Investigation of Therapeutic Efficacy of Intravesical Tigecycline Administration in Rats with Cystitis Induced by Extensively Drug-Resistant (XDR), Tigecycline-Sensitive Acinetobacter baumannii Strain

Background: This study aimed to evaluate the therapeutic efficacy of intravesical tigecycline administration in a rat model of cystitis induced by a tigecycline-sensitive, extensively drug-resistant (XDR) Acinetobacter baumannii strain. Methods: Thirty-six female Wistar albino rats were inoculated intravesically with XDR A. baumannii to induce cystitis. Twenty-four rats that developed infection were divided into four groups: untreated control, saline irrigation, low-dose tigecycline (6.25 mg/kg), and high-dose tigecycline (25 mg/kg). Microbiological clearance was assessed via urine cultures on days 3 and 5. Bladder tissues were analyzed histopathologically and for genotoxicity using the Comet assay. Results: On day 5, microbiological clearance was significantly higher in tigecycline-treated groups compared to controls (p = 0.028). Histopathology revealed significantly more inflammation in the high-dose tigecycline group (p = 0.029). Genotoxicity was observed in both tigecycline groups, independent of dose (p < 0.05). Conclusions: Intravesical tigecycline demonstrated microbiological efficacy against XDR A. baumannii-induced cystitis. However, its inflammatory and genotoxic potential necessitates further preclinical evaluation.