1986 Volume 60 Issue 9 Pages 1010-1021
The purpose of this study is to make rapid diagnosis of pathogens in sputum and autopsied lung in pneumonia cases as nosocomial infection or terminal infection. Rabbits were immunized with heat stable antigens purified from culture filtrates of each 10 strains of E. coli, K. pneumoniae and P. aeruginosa, which are most frequently isolated from sputum in nosocomial pneumonia. These antisera were absorbed with various other bacterial antigens in order to elevate specificity. The specificity and sensitivity were evaluated by the method of indirect fluorescent assay.
Among 120 clinical isolates (each 40 strains in 3 species), 40 strains of E. coli were examined by this method. Twenty isolates were positive to E. coli antisera. Consequently, the correct diagnosis rate was confirmed to be 50%. Three out of 40 strains were positive to Klebsiella antisira and no isolate showed positive to Pseudomonas antisira, those results showed that miss diagnosis rate was 7.5%.
As six strains were positive to all three kinds of antisera and 11 strains were negative to these three kinds of antisera, those resuts showed that undiagnosis rate was 42.5%. The correct diagnosis rates were 47.5% and 67.5%, miss diagnosis rates were 0% and 0%, and the undiagnosis rates were 52.5% and 32.5% to anti-Klebsiella antisera and anti-Pseudomonas antisera, respectively.
Among three antisera, anti-Pseudomonas antisera was the best for diagnosis with regard to specificity. The specificity and sensitivity of these antisera are not satisfactory for clinical diagnosis, but these are valuable in supportive reagents for rapid indentification until bacterial data is confirmed.
