Final answer:
The improvement in FEV1/FVC ratio from 60% to 68% after bronchodilator administration indicates a moderately reversible obstructive lung disease. The correct diagnosis, based on the data provided, would be option B) Moderately reversible obstructive lung disease.
Step-by-step explanation:
When assessing pulmonary function, a key diagnostic tool is spirometry, which measures the rate of air expulsion from the lungs to diagnose restrictive or obstructive lung disease. The ratio of forced expiratory volume in one second (FEV1) to the forced vital capacity (FVC) differentiates between these two conditions. A patient with obstructive lung disease has a reduced FEV1/FVC ratio due to obstruction in the airways that results in slow exhalation.
In the scenario provided, the patient has an FEV1/FVC ratio that improves from 60% to 68% after a bronchodilator (BD) is administered. This indicates that there is some reversibility to the obstruction in the airways. According to guideline-based categorization, an increase between 12% to 20% and by 200 mL in FEV1 post-bronchodilator indicates a moderately reversible obstructive lung disease, such as asthma where airway obstruction can be partially relieved by medication.
Therefore, the correct option is B) Moderately reversible obstructive lung disease. It's essential to correctly diagnose the severity of the reversibility in order to tailor effective treatment plans for respiratory conditions like asthma or chronic obstructive pulmonary disease (COPD).