Work-related asthma.

Work-related asthma accounts for at least 10 percent of all cases of adult asthma. Work-related asthma includes work aggravation of preexisting asthma and new-onset asthma induced by occupational exposure. Occupational exposure to very high concentrations of an irritant substance can produce reactive airway dysfunction syndrome, while exposure to allergenic substances can result in allergic occupational asthma. An important step in the diagnosis of work-related asthma is recognition by the physician of the work relatedness of the illness. A thorough history can elucidate the work relation and etiology. Objective tests, including pulmonary function, nonspecific and specific bronchial hyperresponsiveness, serial peak expiratory flow rates, and skin allergies, should be performed to confirm the diagnosis of asthma and demonstrate a work correlation. Treatment for occupational asthma--use of anti-inflammatory medications such as inhaled steroids and bronchodilators--is the same as that for nonoccupational asthma. Prevention is an integral part of good medical management. In patients with work-aggravated or irritant-induced asthma, reduction of exposure to aggravating factors is essential. In patients with allergic occupational asthma, exposure should be eliminated because exposure to even minute concentrations of the offending agent can trigger a potentially fatal allergic reaction.