[Typing of E. coli rough strains with phages (author's transl)]

Two phage-sets were used for the typing of 408 E. coli rough strains isolated from patients with urinary tract infections, Using the 13 phages A to M (11), we were able to type 225 (55.1 per cent) strains. 143 (35 per cent) of these strains were found to have K antigen, 84 different phage patterns could be recognized. Phage patterns GHK, M, F, and AM were the most common ones found. The application of the typical rough phages Br10, C21, 6SR, FP1, T4, and the Felix O (FO) phage led to the successful typing of 143 (35 per cent) strains, 80 of which (19.6 per cent) had a K antigen. About 70 per cent of the strains typable were found to belong to phage patterns which were represented by single phages, 24 different R phage patterns were observed. Considering both phage-sets the total typability amounted to 67 per cent. It is concluded that phage typing may be useful for the typing of E. coli rough strains in urinary tract infections in order to distinguish between relapse and reinfection.