Introduction: Antibiotic resistant Salmonella typhimurium and S. typhi are a critical health risk in both human and animal medicine. Increasing multidrug resistant strains of Salmonella spp. and limited effect of antibiotic led to combined nanomaterial with antibiotic to combat multidrug resistant of pathogenic bacteria.
Aim of the Work: The aim of this study was to evaluate the antibacterial effects of a combined therapy of AgNPs and Amoxicillin against S. typhimurium and S. typhi, and study impact them of histopathological change in liver and spleen of mice.
Material and Method: S. typhi were isolated from patients suffering typhoid fever (systemic infection), and S. typhimurium were isolated from patients suffering gastroenteritis including diarrhea. Biosynthesis of AgNPs through reduction of silver nitrate with supernatant of klebsiella pneumonia and reducing agent (glucose). The Amoxicillin and AgNps were prepared according to CLCSI to calculated MIC in the chequerbord method and determined FIC Index. The mice were gavaged with 0.2 ml of Salmonella spp. Suspension according to LD50 dose and the control group was gavaged with0.2 ml sterile normal saline. Once a day total daily dose of 100 mg/kg of body weight. After 7 days treatment, assessment of AgNP combined with Amoxicillin in liver and spleen of mice by histopathological study.
Result: All Salmonella spp isolates are diagnostic by viteck2 compact system techniques. The LD50 are 3×108 and1 x107 cfu/ml for S. typhi and S. typhimurium , receptively. The FIC index values for AgNps, amoxicillin combination were 0.5 and 0.7 for S. typhimurium and S. typhi, receptively. The present study of results histopathological of liver treatment AgNps mixed with Amoxicillin in mice infected with S. typhi were binucleated hepatocyte with congested blood vessel and megakaryocyte hyperplasia in spleen. Histopathological spleen treatment of mice by AgNps mixed with Amoxicillin that infected with S. typhimurium were showed white pulp atrophy, while Histopathological changes in the liver are hydropic degeneration with mild kupffer cell proliferation.
Conclusion: The study showed High doses exposure of AgNps combined with Amoxicillin on mice for testing may cause a mild to moderate toxicity.