Laryngopharyngeal reflux

Laryngopharyngeal reflux is also known as LPR for short.

The difference between acid reflux as it normally occurs and LPR is that the gastric contents reach the upper part of the esophagus causing symptoms such as asthma (maybe), hoarseness, coughing, sore throat, possibly even dental erosion.

Strangely enough, heartburn is a symptom in fewer than half the people who have laryngopharyngeal reflux. That’s probably why it’s also called “atypical reflux”.

GERD has been recognized as a problem involving acid reflux since the 1930s. But the influence of stomach acid on the larynx was only really recognized in 1968, and the link between respiratory conditions and acid reflux was only acknowledged in 1979.

The good news is that even though the condition was slow to be recognized, treatment can be very effective, and the treatment of LPR reflux disease eliminates LPR symptoms in the airways and lungs.

By comparison with people who have GERD, where heartburn is the chief symptom, laryngopharyngeal reflux produces symptoms higher up the esophagus or in the larynx or pharynx.

Symptoms of Laryngopharyngeal Reflux?

Other symptoms of laryngopharyngeal reflux include post nasal drip, difficulty swallowing, wheezing, globus pharyngis, and constant throat clearing. Heartburn is not a symptom in the majority of cases.

We assume this is because the stomach acid contents simply don’t stay in the esophagus for long enough to cause damage, but they reach the much more sensitive tissues of the throat, producing perhaps a burning sensation, spasm, or difficulty in breathing. It’s been reported that the sensations are most acute in the early morning just after waking from sleep.

Unfortunately diagnosis of laryngopharyngeal reflux is rather difficult because of the wide range of symptoms which may be displayed, and the fact that there are a number of other causes for these symptoms.

One of the diagnostic tools that tends to be used is the administration of acid suppression drugs: if this results in reduction of symptoms, the implicit diagnosis is LPR. However, some scientific studies have emphasized that it’s important to measure the level of acidity in the pharynx to be absolutely sure of the cause of the symptoms.

Management of the condition tends to involve weight loss and diet changes, together with proton pump inhibitors. Although effective in the majority of cases of GERD, they are sometimes not as effective in treating LPR.

It is important, however, to treat this condition because there are some serious complications which includes laryngeal granulomas, laryngospasm, laryngeal granulomas, subglottic/glottic stenosis, and even (fortunately rarely) laryngeal carcinoma.

Diagnosis

To emphasize the difference between the conditions we can look at the diagnostic criteria using pH monitoring.

A diagnosis of GERD would be made if somebody experiences more than 45 episodes of reflux per day, or has prolonged exposure to acidic stomach material in the lower esophagus. (Some exposure is normal, and occurs during belching.)

However, only one or two episodes of reflux that reaches a pH of below 4 in the upper esophagus is regarded as characteristic of LPR. It’s only true that some variation between different medical facilities in these diagnostic criteria, but the theme is always the same: laryngeal and pharyngeal mucosa are much more easily damaged by acidic stomach contents than the esophagus.

So we can conclude that LPR and GERD are two separate and distinct conditions, and the question therefore is whether they should be treated differently.

Certainly the way the esophagus functions appears to be different in the two conditions. Clearance of acid from the esophagus takes a much longer time in individuals who have GERD than it does in those with LPR. Furthermore, the motility of the esophagus is quite different between the two groups, and so is the pattern of reflux, since LPR patients are much more prone to reflux while standing and GERD patients are much more prone to reflux when lying down.

Assuming that medical investigation, which may include pressure testing and pH probe testing, reveals a clear diagnosis, what is to be done?

Treatment

There’s a difference in the way that patients with LPR and GERD respond to anti-acid medication. Proton pump inhibitor (PPI) therapy must be much more intense for LPR patients than for GERD patients, in whom the administration of PPI therapy often results in rapid improvement in symptoms.

Furthermore, a report from Reavis and colleagues indicated that people with LPR are much more at risk of esophageal dysplasia than those with GERD, so effective treatment is actually really important.

What Causes This Kind Of Acid Reflux?

The problem is there’s not a lot of information about the etiology and causation of laryngopharyngeal reflux. Obesity is not a factor; and individuals with LPR often have apparently normal motility of the esophagus; furthermore, LPR often occurs when people standing; and the reflux events tend to be rather brief compared to the prolonged ones that are symptomatic of GERD.

All of this raises a number of interesting questions. The damage to the larynx characteristic of LPR is caused by both acid and activated pepsin. This damage is often irreversible. Regrettably, however, the etiology of events that cause LPR are largely unknown.

The most likely hypothesis is currently that there is a dysfunction of the upper esophageal sphincter. The most common symptoms found during investigation are simply those of chronic inflammation; serious changes such as ulcerative disease or cancer are much rarer.

One of the most unpleasant (and dangerous) symptoms of LPR is paroxysmal laryngospasm. You can read more about this here.

Treatment

As mentioned above, treatment for LPR and GERD are different. It turns out that the resistance of the esophagus to acid damage is considerable, apparently being able to tolerate up to 50 acid reflux episodes every single day without injury; by contrast, it appears that only three episodes of exposure of the larynx to acid and pepsin can produce injury; this means that chronic therapy is probably the answer for LPR.

A daily dose of PPI, which inhibits the final stage of acid production, can be effective in controlling stomach acid but the effects tend to last for only 14 hours. With LPR it’s therefore necessary to take another dose in the evening to ensure that the laryngeal mucosa receives 24 hour protection.

As and adjunct to medication, counseling on lifestyle and diet changes is usually appropriate. In younger patients who have very severe LPR, Nissen fundoplication surgery may be the treatment choice.

* Reavis KM, Morris CD, Gopal DV, Hunter JG, Jobe BA. Laryngopharyngeal reflux symptoms better predict the presence of esophageal adenocarcinoma than typical gastroesophageal reflux symptoms. Ann Surg 2004;239(6):849–856; discussion 856–858.