Croup is a condition that causes an inflammation of the upper airways — the voice box (larynx) and windpipe (trachea). It often leads to a barking cough or hoarseness, especially when a child cries.
Most cases of croup are caused by viruses. Those involved are usually parainfluenza virus (which accounts for most cases), adenovirus, and respiratory syncytial virus (RSV). Croup is most common — and symptoms are most severe — in children 6 months to 3 years old, but can affect older kids, too.
Most cases of viral croup are mild and can be treated at home, though rarely it can be severe and even life-threatening. Some children are more prone to developing croup when they get a viral upper respiratory infection.
The term spasmodic croup refers to a type of croup that develops quickly and may happen in a child with a mild cold. The barking cough usually begins at night and is not accompanied by fever. Spasmodic croup has a tendency to come back again (recur).
Symptoms are treated the same for either form of croup.
Signs and Symptoms
At first, a child may have cold symptoms, like a stuffy or runny nose and a fever. As the upper airway (the lining of the windpipe and the voice box) becomes progressively inflamed and swollen, the child may become hoarse, with a harsh, barking cough. This loud cough, which is characteristic of croup, often sounds like the barking of a seal.
If the upper airway becomes increasingly swollen, it becomes even more difficult for a child to breathe, and you may hear a high-pitched or squeaking noise when a child inhales (this is called stridor). A child also may tend to breathe very fast and might have retractions (when the skin between the ribs pulls in during breathing). In the most serious cases, a child may appear pale or have a bluish tinge around the mouth due to a lack of oxygen.
Symptoms of croup are often worse at night and when children are upset or crying. Besides the effects on the upper airway, the viruses that cause croup can cause inflammation farther down the airway and affect the bronchi (large breathing tubes that connect to the windpipe).
