A man presented with bilateral crepitations In the base of the lungs and signs of pneumonitis with a history of exposure to pigeon faeces. What is true about this condition?: (A) Diagnosis can be made on the basis of history, (B) CT scan is the investigation of choice, (C) Chest X-ray will reveal characteristics changes, (D) It is a type 1 hypersensetivity reaction
Answer is A. Patient may developed hypersensitive pneumonitis.