一次医療における呼吸器感染症の研究 (III) 個人開業医21機関における呼吸器由来病原細菌の分離状況と臨床的意義

Abstract

The bacteriology of the isolates from the throat swab and the sputum respectively of 2,539 patients with respiratory infections visiting 21 private clinics in Tohoku district of Japan during the period from January to April in 1989 was documented. Of the 2,539 patients, 1,694 had an acute upper respiratory infection, 609 had acute bronchitis, 46 had acute pneumonia, 84 had acute exacerbation of chronic respiratory infections and 106 had respiratory infections without diagnosis registered. 1887 (74.3%) strains of potential pathogens were recovered from 1507 (59.4%) of the 2539 cases. The rate of recovery of potential pathogens was very high in patients of the younger age. These patients had elevated body-temperature. There were statistically significant differences in recovery rate when classified by diagnosis, prefecture and the period of investigation. Of the 1,887 strains, 996 (52.8%) were gram-positive and 891 (47.2%) were gram-negative bacteria. The rate of recovery of gram-negative bacteria was high in patients who were less than 10 years old and more than 51 years old, in patients with pneumonia and chronic respiratory infections, and in patients with fever. Of the 1,887 strains, those which exceeded 100 were Staphylococcus aureus (481 strains), Haemophilus influenzae (340 strains), Streptococcus pneumoniae (329 strains), Streptococcus pyogenes (117 strains) and Acinetobacter spp. (100 strains). Species other than those mentioned above had less than 100 strains. In this group there were 39 strains of Branhamella catarrhalis, 32 strains of Escherichia coli, 97 strains of Klebsiella spp., 40 strains of Enterobacter spp., 25 strains of Serratia spp., 12 strains of Pseudomonas aeruginosa and 43 strains of Pseudomonas putida. There was a remarkable difference in recovery rate of each species when classified by diagnosis, age class, prefecture and the period of investigation, respectively. The above results indicated that gram-positive bacteria are more frequent than gram-negative bacteria, that enterobacteriaceae and glucose-non-fermentative gram-negative bacteria are only rarely found in primary care clinics, and that the bacteriology in primary care clinic is different from that of medical school-affiliated hospitals.