With allergies, expert opinion is nothing to sneeze at

Question: What is asthma?

Answer: Asthma is a chronic inflammatory condition of the lungs. It involves:

A narrowing of air passages that causes wheezing, coughing and shortness of breath.

Excess mucus production in the lungs that can cause a wet, productive cough.

Infiltration of the lining of the lungs with inflammatory cells that cause the air passages to be more sensitive and irritable to allergens, viral infections, cold weather and exercise.

Q: So many studies show that asthma is on the increase in our kids, but there are many reasons bandied about. Can you tell us what might be causing this increase in cases?

A: About 20 million Americans suffer from asthma. Approximately half of asthma cases are caused by allergies ("allergic-asthma"). Asthma is the most common chronic condition among children and accounts for most missed school days.

The prevalence of asthma has been increasing since the early 1980s. Many hypotheses have been proposed for this phenomenon. One that I find very interesting is the hygiene hypothesis. This simply states that a lack of early childhood exposure to bacterial and parasitic infections due to improved hygiene and the overuse of antibiotics shifts our developing immune system toward developing allergic diseases like asthma.

Q: If you suspect your child might have allergies, what should you do?

A: Ask yourself a few questions to help distinguish between the signs and symptoms of allergies and the common cold:

When your child gets a cold, does it seem like it takes much longer for him or her to shake it than other kids? Does the cough linger for weeks?

Does your child frequently sneeze or have itchy and watery eyes?

Does your child always have dark circles under her eyes - even when well rested ("allergic shiners")?

Is your child often rubbing or itching his nose ("allergic salute")?

Q: What's the right age to get your kid tested for allergies?

A: Allergy skin testing is the gold standard for diagnosing allergies, and it can be done on children who are at least 6 months old. The testing becomes more reliable as the child gets older.