Yearly changes of isolated organisms from the respiratory tract in Hokusho Central Hospital

: Isolated organisms from the respiratory tract have been studied in our hospital from 1986 to 1993. The total number of samples were 18,345 and samples which showed 10(5) cfu/ml organisms were 8648 in our hospital for 8 years. Enterobacteriacae, Pseudomonas aeruginosa, Haemophilus influenzae, Streptococcus pneumoniae, and glucose nonfermenting gram-negative rods were major isolates in 8 years. Haemophilus influenzae, which used to be the commonest isolate, decreased from 10.9% in 1993 while Enterobacteriacae increased from 8.9% in 1986 to 17.6% in 1993. S. pneumoniae and H. influenzae were major isolates from out-patients consisting of 50%, followed by Enterobacteriacae, P. aeruginosa and MSSA. Enterobacteriacae and P. aeruginosa were major isolates from in-patients, followed by MRSA and beta-Streptococcus. Streptococcus agalactiae, Serratia marcescens and Corynebacterium spp. prevailed especially in the geriatric ward. S. pneumoniae, H. influenzae and M. catarrhalis were major isolates from patients with pneumoconiosis, especially in winter.