Laryngitis

Laryngitis is an inflammation of the larynx. The larynx, or voice box, is a part of the respiratory system and contains the vocal cords. In laryngitis, the vocal cords become inflamed or irritated. The swelling distorts the sounds produced by the air passing over them, causing the voice to sound hoarse.

Laryngitis can be either acute or chronic. Laryngitis that persists beyond two or three weeks is classified as chronic.

What is the larynx?

The larynx is made up of muscles and cartilage that are bound together by elastic tissues. The larynx helps us speak and breathe.

Air passes in and out of the larynx with every inhalation and exhalation. The air from the lungs passes over the stretched vocal cords and vibrations are modified by the tongue, palate and lips to create speech.

Laryngitis is an inflammation or irritation of the vocal cords. 

Causes

Acute laryngitis

Acute laryngitis is typically caused by a viral infection. It is more common in adults aged between 18-40 years.

Other causes of laryngitis include:

• Bacterial infection;
• Fungal infection - this tends to be more common in people with compromised immune systems, such as those with HIV or undergoing chemotherapy, and;
• Incorrect use of asthma medication inhalers.

Chronic laryngitis

Laryngitis that persists for more than two or three weeks is considered chronic. Chronic laryngitis is most commonly caused by irritants, such as stomach acid, from conditions such as heartburn.

Other potential causes of chronic laryngitis may include:

• Chronic sinusitis;
• Excessive alcohol use;
• Habitual overuse of the voice, such as by singers or actors;
• Smoking;
• Vocal cord polyps or nodules;
• Inhaled irritants such as allergens or workplace chemicals;
• Cancer;
• Thyroid disease;
• Stroke, and;
• Neurological disorders, commonly associated with Parkinson's disease, motor neurone disease or myasthenia gravis.

Signs and symptoms

The symptoms may vary in severity, according to the underlying cause, but some of the more typical symptoms may include:

• A sore throat;
• Hoarse voice, or absence of voice;
• Mild fever;
• Dry throat with a tickling sensation, and;
• Breathing difficulties (not very common).

If the laryngitis is part of a more widespread infection, other symptoms may be apparent and may include:

• Headache;
• Fatigue;
• Swollen lymph nodes;
• Increased saliva in the mouth;
• Runny nose;
• Painful swallowing, and;
• Generalized aches and pains.

The symptoms of acute laryngitis tend to worsen over two or three days, but then start to ease and resolve within a week or so. The croaky voice may persist for longer than a week, as the inflammation may take some time to settle.

Croup

Croup is a type of laryngitis caused by a viral infection and specifically affects young children, typically up until the age of six years. Croup is associated with swelling and inflammation of the larynx and its surrounding structures, including the trachea and airways to the lung.

Symptoms of croup include:

• A distinctive cough that can sound like a bark;
• Mild fever;
• Noisy breathing, and;
• Breathing difficulties, if the swelling is severe.

Methods for diagnosis

Diagnosis of acute laryngitis is generally straightforward and involves taking a medical history and performing an examination, typically of the ears, nose and throat. Most cases do not require any further testing in order to confirm the diagnosis.

When the laryngitis is chronic, there may be the need for further testing such as a blood test, X-ray and possibly a laryngoscopy to examine the back of the throat. During a laryngoscopy, a thin tube containing a fiber-optic camera is inserted through the nose and down the back of the throat, to see if the vocal cords are inflamed, and to identify any polyps or nodules.

Types of treatment

Acute laryngitis

Acute laryngitis typically resolves on its own without any intervention. Home care may include:

• Drinking lots of fluids;
• Taking over-the-counter pain-relief medications such as ibuprofen or acetaminophen as recommended. They can ease the pain, as well as ease fever and headache;
• Breathing in humidified air, using a humidifier, and;
• Voice rest - refraining from shouting and singing. Quiet conversation is generally OK, but whispering makes the larynx work harder, so is best avoided.

Severe cases of acute laryngitis may involve a short course of steroids such as prednisolone or dexamethasone to decrease the inflammation and speed recovery, but this tends to be limited for use in people with severe laryngitis that causes breathing difficulties.

It is not common to prescribe antibiotics for acute laryngitis, as most cases are caused by a virus. Taking antibiotics when they are not needed contributes to the problem of antibiotic resistance.

Gargles, throat sprays or lozenges are generally ineffective as they will not reach the larynx, and are better used for other cases of sore throat.

Chronic laryngitis

The treatment of chronic laryngitis depends on the underlying cause. Treatment may include:

• Quitting smoking;
• Reducing alcohol consumption;
• Treating the underlying medical condition - for instance, people with heartburn need to make lifestyle changes and take medication to reduce their stomach acid reflux, and;
• Surgical removal of vocal cord nodules or polyps.

Potential complications

• Infection may spread to other parts of the respiratory tract, and;
• In rare cases, it can be associated with severe respiratory distress, which requires urgent medical attention.

Prognosis

Laryngitis that does not have a serious underlying cause is not a serious condition and tends to resolve on its own.

Prevention

You can help to prevent laryngitis by:

• Following good hand hygiene;
• Limiting your exposure to others with upper respiratory tract infections;
• Ensuring your children receive the Haemophilus influenza vaccine;
• Not straining your voice, and;
• Stopping smoking.