Risk factors for mortality and impact of broad-spectrum cephalosporin resistance on outcome in bacteraemic intra-abdominal infections caused by Gram-negative bacilli

Abstract

Background: Although several studies have evaluated the association of antimicrobial resistance and mortality in patients with Gram-negative bacteraemia, little is known regarding the impact of antimicrobial resistance on outcome in patients with intra-abdominal infections caused by Gram-negative bacilli (GNB). This study was performed to evaluate the impact of broad-spectrum cephalosporin resistance on outcome in patients with intra-abdominal infections caused by GNB. Methods: Data on 365 patients with bacteraemic intra-abdominal infections caused by GNB were obtained from the database of a nationwide surveillance for bacteraemia, and analyzed. Results: Seventy-one of the 365 patients (19.5%) harboured broad-spectrum cephalosporin-resistant infections. When compared with patients with susceptible infections, the group of patients with resistant infections had a lower treatment success rate at 7 days after the initiation of antimicrobial therapy (73.2% vs 85.0%, p = 0.023). However, the 30-day mortality rate for the resistant group was not significantly higher than for the susceptible group (16.9% vs 10.2%, p = 0.112). Multivariable analysis showed that severe sepsis was the most important risk factor associated with mortality (odds ratio 4.91, 95% confidence interval 2.26–10.63), along with underlying liver disease, nosocomial acquisition, underlying solid tumour, and higher Pitt bacteraemia score (all p < 0.05). Antimicrobial resistance and inappropriate initial antimicrobial therapy were not found to be associated with mortality. Conclusions: Our data suggest that antimicrobial resistance and inappropriate initial antimicrobial therapy may not be significant determinants for the prognosis in intra-abdominal infections caused by GNB, for which drainage or decompression procedures of intra-abdominal sources are often necessary.

Keywords::

• Gram-negative bacterial infections
• abdominal cavity
• bacteraemia
• treatment outcome
• cephalosporin resistance

Acknowledgements

This study was supported by a grant from the Korean Health 21 R & D Project, Ministry of Health, Welfare, & Family Affairs, Republic of Korea (A084063).

KONSID members are as follows; Jae-Hoon Song, Cheol-In Kang, Doo Ryeon Chung, Kyong Ran Peck, Nam Yong Lee, Yae Jean Kim (Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul), Kwan Soo Ko (Sungkyunkwan University School of Medicine, Suwon), Joon-Sup Yeom (Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul), Hyun Kyun Ki, Hae Suk Cheong (Konkuk University Hospital, Seoul), Jun Seong Son (Kyunghee University Hospital, Seoul), Choon Kwan Kim (Seoul Veterans Hospital, Seoul), Jin Seo Lee (Kangdong Sacred Heart Hospital, Seoul), Seung Soon Lee (Hallym University Sacred Heart Hospital, Seoul), Eun Seok Kim (Anyang Sam Hospital, Anyang), Yeon-Sook Kim (Chungnam National University Hospital, Daejon), Ji-Young Rhee (Dankook University Hospital, Cheonan), Sook-In Jung, Kyung Hwa Park (Chonnam National University Hospital, Gwangju), Shin-Woo Kim, Hyun-Ha Chang (Kyungpook National University Hospital, Daegu), Seong Yeol Ryu (Keimyung University Dongsan Medical Center, Daegu), Ki Tae Kwon (Daegu Fatima Hospital, Daegu), Hyuck Lee, Dong Sik Jung (Dong-A University Hospital, Busan), Chisook Moon (Inje University Busan Paik Hospital, Busan), Sang Taek Heo (Gyeongsang National University Hospital, Jinju), and Sang Yop Shin (Cheju National University Hospital, Jeju).

Declaration of interest: No conflicts for all authors.