Question

A number of chickens on a poultry farm begin to exhibit symptoms of pleuritis. Subsequent lab analysis of the flock indicates 40 ppm levels of ammonia in both symptomatic and asymptomatic birds. Which is the most likely cause of pleuritis in this case?

Answer 1

The presence of high levels of ammonia suggests that hypersensitivity pneumonitis, an allergic reaction to inhaled ammonia from bird droppings, is the most likely cause of pleuritis among the chickens, classifying it as an occupational disease.

Step-by-step explanation:

The most likely cause of pleuritis among the chickens on the poultry farm, given the presence of 40 ppm levels of ammonia, is hypersensitivity pneumonitis (HP), related to an allergic reaction to inhaled substances such as ammonia.

Hypersensitivity pneumonitis is often an occupational or environmental disease that arises when the lungs become inflamed due to an allergic reaction to inhaled allergens like dust, molds, chemicals, or, as in this case, high levels of ammonia from bird droppings. Chlamydial pneumonia could be another possibility, but it's typically associated with organisms other than ammonia. Furthermore, the lab analysis indicates ammonia presence, which is not exclusive to infected birds and may point towards environmental factors as the primary cause. Thus, it's the environmental exposure to ammonia in this scenario rather than an infectious agent that is more likely to have caused the pleuritis, categorizing this condition as an occupational disease.