Molecular Surveillance of Carbapenem-Resistant Gram-Negative Bacteria in Liver Transplant Candidates

Epidemiology and Prevention of Early Infections by Multi-Drug-Resistant Organisms in Adults Undergoing Liver Transplant: A Narrative Review

Invasive bacterial infections are a leading cause of morbidity and mortality after liver transplant (LT), especially during the first months after LT, and infections due to multi-drug-resistant organisms (MDRO) are increasing in this setting. Most of the infections in patients in intensive care unit arise from the endogenous microflora and, for this reason, pre-LT MDRO rectal colonization is a risk factor for developing MDRO infections in the post-LT. Moreover, the transplanted liver may carry an increased risk of MDRO infections due to organ transportation and preservation, to donor intensive care unit stay and previous antibiotic exposure. To date, little evidence is available about how MDRO pre-LT colonization in donors and recipients should address LT preventive and antibiotic prophylactic strategies, in order to reduce MDRO infections in the post-LT period. The present review provided an extensive overview of the recent literature on these topics, with the aim to offer a comprehensive insight about the epidemiology of MDRO colonization and infections in adult LT recipients, donor-derived MDRO infections, possible surveillance, and prophylactic strategies to reduce post-LT MDRO infections.

Colonization with Carbapenem-Resistant Enterobacteriaceae Contributes to Unfavorable Outcomes in End-Stage Liver Disease Patients

Carbapenem-resistant Enterobacteriaceae (CRE) are the highest priority pathogens of the World Health Organization, and their prevalence in end-stage liver disease (ESLD) patients is increasing. CRE colonization is an independent risk factor for CRE infections. We aimed to assess risk factors and explore the relationship between CRE colonization, infection, and prognosis in patients with ESLD. A total of 311 patients with ESLD were screened for CRE colonization by fecal swabs from October 2020 to January 2022. Antimicrobial susceptibility was tested using the broth microdilution method. Carbapenem resistance genes, multilocus sequence type, and capsular serotype were analyzed by polymerase chain reaction (PCR). Seventeen CRE strains were detected, among which the most common was Klebsiella pneumoniae. The CRE colonization rate was 5.5%. Artificial liver support was an independent risk factor for CRE colonization. Compared to the non-CRE colonization group, the colonization group had a higher incidence of CRE infection and a worse prognosis. Furthermore, these strains were not closely related, and all were sensitive to polymyxin and tigecycline. There was a high colonization rate in ESLD patients, and colonization strains were highly diverse. CRE colonization deserves attention in these patients, especially when treated with artificial liver support.

Interprofessional Collaboration between ICU Physicians, Staff Nurses, and Hospital Pharmacists Optimizes Antimicrobial Treatment and Improves Quality of Care and Economic Outcome

(1) Background: Antibiotic resistance is a worldwide health threat. The WHO published a global strategic plan in 2001 to contain antimicrobial resistance. In the following year, a workshop identified crucial barriers to the implementation of the strategy, e.g., underdeveloped health infrastructures and the scarcity of valid data as well as a lack of implementation of antibiotic stewardship (ABS) programs in medical curricula. Here, we show that interprofessional learning and education can contribute to the optimization of antibiotic use and preserving antibiotic effectiveness. We have initiated interprofessional rounds on a medical intensive care unit (MICU) with a focus on gastroenterology, hepatology, infectious diseases, endocrinology, and liver transplantation. We integrated ICU physicians, hospital pharmacists, nursing staff, and medical students as well as students of pharmacy to broaden the rather technical concept of ABS with an interprofessional approach to conceptualize awareness and behavioral change in antibiotic prescription and use. Methods: Clinical performance data and consumption figures for antibiotics were analyzed over a 10-year period from 2012 to 2021. The control period covered the years 2012–2014. The intervention period comprised the years 2015–2021, following the implementation of an interprofessional approach to ABS at a MICU of a German university hospital. Data from the hospital pharmacy, hospital administration, and hospital information system were included in the analyses. A specific electronic platform was developed for the optimization of documentation, interprofessional learning, education, and sustainability. The years 2020 and 2021 were analyzed independently due to the SARS-CoV-2 pandemic and the care of numerous COVID-19 patients at the MICU. Results: Implementation of an interprofessional ABS program resulted in the optimization of antibiotic management at the MICU. The suggestions of the hospital pharmacist for optimization can be divided into the following categories (i) indication for and selection of therapy (43.6%), (ii) optimization of dosing (27.6%), (iii) drug interactions (9.4%), (iv) side effects (4.1%), and (v) other pharmacokinetic, pharmacodynamic, and pharmacoeconomic topics (15.3%). These suggestions were discussed among the interprofessional team at the MICU; 86.1% were consequently implemented and the prescription of antibiotics was changed. In addition, further analysis of the intensive care German Diagnosis Related Groups (G-DRGs) showed that the case mix points increased significantly by 31.6% during the period under review. Accordingly, the severity of illness of the patients treated at the ICU as measured by the Simplified Acute Physiology Score (SAPS) II increased by 21.4% and the proportion of mechanically ventilated patients exceeded 50%. Antibiotic spending per case mix point was calculated. While spending was EUR 60.22 per case mix point in 2015, this was reduced by 42.9% to EUR 34.37 per case mix point by 2019, following the implementation of the interprofessional ABS program on the MICU. Through close interprofessional collaboration between physicians, hospital pharmacists, and staff nurses, the consumption of broad-spectrum antibiotics, e.g., carbapenems, was significantly reduced, thus improving patient care. In parallel, the case mix and case mix index increased. Thus, the responsible use of resources and high-performance medicine are not contradictory. In our view, close interprofessional and interdisciplinary collaboration between physicians, pharmacists, and nursing staff will be of outstanding importance in the future to prepare health care professionals for global health care to ensure that the effectiveness of our antibiotics is preserved.

Contemporary diagnostics for medically relevant fastidious microorganisms belonging to the genera Anaplasma, Bartonella, Coxiella, Orientia, and Rickettsia

Many of the human infectious pathogens—especially the zoonotic or vector-borne bacteria—are fastidious organisms that are difficult to cultivate because of their strong adaption to the infected host culminating in their near-complete physiological dependence on this environment. These bacterial species exhibit reduced multiplication rates once they are removed from their optimal ecological niche. This fact complicates the laboratory diagnosis of the disease and hinders the detection and further characterization of the underlying organisms, e.g. at the level of their resistance to antibiotics due to their slow growth. Here, we describe the current state of microbiological diagnostics for five genera of human pathogens with a fastidious laboratory lifestyle. For Anaplasma spp., Bartonella spp., Coxiella burnetii, Orientia spp. and Rickettsia spp., we will summarize the existing diagnostic protocols, the specific limitations for implementation of novel diagnostic approaches and the need for further optimization or expansion of the diagnostic armamentarium. We will reflect upon the diagnostic opportunities provided by new technologies including mass spectrometry and next-generation nucleic acid sequencing. Finally, we will review the (im)possibilities of rapidly developing new in vitro diagnostic tools for diseases of which the causative agents are fastidiously growing and therefore hard to detect.