Jason Sapp, MD

Although the results of a thorough history and physicalexamination often suggest the diagnosis of asthma, confirmatorytesting is required and may be helpful in more subtlecases. Spirometry before and after bronchodilator administrationis the first step for the initial diagnosis; it also is an importantcomponent of the long-term assessment of asthma control.When the results of spirometry are normal in a patient in whomasthma is suspected, bronchoprovocation challenge testingwith methacholine is generally considered the next diagnosticstep. Numerous alternative methods of bronchoprovocationtesting have been developed, such as the challenge with adenosine5'-monophosphate. Novel methods such as the forced oscillationtechnique and the measurement of exhaled nitric oxidehold promise for more effective diagnosis and monitoringof asthma in the future. (J Respir Dis. 2008;29(4):157-169)