A new method for producing a chronic E. coli pyelonephritis in rabbits.

Chronic pyelonephritis, especially that caused by the most common invader E. coli, corresponding satisfactorily to the pathophysiology of the human disease is difficult to reproduce. We have developed a pattern of infection with which we succeeded reliably in producing a chronic E. coli pyelonephritis. This was achieved by inserting a plastic catheter into the renal pelvis. A suspension of E. coli was injected via the catheter into the renal pelvis of 32 rabbits. This pattern of infection takes a chronic progressive course and, in all cases, results in typical macroscopic and histological changes in the kidney. The bacterial excretion in the urine remains unchanged over a period of months. With the experimental procedure described, the pathogenesis and pathophysiology of chronic E. coli pyelonephritis can be clearly studied. Drugs currently used on patients can be tested for their effectiveness in long-term application.