Carbapenem-resistant infections after liver transplantation: Drug resistance, risk factors and impact on prognosis.

Background: Liver transplant (LT) recipients are susceptible to carbapenem-resistant (CRKP) infections. Comprehensive research addressing the incidence, timing, infection sites, resistance patterns, treatment options, and associated risk factors among LT recipients with CRKP is now lacking.

Aim: To assess the incidence, resistance, therapy, and risk factors of CRKP infections post-LT, and to evaluate the impact of them on prognosis.

Methods: A retrospective study was conducted, including 430 consecutive patients who underwent LT between January 2015 and June 2023. This study aimed to investigate the risk factors for CRKP infections and their influence on outcomes using logistic regression analysis.

Results: Among the 430 patients who underwent LT, 20 (4.7%) experienced at least one documented CRKP infection within 3 months post-transplantation. The median time from LT to the onset of CRKP infections was 6.5 days. The lungs and bloodstream were the most common sites of CRKP infections. CRKP isolates were relatively susceptible to ceftazidime/avibactam (93.7%), polymyxin B (90.6%), and tigecycline (75.0%) treatment. However, all isolates were resistant to piperacillin/tazobactam, ceftazidime, cefepime, aztreonam, meropenem, and levofloxacin treatment. Recipients with CRKP infections had a mortality rate of 35%, the rate was 12.5% for those receiving ceftazidime/avibactam therapy. Multivariate analysis identified female sex [odds ratio (OR) = 3.306; 95% confidence interval (CI): 1.239-8.822; = 0.017], intraoperative bleeding ≥ 3000 mL (OR = 3.269; 95%CI: 1.018-10.490; = 0.047), alanine aminotransferase on day 1 post-LT ≥ 1500 U/L (OR = 4.370; 95%CI: 1.686-11.326; = 0.002), and post-LT mechanical ventilation (OR = 2.772; 95%CI: 1.077-7.135; = 0.035) as significant variables associated with CRKP. CRKP infections were related to an intensive care unit length (ICU) of stay ≥ 7 days and 6-month all-cause mortality post-LT.

Conclusion: CRKP infections were frequent complications following LT, with poor associated outcomes. Risk factors for post-LT CRKP infections included female sex, significant intraoperative bleeding, elevated alanine aminotransferase levels, and the need for mechanical ventilation. CRKP infections negatively impacted survival and led to prolonged ICU stays.