Reflux Laryngitis (Voice Box Larynx Acid Irritation)
What is reflux laryngitis?
Reflux laryngitis is irritation and inflammation of the larynx due to stomach acid. It is a consequence of GERD (gastroesophageal reflux disease) where the acidic stomach contents spill into the esophagus (food pipe) and rise as high up as the throat. Initially it may cause some irritation of the larynx but over time, the recurrent exposure to acid can significantly damage the vocal cords and other structures in the larynx. GERD is a common condition but not every case will involve the larynx and throat – a condition known as laryngopharyngeal reflux (LPR). If GERD is well managed, it is unlikely that laryngeal and pharyngeal (throat) complications will ever arise.
Reflux Laryngitis Incidence
The exact incidence of reflux laryngitis is difficult to estimate. Many cases may be silent (asymptomatic) and in other instances patients do not seek specialist medical care for the condition and it often remains undetected until symptoms are severe. However, it is known that reflux laryngitis is overall not as common as GERD (gastroesophageal reflux disease). As one of the most common conditions to affect the adult population, about half of all adults will experience GERD occasionally and up to 20% of these patients have chronic reflux. Reflux laryngitis affects only a small number of these GERD patients.
Reflux Laryngitis Pathophysiology
Lower esophageal sphincter
Movement of food through the junction between the stomach and esophagus is controlled by the lower esophageal sphincter (LES). This opens as food is passing down the esophagus thereby allowing it to enter the stomach. It otherwise remains tightly closed to ensure that gastric contents (food, fluid, stomach acid and enzymes) cannot pass backwards from the stomach into the esophagus. In GERD (gastroesophageal reflux disease) the valve is either temporarily or permanently dysfunctional allowing stomach acid and the other contents to flow backwards into the esophagus.
Acid reflux
Since the esophagus cannot withstand the highly corrosive acid, it causes irritation and inflammation of the esophageal walls. This is experienced as the sensation of heartburn. Although GERD is a common condition, a large number of patients never experience any symptoms. In severe cases the stomach acid can pass high up into the esophagus, and even spill out of the esophagus into the throat (pharynx) and voice box (larynx). Inflammation of these areas due to the action of stomach acid is known as reflux pharyngitis and reflux laryngitis respectively.
Laryngopharyngeal reflux
The larynx is the passage between the throat and the airways – trachea, bronchi and then to the lungs. The entire airway is highly sensitive to irritants and the presence of the stomach acid may immediately cause a reaction. If it is not cleared out of the larynx, both the stomach acid and the activated stomach enzyme pepsin will damage the tissue lining the airway. It can destroy the tiny hairs in the lining of the respiratory tract known as the cilia. Mucus in the airways can therefore not be moved out of the tract carrying with it dust, dirt and microbes that are trapped within.
This process is further complicated by the a possible reaction of the pulmonary irritant receptors. Usually these receptors are a line of defense when dust and gases enter the airways and send signals back to the brain which then elicits coughing. The presence of the acidic stomach contents and mucus that collects within the tract can also trigger these receptors. Incoming nerve signals to the walls of the airways causes coughing and narrowing (bronchoconstriction). This hampers air flow through the airways and can exacerbate any pre-existing respiratory conditions.
Reflux Laryngitis Causes
Reflux laryngitis is caused by the stomach contents entering into the larynx. The acid :
- Damages the lining of the airways
- Reduces mucus clearance from the airways
- Irritates the throat thereby stimulating the cough reflex and a constant need to clear the throat
This irritation, injury and damage to the larynx and surrounding part of the airway is the reason for the symptoms of reflux laryngitis. However, it is important to consider the cause of gastroesophageal reflux disease (GERD).
Gastroesophageal Reflux Disease
Acute acid reflux happens occasionally in life with overeating, excessive alcohol consumption and vigorous physical activity immediately after eating a large meal. It often passes on its own and is unlikely to recur. These acute occurrences are still known as gastroesophageal reflux disease (GERD), but GERD is more often thought of as a chronic condition. In this instance a person experiences episodes of acid reflux on a regular basis, and sometimes even daily. However, many of these episodes are asymptomatic and a person may never experience any symptoms despite the backward flow of stomach acid.
The main cause of gastroesophageal reflux disease is lower esophageal sphincter (LES) dysfunction. The exact reason why this sphincter becomes dysfunctional is not always clear. It appears that the muscles become weakened and therefore cannot close the opening as tightly. It may also stem from a problem with the nerves supplying these problems. Other possible causes include :
- Increased pressure within the abdomen (intra-abdominal pressure)
- Hiatal hernia where a portion of the stomach slips into the chest cavity
- Delayed gastric emptying where the stomach does not empty fast enough
- Defective esophageal peristalsis that does not pushed the leak stomach contents back into the stomach
Reflux Laryngitis Symptoms
The symptoms of reflux laryngitis often overlaps with pharyngitis. Therefore it should be considered collectively. The main symptoms include :
Pain and Discomfort
There is usually a sore throat sensation. It is typically worse in the morning upon waking as GERD exacerbates at night. Sometimes the symptoms of the sore throat gradually eases during the course of the day and recurs again after sleep. The soreness may be worse when swallowing. Another common sensation is globus hystericus where a person feels a “ball” or “lump” in the throat despite there being no lump at the site.
Voice and Throat Irritation
Apart from the pain and discomfort, as well as the sensation of a lump in the throat, there are other symptoms associated with irritation and inflammation of the voice and throat. The most notable of these is hoarseness of the voice as the acid reaches the vocal cords. There is a sensation of needing to constantly clear the the throat similar to post nasal drip. These symptoms are usually worse in cigarette smokers and in people who overuse their voice.
Swallowing problems
There may be difficulty swallowing (dysphagia), pain or discomfort when swallowing (odynophagia) and sometimes even gagging with irritation of the throat as a result of reflux. Most of these swallowing symptoms will subside with proper management of GERD. However, should the disease be prolonged then lesions may form that have to be treated separately even once the GERD is brought under control.
Reflux Laryngitis Diagnosis
The effects of GERD on the larynx and pharynx (throat) can be seen in certain diagnostic investigations. However, this is not conclusive for reflux laryngitis as the regular ingestion of corrosive substances can have similar effects. The combination of symptoms over a period of time, response to acid-suppressing medication in conjunction with the findings of diagnostic investigation will collectively point to the diagnosis of reflux laryngitis. These diagnostic investigations include :
- Barium esophagography
- Laryngoscopy
- Endoscopy
- Esophageal pH
Reflux Laryngitis Complications
The supraesophageal effects (effects above the esophagus) of GERD may include :
- chronic voice hoarseness
- chronic throat clearing
- vocal cord growths
- erosive esophagitis
- asthma
- sinusitis
Reflux Laryngitis Treatment
Reflux laryngitis needs to be treated at the root – GERD. The medical treatment of GERD may be needed for a short period of time or is used as chronic medication. Surgery is only considered when medication fails to yield the desired results.
Medication
There are three main medication that is used for gastroesophageal reflux disease.
- Histamine receptor blockers (H2 antagonists)
- Proton pump inhibitors (PPIs)
- Prokinetic agents
Lifestyle
Lifestyle changes are an essential component of treating and managing GERD, and therefore reflux laryngitis.
- Eat several small meals rather than few large meals.
- Avoid heavy meals before bedtime and do not eat at least three hours prior.
- Caffeine, chocolate and alcohol are known triggers and should be used in moderation.
- Cigarette smoking should be stopped as it exacerbates both GERD and reflux laryngitis.
- Weight loss is helpful in reducing the severity of GERD in patients who are overweight or obese.
- Certain foods are known triggers, like spicy foods, but other items may be an irritant to only certain individuals. These foods should be identified and avoided.
- Elevate the head of the bed when sleeping.
References :
http://emedicine.medscape.com/article/864864-overview