Multiple drug resistance (MDR) intra-abdominal infections (IAIs) are associated with noteworthy direct and societal costs. Compared to previous studies, the present one takes both resistance rate and total medical costs (TMCs) into consideration, focusing on the impact of MDR on TMCs in IAIs, as well as further estimating the additional costs at a national level.

All inpatients discharged between 1 January 2014, and 31 December 2015 from a teaching hospital were included. Due to limits in budget and the large number of inpatients, the randombetween (bottom, top) function was applied to randomly select 40 percent of patients per year. Subsequently, we manually screened out 254 patients with IAIs, according to the International Classification of Disease (tenth revision) and electronic medical records. Eventually, 101 IAIs patients were included, in which 37 were infected by non-MDR bacteria and 64 by MDR bacteria. The Kruskal-wallis non-parametric test and multiple linear regression were employed to analyze the effect of single and multiple variables on TMCs.

Compared to patients with non-MDR infections, those with MDR were associated with significantly higher TMCs, higher antimicrobial costs, increased insurance, combination antimicrobial therapy, higher usage of antimicrobial agents, greater number of pathogens, longer length of stay, and longer intensive care unit stays. In addition, the average TMCs among patients with MDR were CNY131,801.17 (1USD was equal to CNY 6.227 in 2015), which were CNY 90,200.99 higher than those with non-MDR infections. If our results are generalizable to the whole country, the total attributable TMCs are estimated to be CNY37.06 billion, and the societal costs of CNY111.18 billion in 2015.

This real-world data analysis demonstrated the significant excessive burden MDR infections are posing to the current Chinese healthcare system in terms of both TMCs and healthcare resource utilization. Enhanced antimicrobial stewardship in China is necessary to curb the distribution of MDR bacteria.