What is extrinsic allergic alveolitis?
The term extrinsic allergic alveolitis (EAA) refers to a group of lung diseases resulting from exposure to dusts of animal and vegetable origin. The name, although complicated, describes the origin and the nature of these diseases. • “extrinsic”– cause originating outside the body • “allergic”– caused by the allergic reaction of the body to a specific substance or condition • “alveolitis”– an inflammation in the inner part of the lungs (alveoli – small air sacs in the lungs) What causes extrinsic allergic alveolitis? Intense or prolonged exposure to animal or vegetable dusts can result in extrinsic allergic alveolitis. The dust particles must be 5 microns or smaller to get into the alveoli. Animal and vegetable dusts are complex mixtures originating from many different sources such as husks, bark, wood, animal dander, and microorganisms including bacteria and fungi. The microorganisms produce toxic chemicals that form part of the mixture. Insects and insect fragments, bird droppings
