Laryngitis Health Article

Definition

Laryngitis is caused by inflammation of the larynx, often resulting in a temporary loss of voice.

Description

When air is breathed in, it passes through the nose and the nasopharynx or through the mouth and the oropharynx. These are both connected to the larynx, a tube made of cartilage. The vocal cords, responsible for setting up the vibrations necessary for speech, are located within the larynx.

The air continues down the larynx to the trachea. The trachea then splits into two branches, the left and right bronchi (bronchial tubes). These bronchi branch into smaller air tubes that run within the lungs, leading to the small air sacs of the lungs (alveoli).

Either food, liquid, or air may be taken in through the mouth. While air goes into the larynx and the respiratory system, food and liquid are directed into the tube leading to the stomach, the esophagus. Because food or liquid in the bronchial tubes or lungs could cause a blockage or lead to an infection, the airway must be protected. The epiglottis is a leaf-like piece of cartilage extending upwards from the larynx. The epiglottis can close down over the larynx when someone is eating or drinking, preventing these substances from entering the airway.

In laryngitis, the tissues below the level of the epiglottis are swollen and inflamed. This causes swelling around the area of the vocal cords and they can't vibrate normally. Hoarse sounds or loss of voice are characteristic of laryngitis. Laryngitis is a very common problem, and often occurs during an upper respiratory tract infection (cold).

Causes & symptoms

Laryngitis is primarily caused by overuse of the voice, a condition faced by people ranging from teachers to performers. Other causes of laryngitis include:

• strain on the larynx from talking or singing for long periods
• shouting or cheering for an extended time
• allergies
• colds or cough
• smoking
• alcohol consumption
• atmospheric conditions like dust in the air
• anxiety
• underactive thyroid
• growths on the larynx

However, the primary medical cause of laryngitis is a viral infection. The same viruses that cause the majority of simple colds are responsible for laryngitis. In extremely rare cases, more harmful bacteria or the bacteria that causes tuberculosis (TB) may cause laryngitis. In people with faulty immune systems (like AIDS patients), infections with fungi may be responsible for laryngitis.

Symptoms usually begin with a cold. The person may have a sore, scratchy throat, as well as a fever, runny nose, aches, and fatigue. Difficulty swallowing sometimes occurs, and the patient may have a ticklish cough or wheeze. Most characteristically, the patient suffers voice loss or the voice will sound strained, hoarse, and raspy.

In extremely rare cases, the swelling of the larynx may cause symptoms of airway obstruction. This is more common in infants because the diameter of their airways is so small. In that case, the baby may have a greatly increased respiratory rate and exhibit loud, high-pitched sounds with breathing (called stridor).

Diagnosis

Laryngitis is easily recognizable. People realize they can't speak or that their voices are hoarse. In most cases, they know the cause. Laryngitis could be the next phase of the flu or the result of cheering too energetically during a football game. In addition to being an easily recognizable condition, laryngitis is a self-limiting condition that goes away on its own. In most cases, laryngitis can be treated at home.

However, a doctor should be consulted if the laryngitis occurs for no apparent reason or if hoarseness lasts for more than two weeks. A doctor may diagnose another condition such as an underactive thyroid. Symptoms of underactive thyroid include tiredness, constipation, aches, and dry skin.

Diagnosis is usually made by learning the history of a cold that is followed by hoarseness. The throat usually appears red and somewhat swollen. Listening to the chest, neck, and back with a stethoscope (an instrument used to hear heart and lungs sounds) may reveal some harsh wheezing sounds when the person breathes.

With chronic laryngitis, TB may be suspected. Using an instrument called a laryngoscope, a doctor can examine the airway for redness, swelling, small bumps of tissue called nodules, and irritated pits in the tissue called ulcerations. Special skin testing (TB testing) will reveal if the person has been exposed to TB.