What looks like asthma may not be . . . asthma

October 4, 2007

Just because a patient presents with the classic signs and symptoms of asthma is no reason to rule out inhaled corticosteroids, albuterol and the rest of the asthma armamentarium. The first step is to be sure that what looks like asthma really is asthma.

Just because a patient presents with the classic signs and symptoms of asthma is no reason torule out inhaled corticosteroids, albuterol and the rest of the asthma armamentarium. The first stepis to be sure that what looks like asthma really is asthma.

"A trial of therapy is not the way to determine asthma and it usually won't work anyway,"cautioned Alan Kaplan, MD, chair of the Family Physicians Airways Group of Canada. "You needobjective lung function testing to establish asthma. Throwing drugs at what looks like asthma doesnot work because you don't know what is wrong. There are too many other (conditions) it couldbe."

The list of conditions that can mimic asthma is long. Asthma-like wheezing and coughing couldbe something as complex as a weakened immune system and as difficult to identify as a polyp impingingon an airway or partially blocking a sinus cavity. Cystic fibrosis can mimic asthma, as can the earlystages of pertussis, tuberculosis, vocal cord dysfunction, sinusitis, rhinitis linked to occupationalexposures, gastroesophageal reflux disease, familiar allergies, panic attacks, hyperventilation, andconditions, such as immotile cilia syndrome in which the airway cilia are immobile and phlegmaccumulates in the airway.

"What looks like asthma may not be asthma," DrKaplan said during the American Academy ofFamily Physicians 2007 Scientific Assembly on Thursday in Chicago. "The key to making an accuratediagnosis is just thinking about it. If you don't consider allergies or the other possibilities, itbecomes quite difficult to make a differential diagnosis."

Familiar lung function and sputum tests remain the mainstay of asthma diagnosis. But thedetective work does not stop once asthma has been positively diagnosed.

"The first step in treatment is to look at the patient's environment, not to pull out yourprescription pad," DrKaplan said.

Many cases of asthma are linked to or developed from allergies. Removing the allergen may beenough to bring breathing symptoms under control.

If medication is needed, he continued, so is education. Most patients-and many physicians-donot know how to use an inhaler properly. It is not uncommon, for example, to find patients withpoorly controlled asthma using inhaled corticosteroids as prescribed but receiving no medication,because no one told them to remove an internal cap that seals the inhaler.

Inhaler use is also a clue to the patient's condition. The physician should quiz the patienton waking at night due to symptoms, any urgent care visits due to breathing problems, an increasedneed for short-acting beta agonist, and refilling more than one canister of a short-acting betaagonist in a month.

"People think nothing of refilling that short-acting beta agonist like it was albuterol," hesaid. "But if you count the doses, exhausting a canister in a month or less is a sure indicator ofpoor control. It's time to step up therapy."

Asthma is almost always treated in stepwise fashion," DrKaplan said. Treatment is stepped upwith higher doses and new drugs until control is achieved. Once symptoms are under control,medications are stepped down with monitoring at each step. The goal is to achieve maximum controlwith minimum medication use.

A major aspect of asthma control for many patients is treating allergic rhinitis. Eliminatingrhinitis can significantly reduce airway responsiveness for many patients, DrKaplan said. Between 5%and 50% of global populations have allergic rhinitis and between 40% and 50% of allergic rhinitispatients also have asthma. Between 30% and 80% of asthma patients also have allergic rhinitis.

"These two conditions are married in many people," he said. "Treating one can improve theother."

The high incidence of allergic rhinitis can also be a revenue source for some familyphysicians. Allergy testing is a very easy-to-learn procedure, DrKaplan explained. In areas wherethere is no allergist available, many family physicians have developed busy and well-reimbursedtesting services.