A common condition seen in ENT clinics in Trivandrum
One of the commonly underdiagnosed clinical conditions encountered in the ENT clinic is LPRD.
Technically, it is an extraesophageal GERD (Gastroesophageal reflux). Other extraesophageal syndromes include cough, reflux laryngitis, and asthma. Upper gastrointestinal endoscopy and pH monitoring which are classically diagnostic of GERD are not of much help in diagnosing LPRD. The erstwhile stalwart of otology in India, Dr Mahadeviah used to comment that LPRD is so common that in any case of chronic cough, a few weeks course of antireflux medicine could do wonders.
Reflux cough syndrome
Chronic cough, defined as cough greater than 3 weeks duration, is a common condition seen by ENT doctors in India. In nonsmoking patients with a normal chest radiograph, not taking angiotension-converting enzyme (ACE) inhibitors, the most common causes of cough include postnasal drip syndrome, asthma, GER, and chronic bronchitis, and these four conditions may account for up to 90% of cases of chronic cough.
The evaluation of patients with chronic cough is not always straightforward, because patients may not have a single underlying cause of their cough, but instead may have several disorders that contribute to symptoms. Nonetheless, evaluation of chronic cough generally begins with the anatomic diagnostic protocol developed by Irwin and colleagues. This protocol evaluates chronic cough patients who have normal chest radiographs and not taking angiotension-converting enzyme inhibitors, for the three most common causes of cough: (1) postnasal drip syndrome, (2) asthma, and (3) GERD. Once the contributions of postnasal drip syndrome and asthma have been assessed, patients can then undergo evaluation for GERD.
The diagnosis of GER-associated chronic cough may be difficult because many patients do not exhibit typical reflux symptoms, and clinicians must maintain a high index of suspicion for the diagnosis. Up to 75% of patients with GER-associated cough do not display classic symptoms of reflux (ie, heartburn and regurgitation). Everett and colleagues found that only 63% of patients studied displayed the classic symptoms of reflux. In contrast to classic symptoms, patients with GER-associated cough may describe a cough that occurs primarily during the day, in the upright position, during phonation, when rising from bed, or cough associated with eating. The process is further complicated by the fact that there is no diagnostic test that is definitive in identifying GER as a cause of chronic cough.
Symptoms associated with reflux cough syndrome include
Cough occurs during day
Cough in upright position
Cough during phonation
Cough when rising from bed
Cough associated with eating