[Clinical studies on hospital acquired pneumonia in the elderly].

We compared hospital acquired pneumonia (HAP) with nursing home acquired pneumonia in the elderly. There were no differences in the underlying diseases, clinical signs and symptoms between HAP and nursing home acquired pneumonia, but activities of daily living were poor in HAP than nursing home acquired pneumonia. By the bacterial studies from Transtracheal aspiration (TTA), S. aureus, K. pneumoniae, P. aeruginosa and anaerobes were more isolated in HAP. On the other hand, S. pneumoniae and H. influenzae were isolated more in the nursing home acquired pneumonia. In the laboratory data, no difference was detected in inflammatory reaction between both groups, but in immunological data, especially complement C3 and tuberculin skin test were markedly reduced in HAP. The prognosis were significantly poor in HAP because the fatal rate was higher in HAP than nursing home acquired pneumonia. With regard to HAP in the elderly, severe underlying disease, poor whole body state, aspiration, bacterial resistance to drugs, superinfection and polymicrobial infection were the factors predisposing difficulty in treatment of pneumonia in the elderly. From the above results, prevention is the most necessary in HAP.