Chlortetracycline and oxytetracycline in experimental E. coli pyelonephritis

On experimental haematogenous E. coli pyelonephritis in rabbits produced by temporary ligature of the ureter the effect of chlortetracycline (CTC) and oxytetracycline (OTC) was compared. When the treatment was initiated “early” (i.e. on the day when the microorganisms were injected), the development of the inflammatory process could be prevented in 85%; no marked differences were found between the effect of CTC and OTC. When “delayed” treatment was applied (i.e. two days after injection of the microorganisms) no marked inflammatory changes developed in the kidneys of 22% of the CTC-treated rabbits and in 32% of the OTC-treated rabbits; after OTC therapy the renal tissue was always sterile, after CTC therapy positive bacteriological findings persisted in 37,5%.