I saw an emergency room nurse in my clinic for a cough that was not going away. I listened to the story, examined her and said that I thought she had croup. I gave her instructions and sent her out.

I ran into her a few weeks later. She grinned at me. "I thought you were completely full of it when you said I had croup. But nothing else was working, so I followed your instructions. I was so much better the next day that I decided that you were right after all."

I grinned back. "Kind of embarassing to have one of those little kid illnesses, right?"

I have seen two cases of croup in the last week. In adults, not children. They look surprised when I say that I think they have croup, but it looks different in adults than children.

Croup is a viral illness also known as acute laryngotracheitis, or tracheobronchitis. The virus inflames the back of the throat and down the trachea, inflames the vocal cords and sometimes the bronchi as well. This is an upper airway illness, as opposed to a lower airway illness. Lower airway would be things like pneumonia, influenza or an asthma exacerbation.

Small children have a narrower airway than adults. They can get a terrifying barking cough. Some really do sound like a seal barking. Cold air and humidity help to soothe and reduce the swelling, so the classic winter emergency room visit is the parent saying, "She has this horrible cough but she coughed less once we got her in the car." For small children, we often use a one time dose of steroids to reduce the inflammation and swelling. If the swelling is worrisome, we hospitalize them and put them in a cold air mist tent, with oxygen if needed.

This is not epiglottitis, which is a bacterial infection of the epiglottis. The airway can completely close off and suffocate a child. We intubate and give iv antibiotics. The child looks very ill, sits up and forward, drools because they can't breathe well enough to swallow. Call an ambulance immediately.

The oldest person I have seen with a barking cough is a 9 year old. Mostly the barking cough is in children under two. Older children and adults get laryngitis or are hoarse, and they cough a lot.

The clinical picture in people over two is hoarseness, a cough that doesn't respond very much to cough medicine or inhalers such as albuterol (both of which work more on lower airways), fever the first couple days or not at all, a mild but not severe sore throat and mild or no nasal congestion. One patient this week said, "It feels all hot from the back of my nose down into my chest."

Strep throat can cause vocal changes, but it's the "talking with mashed potatoes in your mouth" voice, not laryngitis. The larynx is usually not inflamed in strep. It is the enlarged tonsils that make the voice funny in strep, and usually adults don't have that. Also, the throat hurts more in strep, little or no congestion, more fever, that rare but distinctive rash, headache and often stomach ache.

I am always hopeful that my patient is up to date on their diptheria vaccine, too. I have not seen diptheria and don't want to.

Croup is a virus, so antibiotics do not help. For adults, the treatment is similar to children.
1. Humidified air. Steam up the shower before bed, or put a bowl of very hot water on a table, put your head over it and a towel over you and the bowl, to hold in the steam. Hot air humidifiers tend to breed bacteria very efficiently, so I don't recommend them.
2. Cold air. Turn down the thermostat, crack the window.
3. Rest your voice. Stop talking. Really.
4. Rest and recuperate. Let your immune system work on the virus instead of you running around like a crazy person.

Adults are often somewhat miffed when they are told that they have croup and to treat it with cold air, humidity and not talking. It seems too simple and a bit silly. But you did want to get better, didn't you? Call it laryngotracheitis instead, that sounds a lot more grown up.

for Science Quest 2012