RESUMO
BACKGROUND: Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection is a global public health issue, and ceftazidime/avibactam is recommended by international guidelines as the preferred treatment for KPC- and OXA-48-producing CRKP. Since its introduction in Taiwan in 2019, ceftazidime/avibactam-resistant strains have emerged. Our aim is to investigate the mechanisms of ceftazidime/avibactam resistance in CRKP in Taiwan and study their associated fitness costs. METHODS: Ceftazidime/avibactam-resistant CRKP strains with exposure to ceftazidime/avibactam isolated from clinical specimens were consecutively collected at Taipei Veterans General Hospital in 2020. The serial strains exhibiting ceftazidime/avibactam-susceptible and ceftazidime/avibactam-resistant phenotypes isolated from the same patient were characterized using whole-genome sequencing (WGS) and tested for their growth rates and competitive abilities. RESULTS: A total of 35 ceftazidime/avibactam-resistant CRKP strains were identified, with 20 being metallo-ß-lactamase producers. Ten strains harbored KPC variants, exhibiting MIC for ceftazidime/avibactam ranging from 64 to ≥256 mg/L. The 10 strains demonstrating high-level ceftazidime/avibactam resistance possessed mutated KPC variants: KPC-33 (n=3), KPC-31 (n=1), KPC-39 (n=1), KPC-44 (n=1), KPC-58 (n=1), KPC-90 (n=1), and two novel KPC variants. Ceftazidime/avibactam-resistant strains with KPC-33 and KPC-39 showed a significant fitness cost and lower growth rate compared to their parental strains. In contrast, ceftazidime/avibactam-resistant strains with KPC-58 and KPC-58 plus D179Y showed similar growth rates and competitive abilities compared to their parental strains. CONCLUSION: Mutated KPC variants conferred high-level ceftazidime/avibactam resistance in Taiwan. Significant fitness costs were observed in both the ceftazidime/avibactam-resistant KPC-33 and KPC-39 strains. Despite conferring a similar level of ceftazidime/avibactam resistance, different KPC variants could entail varying degrees of fitness costs.
RESUMO
BACKGROUND: The use of remdesivir in patients with coronavirus disease 2019 (COVID-19) and severe renal impairment has been approved; however, limited clinical data exist. Accordingly, we aimed to compare outcomes and adverse events associated with remdesivir in hospitalized patients with COVID-19, with and without severe renal impairment. METHODS: Hospitalized patients with COVID-19 undergoing a 5-day remdesivir course at Taipei Veterans General Hospital from April 1 to July 31, 2022, were enrolled. Comparative analysis of outcomes and safety between patients with or without severe renal impairment (estimated glomerular filtration rate of < 30 mL/min per 1.73 m2) were conducted. Prognostic factors associated with 28-day mortality in patients with severe renal impairment were investigated using logistic regression analysis. RESULTS: A total of 671 hospitalized patients, including 132 patients with severe renal impairment, who received a 5-day course of remdesivir were analyzed. The 28-day mortality was higher in patients with severe renal impairment than in patients without severe renal impairment (15.2% vs. 7.8%). The proportion of patients with acute kidney injury (AKI) and deteriorated liver function after completing remdesivir therapy was similar between the patients with and without severe renal impairment, and the recovery rate of AKI was similar in both groups. The sequential organ failure assessment score was an independent factor associated with 28-day mortality in patients with severe renal impairment. CONCLUSIONS: Remdesivir was well-tolerated in hospitalized patients with COVID-19, regardless of renal function. Our findings support the recent recommendation to administer remdesivir in patients with severe renal impairment.
