Citations

Abstract Background Carbapenem-resistant Acinetobacter baumannii (CRAb) is 1 of the most problematic antimicrobial-resistant bacteria. We sought to elucidate the international epidemiology and clinical impact of CRAb. Methods In a prospective observational cohort study, 842 hospitalized patients with a clinical CRAb culture were enrolled at 46 hospitals in five global regions between 2017 and 2019. The primary outcome was all-cause mortality at 30 days from the index culture. The strains underwent whole-genome analysis. Results Of 842 cases, 536 (64%) represented infection. By 30 days, 128 (24%) of the infected patients died, ranging from 1 (6%) of 18 in Australia-Singapore to 54 (25%) of 216 in the United States and 24 (49%) of 49 in South-Central America, whereas 42 (14%) of non-infected patients died. Bacteremia was associated with a higher risk of death compared with other types of infection (40 [42%] of 96 vs 88 [20%] of 440). In a multivariable logistic regression analysis, bloodstream infection and higher age-adjusted Charlson comorbidity index were independently associated with 30-day mortality. Clonal group 2 (CG2) strains predominated except in South-Central America, ranging from 216 (59%) of 369 in the United States to 282 (97%) of 291 in China. Acquired carbapenemase genes were carried by 769 (91%) of the 842 isolates. CG2 strains were significantly associated with higher levels of meropenem resistance, yet non-CG2 cases were over-represented among the deaths compared with CG2 cases. Conclusions CRAb infection types and clinical outcomes differed significantly across regions. Although CG2 strains remained predominant, non-CG2 strains were associated with higher mortality. Clinical Trials Registration. NCT03646227.

Abstract Background Carbapenemase-producing (CP) Escherichia coli (CP-Ec) are a global public health threat. We aimed to describe the clinical and molecular epidemiology and outcomes of patients from several countries with CP-Ec isolates obtained from a prospective cohort. Methods Patients with CP-Ec were enrolled from 26 hospitals in 6 countries. Clinical data were collected, and isolates underwent whole-genome sequencing. Clinical and molecular features and outcomes associated with isolates with or without metallo-β-lactamases (MBLs) were compared. The primary outcome was desirability of outcome ranking (DOOR) at 30 days after the index culture. Results Of the 114 CP-Ec isolates in Consortium on resistance against carbapenems in Klebsiella and other Enterobacterales-2 (CRACKLE-2), 49 harbored an MBL, most commonly blaNDM-5 (38/49, 78%). Strong regional variations were noted with MBL-Ec predominantly found among patients in China (23/49). Clinically, MBL-Ec were more often from urine sources (49% vs 29%), less often met criteria for infection (39% vs 58%, P = .04), and had lower acuity of illness when compared with non–MBL-Ec. Among patients with infection, the probability of a better DOOR outcome for a randomly selected patient with MBL-Ec as compared with non–MBL-Ec was 62% (95% CI: 48.2–74.3%). Among infected patients, non–MBL-Ec had increased 30-day (26% vs 0%; P = .02) and 90-day (39% vs 0%; P = .001) mortality compared with MBL-Ec. Conclusions Emergence of CP-Ec was observed with important geographic variations. Bacterial characteristics, clinical presentations, and outcomes differed between MBL-Ec and non–MBL-Ec. Mortality was higher among non-MBL isolates, which were more frequently isolated from blood, but these findings may be confounded by regional variations.

Introduction: Prior studies (predominantly from Europe) have demonstrated blood culture-negative endocarditis due to Bartonella. Our objective was to describe three cases of Bartonella quintana endocarditis identified within one year at a large hospital in Washington, DC, USA. Case presentation: We constructed a descriptive case series from a retrospective review of medical records from April to December 2013 at an 800-bed urban hospital. All three patients (ages: 52, 55 and 57 years) were undomiciled/homeless men with a history of alcoholism. Although they had negative blood cultures, echocardiography demonstrated aortic/mitral valve perforation and regurgitation in one patient, aortic/mitral valve vegetation with mitral regurgitation in the second patient, and aortic valve vegetation with regurgitation in the third patient. The patients had positive Bartonella quintana serum immunoglobulin G (IgG) with negative immunoglobulin M (IgM). PCR on DNA extracted from cardiac valves was positive for Bartonella, and DNA sequencing of PCR amplicons identified Bartonella quintana. Patients received treatment with doxycycline/rifampin or doxycycline/gentamicin. Conclusion: Clinicians should consider Bartonella endocarditis as a differential diagnosis in patients who fit elements of the Duke Criteria, as well as having a history of homelessness and alcoholism.