[Histopathological observations of experimental hematogenous infection with Pseudomonas aeruginosa in mice (author's
Abstract:
The effect of intravenous injection of Pseudomonas aeruginosa in mice was studied in various conditions : dose of bacteria injected (2.5 X 10(6) to 4.5 X 10(7)) , moment of necropsy (one hour to 4 months after infection), number of injections (one, two and eight). Gross and microscopic examinations of tissues included kidney, lung, spleen and liver. The frequency, the type and the time of appearance of the lesions depend upon the dose of organisms, upon the individual susceptibility of the mouse and upon the number of injections. Abscesses preferentially localised in kidneys appeared in mice that received only one injection of bacteria. They were visible to the naked eye as soon as two days after inoculation with a large dose. Granulomatous inflammatory reaction was observed in the different tissues, however it was predominantly seen in the kidney and in animals that received several injections. In the liver and the spleen hyperplasia and hypertrophy of lymphoid, myeloid, megacaryocytic and mononuclear phagocytic cells were observed. This model of experimental pyelonephritis due to P. aeruginosa seems to us useful to study the factors promoting localisation and multiplication of this organism in a tissue.
Insights
Pseudomonas aeruginosa infection in mice causes kidney abscesses and inflammatory reactions. Lesion severity depends on bacterial dose, mouse susceptibility, and injection frequency, informing pyelonephritis research.
Area of Science:
- Microbiology
- Immunology
- Pathology
Context:
- Investigating the pathogenesis of Pseudomonas aeruginosa infections.
- Utilizing a murine model to study bacterial dissemination and host response.
Purpose:
- To determine the impact of bacterial dose, injection frequency, and host susceptibility on lesion development.
- To characterize the gross and microscopic pathology of Pseudomonas aeruginosa-induced pyelonephritis.
Summary:
- Intravenous inoculation of Pseudomonas aeruginosa in mice, with varying doses and injection schedules, resulted in dose- and frequency-dependent lesions.
- Kidneys were primary sites for abscess formation, particularly after single high-dose injections.
- Granulomatous inflammation and hyperplasia/hypertrophy in lymphoid and myeloid cells were observed in affected tissues.
Impact:
- Establishes a valuable experimental model for studying Pseudomonas aeruginosa pyelonephritis.
- Provides insights into factors influencing bacterial localization and multiplication within host tissues.
- Facilitates research on host-pathogen interactions and therapeutic strategies for P. aeruginosa infections.
