Investigation and Analysis of the Colonization and Prevalence of Carbapenem-Resistant Enterobacteriaceae in Pediatric Liver Transplant Recipients

Update on Epidemiology and Outcomes of Infection in Pediatric Organ Transplant Recipients

Pediatric solid organ transplant (SOT) recipients are at risk for infection following transplantation. Data from adult SOT recipients are often used to guide prevention and treatment of infections associated with organ transplantation in children. This article highlights key recent pediatric SOT-specific publications for an array of infectious complications of organ transplantation. Attention is given to areas of need for future study.

Risk factors for carbapenem-resistant Enterobacterales infection among hospitalized patients with previous colonization

BACKGROUND

We aimed to identify the risk factors for subsequent carbapenem-resistant Enterobacterales (CRE) infections in patients with initial rectal colonization with CRE.

METHODS

We conducted a retrospective case-control study on inpatients with rectal CRE colonization between January 2019 and December 2020. Clinical and microbiological data were extracted from hospital patients' medical records and the clinical microbiology laboratory. Risk factors were assessed and compared between patients with CRE colonization who had subsequent infections and those who did not have infections.

RESULTS

Among 1064 patients screened for CRE, we enrolled 205 patients with rectal CRE colonization. Among the 205 colonized bacteria, 78.5% were Klebsiella pneumoniae, with 62.9% of them producing Klebsiella pneumoniae carbapenemase (KPC). Multivariate logistic regression analysis revealed that more than three times hospitalization (p = 0.026), being in a coma (p = 0.019), and exposure to carbapenems (p = 0.015) were independent risk factors for CRE clinical infection among CRE rectal carriers.

CONCLUSION

This is the first study to report that more than three times hospitalization is an independent risk factor for subsequent CRE clinical infection in CRE intestinal carriers. Carbapenem-resistant Klebsiella pneumoniae is the most important species isolated from hospitalized CRE rectal carriers and is the most common cause of subsequent infections.

Ceftazidime-Avibactam as Salvage Therapy in Pediatric Liver Transplantation Patients with Infections Caused by Carbapenem-Resistant Enterobacterales

Objective

There are few therapeutic options for infections caused by carbapenem-resistant Enterobacterales (CRE) in children following liver transplantation. Ceftazidime-avibactam (CAZ-AVI), a recently licensed antibacterial in China, was utilized as a salvage therapy against CRE in our center, and its efficacy and safety were therefore assessed.

Methods

The retrospective, observational study was conducted at the First Affiliated Hospital of Zhejiang University. Pediatric liver transplantation patients (≤12 years) who received CAZ-AVI as a salvage therapy against CRE infections were included from January 2020 to December 2021. Clinical success and all-cause death during hospitalization were the primary outcomes. Recurrence of infection, drug-related adverse events, and changes in inflammatory biomarkers were collected.

Results

Six children were enrolled, with a median age of 10.1 (interquartile range (IQR) 5.5–13.8) months. Primary intraperitoneal infections occurred in all patients, with five patients developing bloodstream infections. KPC carbapenemases were detected in most isolates, and the susceptibility results showed general sensitivity to tigecycline, polymyxin B, and CAZ-AVI. Tigecycline-based therapy was taken as the initial treatment and withdrawn because of clinical failure (5 cases) or cholestasis (1 case). After CRE infection, the median time to convert to CAZ-AVI was 7.5 (IQR 7.0–8.8) days, and the median CAZ-AVI treatment length was 21.0 (IQR 20.3–28.5) days. Clinical success was achieved in all patients, with a zero percent all-cause death rate. No CRE infections recurred throughout hospitalization, and no resistance to CAZ-AVI was detected. Patients experienced vomiting (1/6), skin rash (1/6), and a transient increase in cystatin C (2/6), γ-glutamyltransferase (2/6), and alkaline phosphatase (3/6).

Conclusion

CAZ-AVI was shown to be a successful salvage treatment for CRE infection in pediatric liver transplant recipients, with minor and temporary drug-related side effects.

Impact of Two Antibiotic Therapies on Clinical Outcome and Gut Microbiota Profile in Liver Transplant Paediatric Candidates Colonized by Carbapenem-Resistant Klebsiella pneumoniae CR-KP

Colonization by multidrug-resistant (MDR) organisms in liver transplant (LT) candidates significantly affects the LT outcome. To date, consensus about patient management is lacking, including microbiological screening indications. This pilot study aimed to evaluate the impact of carbapenem-resistant Klebsiella pneumoniae (CR-KP) colonization in LT paediatric candidates to enable optimal prevention and therapeutic strategies that exploit both clinical and microbiological approaches. Seven paediatric patients colonized by CR-KP were evaluated before and until one-year post LT. At the time of the transplant, patients were stratified based on antibiotic (ATB) prophylaxis into two groups: ‘standard ATB’ (standard ATB prophylaxis), and ‘targeted ATB’ (MDR antibiogram-based ATB prophylaxis). Twenty-eight faecal samples were collected during follow-up and used for MDR screening and gut microbiota 16S rRNA-based profiling. Post-transplant hospitalization duration was comparable for both groups. With the exception of one patient, no serious infections and/or complications, nor deaths were recorded. A progressive MDR decontamination was registered. In the ‘standard ATB’ group, overall bacterial richness increased. Moreover, 6 months after LT, Lactobacillus and Bulleidia were increased and Enterobacteriaceae and Klebsiella spp. were reduced. In the ‘targeted ATB’ group Klebsiella spp., Ruminococcus gnavus, Erysipelotrichaceae, and Bifidobacterium spp. were increased 12 months after LT. In conclusion, both antibiotics prophylaxis do not affect nor LT outcomes or the risk of intestinal bacterial translocation. However, in the ‘standard ATB’ group, gut microbiota richness after LT was increased, with an increase of beneficial lactic acid- and short-chain fatty acids (SCFA)-producing bacteria and the reduction of harmful Enterobacteriaceae and Klebsiella spp. It could therefore be appropriate to administer standard prophylaxis, reserving the use of ATB-based molecules only in case of complications.