Hara J. et al¹ discussed the aetiologies of chronic cough using the pathophysiological diagnostic procedure and determined the outcomes of treatment administered based on aetiology.

They retrospectively reviewed the medical records of patients with chronic cough and analyzed the pathophysiological diagnostic procedure-based aetiologies and corresponding treatments. The pathophysiological diagnostic procedure used was the capsaicin cough test, methacholine cough test, bronchial reversibility test, bronchial responsiveness test, chest and sinus CT, and sputum examinations.

The diagnostic criteria for establishing various conditions in the study were as follows-

The observations of the study were as follows-

• Out of 300 patients who underwent the diagnostic procedure, aetiologies of chronic cough were established in 297 patients (99.0%).
• The remaining 1.0% showed all results of the diagnostic procedure within normal limits, so their aetiologies were evaluated using the therapeutic diagnostic procedure.
• 25% of patients showed complete resolution of cough within 5.0 weeks.

Thus they regarded pathophysiological diagnostic procedure to provide a rapid and objective diagnosis of chronic cough aetiology, leading to superior treatment results compared to the therapeutic diagnostic procedure.

Source: Hara J, Fujimura M, Yasui M, Takeda R, Ohkura N. Aetiologies of chronic cough diagnosed using a pathophysiologic diagnostic procedure and their treatment outcomes. medRxiv 2021. doi: https://doi.org/10.1101/2021.02.19.21252115