Background: Intra-abdominal infections (IAIs) caused by Stenotrophomonas maltophilia have rarely been reported. This study aimed to describe the clinical characteristics and risk factors for mortality among patients with S. maltophilia IAIs. Methods: A retrospective study was conducted on inpatients with IAIs caused by S. maltophilia at Tri Service General Hospital from 2004 to 2017. Clinical and microbiologic data of the included cases were reviewed via medical charts and microbiology databases. Multivariable logistic regression analyses were performed to identify risk factors for in-hospital death. Results: In total, 110 patients were diagnosed with S. maltophilia IAIs. Malignancy (56.3%) and liver cirrhosis (35.3%) were the most commonly identified underlying diseases. The major causes of S. maltophilia IAIs were biliary tract infection (42.7%), recent abdominal surgery (35.4%), and spontaneous bacterial peritonitis (20.0%). Polymicrobial infections were observed in 84 (76.4%) patients. In addition to S. maltophilia, co-cultured bacteria (n = 140) included Enterobacterales, representing 19.3% (27/140) of the total isolates, and non-fermentative aerobes, comprising 29.3% (41/140). In addition, anaerobic bacteria and fungi accounted for 9.2% (13/140) and 10% (14/140), respectively. The overall mortality rate was 40.9%. Multivariable logistic regression analysis revealed that high Sequential Organ Failure Assessment scores and malignancies were independent risk factors for mortality, while the immediate administration of appropriate antibiotics targeting S. maltophilia was a protective factor (p < 0.05). Conclusions: Patients with an underlying malignancy or liver cirrhosis were at risk for IAIs caused by S. maltophilia. The prompt initiation of effective antibiotics against S. maltophilia is critical for achieving favorable outcomes.
Keywords: Stenotrophomonas maltophilia; intra-abdominal infection; mortality; risk.