<prompt> Which pattern is seen in pulmonary function tests in a patient with interstitial lung disease?FEV1FVC ratio increases and DLCO increasesFEV1FVC ratio increases and DLCO decreasesFEV1FVC ratio decreases and DLCO decreasesFEV1FVC ratio decreases and DLCO increases  <response>: Pulmonary function tests In PFT,Airway narrowing,lung volume and gas exchange capacity are quantified and compared with normal values adjusted for age,gender,height,etc. Most forms of ILD will show restrictive pattern on PFT. Restrictive deficit TLCTotal lung capacity Reduced FEV1Forced expiratory volume in 1 sec Symmetrically reduced FVCForced vital capacity Reduced DLCODiffusing capacity of the lung for carbon monoxide Reduced FEV1FVC ratio Normal or increased characteristically 0.7 Approach to pulmonary function test interpretation: 