Prevalence and Impact on Mortality of Colonization and Super-Infection by Carbapenem-Resistant Gram-Negative Organisms in COVID-19 Hospitalized Patients

BACKGROUND

The relationship between superinfection by multidrug-resistant Gram-negative bacteria and mortality among SARS-CoV-2 hospitalized patients is still unclear. Carbapenem-resistant Acinetobacter baumannii and carbapenemase-producing Enterobacterales are among the most frequently isolated species when it comes to hospital-acquired superinfections among SARS-CoV-2 patients.

METHODS

Herein, a retrospective study was carried out using data from adult patients hospitalized for COVID-19. The interaction between in-hospital mortality and rectal carriage and superinfection by carbapenemase-producing Enterobacterales and/or carbapenem-resistant Acinetobacter baumannii was assessed.

RESULTS

The incidence of KPC-producing Klebsiella pneumoniae and/or carbapenem-resistant Acinetobacter baumannii rectal carriage was 30%. Bloodstream infection and/or pneumonia due to KPC-producing Klebsiella pneumoniae and/or carbapenem-resistant Acinetobacter baumannii occurred in 20% of patients. A higher Charlson comorbidity index (OR 1.41, 95% CI 1.24-1.59), being submitted to invasive mechanical ventilation/ECMO ≥ 96 h (OR 6.34, 95% CI 3.18-12.62), being treated with systemic corticosteroids (OR 4.67, 95% CI 2.43-9.05) and having lymphopenia at the time of admission (OR 0.54, 95% CI 0.40-0.72) were the features most strongly associated with in-hospital mortality.

CONCLUSIONS

Although KPC-producing Klebsiella pneumoniae and/or carbapenem-resistant Acinetobacter baumannii rectal carriage, and/or bloodstream infection/pneumonia were diagnosed in a remarkable percentage of COVID-19 patients, their impact on in-hospital mortality was not significant. Further studies are needed to assess the burden of antimicrobial resistance as a legacy of COVID-19 in order to identify future prevention opportunities.

Rectal carriage of extended-spectrum β-lactamase-producing Enterobacteriales among neonates admitted into a special care baby unit, southwest Nigeria

BACKGROUND

The intestinal microbiota of neonates can be colonised by extended-spectrum β-lactamase-producing Enterobacteriales (ESBL-PE) with the risks of subsequent infections. The antimicrobial resistance profile of the gut flora of neonates is not well defined in Nigeria. This study determined the burden of rectal carriage of ESBL-PE among neonates.

METHODS

We conducted a prospective longitudinal study among neonates admitted into a tertiary hospital from September 2019 to November 2019. Stools were sampled at admission and weekly until exit and processed by standard laboratory methods including polymerase chain reaction to identify ESBL genes. The ESBL-PE colonisation period prevalence at admission and acquisition rate were determined.

RESULTS

The period prevalence of the ESBL-PE colonisation and acquisition rate were 46.5% (59/127) and 34.6% (36/104), respectively. Prolonged rupture of the amniotic membrane (PROM; >24 h; p=0.004, odds ratio [OR] 0.297), number of neonates on admission in the same room (p<0.001, OR 0.053) and presence of an ESBL-PE colonisers (p=0.004, OR 0.272) were independent risk factors for ESBL-PE rectal colonisation. ESBL-PE colonisation did not correlate with mortality (Fisher's exact test 1.342, p=0.196).

CONCLUSIONS

The rate of ESBL-PE neonatal rectal colonisation is high in our settings and this underscores the need for a review of neonatal admission protocols, embracing of antibiotic stewardship in the management of PROM, resistance surveillance and implementation of infection prevention and control in the neonatal unit.

Incidence and Time-to-Onset of Carbapenemase-Producing Enterobacterales (CPE) Infections in CPE Carriers: a Retrospective Cohort Study

This study aimed to assess the proportion of carbapenemase-producing Enterobacterales (CPE) infections among all infectious episodes in CPE carriers, compare the time-to-onset of CPE infections with that of other infections, assess the mortality of patients with CPE infections, and identify risk factors for CPE infections in CPE carriers. A retrospective cohort study was performed over a 10-year period in our University Hospital, and 274 CPE carriers were identified. All infectious episodes within the first 6 months following the diagnosis of CPE rectal carriage were considered. Risk factor analysis for CPE infections in CPE carriers was performed by univariate and multivariate analyses. This study revealed an incidence of 24.1% (66/274) of CPE infection within 6 months of CPE carriage diagnosis. The 28-day all-cause mortality due to CPE infections was 25.7%. CPE infections represented 52.6% (70/133) of all infectious episodes in CPE carriers in the first 6 months following CPE carriage detection, and these significantly occurred earlier than non-CPE infections, with a median time of 15 versus 51 days, respectively (P < 0.01). Based on the multivariate analysis, prior neurological disease was the only risk factor associated with CPE infections in CPE carriers. CPE infections have an early onset, accounting for a large proportion of infections in CPE carriers, and are associated with high mortality. IMPORTANCE Carbapenemase-producing Enterobacterales (CPE) infections are emerging infections and may represent a therapeutic challenge, while effective antibiotic therapy is likely to be delayed. We aimed to assess the proportion of CPE infections in CPE carriers and to identify risk factors of CPE infections among this population that could guide empirical antibiotic therapy. We showed that CPE infections are frequent in CPE carriers, have an early onset after CPE carriage diagnosis, and represent a significant proportion of all infectious episodes in CPE carriers. No significant risk factors for CPE infections could be identified. Overall, this study suggests that empirical antibiotic treatment covering CPE might be initiated in CPE carriers at least in the first month after its diagnosis and in severe infections due to the high frequency and early occurrence of CPE infections in these patients.

Rectal colonization with multidrug-resistant gram-negative bacteria in patients with hematological malignancies: a prospective study

OBJECTIVES

To investigate the risk factors for rectal colonization with carbapenem-resistant Enterobacteriaceae (CRE) and extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-E) in hematological malignant patients with febrile neutropenia (FN); rate of rectal colonization and infection/colonization with CRE and ESBL-E; whether empirical treatment can be revised.

METHODS

Adult patients receiving chemotherapy were included. Rectal swab cultures of patients were screened for CRE and ESBL-E using selective chromogenic agars.

RESULTS

Fifty-seven FN episodes of 57 patients were studied. Rectal colonization rates were 40.4% (23/57) and 8.8% (5/57) for ESBL-E and CRE, respectively. ESBL-E bacteremia was diagnosed in 2 (8.6%) ESBL-E colonized patients, while CRE bacteremia was detected in 1 (20%) CRE colonized patient. Amikacin (100%) and carbapenem (93%) were the most effective antibiotics against gram-negative enteric bacteria. Beta-lactam usage within the last 3 months was a significant risk factor for ESBL-E colonization.

CONCLUSIONS

For the treatment of FN patients either colonized with ESBL-E or having significant risk factors for ESBL-E infection, aminoglycoside containing combinations may become an alternative to carbapenems due to their high sensitivity rates. When CRE colonized hematological cancer patients develop FN or if they are hemodynamically unstable, CRE covering empiric antibiotherapy should be preferred due to high mortality rates of CRE bacteremia.

Risk Factors for Subsequential Carbapenem-Resistant Klebsiella pneumoniae Clinical Infection Among Rectal Carriers with Carbapenem-Resistant Klebsiella pneumoniae

Purpose

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection has become a critical clinical concern for its high mortality. Rectal carriage of CRKP has been reported playing an important role in CRKP infection; however, the extent to which carrier develops clinical CRKP infection is unclear. This study aimed to identify risk factors for developing subsequential CRKP clinical infection in rectal carriers with CRKP.

Patients and Methods

Patients were screened for rectal carriage of CRKP in a tertiary university hospital; then, rectal CRKP carriers were divided into case group (those who developed subsequential clinical infection) and control group. Demographics, comorbid conditions, invasive procedures, antimicrobial exposure and other clinical parameters of those two groups were compared and analyzed using univariate and multivariate logistic regression analyses. Antimicrobial susceptibility profile and carbapenemase phenotype/genotype of those CRKP isolates were determined. MLST was applied to elucidate the molecular epidemiology of rectal CRKP isolates and clinical infection ones.

Results

Eight hundred and thirty-five patients were screened for rectal CRKP carriage. A total of 62 CRKP rectal carriers were identified; among them, 37.1% (23/62) developed CRKP clinical infection. CRKP isolates were resistant to most of the tested antimicrobial agents. ST11 was the dominant MLST type in rectal CRKP isolates (71.0%), and all the 23 clinical infection isolates were ST11. Multivariate analysis revealed that admission to the intensive care unit (ICU) (OR, 6.753; P=0.006), being in coma condition (OR, 11.085; P=0.015) and receiving central venous catheter (OR, 8.628; P=0.003) were independent risk factors for progressing to subsequential CRKP infection among those rectal carriers.

Conclusion

This study identified independent risk factors for developing subsequential CRKP clinical infection among CRKP rectal carriers, with being in coma condition as a new finding. It would help clinician target those high-risk rectal CRKP-colonized patients for prevention of subsequential clinical infection.

The use of predictive scores in the management of patients with carbapenem-resistant Klebsiella pneumoniae infection

INTRODUCTION

Carbapenem-resistant Klebsiella pneumoniae (CR-KP) infections are associated with high morbidity and mortality rates. A therapeutic approach based on the patient risk stratification could improve outcome and avoid antibiotic misuse. Areas covered: English literature search, from 2008 to 2018, was done using PubMed database. Risk factors for developing CR-KP infection in several settings were reviewed. Since, rectal carriage was a main risk factor for developing infection, we revised in deep clinical score to predict infection among colonized patients. Furthermore, we investigated overall and treatment-related risk factors for poor outcome in patients with CR-KP infection, in particular the carbapenem producing Enterobacteriacieae (CPE)-INCREMENT score. Finally, an algorithm, based on such scores, for the therapeutic management of patients with CR-KP colonization was commented. Expert opinion: The therapeutic approach analyzed in this review could help physicians to avoid antibiotic overuse as well as to start promptly with the most appropriate antibiotic regimen. However, it has to be validated in further studies, mainly among special population such as immunocompromised patients. The availability of new drugs, fast microbiology, and analysis of gut microbiome could significantly improve the management of CR-KP colonized and/or infected patients.