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Experimental pyelonephritis in the monkey. III. Pathophysiology of ureteral malfunction induced by bacteria
Abstract:
Coliforms given intravenously usually fail to produce pyelonephritis unless urinary obstruction or other anatomic abnormalities are present. Previously, we had observed progressive pyelonephritis after hematogenous infection only in monkeys which seemed to have an abnormality of ureteral function. To further test this observation, unilateral ureteral instillation of Escherichia coli 04.06, and 0111 was carried out under base line pressure conditions. Animals infected with E. coli 04 showed unilateral absence of ureteral peristalsis, delay in excretion of radionuclide on scintiphoto studies, and ureteritis histologically. This study confirms that certain strains of E. coli cause ureteral dysfunction. So called nonobstruction pyelonephritis may really be obstructive.
Insights
Certain Escherichia coli strains can cause ureteral dysfunction, leading to pyelonephritis even without apparent obstruction. This suggests that some nonobstructive pyelonephritis cases may actually involve obstructive mechanisms due to bacterial infection.
Area of Science:
- Urology
- Microbiology
- Nephrology
Background:
- Pyelonephritis typically requires urinary obstruction or anatomical abnormalities for coliform bacteria to establish infection.
- Previous observations suggested ureteral dysfunction in monkeys with hematogenous infection led to progressive pyelonephritis.
Purpose of the Study:
- To investigate the role of specific Escherichia coli strains in causing ureteral dysfunction.
- To determine if ureteral dysfunction induced by E. coli can lead to pyelonephritis in the absence of overt obstruction.
Main Methods:
- Unilateral ureteral instillation of specific Escherichia coli strains (04, 06, 0111) in a preclinical model.
- Assessment of ureteral peristalsis, radionuclide excretion via scintiphoto studies, and histological examination of ureteritis.
Main Results:
- Infection with E. coli 04 resulted in unilateral absence of ureteral peristalsis.
- Delayed radionuclide excretion was observed on scintiphoto studies in infected animals.
- Histological analysis confirmed ureteritis in animals infected with E. coli 04.
Conclusions:
- Certain strains of E. coli, specifically E. coli 04, are capable of inducing ureteral dysfunction.
- The findings suggest that pyelonephritis previously categorized as nonobstructive may, in fact, be obstructive due to infection-induced ureteral dysfunction.