Clinical analysis of community-acquired pneumonia in the elderly.

Objective To evaluate the clinical features, etiology, and outcome of patients over 65 years old hospitalized for community-acquired pneumonia. Patients Eighty-four patients (50 males, 34 females) hospitalized for community-acquired pneumonia in Kawasaki Medical School Kawasaki Hospital between April 1998 and March 2000. Results Most of the patients had respiratory symptoms or signs, but over one-third also had atypical symptoms of pneumonia such as dyspnea, consciousness disturbance, and gastrointestinal symptoms. The causative microorganisms were identified in 48% of these patients. Streptococcus pneumoniae (13%), respiratory viruses (13%), Haemophilus influenzae (8%) and Mycobacterium tuberculosis (8%) were frequently identified, but Mycoplasma pneumoniae was less frequently noted in the elderly. Double infection was recognized in 19% and a combination of some virus and bacteria in 13%. Treatment consisted of the administration of second or third generation cephalosporin antibiotics intravenously, because antibiotics had already been preadministered in 39%. The prognosis was poor (mortality rate 9%) for the elderly with community-acquired pneumonia despite mechanical ventilation in 8%. Conclusions Although the range of microorganisms causing community-acquired pneumonia differed slightly from that in previous reports; namely, lower frequency of Chlamydia pneumoniae and Legionella pneumophila, it is suggested that the initial antibiotic treatment should always cover S. pneumoniae and H. influenzae. In addition, since a prevalence of virus infections related to the increase in community-acquired pneumonia in the elderly was found in this study, the routine use of influenza vaccine and pneumococcal vaccines in the elderly is recommended to reduce the high mortality rate.(Internal Medicine 40: 703-707, 2001)