the diffusion capacity of lung (DL) is decreased in all of the following conditions except

Ans. is 'b' i.e., Goodpasture's syndrome Gas diffusion tests : Gas diffusion tests measure the amount of oxygen and other gases that cross the alveoli into the blood. These tests evaluate how well gases are being absorbed into the blood from lungs. Gas diffusion tests include. Carbon monoxide diffusing capacity (transfer factor DLcy) Aerial blood gases Carbon monoxide diffusing capacity (DL): This measures how well the lung transfers a small amount of carbon monoxide into the blood0. Normally, in the lung, a gas has to cross the alveolar membrane, capillary membrane to reach the blood where it combines with hemoglobin. So quiet obviously the diffusion capacity of gas depends upon Driving pressure of the gas Surface area of alveolar capillary membrane Thickness of alveolar capillary membrane Diffusion coefficient of the gas Red blood cell volume. Reaction rate with hemoglobin and hemoglobin level of patient. Degree of V/Q mismatching.