Off-label Use of Ceftazidime/Avibactam in Neonatal Intensive Care Unit: A Real-life Experience and Literature Review

BACKGROUND

Multi/extensively drug-resistant bacterial infections have recently increased and new antimicrobial options are needed for difficult-to-treat infections. Ceftazidime/avibactam (CZA) has been approved for patients 3 months to 18 years of age, but real-life data on its off-label use in neonates and young infants are still scarce.

MATERIALS

We report demographic, clinical and microbiologic data as well as outcome and safety of all cases of infants treated with CZA between January 1, 2021 and September 30, 2022 in a tertiary neonatal intensive care unit. We also review all neonatal cases previously reported.

RESULTS

Twenty-one patients [17 males, with median gestational age 29 +2 (IQR 6 +6 ) weeks] received 31 CZA courses at a dose of 20-50 mg/kg/dose of ceftazidime q8h for suspected or proved multi/extensively drug-resistant infections. Median postnatal age at the onset of treatment was 44 days (IQR: 94 days). Twelve bacteremias, 2 urinary tract infections and 1 ventilator-acquired pneumonia were recorded. Twelve (39%) treatments were targeted, while 19 (61%) were empirically started due to known colonization with Klebsiella pneumoniae carbapenemase-producing Gram-negative bacteria. All patients had received multiple antibiotics prior and concomitantly with CZA. The most common pathogen identified at targeted administrations was carbapenem-resistant Klebsiella pneumoniae (83%). No serious adverse events attributed to the drug were detected. Twenty-one courses of CZA administration to 20 neonates with a median gestational age of 28.5 (IQR 3.5) weeks were previously reported without significant related adverse events.

CONCLUSIONS

Favorable clinical and microbiologic responses in neonatal intensive care unit patients treated with CZA off-label were observed without significant and unexpected adverse events in critically ill neonates.

Neonatal Bloodstream Infection with Ceftazidime-Avibactam-Resistant blaKPC-2-Producing Klebsiella pneumoniae Carrying blaVEB-25

BACKGROUND

Although ceftazidime/avibactam (CAZ/AVI) has become an important option for treating adults and children, no data or recommendations exist for neonates. We report a neonatal sepsis case due to CAZ/AVI-resistant blaKPC-2-harboring Klebsiella pneumoniae carrying blaVEB-25 and the use of a customized active surveillance program in conjunction with enhanced infection control measures.

METHODS

The index case was an extremely premature neonate hospitalized for 110 days that had been previously treated with multiple antibiotics. Customized molecular surveillance was implemented at hospital level and enhanced infection control measures were taken for early recognition and prevention of outbreak. Detection and identification of blaVEB-25 was performed using next-generation sequencing.

RESULTS

This was the first case of a bloodstream infection caused by KPC-producing K. pneumoniae that was resistant to CAZ/AVI without the presence of a metalo-β-lactamase in the multiplex PCR platform in a neonate. All 36 additional patients tested (12 in the same NICU and 24 from other hospital departments) carried wild-type blaVEB-1 but they did not harbor blaVEB-25.

CONCLUSION

The emergence of blaVEB-25 is signal for the horizontal transfer of plasmids at hospital facilities and it is of greatest concern for maintaining a sharp vigilance for the surveillance of novel resistance mechanisms. Molecular diagnostics can guide appropriate antimicrobial therapy and the early implementation of infection control measures against antimicrobial resistance.

Use of Newer and Repurposed Antibiotics against Gram-Negative Bacteria in Neonates

Antimicrobial resistance has become a significant public health problem globally with multidrug resistant Gram negative (MDR-GN) bacteria being the main representatives. The emergence of these pathogens in neonatal settings threatens the well-being of the vulnerable neonatal population given the dearth of safe and effective therapeutic options. Evidence from studies mainly in adults is now available for several novel antimicrobial compounds, such as new β-lactam/β-lactamase inhibitors (e.g., ceftazidime-avibactam, meropenem-vaborbactam, imipenem/cilastatin-relebactam), although old antibiotics such as colistin, tigecycline, and fosfomycin are also encompassed in the fight against MDR-GN infections that remain challenging. Data in the neonatal population are scarce, with few clinical trials enrolling neonates for the evaluation of the efficacy, safety, and dosing of new antibiotics, while the majority of old antibiotics are used off-label. In this article we review data about some novel and old antibiotics that are active against MDR-GN bacteria causing sepsis and are of interest to be used in the neonatal population.

Genetic Characterization of Carbapenem-Resistant Klebsiella pneumoniae Clinical Isolates in a Tertiary Hospital in Greece, 2018-2022

BACKGROUND

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a serious public health issue. The study aimed to identify the antimicrobial resistance and accessory genes, the clonal relatedness, and the evolutionary dynamics of selected CRKP isolates recovered in an adult and pediatric intensive care unit of a tertiary hospital in Greece.

METHODS

Twenty-four CRKP isolates recovered during 2018-2022 were included in the study. Next-generation sequencing was performed using the Ion Torrent PGM Platform. The identification of the plasmid content, MLST, and antimicrobial resistance genes, as well as the comparison of multiple genome alignments and the identification of core genome single-nucleotide polymorphism sites, were performed using various bioinformatics software.

RESULTS

The isolates belonged to eight sequence types: 11, 15, 30, 35, 39, 307, 323, and 512. A variety of carbapenemases (KPC, VIM, NDM, and OXA-48) and resistance genes were detected. CRKP strains shared visually common genomic regions with the reference strain (NTUH-K2044). ST15, ST323, ST39, and ST11 CRKP isolates presented on average 17, 6, 16, and 866 recombined SNPs, respectively. All isolates belonging to ST15, ST323, and ST39 were classified into distinct phylogenetic branches, while ST11 isolates were assigned to a two-subclade branch. For large CRKP sets, the phylogeny seems to change approximately every seven SNPs.

CONCLUSIONS

The current study provides insight into the genetic characterization of CRKP isolates in the ICUs of a tertiary hospital. Our results indicate clonal dispersion of ST15, ST323, and ST39 and highly diverged ST11 isolates.

Evaluation of Five Host Inflammatory Biomarkers in Early Diagnosis of Ventilator-Associated Pneumonia in Critically Ill Children: A Prospective Single Center Cohort Study

Background: Early diagnosis of ventilator-associated pneumonia (VAP) remains a challenge due to subjective clinical criteria and the low discriminative power of diagnostic tests. We assessed whether rapid molecular diagnostics in combination with Clinically Pulmonary Index Score (CPIS) scoring, microbiological surveillance and biomarker measurements of PTX-3, SP-D, s-TREM, PTX-3, IL-1β and IL-8 in the blood or lung could improve the accuracy of VAP diagnosis and follow-up in critically ill children. Methods: A prospective pragmatic study in a Pediatric Intensive Care Unit (PICU) was conducted on ventilated critically ill children divided into two groups: high and low suspicion of VAP according to modified Clinically Pulmonary Index Score (mCPIS). Blood and bronchial samples were collected on days 1, 3, 6 and 12 after event onset. Rapid diagnostics were used for pathogen identification and ELISA for PTX-3, SP-D, s-TREM, IL-1β and IL-8 measurements. Results: Among 20 enrolled patients, 12 had a high suspicion (mCPIS > 6), and 8 had a low suspicion of VAP (mCPIS < 6); 65% were male; and 35% had chronic disease. IL-1β levels at day 1 correlated significantly with the number of mechanical ventilation days (r_s = 0.67, p < 0.001) and the PICU stay (r = 0.66; p < 0.002). No significant differences were found in the levels of the other biomarkers between the two groups. Mortality was recorded in two patients with high VAP suspicion. Conclusions: PTX-3, SP-D, s-TREM, IL-1β and IL-8 biomarkers could not discriminate patients with a high or low suspicion of VAP diagnosis.

Modifiable risk factors associated with later gut decolonization of carbapenem-resistant Gram-negative bacteria in children: A prospective cohort study

BACKGROUND

Nosocomial infections caused by carbapenem-resistant gram-negative bacteria (CRGNB) are associated with increased mortality and prolonged hospitalization; thus, later CRGNB-decolonization has significant clinical and public health implications.

AIM

We investigated modifiable/ non-modifiable risk factors for CRGNB-later gut decolonization in children.

METHODS

We included CRGNB-carriers (1day-16years old), hospitalized in a tertiary-level hospital (2018-2019). Upon CRGNB-carriage detection, rectal-swab cultures were taken weekly, if patients were hospitalized and monthly after discharge for 12 months. CRGNB-decolonization was defined as three consecutive negative rectal-swab cultures obtained ≥1 week apart. Modifiable (treatment administered/medical devices) and non-modifiable (age/gender/comorbidities) risk factors were recorded. Cox regression for later CRGNB-decolonization was performed.

FINDINGS

One hundred thirty CRGNB-carriers were recorded. After 12 months, 5.4% remained carriers. Risk factors for later decolonization were immunosuppression (HR: 0.52, 95%CI: 0.31-0.87), carbapenems (HR: 0.52, 95%CI: 0.30-0.91), proton-pump inhibitors (PPIs) (HR: 0.39, 95%CI: 0.24-0.64) and their duration of use, duration of hospitalization (HR: 0.90, 95%CI: 0.81-0.92, per 10 days), number of re-admissions (HR: 0.90, 95%CI: 0.86-0.96), abdominal surgery (HR: 0.33, 95%CI: 0.17-0.65), urinary catheter (HR: 0.42, 95%CI: 0.24-0.76) and duration of steroid administration (HR: 0.86, 95%CI: 0.84-0.88, per 10 days).

CONCLUSIONS

Carbapenems, PPIs and their duration of use, duration of steroids use, immunosuppression, urinary catheter, re-admissions, duration of hospitalization, and abdominal surgery are associated with later CRGNB-decolonization among children. Paediatric patients at risk of later decolonization should be under targeted screening and preemptive contact precautions. Known carriers at risk of later CRGNB-decolonization should be under meticulously applied contact precautions for longer durations.

Epidemiology of Mucormycosis in Greece; Results from a Nationwide Prospective Survey and Published Case Reports

Mucormycosis has emerged as a group of severe infections mainly in immunocompromised patients. We analysed the epidemiology of mucormycosis in Greece in a multicentre, nationwide prospective survey of patients of all ages, during 2005–2022. A total of 108 cases were recorded. The annual incidence declined after 2009 and appeared stable thereafter, at 0.54 cases/million population. The most common forms were rhinocerebral (51.8%), cutaneous (32.4%), and pulmonary (11.1%). Main underlying conditions were haematologic malignancy/neutropenia (29.9%), haematopoietic stem cell transplantation (4.7%), diabetes mellitus (DM) (15.9%), other immunodeficiencies (23.4%), while 22.4% of cases involved immunocompetent individuals with cutaneous/soft-tissue infections after motor vehicle accident, surgical/iatrogenic trauma, burns, and injuries associated with natural disasters. Additionally, DM or steroid-induced DM was reported as a comorbidity in 21.5% of cases with various main conditions. Rhizopus (mostly R. arrhizus) predominated (67.1%), followed by Lichtheimia (8.5%) and Mucor (6.1%). Antifungal treatment consisted mainly of liposomal amphotericin B (86.3%), median dose 7 mg/kg/day, range 3–10 mg/kg/day, with or without posaconazole. Crude mortality was 62.8% during 2005–2008 but decreased significantly after 2009, at 34.9% (p = 0.02), with four times fewer haematological cases, fewer iatrogenic infections, and fewer cases with advanced rhinocerebral form. The increased DM prevalence should alert clinicians for timely diagnosis of mucormycosis in this patient population.

Antimicrobial Stewardship Programs in PICU Settings: A Systematic Review

OBJECTIVES

Development of antimicrobial stewardship programs (ASPs) is strategy for prevention and management of emergence of antimicrobial-resistant organisms. In this study, we systematically reviewed the literature on antimicrobial stewardship interventions in PICUs and analyzed approaches, structure, implementation, and outcomes of the ASPs.

DATA SOURCES

PubMed and Scopus databases were systematically searched for studies published from January 1, 2007, to December 31, 2020, reporting interventions on judicious use of antimicrobials in PICUs (last search performed February 28, 2021).

DATA SELECTION

Studies that evaluated an intervention in a PICU setting or both in PICU and other settings and reported separate results for PICU were eligible for full-text review. Studies that had implemented stewardship in the entire hospital, including the PICU, but without presenting dedicated PICU data were excluded from the analysis.

DATA EXTRACTION

The strategy of intervention, structure of ASP team, implementation, and outcomes were assessed with a checklist tool for all studies included in the analysis. Risk of bias was assessed with the Cochrane Risk-of-Bias in Nonrandomized studies of Interventions tool.

DATA SYNTHESIS

Thirteen articles were found: 11 that applied ASP in PICUs, and two at hospital level. All PICU-dedicated ASPs applied a multimodal intervention combining strategies simultaneously; audit with feedback (6/11) and facility-specific clinical practice guidelines (7/11) were the most common strategies. A multidisciplinary team was formulated in all ASPs except for three biomarker-based interventions. Six of 11 studies included techniques to enhance behavior change and one implemented a behavior-based intervention. Antibiotic consumption was evaluated in all ASPs, cost in three of 11, antibiotic resistance in one of 11, length of hospitalization in six of 11, and mortality in eight of 11. All hospital-wide ASPs used audit with feedback in addition to facility-specific clinical practice guidelines and assessed antimicrobial consumption, expenditures, length of stay, and mortality.

CONCLUSIONS

The prevalence of ASPs in PICUs is limited, and few programs follow all of the currently available recommendations.

2011. Use of Biofire®Filmarray gastrointestinal panel on clinical decision making and infection control in a General Pediatric Department

Background

The new Biofire® Filmarray Gastrointestinal Panel (BFGI-BioMérieux, France) offers advantage against conventional cultures of gastrointestinal tract specimens with rapid detection and a broader pathogen identification. Aim of this study is to evaluate the use of BFGI and compare detection of pathogens in GI samples with conventional cultures in hospitalized children with gastroenteritis.

Methods

A retrospective study was conducted in a General Tertiary level Pediatric Department from Jan 2020 to Apr 2022. Children were included if an appropriate GI tract specimen was obtained for clinical evaluation and was assessed by BFGI. Results were compared with conventional cultures. Demographic, clinical, laboratory data, treatment and the effect of the BFGI on clinical decision making were analyzed.

Results

Fifty-eight children were included, 27(46%) females, with mean age 5.1 (IQR 9.35). Thirty-one (53%) had an underlying condition, or a prolonged hospital stay. All children had diarrhea, 44% had fever and 25% had vomits. The most common pathogens were Norovirus (8/58), Campylobacter (7/58) and Enteropathogenic Escherichia coli (EPEC, 6/58), followed by Clostridium difficile, Rotavirus and Salmonella spp. Five of the Norovirus cases were detected within a 10-day period, in children that were hospitalized for other reasons, indicating an intrahospital outbreak. In five patients there was a co-infection with 2 or more pathogens. In 35 patients a stool culture (salmonella and shigella) was performed. All cultures were negative. In 20 (57%) patients, culture results were in accordance with a negative BFGI, but in the rest 15 (42%) patients the PCR detected at least one pathogen. Only 17 patients were treated with antimicrobials, because of age &lt; 3 months or the severity of disease/ comorbidities. A macrolide was prescribed in all campylobacter cases (clarithromycin, 57%, azithromycin, 43%).

Conclusion

In this cohort of hospitalized patients with gastroenteritis, BFGI offered a rapid and more precise result, in comparison to cultures. It helped recognize a norovirus outbreak in the department and improve the infection control measures. Finally, it assisted the clinical decision making leading to more rational and targeted antibiotic administration.

Disclosures

All Authors: No reported disclosures.

Targeted Genotyping of MIS-C Patients Reveals a Potential Alternative Pathway Mediated Complement Dysregulation during COVID-19 Infection

Complement dysregulation has been documented in adults with COVID-19 and implicated in relevant pediatric inflammatory responses against SARS-CoV-2. We propose that signatures of complement missense coding SNPs associated with dysregulation could also be identified in children with multisystem inflammatory syndrome (MIS-C). We investigated 71 pediatric patients with RT-PCR validated SARS-CoV-2 hospitalized in pediatric COVID-19 care units (November 2020–March 2021) in three major groups. Seven (7) patients suffered from MIS-C (MIS-C group), 32 suffered from COVID-19 and were hospitalized (admitted group), whereas 32 suffered from COVID-19, but were sent home. All patients survived and were genotyped for variations in the C3, C5, CFB, CFD, CFH, CFHR1, CFI, CD46, CD55, MASP1, MASP2, MBL2, COLEC11, FCN1, and FCN3 genes. Upon evaluation of the missense coding SNP distribution patterns along the three study groups, we noticed similarities, but also considerably increased frequencies of the alternative pathway (AP) associated with SNPs rs12614 CFB, rs1061170, and rs1065489 CFH in the MIS-C patients. Our analysis suggests that the corresponding substitutions potentially reduce the C3b-inactivation efficiency and promote slower and weaker AP C3bBb pre-convertase assembly on virions. Under these circumstances, the complement AP opsonization capacity may be impaired, leading to compromised immune clearance and systemic inflammation in the MIS-C syndrome.

Changes in molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae in the intensive care units of a Greek hospital, 2018-2021

The spread of multi-drug resistant (MDR) Gram-negative bacteria, including Klebsiella pneumoniae, constitutes a global threat. The most frequent mechanism of acquired carbapenem resistance is the production of carbapenemases, especially KPC, NDM, VIM, IMP and OXA-48. We analyzed the epidemiological trend of carbapenem resistance genes of carbapenem-resistant K. pneumoniae (CRKP) strains isolated from critically ill patients in a Greek tertiary hospital. The study included 150 CRKP isolates collected from 116 (77.4%) patients hospitalized in the adult ICU and 17 (11.3%) each in the pediatric and the two neonatal ICUs between March 2018 and March 2021. Identification and antimicrobial susceptibility testing were performed using VITEK-2. A multiplex lateral flow immunoassay was used for the detection of carbapenemases, while the detection of bla VIM, bla KPC, bla NDM, bla IMP and bla OXA-48-like genes was achieved by multiplex PCR. The bla NDM was mainly detected in adults (54/116, 46.9%), while in children the most often detected gene was bla KPC (24/34, 70.6%). The predominant carbapenem resistance gene during 2018-2019 was bla KPC alone or in combination with bla VIM, reaching 44.4% in 2019, while during 2020-2021 the detection of bla NDM prevailed significantly, reaching 45.5 and 60.7% for 2020 and 2021, respectively. A shift in the molecular epidemiology of CRKP was seen during 2018-2021, which is probably associated with the recent excessive empiric use of newer antimicrobials. Surveillance studies and proper and strict implementation of infection control measures are highly needed to decrease the spread of MDR bacteria, including CRKP.

Early initiation of the respiratory syncytial virus season in 2021-2022, Greece

Respiratory syncytial virus (RSV) is the most common viral pathogen causing respiratory disease in the pediatric population. An unexpected sudden upsurge of RSV infections among children was observed in September 2021 in Greece. Forty-one rhinopharyngeal samples from children under the age of 2 years with confirmed RSV bronchiolitis were tested to identify the genotype(s) of the RSV strain(s). The children were hospitalized during September-November 2021 in three tertiary hospitals in northern Greece. A one-step RT-PCR which amplifies a fragment of the second hypervariable region of the G protein gene was applied. PCR products were sequenced, and phylogenetic analysis was performed. Most (80.5%) RSV cases were typed as RSV-A, with RSV-B accounting for 19.5% of cases. RSV-A and RSV-B sequences clustered within the ON1 and BA genotypes, respectively. Since the same genotypes were detected in cases observed during 2016-2018 in northern Greece, it was suggested that the early upsurge of infections was not related to the emergence of novel strain(s), but it was the result of the absence of immunity among children and their mothers due to the restriction measures taken during the COVID-19 pandemic in the previous RSV season. Awareness is needed to diagnose even the out-of-season RSV infections, while molecular epidemiology plays a key role in monitoring the efficacy of currently available therapeutics and for those under development. This article is protected by copyright. All rights reserved.

Optimised versus standard dosing of vancomycin in infants with Gram-positive sepsis (NeoVanc): a multicentre, randomised, open-label, phase 2b, non-inferiority trial

BACKGROUND

Vancomycin is the most widely used antibiotic for neonatal Gram-positive sepsis, but clinical outcome data of dosing strategies are scarce. The NeoVanc programme comprised extensive preclinical studies to inform a randomised controlled trial to assess optimised vancomycin dosing. We compared the efficacy of an optimised regimen to a standard regimen in infants with late onset sepsis that was known or suspected to be caused by Gram-positive microorganisms.

METHODS

NeoVanc was an open-label, multicentre, phase 2b, parallel-group, randomised, non-inferiority trial comparing the efficacy and toxicity of an optimised regimen of vancomycin to a standard regimen in infants aged 90 days or younger. Infants with at least three clinical or laboratory sepsis criteria or confirmed Gram-positive sepsis with at least one clinical or laboratory criterion were enrolled from 22 neonatal intensive care units in Greece, Italy, Estonia, Spain, and the UK. Infants were randomly assigned (1:1) to either the optimised regimen (25 mg/kg loading dose, followed by 15 mg/kg every 12 h or 8 h dependent on postmenstrual age, for 5 ± 1 days) or the standard regimen (no loading dose; 15 mg/kg every 24 h, 12 h, or 8 h dependent on postmenstrual age for 10 ± 2 days). Vancomycin was administered intravenously via 60 min infusion. Group allocation was not masked to local investigators or parents. The primary endpoint was success at the test of cure visit (10 ± 1 days after the end of actual vancomycin therapy) in the per-protocol population, where success was defined as the participant being alive at the test of cure visit, having a successful outcome at the end of actual vancomycin therapy, and not having a clinically or microbiologically significant relapse or new infection requiring antistaphylococcal antibiotics for more than 24 h within 10 days of the end of actual vancomycin therapy. The non-inferiority margin was -10%. Safety was assessed in the intention-to-treat population. This trial is registered at ClinicalTrials.gov (NCT02790996).

FINDINGS

Between March 3, 2017, and July 29, 2019, 242 infants were randomly assigned to the standard regimen group (n=122) or the optimised regimen group (n=120). Primary outcome data in the per-protocol population were available for 90 infants in the optimised group and 92 in the standard group. 64 (71%) of 90 infants in the optimised group and 73 (79%) of 92 in the standard group had success at test of cure visit; non-inferiority was not confirmed (adjusted risk difference -7% [95% CI -15 to 2]). Incomplete resolution of clinical or laboratory signs after 5 ± 1 days of vancomycin therapy was the main factor contributing to clinical failure in the optimised group. Abnormal hearing test results were recorded in 25 (30%) of 84 infants in the optimised group and 12 (15%) of 79 in the standard group (adjusted risk ratio 1·96 [95% CI 1·07 to 3·59], p=0·030). There were six vancomycin-related adverse events in the optimised group (one serious adverse event) and four in the standard group (two serious adverse events). 11 infants in the intention-to-treat population died (six [6%] of 102 infants in the optimised group and five [5%] of 98 in the standard group).

INTERPRETATION

In the largest neonatal vancomycin efficacy trial yet conducted, no clear clinical impact of a shorter duration of treatment with a loading dose was demonstrated. The use of the optimised regimen cannot be recommended because a potential hearing safety signal was identified; long-term follow-up is being done. These results emphasise the importance of robust clinical safety assessments of novel antibiotic dosing regimens in infants.

FUNDING

EU Seventh Framework Programme for research, technological development and demonstration.

1162. Antifungal Use in Immunocompromised Children in Europe: a 12-week Multicenter Modified Point prevalence Study (CALYPSO)

Background

While antifungal consumption in immunocompromised patients appears high, data on children are limited. We analyzed antifungal use in hospitalized immunocompromised children across Europe in order to better organize a European pediatric antifungal stewardship programs (pAFS).

Methods

A multicenter 12-wk modified point-prevalence study was conducted. All patients hospitalized in hematology-oncology (HO) or bone marrow/solid organ transplant (BMT/SOT) units across Europe and receiving systemic antifungals were included. Data on ward demographics and policies were collected once at the beginning; weekly ward and patient data were prospectively collected during the 12-wk study period and entered in REDCap. Systemic antifungals administered were recorded (doses, duration, reason for administration or discontinuation).

Results

Twenty-one HO and 10 BMT/SOT units from 18 hospitals in 11 European countries participated in the study and 572 antifungal prescriptions were recorded. The most common underlying conditions were: 69% malignancy (81% hematologic, 19% solid tumors), 20% BMT, 6% hematologic diseases except malignancy and 4% primary immunodeficiency. Indication of antifungals was prophylaxis for 439 (77%) and treatment for 133 (23%) prescriptions (62 empirical, 43 pre-emptive, 28 targeted). Most common reasons for empirical, pre-emptive and targeted treatment were antibiotic-resistant febrile neutropenia (52%), abnormalities on chest-CT with/without positive galactomannan (72%) and candidiasis (82%), respectively. For targeted treatment, the most frequent pathogens were C. albicans (50%), C. parapsilosis (11%) and A. fumigatus (11%). Overall, fluconazole and liposomal amphotericin B were the most frequently prescribed agents both for prophylaxis (31% and 21%) and treatment (32% and 23%). However, in BMT patients the most frequently prescribed antifungal agents were fluconazole or micafungin for prophylaxis and caspofungin and voriconazole for treatment (Table).

Antifungal agents used per underlying condition

Conclusion

Most systemic antifungal prescribing across European HO and BMT/SOT units is for prophylaxis, and fluconazole is the main antifungal prescribed. Results from this multicenter study can be a first step to guide a Europe-wide pAFS.

Disclosures

Emmanuel Roilides, MD, PhD, ECMM (Research Grant or Support, Other Financial or Material Support, ECMM grant for this study)

Aetiology of acute respiratory infection in preschool children requiring hospitalisation in Europe-results from the PED-MERMAIDS multicentre case-control study

Background

Both pathogenic bacteria and viruses are frequently detected in the nasopharynx (NP) of children in the absence of acute respiratory infection (ARI) symptoms. The aim of this study was to estimate the aetiological fractions for ARI hospitalisation in children for respiratory syncytial virus (RSV) and influenza virus and to determine whether detection of specific respiratory pathogens on NP samples was associated with ARI hospitalisation.

Methods

349 children up to 5 years of age hospitalised for ARI (following a symptom-based case definition) and 306 hospital controls were prospectively enrolled in 16 centres across seven European Union countries between 2016 and 2019. Admission day NP swabs were analysed by multiplex PCR for 25 targets.

Results

RSV was the leading single cause of ARI hospitalisations, with an overall population attributable fraction (PAF) of 33.4% and high seasonality as well as preponderance in younger children. Detection of RSV on NP swabs was strongly associated with ARI hospitalisation (OR adjusted for age and season: 20.6, 95% CI: 9.4 to 45.3). Detection of three other viral pathogens showed strong associations with ARI hospitalisation: influenza viruses had an adjusted OR of 6.1 (95% CI: 2.5 to 14.9), parainfluenza viruses (PIVs) an adjusted OR of 4.6 (95% CI: 1.8 to 11.3) and metapneumoviruses an adjusted OR of 4.5 (95% CI: 1.3 to 16.1). Influenza viruses had a PAF of 7.9%, PIVs of 6.5% and metapneumoviruses of 3.0%. In contrast, most other pathogens were found in similar proportions in cases and controls, including Streptococcus pneumoniae, which was weakly associated with case status, and endemic coronaviruses.

Conclusion

RSV is the predominant cause of ARI hospitalisations in young children in Europe and its detection, as well as detection of influenza virus, PIV or metapneumovirus, on NP swabs can establish aetiology with high probability. PAFs for RSV and influenza virus are highly seasonal and age dependent.

Management of osteoarticular fungal infections in the setting of immunodeficiency

Introduction: Osteoarticular fungal infections (OAFIs) complicate the clinical course of high-risk patients, including immunosuppressed individuals. Their management, however, despite being intricate, is governed by evidence arising from sub-optimal quality research, such as case series. Guidelines are scarce and when present result in recommendations based on low quality evidence. Furthermore, the differences between the management of immunocompromised and immunocompetent patients are not distinct. This is a narrative review after a literature search in PubMed, up to November 2019.Areas covered: The major fungal groups causing osteomyelitis and/or arthritis are Candida spp., Aspergillus spp., non-Aspergillus filamentous fungi, non-Candida yeasts and endemic dimorphic fungi. Their epidemiology is briefly analyzed with emphasis on immunodeficiency and other risk factors. Management of OAFIs includes appropriate antifungal drug therapy (liposomal amphotericin B, triazoles or echinocandins), local surgery and immunotherapy for primary immunodeficiencies. Cessation of immunosuppressive drugs is also mandated.Expert opinion: Management of OAFIs includes affordable and available options and approaches. However, research on therapeutic practices is urgently required to be further improved, due to the rarity of affected patients. Evolution is expected to translate into novel antifungal drugs, less invasive and precise surgical approaches and targeted enhancement of immunoregulatory pathways in defense of challenging fungal pathogens.

Meropenem vs standard of care for treatment of neonatal late onset sepsis (NeoMero1): A randomised controlled trial

Background

The early use of broad-spectrum antibiotics remains the cornerstone for the treatment of neonatal late onset sepsis (LOS). However, which antibiotics should be used is still debatable, as relevant studies were conducted more than 20 years ago, recruited in single centres or countries, evaluated antibiotics not in clinical use anymore and had variable inclusion/exclusion criteria and outcome measures. Moreover, antibiotic-resistant bacteria have become a major problem in many countries worldwide. We hypothesized that efficacy of meropenem as a broad-spectrum antibiotic is superior to standard of care regimens (SOC) in empiric treatment of LOS and aimed to compare meropenem to SOC in infants aged <90 days with LOS.

Methods and findings

NeoMero-1 was a randomized, open-label, phase III superiority trial conducted in 18 neonatal units in 6 countries. Infants with post-menstrual age (PMA) of ≤44 weeks with positive blood culture and one, or those with negative culture and at least with two predefined clinical and laboratory signs suggestive of LOS, or those with PMA >44 weeks meeting the Goldstein criteria of sepsis, were randomized in a 1:1 ratio to receive meropenem or one of the two SOC regimens (ampicillin+gentamicin or cefotaxime+gentamicin) chosen by each site prior to the start of the study for 8–14 days. The primary outcome was treatment success (survival, no modification of allocated therapy, resolution/improvement of clinical and laboratory markers, no need of additional antibiotics and presumed/confirmed eradication of pathogens) at test-of-cure visit (TOC) in full analysis set. Stool samples were tested at baseline and Day 28 for meropenem-resistant Gram-negative organisms (CRGNO). The primary analysis was performed in all randomised patients and in patients with culture confirmed LOS. Proportions of participants with successful outcome were compared by using a logistic regression model adjusted for the stratification factors. From September 3, 2012 to November 30th 2014, total of 136 patients (instead of planned 275) in each arm were randomized; 140 (52%) were culture positive. Successful outcome at TOC was achieved in 44/136 (32%) in the meropenem arm vs. 31/135 (23%) in the SOC arm (p = 0.087). The respective numbers in patients with positive cultures were 17/63 (27%) vs. 10/77 (13%) (p = 0.022). The main reason of failure was modification of allocated therapy. Treatment emergent adverse events occurred in 72% and serious adverse events in 17% of patients, the Day 28 mortality was 6%. Cumulative acquisition of CRGNO by Day 28 occurred in 4% of patients in the meropenem and 12% in the SOC arm (p = 0.052).

Conclusions

Within this study population, we found no evidence that meropenem was superior to SOC in terms of success at TOC, short term hearing disturbances, safety or mortality were similar in both treatment arms but the study was underpowered to detect the planned effect. Meropenem treatment did not select for colonization with CRGNOs. We suggest that meropenem as broad-spectrum antibiotic should be reserved for neonates who are more likely to have Gram-negative LOS, especially in NICUs where microorganisms producing extended spectrum- and AmpC type beta-lactamases are circulating.

Towards understanding global patterns of antimicrobial use and resistance in neonatal sepsis: insights from the NeoAMR network

OBJECTIVE

To gain an understanding of the variation in available resources and clinical practices between neonatal units (NNUs) in the low-income and middle-income country (LMIC) setting to inform the design of an observational study on the burden of unit-level antimicrobial resistance (AMR).

DESIGN

A web-based survey using a REDCap database was circulated to NNUs participating in the Neonatal AMR research network. The survey included questions about NNU funding structure, size, admission rates, access to supportive therapies, empirical antimicrobial guidelines and period prevalence of neonatal blood culture isolates and their resistance patterns.

SETTING

39 NNUs from 12 countries.

PATIENTS

Any neonate admitted to one of the participating NNUs.

INTERVENTIONS

This was an observational cohort study.

RESULTS

The number of live births per unit ranged from 513 to 27 700 over the 12-month study period, with the number of neonatal cots ranging from 12 to 110. The proportion of preterm admissions <32 weeks ranged from 0% to 19%, and the majority of units (26/39, 66%) use Essential Medicines List 'Access' antimicrobials as their first-line treatment in neonatal sepsis. Cephalosporin resistance rates in Gram-negative isolates ranged from 26% to 84%, and carbapenem resistance rates ranged from 0% to 81%. Glycopeptide resistance rates among Gram-positive isolates ranged from 0% to 45%.

CONCLUSION

AMR is already a significant issue in NNUs worldwide. The apparent burden of AMR in a given NNU in the LMIC setting can be influenced by a range of factors which will vary substantially between NNUs. These variations must be considered when designing interventions to improve neonatal mortality globally.

Thiamine Deficiency in a Child with Short Bowel Syndrome and Review

Thiamine (vitamin B₁) is a water-soluble vitamin that is not endogenously synthesized in humans. It is absorbed by the small intestine, where it is activated. Its active form acts as a coenzyme in many energy pathways. We report a rare case of thiamine deficiency in a 3.5-year old boy with short bowel syndrome secondary to extensive bowel resection due to necrotizing enterocolitis during his neonatal age. The patient was parenteral nutrition-dependent since birth and had suffered from recurrent central catheter-related bloodstream infections. He developed confusion with disorientation and unsteady gait as well as profound strabismus due to bilateral paresis of the abductor muscle. Based on these and a very low thiamine level he was diagnosed and treated for Wernicke encephalopathy due to incomplete thiamine acquisition despite adequate administration. He fully recovered after thiamine administration. After 1999 eight more cases have been reported in the PubMed mostly of iatrogenic origin.

Forecasting models of infections due to carbapenem-resistant Gram-negative bacteria in an intensive care unit in an endemic area

OBJECTIVES

The aim of this study was to forecast the monthly incidence rates of infections [infections/1000 bed-days (IBD)] due to carbapenem-resistant Klebsiella pneumoniae (CRKP), carbapenem-resistant Pseudomonas aeruginosa (CRPA), carbapenem-resistant Acinetobacter baumannii (CRAB) and total carbapenem-resistant Gram-negative bacteria (CRGNB) in an endemic intensive care unit (ICU) during the subsequent year (December 2016-December 2017) following the observational period.

METHODS

A 52-month observational period (August 2012-November 2016) was used. Two forecasting models, including a simple seasonal model for CRGNB, CRKP and CRPA and Winters' additive model for CRAB infections, were applied.

RESULTS

The models predicted the highest infection rates for CRKP, CRAB and CRGNB in January and September 2017 (23.8/23.4, 24.6/28.5 and 46.8/46.7 IBD, respectively) and for CRPA in February and March 2017 (8.3 and 7.9, respectively). The highest observed rates for CRKP, CRAB and CRGNB were indeed in January and September 2017 (25.6/19.0, 34.2/23.8 and 59.8/42.8 IBD, respectively); and for CRPA in February and March of the same year (15.2 and 12.7, respectively). The increased rates may be associated with personnel's annual work programme and behavioural factors.

CONCLUSION

Forecasting models in endemic ICUs may assist in implementation strategies for infection control measures.

Polyclonal predominance of concurrently producing OXA-23 and OXA-58 carbapenem-resistant Acinetobacter baumannii strains in a pediatric intensive care unit

We report a predominance (64.7%) of polyclonal carbapenem-resistant Acinetobacter baumannii (CRAB) strains concurrently producing OXA-23 and OXA-58 carbapenemases in a pediatric intensive care unit in an endemic area. This is the first report of emergence of such double-OXA CRAB strains in a single unit worldwide.

The clinical significance of carbapenem-resistant Klebsiella pneumoniae rectal colonization in critically ill patients: from colonization to bloodstream infection

PURPOSE

To highlight the clinical significance of carbapenem-resistant Klebsiella pneumoniae (CRKP) rectal colonization by examining the risk factors for CRKP rectal colonization and subsequent bloodstream infection (BSI) in critically ill patients.

METHODOLOGY

Prospective study of CRKP rectal colonization in an intensive care unit (ICU) during a 39-month period. CRKP strains isolated from both the blood cultures and corresponding rectal specimens (n=96) of patients were screened by PCR for the presence of antibiotic resistance-associated genes. Molecular analyses were conducted to investigate the clonal relatedness of CRKP strains from the rectal and blood specimens.

RESULTS

Among the 498 patients, 226 were rectally colonized by CRKP, 48 of whom developed a CRKP BSI. The median time from hospital admission to the detection of CRKP rectal colonization was 8 days, while the median time from colonization to BSI was 4 days. The duration of ICU stay, patient/nurse ratio and prior use of antianaerobic antimicrobials were associated with CRKP rectal colonization. No specific factor was associated with BSIs in the colonized patients. The blaKPC-2 gene was detected in all 96 strains, which were all classified as sequence type ST-258. Representative pairs (n=48) of CRKP strains colonizing and infecting the same patient shared the same pulsotype.

CONCLUSION

Our results indicate that hospitalized patients become infected with their colonizing strains, supporting the strong association between colonization and BSI. Limiting antianaerobic antimicrobial administration, reducing the duration of ICU stay and maintaining a low patient/nurse ratio are possible strategies to restrict rectal CRKP colonization in ICUs.

Colonization and Infection With Extensively Drug Resistant Gram-Negative Bacteria in Liver Transplant Recipients

BACKGROUND

Infections due to extensively drug resistant Gram-negative bacteria (GNB) after solid organ transplantation are increasing in prevalence and are associated with high morbidity and mortality. Surveillance culture (SC) seems to be an important tool for extensively drug resistant GNB control. The aim of this study was to evaluate colonization rates and subsequent infections by XDR-GNB in liver transplant recipients.

MATERIAL AND METHODS

This was a prospective cohort study in patients who underwent liver transplantation (LT) between January 2016 and January 2018. Data on demographics, extensively drug resistant colonization, and 3-month clinical outcomes were obtained. Colonization was defined as a positive surveillance culture (SC-perirectal) immediately before transplantation, once weekly after LT, and after intensive care unit discharge, with emphasis to carbapenem-resistant Gram-negative bacteria (CR-GNB).

RESULTS

Forty-four patients who underwent LT were included in the study. Ten patients (22.72%) were colonized with CR-GNB prior to transplantation, and 7/10 (70%) developed infection due to the same pathogen (5 patients bloodstream infections, 2 patients pneumonia) during the study period. Intensive care unit length of stay was significantly longer in colonized with CR-GNB patients (P < .05). Mortality rate was higher in colonized patients (30%) than in noncolonized (11.76%) (P = .2).

CONCLUSION

Our study results suggest an overall 70% risk of CR-GNB infection among colonized patients. Given the high mortality rate and the difficulty in treating these infections, further research to investigate and develop strategies to eliminate the colonization is needed.

Perioperative Chemoprophylaxis οr Treatment for Extensively Drug Resistant Gram-Negative Bacteria in Patients Undergoing Liver Transplantation Based on Preoperative Donor/Recipient Surveillance Cultures: A Prospective Study

INTRODUCTION

The importance of preoperative donor/recipient colonization or donor infection by extensively drug-resistant Gram-negative bacteria (XDR-GNB) and its relation to serious post-transplantation infection pathogenicity in liver transplantation (LT) patients has not been clarified.

AIM

Prevention of postoperative infection due to XDR-GNB with the appropriate perioperative chemoprophylaxis or treatment based on preoperative donor/recipient surveillance cultures in LT patients, as well as their outcome.

MATERIALS AND METHOD

Twenty-six patients (20 male, 6 female) were studied (average preoperative Model for End-Stage Liver Disease score ≈15, range: 8-29) from January 2017 to January 2018. In all patients, blood, urine, and bronchial secretions culture samples as well as a rectal colonization culture were taken pre- and postoperatively, once weekly after LT, and after intensive care unit discharge. Recipients with positive XDR-GNB colonization and patients receiving a transplant from a donor with an XDR-GNB positive culture or colonization received the appropriate chemoprophylaxis one half hour preoperatively according to culture results. De-escalation of the antibiotic regimen was done in 2 to 5 days based on the colonization/culture results of the donor and recipient and their clinical condition. Evaluation for serious infection was done at 1 week and at 28 days for outcome results.

RESULTS

Fourteen out of 26 recipients (53.8%) were positive for XDR-GNB colonization preoperative, with 2/14 (14.28%) presenting serious infection due to the same pathogen. Intensive care unit length of stay was significantly longer in colonized with XDR-GNB patients (P < .0001). The outcome of colonized patients was 6/14 (42.8%) expired, but only in 2/14 (14.2%) was mortality attributable to infection.

CONCLUSION

Administering appropriate perioperative chemoprophylaxis and treatment may limit the frequency of XDR-GNB infections and intensive care unit length of stay and may improve the outcome in LT recipients.

Development of case vignettes for assessment of the inter-rater variability of national validation teams for the point prevalence survey of healthcare-associated infections and antimicrobial use in European acute care hospitals

BACKGROUND

In 2016-17 the European Centre for Disease Prevention and Control (ECDC) organized the second point prevalence survey (PPS) of healthcare-associated infections (HCAIs) and antimicrobial use in European acute care hospitals. This survey included a validation study to maximize the accuracy of case identification and classification.

AIM

ECDC developed case vignettes to assess the performance of the national validation teams.

METHODS

Case vignettes were developed by two medical doctors with experience in the management of HCAIs and antimicrobial stewardship. The case vignettes were based on actual clinical cases. The distribution of HCAIs among the case vignettes reflected the distribution of HCAIs in the previous PPS. All case vignettes were pilot-tested by three expert raters. Agreement among the expert raters was measured using kappa statistics.

FINDINGS

Sixty case vignettes were developed. Twenty-nine of them were HCAI cases and 31 were cases without an HCAI. The inter-rater reliability using kappa statistics was 0.78 for the presence of HCAI and 0.89 for the antimicrobial use, respectively.

CONCLUSION

The agreement between the expert raters was very good for antimicrobial use and good for the presence of HCAI. Case vignettes can be a tool to support standardization of surveillance, improving the validity and comparability of the data.

Molecular Epidemiology of Endemic Carbapenem-Resistant Gram-Negative Bacteria in an Intensive Care Unit

The molecular epidemiology of endemic carbapenem-resistant Klebsiella pneumoniae (CRKP), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and carbapenem-resistant Acinetobacter baumannii (CRAB) in an intensive care unit located in an endemic area with high rates of resistance was investigated. A CRPA strain producing VIM and KPC concurrently was detected for the first time in an endemic area. CRKP strains producing K. pneumoniae carbapenemase predominated and were mainly assigned to the "hyperepidemic Greek clone." Predominant OXA-23-like producing CRAB strains were assigned to multiple pulsotypes.

2302. Bloodstream Infections Due to Carbapenem-Resistant Gram-Negative Bacteria in Pediatric Intensive Care Unit (PICU): Risk Factors and Outcomes

Background

Bloodstream infections (BSI) caused by multidrug-resistant bacteria are associated with poor outcome and increased cost. We investigated risk factors for carbapenem resistance (CR) and outcome associated with the development of BSI due to Gram-negative (GN) bacteria in PICU patients, a very vulnerable population.

Methods

We reviewed the records of 1 month–15 year old patients with documented GN BSI hospitalized in a PICU from 2005 to 2017. Isolates with meropenem MIC ≥16 mg/L were considered as resistant. Demographics, clinical characteristics, potential risk factors for acquisition of resistant strains, treatment, potential source control and outcome were recorded. Outcome was determined as microbiological response (negative blood cultures) within 5 days and mortality within 30 days. Both univariate and multivariable logistic regression analysis was performed and odds ratios (OR) with 95% confidence intervals (CI) were presented.

Results

81 patients with GN BSI were studied (34.6% Pseudomonas aeruginosa, 34.6% Acinetobacter baumannii and 30.9% Enterobacteriaceae), 21 with CR isolates. Risk factors for CR BSI were: prior carbapenem use (OR: 3.86, 95% CI: 1.10, 13.82) and renal replacement therapy (OR: 3.86, 95% CI: 1.10, 13.82). In multivariable outcome analysis, high levels of CRP (OR: 0.99, 95% CI: 0.99, 0.999), renal replacement therapy (OR: 0.11, 95% CI: 0.01, 0.71) and inotrope administration (OR: 0.30, 95% CI: 0.09, 0.91) were associated with poor microbiological response, whereas source control (OR: 2.99, 95% CI: 1.01, 9.43) with better microbiological response. High PRISM score III (OR: 1.15, 95% CI: 1.04, 1.29) and CR (OR: 5.07, 95% CI: 1.47, 19.36) were both independently associated with worse outcome, whereas source control was the only independent factor preventing death (OR: 0.24, 95% CI: 0.06, 0.78). In patients with CR BSI, administration of at least two active antimicrobials was associated with better outcome (OR: 10.80, 95% CI: 1.33, 237.05).

Conclusion

Prior carbapenem use is associated with carbapenem-resistant BSI development in PICU, which in turn is an independent risk factor for mortality. Source control is associated with better microbiological response within 5 days, as well as with decreased mortality.

Disclosures

All authors: No reported disclosures.

Advances in the Treatment of Mycoses in Pediatric Patients

The main indications for antifungal drug administration in pediatrics are reviewed as well as an update of the data of antifungal agents and antifungal policies performed. Specifically, antifungal therapy in three main areas is updated as follows: a) Prophylaxis of premature neonates against invasive candidiasis; b) management of candidemia and meningoencephalitis in neonates; and c) prophylaxis, empiric therapy, and targeted antifungal therapy in children with primary or secondary immunodeficiencies. Fluconazole remains the most frequent antifungal prophylactic agent given to high-risk neonates and children. However, the emergence of fluconazole resistance, particularly in non-albicans Candida species, should be considered during preventive or empiric therapy. In very-low birth-weight neonates, although fluconazole is used as antifungal prophylaxis in neonatal intensive care units (NICU's) with relatively high incidence of invasive candidiasis (IC), its role is under continuous debate. Amphotericin B, primarily in its liposomal formulation, remains the mainstay of therapy for treating neonatal and pediatric yeast and mold infections. Voriconazole is indicated for mold infections except for mucormycosis in children >2 years. Newer triazoles-such as posaconazole and isavuconazole-as well as echinocandins, are either licensed or under study for first-line or salvage therapy, whereas combination therapy is kept for refractory cases.

Ventilator-associated pneumonia in neonates and children: a systematic analysis of diagnostic methods and prevention

AIM

While ventilator-associated pneumonia (VAP) remains frequent in Pediatric ICU, there is no gold standard for diagnosis.

METHODOLOGY

We conducted a systematic PUBMED analysis (January 1990-January 2017) searching original, full-length studies addressing only pediatric patients; for VAP diagnosis, only those comparing different diagnostic methods and for VAP prevention those implementing preventive measures.

RESULTS

Among 367 articles, 17 and 16 were analyzed for diagnosis and prevention, respectively. For diagnosis, 13 studies used CDC criteria; whereas, 14 assessed algorithms: clinical pulmonary index score, ventilator-associated events and biomarkers. Among five randomized trials assessing preventive strategies one found a role of probiotics. Ventilator-care bundles reduced VAP rates.

CONCLUSION

Absence of diagnostic gold standard impedes comparison of current approaches and preventive strategies.

Impact of active surveillance and infection control measures on carbapenem-resistant Gram-negative bacterial colonization and infections in intensive care

BACKGROUND

Carbapenem-resistant Gram-negative bacteria (CRGNB) infections constitute a global threat for critically ill patients and the outcome of their hospitalization. Early identification of CRGNB through rectal surveillance cultures and routine infection control measures including contact precautions, use of appropriate disinfectants, staff education on cleaning, and hand hygiene may reduce the dissemination of CRGNB.

AIM

To assess the impact of enhanced infection control measures on CRGNB infections in a nine-bed polyvalent intensive care unit in a tertiary level hospital in an endemic area.

METHODS

A quasi-experimental study, which included patients with CRGNB infection retrospectively for six months and those participating in an active surveillance programme prospectively for the subsequent 22 months. Active surveillance programme (weekly rectal swabs) was implemented including two sub-periods with infection control measures and enhanced infection control measures. CRGNB incidence, prevalence, colonization pressure, infections and compliance with infection control measures and enhanced infection control measures were recorded. Analysis was performed through time-series and interrupted time-series.

FINDINGS

During the active surveillance programme, enhanced infection control measures led to a steeper downwards trend in incidence, prevalence, and colonization pressure for CRGNB compared to the infection control measures sub-period. The linear trend was for carbapenem-resistant Klebsiella pneumoniae (CRKP) and Pseudomonas aeruginosa (CRPA) infections to decrease from 19.6 to 8.1 infections per 1000 bed-days (IBD) (P = 0.001) and from 5.1 to 1.79 IBD (P = 0.043), respectively. By contrast, carbapenem-resistant Acinetobacter baumannii infections increased from 5.2 to 15.3 IBD (P = 0.001).

CONCLUSION

Enhanced infection control measures including enhanced hand hygiene, active surveillance combined with contact precautions, education, audits and feedback policies and interventions could reduce CRKP and CRPA in endemic areas.

Performance of QuantiFERON®-TB Gold In-Tube assay in children receiving disease modifying anti-rheumatic drugs

BACKGROUND

To evaluate the performance of the Quantiferon^®-TB Gold In-Tube (QFT-IT) interferon (IFN)-γ assay for the detection of latent tuberculosis infection (LTBI) in children receiving anti-rheumatic treatment in a tertiary referral hospital of Northern Greece.

METHODS

A total of 79 consecutive children receiving anti-rheumatic treatment [of which 18 screened prior to antitumor necrosis factor (TNF)-α treatment] were tested using Mantoux tuberculin skin test (TST) and QFT-IT. Association of both tests with risk factors for latent tuberculosis and Bacillus Calmette-Guerin immunization was determined. Influence of age, TNF-α inhibitors, systemic corticosteroids, conventional disease modifying anti-rheumatic drugs (DMARDs) and total duration of therapy on the QFT-IT mitogen-induced response was evaluated.

RESULTS

Agreement between TST and QFT-IT results was moderate (k=0.38). Frequency of QFT-IT indeterminate results was low (2.5%). In patients with risk factors for LTBI, the odds of a positive IFN-γ assay was increased by a factor of 27.6 (P=0.002), whereas there was no positive TST. There was a significant difference in the mitogen-induced IFN-γ secretion among various treatments (P=0.038). TNF-α inhibitors were associated with increased mitogen-induced IFN-γ secretion compared to monotherapy with conventional DMARDs (P=0.008). All children screened prior to anti-TNF-α treatment exhibited a negative QFT-IT and no active TB disease was detected during a 2-year follow-up.

CONCLUSIONS

QFT-IT may be a more reliable test than TST for detection of LTBI in children with rheumatic diseases receiving anti-rheumatic treatment. Drug regimen might influence the mitogen-induced IFN-γ secretion and the effect of TNF-α inhibitors might vary according to the specific agent administered.

Cluster-distinguishing genotypic and phenotypic diversity of carbapenem-resistant Gram-negative bacteria in solid-organ transplantation patients: a comparative study

Purpose. Solid-organ transplant recipients may display high rates of colonization and/or infection by multidrug-resistant bacteria. We analysed and compared the phenotypic and genotypic diversity of carbapenem-resistant (CR) strains of Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii isolated from patients in the Solid Organ Transplantation department of our hospital.Methodology. Between March 2012 and August 2013, 56 CR strains from various biological fluids underwent antimicrobial susceptibility testing with VITEK 2, molecular analysis by PCR amplification and genotypic analysis with pulsed-field gel electrophoresis (PFGE). They were clustered according to antimicrobial drug susceptibility and genotypic profiles. Diversity analyses were performed by calculating Simpson's diversity index and applying computed rarefaction curves.Results/Key findings. Among K. pneumoniae, KP-producers predominated (57.1 %). VIM and OXA-23 carbapenemases prevailed among P. aeruginosa and A. baumannii (89.4 and 88.9 %, respectively). KPC-producing K. pneumoniae and OXA-23 A. baumannii were assigned in single PFGE pulsotypes. VIM-producing P. aeruginosa generated multiple pulsotypes. CR K. pneumoniae strains displayed phenotypic diversity in tigecycline, colistin (CS), amikacin (AMK), gentamicin (GEN) and co-trimoxazole (SXT) (16 clusters); P. aeruginosa displayed phenotypic diversity in cefepime (FEP), ceftazidime, aztreonam, piperacillin, piperacillin-tazobactam, AMK, GEN and CS (9 clusters); and A. baumannii displayed phenotypic diversity in AMK, GEN, SXT, FEP, tobramycin and rifampicin (8 clusters). The Simpson diversity indices for the interpretative phenotype and PFGE analysis were 0.89 and 0.6, respectively, for K. pneumoniae strains (P<0.001); 0.77 and 0.6 for P. aeruginosa (P=0.22); and 0.86 and 0.19 for A. baumannii (P=0.004).Conclusion. The presence of different antimicrobial susceptibility profiles does not preclude the possibility that two CR K. pneumoniae or A. baumannii isolates are clonally related.

Use of Tigecycline in Pediatric Patients With Infections Predominantly Due to Extensively Drug-Resistant Gram-Negative Bacteria

BACKGROUND.

Emergence of extensively drug-resistant (XDR) bacteria has forced clinicians to use off-label antimicrobial agents such as tigecycline. We present our experience on salvage use of tigecycline for the treatment of infections caused by XDR Gram-negative bacteria in critically ill children and review published cases.

METHODS.

We conducted a retrospective chart review in pediatric departments of a tertiary level hospital from January 2009 to May 2014. Patients were identified using pharmacy database. For the literature review, relevant articles were identified from PubMed.

RESULTS.

In our case series, 13 children (7 males) with a median age of 8 years (range, 2.5 months-14 years) received tigecycline for ≥2 days as treatment for healthcare-associated infections including 5 bacteremias, 6 lower respiratory tract infections, and 3 other infections. Isolated pathogens were XDR Gram-negative bacteria except 1. A loading dose (range, 1.8-6.5 mg/kg) was given in all except 2 cases. Maintenance dose was given at 1-3.2 mg/kg q12 h. Other antimicrobials including colistin and aminoglycosides (85% and 62%, respectively) were coadministered to all patients. No serious adverse events were detected in these very ill children. Twenty cases of children treated with tigecycline were previously published, mostly for multidrug-resistant/XDR bacteria. An episode of acute pancreatitis and neutrophil engraftment delay in 2 cases were reported during tigecycline treatment. Analyzing reported and all our cases together, mortality in bloodstream infections was 86%, whereas in nonbacteremic cases it was 24% (P = .009).

CONCLUSIONS.

Tigecycline, given at the range of administered doses as salvage therapy and in combination with other antimicrobial agents, seemed to be well tolerated in a series of mainly critically ill pediatric patients and demonstrated relatively good clinical response in nonbacteremic patients.

Comparison of cotrimoxazole vs. second-generation cephalosporins for prevention of urinary tract infections in children

BACKGROUND

Antimicrobial prophylaxis is recommended for the prevention of urinary tract infections (UTI) in high-risk children. However, there is growing concern about the use of β-lactams as prophylaxis and subsequent development of antibiotic resistance.

METHODS

In this prospective, randomized, crossover controlled trial we compared cotrimoxazole (SXT) and second-generation cephalosporins (2GC) as UTI prophylaxis in children ranging in age from 1 to 60 months. Eligible patients were 1:1 randomized to receive either SXT or 2GC for the initial 6-month period (1 course), then switched to the other antimicrobial agent class for the subsequent course, with switching continuing after each course until the end of the study. Urethral orifice cultures (UOCs) were obtained at the time of switching antimicrobial prophylaxis.

RESULTS

Among 97 children (mean age 13.6 months) on prophylaxis, breakthrough UTIs occurred during 13.3 % (10/75) of SXT courses and 10.3 % (8/78) of 2GC courses (p = 0.62). 2GC failed earlier than SXT (mean ± standard error: 0.81 ± 0.1 vs. 2.37 ± 0.36 months, respectively; p = 0.028). Pseudomonas aeruginosa and Enterococcus spp. were more frequently isolated after 2GC courses than after SXT courses [22.6 vs. 4.8 % (p = 0.02) and 20.7 vs. 4.8 % (p = 0.035), respectively]. Prophylaxis with 2GC significantly increased resistance to both 2GC and SXT, while SXT prophylaxis did not affect susceptibility to 2GC.

CONCLUSIONS

While SXT and 2GC appear to be equally efficacious as UTI prophylaxis in children, the latter exert a broader effect on patients' flora and development of bacterial resistance, suggesting that SXT may be more appropriate for UTI prophylaxis than 2GC.

Nosocomial bloodstream infections in neurosurgery: a 10-year analysis in a center with high antimicrobial drug-resistance prevalence

BACKGROUND

Data on nosocomial bloodstream infections (NBSI) in neurosurgery is limited. This study aimed to analyze the epidemiology, microbiology, outcome, and risk factors for death in neurosurgical patients with NBSI in a multidrug resistant setting.

METHODS

Neurosurgical patients with a confirmed NBSI within the period 2003-2012 were retrospectively analyzed. NBSI was diagnosed when a pathogen was isolated from a blood sample obtained after the first 48 h of hospitalization. Patients' demographic, clinical, and microbiological data were recorded and analyzed using univariate and multivariate analysis.

RESULTS

A total of 236 patients with NBSI were identified and 378 isolates were recovered from blood cultures. Incidence of NBSI was 4.3 infections/1000 bed-days. Gram-negative bacteria slightly predominated (54.5 %). The commonest bacteria were coagulase-negative staphylococci (CoNS, 26 %), Klebsiella pneumoniae (15.3 %), Pseudomonas aeruginosa (14.8 %), and Acinetobacter baumannii (13.2 %). Carbapenem resistance was found in 90 % of A. baumannii, in 66 % of P. aeruginosa, and in 22 % (2003-2007) to 77 % (2008-2012) of K. pneumoniae isolates (p < 0.05). Most CoNS and Staphylococcus aureus isolates (94 and 80 %, respectively) were methicillin-resistant. All Gram-negative isolates were sensitive to colistin and all Gram-positive isolates were sensitive to vancomycin and linezolid. Antimicrobial consumption decreased after 2007 (p < 0.05). Overall mortality was 50.4 %. In multivariate analysis, advanced age and stay in an Intermediate Care Unit (IMCU) were independent risk factors for in-hospital mortality (p < 0.05).

CONCLUSIONS

Overall, high incidence of NBSI and considerable resistance of Gram-positive and particularly Gram-negative bacteria were noted in neurosurgical patients. Mortality was high with advanced age and stay in IMCU being the most important death-related factors.

Molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae in Greece

Hospital infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) constitute a worldwide problem associated with high rates of treatment failure and mortality. In Greece, CRKP have emerged in 2002 due to VIM carbapenemase production and later due to KPC, NDM and OXA-48-like carbapenemases that have become endemic. The molecular epidemiology of CRKP strains is dynamic, as antibiotic consumption and worldwide traveling are strongly associated with global spread of CRKP isolates. Lately, porin defects, such as disruption of OmpK35 and production of OmpK36 variant, have also contributed to carbapenem resistance. In the coming years, the high prevalence of CRKP will require intense infection control measures, while novel molecular patterns may appear. To our knowledge, this is the first review analyzing the molecular epidemiology of CRKP strains in Greece.

Tigecycline for treatment of carbapenem-resistant Klebsiella pneumoniae infections after liver transplantation in the intensive care unit: a 3-year study

BACKGROUND

This 3-year prospective, observational, single-center study was undertaken to describe prescription, microbiology findings, tolerance, and efficacy of tigecycline for carbapenem-resistant Klebsiella pneumoniae (CRKP) infections after liver transplantation in the intensive care unit (ICU).

METHODS

All patients after liver transplantation treated with tigecycline for ≥3 days for CRKP infections in our ICU from January 1, 2010, to December 31, 2012, were studied. Patient characteristics, indication of treatment, bacteriology, and ICU mortality were collected. The main end points were clinical and microbiologic efficacy and tolerance of tigecycline.

RESULTS

Over the study period, 8 men and 2 women (18 CRKP isolates), aged 54.3 ± 7.7 years, were included in the study. Acute Physiology and Chronic Health Evaluation and Sequential Organ Failure Assessment scores on ICU admission were 13.7 ± 2.7 and 10 ± 2.2, respectively. In 7 isolates, tigecycline was prescribed for CRKP blood stream infection (BSI), in 6 for complicated intra-abdominal infection (IAI), in 2 for ventilator-associated pneumonia (VAP), in 2 for surgical site infection, and in 1 for urinary tract infection. In 4 cases, tigecycline was prescribed for secondary BSI followed by VAP and/or IAI. All isolates were susceptible to tigecycline, 83.4% to colistin, 44.5% to gentamicin, and 27.8% to amikacin. In 2 patients, tigecycline was prescribed as monotherapy. Three patients had clinical failure. The microbiologic response rate was 70%. Superinfection was detected in 5 patients, and Pseudomonas aeruginosa was the most frequently isolated pathogen. Tigecycline was generally well tolerated. The ICU mortality rate was 60% with attributable mortality rate 30%.

CONCLUSIONS

Our pilot study suggests that tigecycline shows a good safety and tolerance profile in patients with CRKP infections in the ICU after orthotopic liver transplantation. Limited therapeutic options for such infections leave physicians no choice but to use tigecycline for off-label indications such as urinary tract and blood stream infections.

Diagnosing ventilator-associated pneumonia in pediatric intensive care

The Centers for Disease Control and Prevention's criteria were applied by independent investigators for ventilator-associated pneumonia (VAP) diagnosis in critically ill children and compared with tracheal aspirate cultures (TACs). In addition, correlation between antibiotic use, VAP incidence, and epidemiology of TACs was investigated. A modest agreement (κ = 0.41) was found on radiologic findings between 2 investigators. VAP incidence was 7.7 episodes per 1,000 ventilator days, but positive TACs were the most significant factor for driving high antimicrobial usage in the pediatric intensive care unit.

A 5-Year Epidemiological Study of Nosocomial Bloodstream Infections in a Neurosurgery Department

The characteristics of nosocomial bloodstream infections (BSIs) in a neurosurgical department were studied over a 5-year period. The rate of nosocomial BSI was 3.0%. Gram-negative bacteria were the most commonly isolated pathogens (65.9% of isolates). For all the pathogens isolated, the rate of resistance to commonly used antimicrobial agents was high. Of the 101 patients with nosocomial BSI, 50 (49.5%) died during their stay at the Department of Neurosurgery. At the same time, overall mortality rate among neurosurgical inpatients without nosocomial BSI was 5.4% (ie, 175 of 3,216 patients died).