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Treatment of staphylococcal pyelonephritis in rats with N-formimidoyl thienamycin
Abstract:
The therapeutic efficacy of N-formimidoyl thienamycin alone or coadministered with MK0791, an inhibitor of renal dehydropeptidase-I, compared to methicillin in experimental pyelonephritis in rats was investigated. Pyelonephritis was produced with a methicillin-sensitive strain (2776) and a methicillin-resistant strain (Berman) of Staphylococcus aureus. N-formimidoyl thienamycin alone or coadministered with the inhibitor was significantly better than methicillin when treating methicillin-sensitive or methicillin-resistant infection. There was a trend suggesting that N-formimidoyl thienamycin coadministered with MK0791 was overall the best agent. These studies show that N-formimidoyl thienamycin is efficacious in the treatment of S. aureus pyelonephritis in the rat regardless of methicillin sensitivity, and this agent plus the dehydropeptidase inhibitor should be considered in the treatment of such infections.
Insights
N-formimidoyl thienamycin effectively treats Staphylococcus aureus pyelonephritis in rats, outperforming methicillin. Combining it with MK0791, a dehydropeptidase-I inhibitor, showed the best therapeutic results.
Area of Science:
- Pharmacology
- Infectious Diseases
- Nephrology
Background:
- Pyelonephritis is a serious kidney infection often caused by Staphylococcus aureus.
- Methicillin resistance in Staphylococcus aureus poses a significant therapeutic challenge.
- N-formimidoyl thienamycin is a carbapenem antibiotic with broad-spectrum activity.
Purpose of the Study:
- To evaluate the therapeutic efficacy of N-formimidoyl thienamycin, alone or with MK0791, against experimental Staphylococcus aureus pyelonephritis in rats.
- To compare the efficacy of N-formimidoyl thienamycin-based regimens with methicillin.
- To assess the impact of methicillin sensitivity of Staphylococcus aureus strains on treatment outcomes.
Main Methods:
- Experimental pyelonephritis was induced in rats using both methicillin-sensitive and methicillin-resistant strains of Staphylococcus aureus.
- Animals were treated with N-formimidoyl thienamycin alone, N-formimidoyl thienamycin coadministered with MK0791 (a renal dehydropeptidase-I inhibitor), or methicillin.
- Therapeutic efficacy was assessed by comparing treatment outcomes between the different groups.
Main Results:
- N-formimidoyl thienamycin, both alone and in combination with MK0791, demonstrated significantly superior efficacy compared to methicillin in treating pyelonephritis caused by both methicillin-sensitive and methicillin-resistant Staphylococcus aureus.
- A trend indicated that the combination of N-formimidoyl thienamycin and MK0791 yielded the best overall therapeutic results.
- The efficacy of N-formimidoyl thienamycin was consistent regardless of the methicillin sensitivity of the infecting Staphylococcus aureus strain.
Conclusions:
- N-formimidoyl thienamycin is a highly effective therapeutic agent for Staphylococcus aureus pyelonephritis in a rat model, irrespective of methicillin resistance.
- The combination of N-formimidoyl thienamycin with the dehydropeptidase-I inhibitor MK0791 warrants consideration for treating such infections.
- These findings support the potential clinical utility of N-formimidoyl thienamycin in managing complicated Staphylococcus aureus kidney infections.
