COMBINED AMBULATORY ESOPHAGEAL MANOMETRY AND DUAL-PROBE PH-METRY IN EVALUATION OF PATIENTS WITH CHRONIC UNEXPLAINED COUGH

Fifteen consecutive patients referred because of suspicion that gastro esophageal reflux was the cause of their chronic, unlocalised cough un derwent combined ambulatory esophageal manometry and pH-metry in order to correlate cough episodes with gastroesophageal and gastrohypophary ngeal acid reflux. Cough episodes, which were recognized manometricall y as phasic bursts of brief simultaneous elevations in all intraesopha geal pressure leads, were markedly underreported by patients. If all c ough events were considered, that is, single coughs plus ''bursts'' of coughing, patients reported on average 10% of the total manometricall y recorded coughs, whereas if only cough bursts were considered, patie nts reported an average of 23%. Gastrohypopharyngeal acid reflux prece ded 1% and 1.8%, whereas gastroesophageal reflux preceded 9% and 13%, of the total coughs and cough bursts, respectively. One percent and 1. 6% of total coughs and cough bursts, respectively, appeared to precipi tate reflux. Gastrohypopharyngeal reflux events were rare, with only 1 5 episodes recorded in nine of the 15 patients. In 13 asymptomatic vol unteers, no episodes of gastrohypopharyngeal acid reflux were recorded . This study suggests that ambulatory esophageal manometry/pH-metry, p rovides an objective measure of temporal relationships between cough e pisodes and acid reflux events that is superior to relying on the pati ents' reporting of cough episodes. In this study population, the incid ence of a direct temporal correlation between reflux and cough episode s was relatively low. However, a high proportion of patients had gastr ohypopharyngeal reflux, suggesting that acid reflux to the laryngeal i nlet may indirectly play a role in chronic unexplained cough.