[The change in the activity of angiotensin converting enzyme in patients with pneumonia and chronic obstructive pulmonary diseases].

The activity of angiotensin-converting enzyme (ACE) was measured in the serum and bronchial contents of 69 patients with pneumonia and 77 with chronic obstructive pulmonary diseases (COPD). ACE activity was decreased both in the blood and bronchial contents during the acute phase of pneumonia. With resolution of the inflammatory process, ACE activity normalized. In patients with COPD, the activity of ACE is decreased during remission in comparison with the mean values in the population. During COPD exacerbation the activity of ACE increases both in the blood and bronchial contents. Changes in ACE activity in pneumonia and COPD are more pronounced in the bronchial contents than in the blood. Presumably alteration of the enzyme concentration is the only cause of alteration of its activity in patients with COPD and pneumonia.