ZT: croup (义膜性喉炎)

What is croup?
Croup is a swelling of the voice box (larynx) and windpipe (trachea). Croup can be caused by allergies, bacteria, or inhaled irritants, but usually it's the result of a virus.

Most of the time, the culprit is the parainfluenza virus, but other viruses — respiratory syncytial virus (RSV), adenovirus, influenza, and measles, for example — can also trigger croup.

Croup is most common in children between the ages of 6 months and 3 years, although a child can get croup at any age. The illness shows up most frequently between the months of October and March. Most cases of croup today are not serious, but a severe case can require hospitalization.


What are the symptoms of croup?
Because croup swells the throat and voice box, it alters the sound of your toddler's cough (and voice). If your child has a very hoarse, deep cough that sounds like a barking seal, it's probably croup. In fact, this cough is so distinctive that your doctor can probably tell you whether it's croup just by listening to your child over the phone.

Croup often appears after several days of cold symptoms and usually worsens at night. As it continues, your toddler may have labored breathing or stridor, a high-pitched squawking or crowing noise when he inhales. He may also run a low fever.

Croup is often worst the first two or three nights, and it usually goes away in a week or so.

Is croup dangerous?
Not as dangerous as it once was. Today, the vaccines for measles, Haemophilus influenzae (Hib), and diphtheria protect children against some of the more dangerous forms of croup.

Your toddler's croup will probably go away within a week without any problems. If he has a severe case of croup, however, it can lead to serious breathing difficulties.

When should I call the doctor?
Call the doctor right away if you suspect that your toddler has croup. She'll probably ask you specific questions about your child's cough and breathing, so keep him nearby during your conversation.

If your toddler has labored breathing or stridor when he's resting, take him to the hospital. While these symptoms can be part and parcel of a coughing fit, their appearance when your toddler's resting may mean that he has serious, potentially life-threatening swelling in his throat.

Of course, if your child seems to be struggling for breath and drooling, or his lips or skin are turning blue, call 911 right away.

How do you treat croup?
If this is your toddler's first bout with croup and the doctor determines that he has a mild case, you should be able to treat him at home.

Moist or cold air seem to help reduce the swelling of the airways, so the standard course of action is to take your child into a steamy bathroom for 15 to 20 minutes (turn on the hot water in the shower or bathtub and close the bathroom door) or out into the cold night air. Holding him upright will help him breathe more easily.

The steamy bathroom treatment may help, but it won't make the cough to go away completely. You may have to repeat the routine each time your child wakes up coughing throughout the night.

You might also try using a cool-mist humidifier in your child's room to maintain a humid environment. (Be sure to clean the humidifier daily with a bleach-and-water solution to ward off the growth of mold or bacteria.) Also make sure your toddler is getting plenty of fluids.

You may want to give your child the appropriate dose of acetaminophen or ibuprofen for his fever. (Never give your child aspirin, which can trigger a rare but potentially fatal disease caused Reye's syndrome in children with a virus.)

Since a virus is probably the culprit, antibiotics won't help. Don't give your child cough medicine, either. It won't have any effect on the swelling in his throat, and it can make it harder for your toddler to cough up mucus.

If the steamy bathroom and cold air techniques don't provide any relief, the doctor may prescribe oral steroids to reduce the swelling and help your child breathe more easily. Oral steroids were previously used mostly for children with moderate or severe croup, but recent research suggests they may be worthwhile even in milder cases.

If your toddler has a severe case of croup that requires hospitalization, he may be given oxygen, a medication to inhale, or steroids to help reduce the swelling of his airways. He may also be given intravenous fluids to combat dehydration.

Can my child get croup again?
Yes. In fact, some children seem to be more prone to getting croup than others until their airways grow bigger. If your child gets croup a second time, try the at-home therapy right away. And don't hesitate to call your doctor. Each croup episode can be different, some more serious or needing more aggressive treatment than others.

Is croup contagious?
Yes. Unless your toddler's croup is the result of allergies or irritants, the virus that's causing it is contagious, so keep him home until he's free of symptoms