Occupational asthma caused by high-molecular-weight substances.

More than 250 agents that are encountered in the workplace have been shown to induce asthma in susceptible individuals. It is estimated that 2% to 15% of cases of asthma may be occupational. High-molecular-weight substances, such as plant and animal proteins, enzymes, and large carbohydrate molecules, can induce IgE-mediated occupational asthma. The incidence of disease varies among industries and is dependent on the physiochemical properties of the agent, the level and duration of exposure, industrial hygiene, engineering practices, and host factors. Risk factors, common high-molecular-weight workplace antigens, diagnosis, treatment, and prognosis are discussed.

Hereditary angioedema: a rare but potentially lethal disease.

Hereditary angioedema, although uncommon, should be considered in the differential diagnosis of all patients with facial edema. In this article, we present a case of hereditary angioedema and discuss the presentation, diagnosis, and management of the disease.

Fish and shellfish allergy.

Fish and shellfish are important in the American diet and economy. Nearly $27 billion are spent each year in the United States on seafood products. Fish and shellfish are also important causes of food hypersensitivity. In fact, shellfish constitute the number one cause of food allergy in the American adult. During the past decade, much has been learned about allergens in fish and shellfish. The major allergens responsible for cross-reactivity among distinct species of fish and amphibians are parvalbumins. The major shellfish allergen has been identified as tropomyosin. Many new and important potential cross-reacting allergens have been identified within the fish family and between shellfish, arachnids, and insects. Extensive research is currently underway for the development of safer and more effective methods for the diagnosis and management of fish and shellfish hypersensitivity.