Postnasal drip syndrome. Two hundred years of controversy between UK and USA.

This review discusses the trans-Atlantic controversy concerning Post Nasal Drip Syndrome (PNDS). PNDS was described as a common condition in the UK in the nineteenth century and was so extraordinarily prevalent in the USA that it was called 'American catarrh'. American chest physicians adopted PNDS as the most common cause of chronic cough. A relationship between PNDS and chronic cough was not accepted by UK chest physicians, who preferred to use the term 'rhinosinusitis' instead of PNDS. In the USA the diagnosis of PNDS was linked to a response to therapy with a sedating antihistamine and decongestant, but UK physicians doubted if this was a specific therapy and did not accept the therapy as diagnostic for PNDS. In 2006 the American College of Chest Physicians replaced the term PNDS with upper airway cough syndrome and some UK otolaryngologists proposed that PNDS should be replaced with rhinosinusitis. PNDS is now being replaced with more general descriptions of upper airway disease and a causal link with chronic cough is now disputed. PNDS may be caused by a mucus hypersecretory phenotype that develops following chronic exposure of the respiratory tract to particulate matter, allergens, irritants and pathogens. Current research on treating excessive airway mucus in the lower airways may be applicable to PNDS.