Shift in the Dominant Sequence Type of Carbapenem-Resistant Klebsiella pneumoniae Bloodstream Infection from ST11 to ST15 at a Medical Center in Northeast China, 2015–2020

Abstract

Objective: To investigate the clinical characteristics and molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae (CRKP) bloodstream infection at a medical center in northeast China, especially after coronavirus disease (COVID-19) pandemic. Methods: Fifty-one patients were diagnosed with CRKP bloodstream infection between January 2015 and December 2020, among which 42 isolates were available for further study. Species identification and antibiotic susceptibilities were tested with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and VITEK 2 systems. Carbapenemase genes, virulence genes and MLST genes were detected by polymerase chain reaction. Moreover, the string test and serum killing assay were performed to evaluate the virulence of the CRKP isolates. Results: During the six-year period, the detection rate of CRKP in bloodstream infection showed an increasing trend, with the intensive care unit, hematology and respiratory medicine wards mainly affected. Molecular epidemiology analyses showed that KPC-2 was the dominant carbapenemase gene. In addition, the dominant sequence type (ST) of CRKP shifted from ST11 to ST15 strains, which were all sensitive to amikacin in contrast to the ST11 stains. Furthermore, ST15 CRKP strains were positive for the KfuB virulence gene and more resistant to serum killing compared to the ST11 CRKP strains. Nonetheless, the mortality rate of patients infected with ST11 and ST15 CRKP did not show any significant differences. Conclusion:A shift in the dominant sequence type of CRKP bloodstream infections from ST11 to ST15 was observed during the years 2015-2020. Compared to ST11, the ST15 CRKP strains showed amikacin sensitivity, positivity for KfuB gene, and serum resistance, which may indicate stronger virulence.

The Threat of Carbapenem-Resistant Gram-Negative Bacteria in Patients with Hematological Malignancies: Unignorable Respiratory Non-Fermentative Bacteria-Derived Bloodstream Infections

“…Recently, several studies have consistently proved an increasing trend of CR rates among these two major groups of bacteria in HMs patients with BSI. 4 , 6 , 11 Similarly, in line with the results of a European study, 4 our findings revealed that CR was undetectable among Enterobacteriaceae in 2010–2012, but upgraded to 14.8% in E. coli and 32% in K. pneumoniae during 2019–2020. Additionally, CR is more commonly observed in non-fermenting bacteria compare to Enterobacteriaceae, especially in A. baumannii and P. aeruginosa .…”

“…Patients with HMs are more susceptible to developing CRGNB-related BSI than patients with other malignancies. 6 In our study, prior exposure history to carbapenem and the presence of urinary catheters were independent risk factors for CRGNB-caused BSI in patients with HM. In addition, studies from others also suggest that patients with colonization or infection history of CRGNB were also at high risk of CRGNB BSI.…”

“…CRGNB BSI poses a significant threat to the prognosis of HM patients, overall mortality rates of CRGNB BSI in HM patients ranging from 45% to 80% were reported across different studies. 3 , 6 , 8 , 9 Nizar Andria et al reported that the 14-day mortality rate was higher in patients with CRGNB BSI compared to CSGNB [45.6% (47/103) versus 15% (48/320), respectively (P < 0.001)]. 3 In our study, a significantly higher 7-day mortality was also observed in patients with CRGNB BSI compared to patients with CSGNB BSI (31.9% vs 9.7%, P < 0.001), but it was still lower than other studies.…”

Multicenter Genomic Analysis of Carbapenem-Resistant Klebsiella pneumoniae from Bacteremia in China

“…KPC producing ST15 K. pneumoniae have been found causing outbreaks ( 37 ), and is the second most frequent CRKP clone in hospital infections after ST11 ( 38 , 39 ). However in a recent surveillance study conducted in one hospital in northeast China, Chen et al ( 40 ), reported a shift in dominance from ST11 to ST15 during the year 2020 compared to the trend observed between 2015 to 2019. Susceptibility to amikacin was a prominent characteristic of ST15 isolates, while resistance to this antibiotic was reported in ST11 isolates in both the previous and our study.…”

The Collateral Effects of COVID-19 Pandemic on the Status of Carbapenemase-Producing Pathogens

“…This supports concerns regarding emergence of carbapenemases in the wake of the global pandemic ( Gomez-Simmonds et al., 2021 ). In other settings, a depicted change occurred in K. pneumoniae ST and its virulence traits over 5 years since 2015, where 2020 witnessed a dominant shift from ST11 to ST15, and this may be ascribed to COVID-19 ( Chen et al., 2021 ). A review of studies on carbapenem-resistant K. pneumoniae in COVID-19 patients from 6 countries found that majority of infected patients (84%) were males with mean age of 61 years, and predominant carbapenemases were KPC and NDM.…”