Airway Diseases Related to the Use of Cleaning Agents in Occupational Settings.

Exposure to disinfectants and cleaning products (DCPs) is now a well-established risk factor for work-related asthma (WRA). However, questions remain on the specific causal agents and pathophysiological mechanisms. Few studies have also reported an association between DCPs and rhinitis or chronic obstructive pulmonary disease. This review discusses the recent evidence pertaining to airway diseases attributable to occupational exposure to DCPs. In contrast to other agents, the incidence of WRA due to DCPs has increased over time. The use of DCPs in spray form has clearly been identified as an added risk factor. The mechanisms for WRA associated with DCPs remain poorly studied; however, both allergic and nonallergic responses have been described, with irritant mechanisms thought to play a major role. An early diagnostic workup based on clinical assessment accompanied by evaluation of lung function and immunological and airway inflammatory markers is important to guide optimal care and exposure avoidance to the implicated agent. Future research should focus on the effects of "green" products, pathophysiological mechanisms, and quantitative exposure assessment including the use of barcode-based methods to identify specific agents. There is an urgent need to strengthen preventive measures and interventions to reduce the burden of airway diseases associated with DCPs.

Efficacy of bronchial thermoplasty in patients with severe asthma and frequent severe exacerbations: A randomized controlled study✰.

BACKGROUND: Bronchial thermoplasty (BT) is a bronchoscopic procedure for patients with severe uncontrolled asthma, but randomized controlled studies of its efficacy in severe asthma with frequent exacerbations are lacking. The current aim was to assess BT efficacy in this patient population. METHODS: Thirty patients with asthma (GINA 5) who had experienced at least four severe exacerbations in the preceding year were randomized to BT (n = 15) or control groups (n = 15). All patients had four follow-up visits over the following 15 months, corresponding to 3, 6, 9, and 12 months after the last procedure for the BT group. The primary outcome was number of exacerbations at 15 months after inclusion (i.e. 12 months after bronchial thermoplasty). RESULTS: All but three patients had received an asthma biologic without receiving benefit. In the year preceding enrollment, patients in the BT group had an average of five exacerbations, compared with six among controls. For patients in the BT group, oral steroid intake was 9.3 mg/d, compared with 11.0 mg/d among controls. The BT group had 1.58 fewer severe exacerbations (mean, 6.09) compared with controls (mean, 8.28) in the 12-month period after the therapy (p = 0.047). Oral steroid intake during follow-up after BT was significantly lower in the BT group (ratio vs controls: 0.61; p = 0.0002). Quality-of-life measures between inclusion and the last visit were significantly improved in the BT group, but not among controls. Few mild to moderate adverse events were reported, and all were controlled within days. CONCLUSION: In patients with severe asthma and frequent severe exacerbations, BT significantly decreased the rate of severe exacerbations and oral steroid intake and led to improved quality of life during the 15 months after inclusion. BT appears to offer a therapeutic option for severe asthma with frequent exacerbations.

Diagnostic Accuracy of Specific IgE Against Wheat and Rye in Flour-Induced Occupational Asthma.

BACKGROUND: Assessment of IgE-mediated sensitization to flour allergens is widely used to investigate flour-induced occupational asthma. The diagnostic efficiency of detecting specific IgE antibodies (sIgEs) against wheat and rye flour, however, has not been thoroughly compared with other diagnostic procedures. OBJECTIVE: We sought to evaluate the diagnostic accuracy of sIgE against wheat and rye compared with specific inhalation challenge (SIC) with flour as the reference standard. METHODS: This retrospective multicenter study included 264 subjects who completed an SIC with flour in eight tertiary centers, of whom 205 subjects showed a positive SIC result. RESULTS: Compared with SIC, sIgE levels of 0.35 kUA/L or greater against wheat and rye provided similar sensitivities (84% to 85%, respectively), specificities (71% to 78%), positive predictive values (91% to 93%), and negative predictive values (56% to 61%). Increasing the threshold sIgE value to 5.10 kUA/L for wheat and to 6.20 kUA/L for rye provided a specificity of 95% or greater and further enhanced the positive predictive value to 98%. Among subjects with a positive SIC, those who failed to demonstrate sIgE against wheat and rye (n = 26) had significantly lower total serum IgE level and blood and sputum eosinophil counts and a lesser increase in postchallenge FeNO compared with subjects with a detectable sIgE. CONCLUSION: High levels of sIgE against wheat and/or rye flour strongly support a diagnosis of flour-induced occupational asthma without the need to perform an SIC. The absence of detectable sIgE against wheat and rye in subjects with a positive SIC seems to be associated with lower levels of TH2 biomarkers.