Abstract
Non-typhoidal Salmonella (NTS) represents a growing public health concern worldwide due to its increasing antimicrobial resistance and substantial disease burden, yet data from Romania remain limited. We conducted the first regional 7-year retrospective study of NTS-associated diarrhea among hospitalized patients, focusing on resistance trends and clinical factors associated with disease severity. This study included all laboratory-confirmed Salmonella infections admitted for acute diarrheal disease to the "Sfânta Parascheva" Clinical Hospital of Infectious Diseases, Iași (January 2018-December 2024). Patient data were extracted from electronic medical records and analyzed using SPSS (v31.0), with statistical significance set at p < 0.05. Among the isolates obtained from the 698 included patients, most belonged to serogroup D (63.6%), followed by B (21.8%) and C (14.0%). Overall resistance rates were 12.3% for ampicillin, 3.6% for trimethoprim-sulfamethoxazole and 29.9% for ciprofloxacin, with a significant yearly increase observed only for ciprofloxacin (OR = 1.21, p < 0.001). Cardiovascular comorbidities were independently associated with prolonged hospitalization (>5 days) (OR = 2.25, p = 0.007). Invasive infections occurred in 14 patients (2%). Given the high ciprofloxacin resistance and the additional impact of comorbidities on disease severity, there is a need for ongoing surveillance and targeted management strategies.