Two variants of occupational asthma separable by exhaled breath nitric oxide level.

Unlabelled: Exhaled nitric oxide (FE(NO)) has been used as a marker of asthmatic inflammation in non-occupational asthma, but some asthmatics have a normal FE(NO). In this study we investigated whether, normal FE(NO) variants have less reactivity in methacholine challenge and smaller peak expiratory flow (PEF) responses than high FE(NO) variants in a group of occupational asthmatics.

Methods: We measured FE(NO) and PD(20) in methacholine challenge in 60 workers currently exposed to occupational agents, who were referred consecutively to a specialist occupational lung disease clinic and whose serial PEF records confirmed occupational asthma.

Improving the quality of peak flow measurements for the diagnosis of occupational asthma.

Introduction: Serial measurements of peak expiratory flow (PEF) are recommended in the evidence-based review list as the first stage in objective confirmation of occupational asthma. Different centres have reported widely different success in obtaining records of sufficient data quantity for diagnosis. We investigated different methods of instruction and determined the return rate and quality of the resulting record for the diagnosis of occupational asthma.

Use of pulmonary function tests in the diagnosis of occupational asthma.

Objective: To discuss the different methods of assessing lung function measurements for the diagnosis of occupational asthma, focusing in particular on serial peak expiratory flow rate (PEFR) monitoring, including details on how PEFR records should be kept, plotted, and analyzed and limitations of the method.

Data Sources: Published studies on the use of diagnostic methods in occupational asthma, expert opinion, and recently obtained data from studies performed at a large occupational lung disease clinic. STUDY SOURCES: The expert opinion of the author was used to select the relevant data for review.