What is farmer's lung?

Some inhaled allergens provoke IgG rather than IgE antibody responses, perhaps because they are present at relatively high levels in inhaled air. ➢ When a person is reexposed to high doses of such inhaled antigens, immune complexes form in the alveolar wall of the lung. ➢ This leads to the accumulation of fluid, protein, and cells in the alveolar wall, slowing blood-gas interchange and compromising lung function. ➢ This type of reaction occurs in certain occupations such as farming, where there is repeated exposure to mold spores in the dust from moldy hay, straw, or grain As a result, farmers inhale both dust particles and mold spores. ➢ In fact, a farmer can inhale up to 750,000 of these spores per minute!!!