllium exposure for differential diagnosis between sarcoidosis and chronic beryllium disease (CBD). They were tested for beryllium sensitization by the beryllium lymphocyte proliferation test (BeLPT), and underwent lung function and induced sputum (IS) studies. Each had earlier undergone a comprehensive evaluation that included high-resolution computerized tomography, bronchoscopy and transbronchial biopsy to establish the final diagnosis of their condition. RESULTS: There were 24 enrollees (mean age 49.7 +/- 13.7 years, 17 males, 7 females) of whom 12 (50%) had positive BeLPT findings and were finally diagnosed as suffering from CBD, 7 (29%) had negative BeLPT findings and were diagnosed as suffering from another pulmonary pathology (sarcoidosis, chronic obstructive pulmonary disease, rejection of transplanted lung), and 5 (20.8%) had negative BeLPT findings and were diagnosed as being free of pulmonary disease. CONCLUSION: This case series study demonstrates that dental technicians are exposed to beryllium and various other occupational dusts and chemicals and are at high risk of developing CBD and other lung diseases. Our findings emphasize the need for awareness of the medical community to detect occupation related diseases in this profession.

Function associated transforming growth factor-beta gene polymorphism in chronic beryllium disease.

Chronic beryllium disease (CBD) is a rare occupational, granulomatous lung disease clinically resembling sarcoidosis. The immune response to beryllium is thought to depend on genetic susceptibility. Although a glutamic acid in position 69 of the human leukocyte antigen-DP beta chain (HLA-DPB1-Glu69) is associated with the development of CBD, it cannot fully explain susceptibility. It is likely that additionally other genes are involved in regulating the immune and inflammatory response in the pathogenesis of this disease. Functional gene polymorphisms (PMs) of the tumor necrosis factor (TNF)A and transforming growth factor (TGF) beta(1) genes are suspected to modify the course of granulomatous disorders. We analyzed the TGF-beta(1) (codon 25) PM in 59 patients with CBD and 164 matched healthy controls, from two groups of European/Israeli and United States origin. Additionally, patients were genotyped for HLA class II gene variants and the TNFA (-308) PM. The most significant results were found for the TGF-beta(1) (codon 25) PM with a shift towards the low producing non-GG genotypes in the subgroup of European and Israeli patients with CBD (62.50% vs. 13.82% in healthy controls; P<0.001). This phenomenon was not observed in the group from the United States. Moreover, TGF-beta(1) (codon 25) PM genotype frequencies from United States CBD patients differed significantly from those of European and Israeli patients. In contrast, increased frequencies for the high producing TNFA2 allele were found only in the patients from the United States (28.20% vs. 8.96% in healthy controls; P<0.005) but not in the group of Europe and Israel. In conclusion, the increase in TGF-beta(1) (codon 25) PM genotype frequency associated with a low TGF-beta release suggests that immunoregulatory cytokines such as TGF-beta are involved in the pathogenesis of CBD. Moreover, based on the interaction of gene PMs associated with the control of the immune response, such as TNF-alpha and TGF-beta(1), with a specific immune response gene such as HLA-DPB1-Glu69 or other HLA-class II PMs driving the immune response to Be, the present data suggest that a combination of different genetic backgrounds determine susceptibility for the same immunopathological reaction and disease.