WASHINGTON — If a child with what seems to be asthma appears in your waiting room, a skin test for allergies will tell you whether you'll be seeing a lot more of this patient, according to Elena R. Reece, M.D.
However, an even better predictor of chronic asthma is atopy combined with wheezing, she said at a conference sponsored by the Mid-Atlantic Center for Children's Health and the Environment. “The most common cause of wheezing in young children is viral respiratory infection. But the strongest predictor for wheezing that develops into asthma is atopy. About 70%-90% of children with asthma are atopic.”
If the patient also started wheezing early in life, “it's bad” as far as a prognosis is concerned, said Dr. Reece, chief of allergy and clinical immunology at Howard University Hospital, Washington. “The earlier you have the onset of wheezing, the more likely it is to be persistent and severe. Lung function in these children is significantly reduced at age 6.”
There are three different patterns of wheezing in children, she said:
▸ Transient wheezers have reduced lung function after birth with congenitally smaller airways. They start wheezing before 6 months of age but usually stop by 6 years of age, when the lungs are sufficiently grown.
▸ Persistent wheezers, on the other hand, have normal lung function at birth, but function is significantly reduced by age 6 months, Dr. Reece said. “This group has more frequent asthma symptoms during the first year of life.”
▸ Late wheezers begin sometime around their 6th birthday. Lung function in this group, however, is not significantly reduced.
With or without wheezing, making a definitive diagnosis can be tricky because there is no way to objectively measure symptoms in very young children. In general, Dr. Reece said, pediatric asthma patients who start having symptoms early are more likely to have pronounced asthma symptoms, increased use of albuterol, reduced lung function, and markers of atopy.
Consider the possibility of asthma if a child is repeatedly diagnosed with reactive airways disease, recurrent bronchitis, chronic cough, wheezy bronchitis, asthmatic bronchitis, or recurrent bronchiolitis.