The Increasing Challenge of Multidrug-Resistant Gram-Negative Bacilli: Results of a 5-Year Active Surveillance Program in a Neonatal Intensive Care Unit

Surveillance of Multidrug-Resistant Pathogens in Neonatal Intensive Care Units of Palermo, Italy, during SARS-CoV-2 Pandemic

BACKGROUND

Antimicrobial resistance (AMR) is a topic of concern, especially in high-level care departments like neonatal intensive care units (NICUs). The systematic use of an "active" epidemiological surveillance system allows us to observe and analyze any changes in microbial distribution, limiting the risk of healthcare-associated infection (HAI) development.

METHODS

We have conducted a longitudinal observational study in the five NICUs of Palermo, comparing the "pre-pandemic period" (March 2014-February 2020) with the "pandemic" one (March 2020-February 2022). The primary aim of the study was to evaluate the cumulative prevalence of carriage from multi-drug resistant (MDR) bacteria in the cumulative NICUs (NICU C).

RESULTS

During the "pre-pandemic period", 9407 swabs were collected (4707 rectal, 4700 nasal); on the contrary, during the "pandemic period", a total of 2687 swabs were collected (1345 rectal, 1342 nasal). A statistically significant decrease in MDR-Gram-negative bacteria (GNB) carriage prevalence was detected during the pandemic. At the same time, there was a general worsening of the carriage of carbapenemase-forming MDR-GNB (CARBA-R+) and methicillin-resistant Staphylococcus aureus (MRSA) during the pandemic period. A significant reduction in methicillin-susceptible Staphylococcus aureus (MSSA) carriage was detected too.

CONCLUSIONS

The surveillance of MDRO carriage in NICUs is fundamental for limiting the social and economic burden of HAIs.

Incidence of infant Gram-negative invasive bacterial infections in England, 2011-2019: an observational study using population-wide surveillance data

OBJECTIVE

Invasive bacterial infections account for an estimated 15% of infant deaths worldwide. We aimed to estimate the incidence and trends in invasive bacterial infections in infants caused by Gram-negative pathogens in England during 2011-2019.

METHODS

Laboratory-confirmed invasive bacterial infections in infants (<1 year old) were identified in the UK Health Security Agency national laboratory surveillance data from April 2011 to March 2019. Polymicrobial infections were defined as two or more bacterial species from the same normally sterile sample site. Early-onset infections were defined as <7 days from birth and late-onset as ≥7 days (neonates 7-28 days; infants ≥29 days). Trend analyses were carried out using Poisson (for episodes/incidence) and beta (for proportions) regression.

RESULTS

The annual incidence of invasive bacterial infections increased by 35.9%, from 189.8 to 258.0 cases per 100 000 live births (p<0.001). Late-onset infections in both neonates and infants increased substantially over the study period (p<0.001), whereas early-onset infections increased slightly (p=0.002). Escherichia coli was the most common Gram-negative pathogen isolated and accounted for 27.2% of the overall rise in Gram-negative infant disease incidence. Polymicrobial infections almost doubled, increasing from 29.2 to 57.7 per 100 000 live births (p<0.001), and mostly involved two species (81.3%, 1604/1974 episodes).

CONCLUSIONS

The incidence of Gram-negative invasive bacterial infections in infants increased between 2011/2012 and 2018/2019 in England, driven mainly by an increase in late-onset infections. Further work is required to elucidate the risk factors and drivers of this increased incidence so that opportunities for prevention can be identified.

Intestinal Colonization of Preterm Neonates with Carbapenem Resistant Enterobacteria at Hospital Discharge

Our aim was to investigate gut colonization with carbapenem-resistant Enterobacterales (CRE) in the population of preterm neonates at discharge from a tertiary care center in Serbia. The study included 350 randomly selected neonates/infants discharged in the period April 2018-May 2019. CRE colonization was present in 88/350 (25.1%) of patients. Klebsiella pneumoniae producing KPC and OXA-48 carbapenemase were detected in 45 and 42 subjects, respectively, while NDM producing Escherichia coli was identified in one patient only. All OXA-48 strains harbored bla_CTX-M-15, while both bla_TEM and bla_SHV were present in all but one KPC-producing strain. CRE isolates exhibited a multidrug resistance pattern with uniform fluoroquinolone resistance, universal susceptibility to colistin, and variable susceptibility to aminoglycosides. Administration of carbapenems was common (~50%) and it was strongly associated with colonization, as well as the combinational therapeutic regimens that included meropenem, contrary to ampicillin-sulbactam/colistin therapy and prolonged course of the initial therapy (ampicillin/amikacin ≥ 7 days). Other risk factors for CRE carriage were level of immaturity, admission to neonatal intensive care unit, prolonged hospitalization and invasive procedures. Although the rate of clinically and/or laboratory proven systemic infections was significantly higher among colonized patients, CRE infection was confirmed in one patient only (1.1%) that was colonized with NDM E. coli. Clonal relatedness of CRE isolates was high, with seven and eight clusters detected among KPC (N = 30) and OXA-48 (N = 37) producing strains, respectively. The follow up of the 31 KPC-colonized patients after discharge from hospital revealed common decolonization within one month (~68%). In conclusion, our results demonstrated a high rate of CRE colonization that is most likely related to carbapenem consumption and lack of screening as important infection prevention practice.

Effects of Perinatal Antibiotic Exposure and Neonatal Gut Microbiota

Antibiotic therapy is one of the most important strategies to treat bacterial infections. The overuse of antibiotics, especially in the perinatal period, is associated with long-lasting negative consequences such as the spread of antibiotic resistance and alterations in the composition and function of the gut microbiota, both of which negatively affect human health. In this review, we summarize recent evidence about the influence of antibiotic treatment on the neonatal gut microbiota and the subsequent negative effects on the health of the infant. We also analyze the possible microbiome-based approaches for the re-establishment of healthy microbiota in neonates.

Cumulative Antibiogram: A Rapid Method to Hinder Transmission of Resistant Bacteria to Oral Cavity of Newborn Babies

BACKGROUND

A rapid bacterial diagnostic is needed more and more in the treatment of patients, because of the emergence of antibiotic resistance. The cumulative antibiogram, an annual report that monitors antimicrobial resistance trends in health care facilities, may provide a profile of empirical therapy useful in diverse emergency situations, such as transmission of resistant bacteria to oral cavity of newborn babies. We aimed to draw a profile of antibiotic resistance encountered.

METHODS

We assessed the antibiotic resistance (ABR) profile in childbearing women and newborn babies in Ploiesti Obstetrics and Gynecology Hospital by the disk diffusion method characterizing the multidrug-resistant organisms after isolation and identification by phenotypic tests. Extended-spectrum β-lactamase (ESBL)-producing Enterobacterales (ESBL-E), Carbapenem-resistant Enterobacterales (CRE), vancomycin-resistant Enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin resistant Group B Streptococcus (VR-GBS) were detected.

RESULTS

The prevalence of antibiotic resistance was 11.32% (53/468), while the prevalence of the ESBL-E, MRSA, VRE and VR-GBS strains was 8.34% (39/468). Within the bacteria isolated from fifty-three childbearing women, the prevalence of ESBL-E, MRSA, VRE and VR-GBS was 22.64% (12/53), 32.08% (17/53), 11.32% (6/53) and 7.55% (4/53). In the whole studied group, the prevalence was 2.56% (12/468), 3.63% (17/468), 1.28% (6/468) and 0.86% (4/468). Resistant bacteria were detected at birth in the oral cavity of the newborn babies in all cases. Maternal and neonatal isolates shared similar characteristics.

CONCLUSIONS

Cumulative antibiogram is useful in case of empiric treatment needed in diverse emergencies, such as transmission of resistant bacteria to oral cavity of newborn babies.

Intravenous Fosfomycin: A Potential Good Partner for Cefiderocol. Clinical Experience and Considerations

Multidrug resistant Gram-negative bacteremia represents a therapeutic challenge clinicians have to deal with. This concern becomes more difficult when causing germs are represented by carbapenem resistant Acinetobacter baumannii or difficult-to-treat Pseudomonas aeruginosa. Few antibiotics are available against these cumbersome bacteria, although literature data are not conclusive, especially for Acinetobacter. Cefiderocol could represent a valid antibiotic choice, being a molecule with an innovative mechanism of action capable of overcoming common resistance pathways, whereas intravenous fosfomycin may be an appropriate partner either enhancing cefiderocol activity or avoiding resistance development. Here we report two patients with MDR Gram negative bacteremia who were successfully treated with a cefiderocol/fosfomycin combination.

Admission Outcome and Antimicrobial Resistance Pattern of Bacterial Isolates among Neonates with Suspected Sepsis in Neonatal Intensive Care Unit at Dessie Comprehensive Specialized Hospital, Dessie, Northeastern Ethiopia

Background

Neonatal sepsis is a major cause of morbidity and mortality globally. The aim of this study was to assess admission outcome and antimicrobial susceptibility pattern of bacterial isolates among neonates with suspected sepsis at the Dessie Comprehensive specialized Hospital (DCSH), Northeastern Ethiopia.

Method

Cross-sectional study was conducted from August 2017 to March 2018. Two hundred forty-six neonates were recruited, and each patient's blood specimen was collected aseptically using bottle containing Brain Heart Infusion for blood culture. Both clinical and laboratory data such as bacterial culture growth and antimicrobial susceptibility pattern were collected from the neonate; clinical data from the mothers were also included. Antimicrobial susceptibility testing was performed using Kirby-Bauer disk diffusion method. The data were analyzed using SPSS version 20.

Results

Bacteria were identified from 67 (27.2%) blood cultures. The predominant pathogen was Escherichia coli (35.8%) followed by Staphylococcus aureus (26.8%), and Coagulase Negative Staphylococcus (CoNS) (19.4%). The isolated bacteria showed resistance to Ampicillin 55 (82%), third-generation Cephalosporins 21 (58.3%) and other tested antimicrobials. Overall, 68.6% bacterial isolates demonstrated Multidrug resistance (MDR) and total registered mortality rate was 12/246 (4.8%). Both neonatal factors such as neonatal temperature, septic umbilicus and utilization of indwelling medical device during delivery; and maternal factors such as age, antenatal urinary tract infection (UTI), mode of delivery and prolonged rupture of membrane (PROM) had shown statistically significant association with bacterial sepsis.

Conclusion

The rate of bacterial growth was found to be high; E. coli and S. aureus were the predominant organisms. Both maternal and neonatal related data were strong predictors for bacterial infection of the neonate. Therefore, improving infrastructures for screening of bacteremia as well as active surveillance in clinical setting needed to ensure proper empirical therapy.

Knowledge, Attitudes, and Practices of NICU Doctors and Nurses Toward Prevention and Control of Nosocomial Infection With Multidrug Resistant Organism

BACKGROUND

Nosocomial infection with multidrug resistant organisms (MDRO) can directly influence the curative effect and the prognosis of neonates, bringing great difficulties to clinical treatment. As direct contacts of neonates, the knowledge, attitudes, and practices (KAP) of doctors and nurses are critical for the prevention and control of MDRO infection in neonatal intensive care units (NICUs).

PURPOSE

This study describes the KAP of doctors and nurses in NICUs toward the prevention and control of nosocomial infection with MDRO and analyzes its influencing factors.

METHODS

This cross-sectional study used convenience sampling to survey 397 doctors and nurses from the NICU of 28 hospitals in 11 cities in Zhejiang Province, China. A univariate analysis and a multiple linear regression were used to analyze the data.

RESULTS

The median scoring rate (interquartile range) of the knowledge, attitude, and practice questionnaire was 0.86 (0.82-0.91), 0.98 (0.91-1.00), and 0.995 (0.97-1.00), respectively. However, the median scoring rate regarding "basic knowledge of MDRO" and "special prevention and control measures" was 0.50 in knowledge. The multiple linear regression showed that the influencing factors of KAP were hospital grade, professional title, gender, regular supervision, and training.

CONCLUSIONS

There was still room for improvement in the KAP of NICU doctors and nurses, especially regarding the knowledge. Men, doctors and nurses in Grade II hospitals, and doctors and nurses with primary professional titles had worse KAP. Training and supervision helped improve the KAP.

RELEVANCE TO CLINICAL PRACTICE

To improve the KAP of doctors and nurses to enhance the prevention and control effect for the MDRO infection in NICUs, hospitals and departments should carry out targeted training and strengthen supervision, while Grade II hospitals, men, and doctors and nurses with primary professional titles need more attention.

Impact of a multi-strain probiotic administration on peri-rectal colonization with drug-resistant Gram-negative bacteria in preterm neonates

BACKGROUND

Infections caused by drug resistant Gram-negative bacteria (DR-GNB) are a major health concern for hospitalized preterm neonates, globally. The aim of this study was to investigate the effect of a multi-strain probiotic on the incidence of rectal colonization with DR-GNB in preterm neonates.

METHODS

A double-blind, placebo-controlled, randomized clinical trial was conducted including 200 neonates, randomly allocated to a multi-strain probiotic (n = 100) or placebo (n = 100).

RESULTS

Fifteen percent of the neonates showed peri-rectal colonization with DR-GNB on the day of enrolment indicating probable maternal-to-neonate (vertical) bacterial transmission or environmental acquisition at time of delivery, with no difference between groups. Acquisition of further DR-GNB colonization was rapid, with an increase from 15% on the day enrolment to 77% by day 7 and 83% by day 14 of life. By day 7 (corresponding to early gut colonization), neonates in the probiotic group were 57% less likely to have peri-rectal DR-GNB colonization [OR: 0.43 (0.20-0.95); p = 0.04] and by day 14 (corresponding to late gut colonization), neonates in the probiotic group were 93% less likely to have peri-rectal DR-GNB colonization [OR: 0.07 (0.02-0.23); p < 0.001].

CONCLUSION

Hospitalized neonates showed substantial peri-rectal colonization with DR-GNB at enrolment and further rapid acquisition of DR-GNB in the first 2 weeks of life. The use of a multi-strain probiotic was effective in reducing early and late neonatal gut colonization with DR-GNB.

CLINICAL TRIAL REGISTRATION

The trial was registered at the Pan African Clinical Trial Registry (PACTR202011513390736).

Neonatal multidrug-resistant gram-negative infection: epidemiology, mechanisms of resistance, and management

Infants admitted to the neonatal intensive care unit, particularly those born preterm, are at high risk for infection due to the combination of an immature immune system, prolonged hospitalization, and frequent use of invasive devices. Emerging evidence suggests that multidrug-resistant gram-negative (MDR-GN) infections are increasing in neonatal settings, which directly threatens recent and ongoing advances in contemporary neonatal care. A rising prevalence of antibiotic resistance among common neonatal pathogens compounds the challenge of optimal management of suspected and confirmed neonatal infection. We review the epidemiology of MDR-GN infections in neonates in the United States and internationally, with a focus on extended-spectrum β-lactamase (ESBL)-producing Enterobacterales and carbapenem-resistant Enterobacterales (CRE). We include published single-center studies, neonatal collaborative reports, and national surveillance data. Risk factors for and mechanisms of resistance are discussed. In addition, we discuss current recommendations for empiric antibiotic therapy for suspected infections, as well as definitive treatment options for key MDR organisms. Finally, we review best practices for prevention and identify current knowledge gaps and areas for future research. IMPACT: Surveillance and prevention of MDR-GN infections is a pediatric research priority. A rising prevalence of MDR-GN neonatal infections, specifically ESBL-producing Enterobacterales and CRE, compounds the challenge of optimal management of suspected and confirmed neonatal infection. Future studies are needed to understand the impacts of MDR-GN infection on neonatal morbidity and mortality, and studies of current and novel antibiotic therapies should include a focus on the pharmacokinetics of such agents among neonates.

Colonization with Multidrug-Resistant Bacteria in the First Week of Life among Hospitalized Preterm Neonates in Serbia: Risk Factors and Outcomes

The aim of this prospective cohort study was to determine the prevalence of gut colonization with multidrug-resistant (MDR) bacteria, risk factors for colonization, infection risk, and outcomes among preterm neonates hospitalized at a tertiary-care center in Serbia. During the period from December 2017 to April 2018, 103 neonates were screened for rectal carriage at admission and on the seventh day of life. Characterization of MDR strains was done by conventional microbiology and molecular methods. Out of 61 (59.2%) colonized neonates, 12 (11.6%) were found colonized at admission, while 49 (47.6%) became colonized at the study site. Among a total of 72 MDR isolates, extended-spectrum beta-lactamase (ESBL)-producing enterobacteria prevailed (56/72, 77%), followed by Acinetobacter baumannii (14/72, 19%). The majority of ESBL-producing strains carried multiple genes (blaTEM/blaCTX-M-15 or blaTEM/blaSHV). Longer previous hospitalization and delivery by cesarean section were associated with MDR colonization, while mechanical ventilation was a risk factor for colonization at the study site. Infections due to MDR bacteria were more frequent among colonized than non-colonized neonates, but not significantly, and mortality was low (1%) in the studied neonates. These results indicate that hospitalized preterm neonates in Serbia are rapidly colonized with a diversity of MDR species and resistance phenotypes/genotypes.

Incidence of emerging multidrug-resistant organisms and its impact on the outcome in the pediatric intensive care

Background

Healthcare-associated infections (HCAI) are a worldwide threat in intensive care units particularly in the pediatric intensive care units with a major cause of morbidity and mortality among this age group. The aim of the study is to determine the prevalence and risk factors predisposing to multidrug-resistant organisms (MDROs) infections among pediatric intensive care unit (PICU) patients at Ain Shams Pediatric University Hospitals as well as determining mortality and morbidity rates along with the length of stay at PICU.

Results

Culture results revealed that of the 282 patients evaluated, only 26 (9.2%) were MDROs (half of the affected patients had Acinetobacter species (50%) and the rest of them were free, 256 (90.8%). Our study revealed that the majority of MDROs were isolated from sputum in more than half of the patients 19/32 (59.3%) followed by whole blood in 10/32 (31.2%) and urine in 3/32 (9.4%). Pulmonary system was the most common affected site and was mainly colonized by MDR Acinetobacter (71.4%) followed by MDR Klebsiella (41.6%). Regarding MDR risk factors in our PICU, multivariate logistic regression analyses showed significant relationship between MDROs and age under 1 year (odds ratio [OR] 2.4554; 95% confidence interval [95% CI] (1.072–5.625); p = 0.043) and underlying pulmonary disease (OR 2.417; 95% CI (1.014–5.761); p = 0.592). A statistically significant higher mortality was detected in patients colonized with MDROs 9/26 (34.6%) versus MDROs non-colonized patients 32/256 (12.5%) [P=0.002]. Moreover, MDROs infection has negative significant risk with discharged patients ([OR] 0.269; [95% CI] (0.111–0.656); p = 0.002). Additionally, patients infected with MDROs did have significantly greater PICU stay than those non-infected [median (IQR), 16.5 (10.7–22), 5 (4–8), P=0.00] and have longer ventilation [median (IQR), 15.5 (10–18), 3 (2–10), P=0.00].

Conclusion

Prevalence of MDROs (9.2%) was low among PICU cases at Ain Shams University Hospitals. Most common MDROs were Acinetobacter and Klebsiella followed by pseudomonas species. The frequency of gram-negative organisms is much more common than gram-positive organisms. An increasing rate of antimicrobial resistance with increasing mortality and morbidity among PICU patients is observed worldwide; even for new categories, so, strict infection control programs should be implemented.

Investigation of Extended-Spectrum β-Lactamase and Carbapenemase Producing Gram-Negative Bacilli in Rectal Swabs Collected from Neonates and Their Associated Factors in Neonatal Intensive Care Units of Southern Ethiopia

Background

Currently extended-spectrum β-lactamase (ESβL) and carbapenemase producing gram-negative bacteria are the greatest concern among the neonatal population with very limited therapeutic options. The aim of this study was to assess the prevalence of ESβL and carbapenemase producing gram-negative bacilli, associated factors and antimicrobial resistance patterns among neonates in intensive care units.

Methods

An institutional-based cross-sectional study was conducted from February to June 2021 on 212 neonates in intensive care units. Risk factors data were collected by using a well-designed questionnaire. A rectal swab sample was collected using a sterile cotton swab and inoculated on MacConkey agar. Bacterial isolates were identified using various biochemical tests. ESβL and carbapenemase were first screened by indicator cephalosporins (cefotaxime (30µg) and ceftazidine (30µg)) and carbapenem (meropenem and ertapenem), respectively. ESβL and carbapenemase were confirmed by a double-disk synergy test and modified carbapenem inactivation methods, respectively. SPSS version 21.0 was used for data analysis. A P-value ≤ 0.05 was considered as statistically significant.

Results

The overall prevalence of ESβL-producing gram-negative bacilli was 72/212 (34%). The predominant ESβL-producing isolate was Klebsiella pneumoniae 23/72 (31.9%) followed by Escherichia coli 17/72 (23.6%). Five (2.4%) carbapenemase-producing gram-negative bacilli were isolated. ESβL-producing isolates showed a high resistance against ampicillin 72/72 (100%), augmentin 69/72 (95.8%) and gentamycin 57/72 (79.2%). The majority 63/72 (87.5%) of isolated ESβL-producing gram-negative bacilli were multi-drug resistant (MDR). Rectal carriage of ESβL by neonates showed a statistically significant association with endotracheal intubation (p = 0.001; AOR = 4.2; 96% CI = (1.8–9.5)), treatment with ampicillin+gentamycin (p = 0.004; AOR = 3.3; 95% CI = (1.5–7.6)) and staying in a neonatal intensive care unit (NICU) between 11 and 20 days (p = 0.042; AOR = 2; 95% CI = (1.0–4.5)).

Conclusion

A high prevalence of ESβL-producing bacterial isolates was observed for commonly used antibiotics which needs further attention. Therefore, continuous and regular follow-ups of drug resistance patterns is important for the proper treatment and management of ESβL and carbapenemase producing gram-negative bacilli.

A High Distribution of Resistant Pathogens among Critically Ill Neonates from Secondary Referral Hospital of Indonesia

Background

The spread of resistant pathogens among critically ill neonates has increased in recent years. Therefore, information about the antimicrobial profile and its susceptibility over time helps to select the most appropriate therapy. The study assesses the distribution of resistant pathogens and its susceptibility among neonates' patients.

Methods

Eight hundred and eight suspected neonatal infected from January 2011 to December 2019 were recruited anonymously in our retrospective, observational analysis. The study was conducted in the secondary-care level NICU which located on the western border of Jakarta, Indonesia. The MDROs definition was define by Centre for Disease Prevention and Control (CDC) criteria and standardized international terminology. Microbial identification and susceptibility testing were carried out following standard protocols.

Results

Culture positivity was found in 132 (16.3%) with dominating MDR-Gram negative bacteria 47 (61.8%). The most common pathogens were extended-spectrum β-lactamase and multidrug-resistant Acinetobacter 18 (38.3%), respectively. There were coagulase negative staphylococci 29 (38.2%) among MDROs. Most of the Gram negative bacteria were highly susceptible to the combination of cefoperazone/sulbactam (79.6%), amikacin (88.7%), and tigecycline (77.1%). Staphylococcus aureus had a good susceptibility to almost all classes' antibiotics. Candida isolates showed 100.0% susceptibility to all antifungal classes.

Conclusions

Our study highlighted the microbial profile along with its susceptibility among neonatal patients that able to provide necessary information for antimicrobial guidelines and policies for effective infectious case management.

Mother-to-Neonate Transmission of Antibiotic-Resistant Bacteria: A Cross-Sectional Study

We evaluated carriage rates of extended spectrum β-lactam-producing Enterobacterales (ESBL-E), Carbapeneme-resistant Enterobacterales (CRE), vancomycin-resistant Enterococci (VRE), and methicillin-resistant Staphylococcus aureus (MRSA) among pregnant women and determined the maternal-to-neonate transmission rates of these antibiotic-resistant bacteria (ARB). Pregnant women provided rectal and vaginal samples, proximal to delivery. Stool samples were collected from newborns within 48 h of birth. All samples were cultured on selective media for ARB identification. Clinical and demographic data were collected from the participants' medical files. We performed molecular and phenotypic characterization of the different resistance mechanisms, and determined the isolates' antibiotic susceptibility and biofilm-forming ability. The prevalence of ESBL-E, MRSA and VRE among pregnant women were 16%, 6% and 1%, respectively. The prevalence of ESBL-E and MRSA among neonates were 7.6% and 1.6%, respectively. Maternal-to-neonate transmission rates of ESBL-E and MRSA were 48% and 27.8%, respectively. Maternal and neonatal isolates shared similar characteristics. Maternal-to-neonate transmission of ARB plays an important role in bacterial colonization in newborns. Future studies should investigate the outcomes of the high ESBL-E transmission rate. The biofilm-forming ability of ARB was found to affect transmission. Additional factors should be investigated in order to understand the differences between transmitted and non-transmitted bacteria.

Clonal relatedness in the acquisition of intestinal carriage and transmission of multidrug resistant (MDR) Klebsiella pneumoniae and Escherichia coli and its risk factors among preterm infants admitted to the neonatal intensive care unit (NICU)

BACKGROUND

Gastrointestinal carriage of multidrug resistant (MDR) Gram-negative bacilli, especially Klebsiella pneumoniae and Escherichia coli, was highly associated with severe nosocomial infections. The main objectives of this study were to determine the clonal relatedness of intestinal carriage and transmission risk factors of MDR E. coli and K. pneumoniae amongst preterm infants admitted to the neonatal intensive care unit (NICU).

METHODS

A prospective cohort study of preterm infants with gestational age < 37 weeks was conducted in the NICU of the University of Malaya Medical Centre (UMMC). Infants' stool specimens were collected on day 1 (meconium), week 1, week 2, week 8 and week 10 during their admission (from 1st June to 31st August 2017) until discharge. The presence and antibiotic resistance pattern of MDR E. coli and K. pneumoniae were determined. Strain clonality and relatedness were explored via pulsed-field gel electrophoresis (PFGE) fingerprints. The risk factors for MDR strains acquisition were evaluated using the Cox proportional-hazards model and Firth logistic regression.

RESULTS

A total of 139 stool specimens were obtained from 50 subjects. Twenty-six (52%) infants were colonized with MDR K. pneumoniae and/or E. coli. High clonal dissemination between two clusters of ESBL-producing K. pneumoniae strains was seen from PFGE profile. We detected a persistent, dominant, aminoglycosides-resistant strains cluster (cluster B), which harbored bla_TEM, bla_SHV, bla_OXA-1, bla_CTX-M-1, ompK35 and ompK36 genes. Infants born to women who were anemic in pregnancy [OR = 0.01 (CI = 0.00-0.39), P-value = 0.042] and infants exposed to penicillin/β-lactams group antibiotics during the first week of life [OR = 0.02 (CI = 0.02-0.32), P-value = 0.013] were found to have a lower risk of MDR K. pneumoniae and E. coli colonization.

CONCLUSIONS

The prevalence of dominant aminoglycosides-resistant strains cluster in the NICU is alarming. Awareness of and vigilance for the dominant cluster found will enable the reduction of cross-transmission amongst high-risk infants.

Efficacy of a coordinated strategy for containment of multidrug-resistant Gram-negative bacteria carriage in a Neonatal Intensive Care Unit in the context of an active surveillance program

Background

Antimicrobial resistance in neonatal intensive care unit (NICU) patients is a threat, due to the frequent use of antimicrobial treatment and invasive devices in fragile babies. Since 2014 an active surveillance program of multidrug-resistant Gram-negative bacteria (MDR-GNB) carriage has been in place in the five NICUs of Palermo, Italy. In 2017 an increase in the prevalence of MDR-GNB, and in particular of extended-spectrum β-lactamases-producing Klebsiella pneumoniae (ESBL-KP), was observed in “Civico” hospital NICU.

Aim

To assess the impact of a coordinated intervention strategy in achieving long-lasting reduction of MDR-GNB prevalence in the NICU.

Methods

Rectal swabs were obtained monthly and processed to detect MDR-GNB using standard methods. MDR-GNB were characterized by pulsed-field gel electrophoresis (PFGE). Since November 2017 the following intervention measures were applied: (a) two-months intensification of sample collection; (b) stakeholders meetings; (c) improvement of prevention measures and antimicrobial policies.

Findings

During the intensified microbiological surveillance MDR-GNB and ESBL-KP were detected in rectal swabs (34.8%; 23.2%), nasal swabs (24.6%; 14.5%), oral swabs (14.5%; 5.4%), milk samples (32.1%; 17.9%), pacifiers swabs (30.8%; 17.9%) and from sub-intensive room surfaces. Thirteen ESBL-KP strains isolated from clinical and environmental samples showed identical PFGE patterns. The prevalence of MDR-GNB and ESBL-KP carriage significantly decreased in the year after intervention compared to the previous year (20.6% vs 62.2%; p < 0.001 and 11.1% vs 57.8%; p < 0.001). MDR-GNB were not detected at all for three months and ESBL-KP for five months. Multivariate analysis of the principal exposure variables showed that admission in the post-intervention period significantly reduced the risk of MDR-GNB carriage (adj-OR = 0.21, 95% CI = 0.076–0.629; p < 0.001).

Conclusions

MDR-GNB broadly circulate in NICU setting, they can colonize different body sites and spread through various vehicles. A coordinated strategy of multiple interventions with active cooperation between epidemiologists and clinicians in the NICU can effectively reduce their circulation and in particular the carriage of the most dangerous ESBL-KP strains.

Can breastfeeding protect against antimicrobial resistance?

BACKGROUND

The proportion of infections among young children that are antimicrobial-resistant is increasing across the globe. Newborns may be colonized with enteric antimicrobial-resistant pathogens early in life, which is a risk factor for infection-related morbidity and mortality. Breastfeeding is actively promoted worldwide for its beneficial impacts on newborn health and gut health. However, the role of breastfeeding and human milk components in mitigating young children's carriage of antimicrobial-resistant pathogens and antibiotic resistance genes has not been comprehensively explored.

MAIN BODY

Here, we review how the act of breastfeeding, early breastfeeding, and/or human milk components, such as the milk microbiota, secretory IgA, human milk oligosaccharides, antimicrobial peptides, and microRNA -bearing extracellular vesicles, could play a role in preventing the establishment of antimicrobial-resistant pathogens in young children's developing gut microbiomes. We describe findings from recent human studies that support this concept.

CONCLUSION

Given the projected rise in global morbidity and mortality that will stem from antimicrobial-resistant infections, identifying behavioral or nutritional interventions that could decrease children's susceptibility to colonization with antimicrobial-resistant pathogens may be one strategy for protecting their health. We suggest that breastfeeding and human milk supplements deserve greater attention as potential preventive measures in the global effort to combat antimicrobial resistance, particularly in low- and middle-income settings.

Multilocus Variable-Number Tandem-Repeat Analysis for Geno-typing of Escherichia coli Strains Isolated from Hospital Wastewater, Tehran, Iran

Background:

Escherichia coli is one of the most frequent causes of many common bacterial infections. As a potential reservoir, hospital wastewater is considered for the dissemination of bacterial pathogens such as E. coli. Therefore, research on hospital waste’s bacteria by low-cost, rapid and easy molecular typing methods such as multilocus variable-number tandem-repeat analysis (MLVA) can be helpful for the study of epidemics.

Methods:

E. coli strains were isolated from hospital wastewater sources in Tehran, Iran, over a 24-month sampling period (Jun 2014- Jun 2016) and identified by standard bacteriological methods. The diversity of repeated sequences of seven variable-number tandem-repeat (VNTR) loci was studied by MLVA method base on polymerase chain reaction (PCR).

Results:

Overall, 80 E. coli isolates were discriminated into 51 different genotypes. Analysis of the MLVA profiles using a minimum spanning tree (MST) algorithm showed two clonal complexes with 71 isolates and only nine isolates were stayed out of clonal complexes in the form of a singleton. High genotypic diversity was seen among E. coli strains isolated from hospital wastewaters; however, a large number of isolates showed a close genetic relationship.

Conclusion:

MLVA showed to be a rapid, inexpensive and useful tool for the analysis of the phylogenetic relationships between E. coli strains under the study.

Antibiotic Resistance in the Neonatal Intensive Care Unit

Antibiotic-resistant bacteria are an increasing problem in the NICU. Ineffective empiric antibiotic therapy is associated with increased risk for morbidity and mortality. Organisms that are resistant to multiple antimicrobial agents (multidrug-resistant organisms) are particularly problematic. These organisms may be transmitted to infants if infection control practices are not adhered to, or they may be created by antibiotic exposure. Therefore, meticulous infection prevention-including hand hygiene, surveillance cultures, contact precautions, and selective decolonization-and antibiotic stewardship are important strategies to minimize drug resistance in the NICU.

Colonization of Mice With Amoxicillin-Associated Klebsiella variicola Drives Inflammation via Th1 Induction and Treg Inhibition

β-Lactam antibiotics can increase the resistance and virulence of individual intestinal microorganisms, which may affect host physiology and health. Klebsiella, a crucial gut inhabitant, has been confirmed to be resistant to most β-lactam antibiotics and contributes to the etiology of inflammatory bowel disease (IBD). In this study, the influence of amoxicillin (AMO) on Klebsiella and its role in colitis was investigated in an antibiotic cocktail (ABx) murine model. The results suggested that a 7-day AMO treatment significantly enriched the abundance of Klebsiella and enhanced serum resistance, antibiotic resistance, and biofilm formation ability of Klebsiella variicola (K. variicola) compared to the wild-type strain in the control group mice. Colonization of mice with the AMO-associated K. variicola could induce Th1 cells and inhibit Treg differentiation to promote inflammation in ABx murine model. In addition, inoculation of AMO-associated K. variicola in dextran sodium sulfate (DSS)-induced colitis murine model mice also confirmed that K. variicola colonization exacerbated inflammation as assessed by increased TNF-α, IFN-γ, IL-17a, and disease activity (DAI) levels; decreased colon length and bodyweight; and a disrupted Th1/Treg balance. The results of our study demonstrate that AMO enhances Klebsiella virulence in mice by disrupting the T cell equilibrium to exacerbate colitis, thereby providing a reference for proper antibiotic prescription.

Antimicrobial Susceptibility Trends among Pathogens Isolated from Blood: A 6-Year Retrospective Study from a Tertiary Care Hospital in East Sikkim, India

Background  Bloodstream infections (BSIs) are one of the frequent nosocomial infections among hospitalized patients. To understand the local epidemiology and evolving antimicrobial drug resistance of blood-borne pathogens, we analyzed the distribution and antibiotic sensitivity profile of organisms causing BSI in our hospital-based study. Materials and Methods  We reviewed retrospective data of laboratory-confirmed BSIs, from January 2013 to December 2018. Causative organisms and their antibiotic susceptibility profile of primary and secondary BSI reports were determined from BacT/Alert and Vitek systems findings (bioMérieux). A 6-year multidrug resistance indexing was done to document the resistance pattern of the commonly isolated organisms. Results  A total of 1,340 (10.2%) BSIs were reported from 13,091 blood cultures. Organisms were frequently isolated from the younger population (≤20 years), especially from ages < 1 year (20.8% of total BSIs). Majority of pathogens were bacterial (97.1%) whereas 2.9% were fungal in origin. Monomicrobial growth was recorded in over 98% of BSIs. Gram-positive and gram-negative bacteria isolated were 518 (39.8%) and 783 (60.2%), respectively. Commonly isolated organisms were coagulase-negative Staphylococci (29.4%), Escherichia coli (19.8%), Klebsiella species (13.5%), Salmonella species (9.4%), and Staphylococcus aureus (7.5%). Multidrug-resistance index was observed highest in Acinetobacter species followed by Pseudomonas aeruginosa and S. aureus . Conclusion  Overall, there has been a gradual decline in the reporting of BSI. However, infections by gram-negative bacilli and multidrug-resistant organisms remain persistently high. Ages < 20 years were the vulnerable group, with infants < 1 year contributing to the maximum number of BSI cases caused by both bacteria and fungi. Therefore, additional methods are required to study the origin and causation of these infections, particularly among vulnerable patients.

High Carriage Rates of Multidrug-Resistant Gram-Negative Bacteria in Neonatal Intensive Care Units From Ghana

Background

Carriage of multidrug resistant (MDR) Gram-negative bacteria (GN) in hospitalized neonates may increase the risk of difficult-to-treat invasive infections at neonatal intensive care units (NICUs). Data on MDRGN carriage among hospitalized newborns in Africa are limited.

Methods

We conducted a cross-sectional study at the NICUs of 2 tertiary hospitals in Ghana. Swabs from the axilla, groin, perianal region, and the environment were cultured, GN were identified, and antibiotic susceptibility was tested. We obtained blood culture isolates from neonates with sepsis. Whole-genome sequencing was used to characterize carbapenemase-producing Klebsiella pneumoniae. Typing was done by multilocus sequence typing (MLST) and single nucleotide polymorphism (SNP) analysis.

Results

A total of 276 GN were isolated from 228 screened neonates. Pathogenic GN were cultured in 76.8% (175 of 228) of neonates. Klebsiella spp (41.7%; 115 of 276) and Escherichia coli (26.4%; 73 of 276) were the commonest organisms. Carriage rates of MDRGN and third-generation cephalosporin resistant organisms were 49.6% (113 of 228) and 46.1% (105 of 228), respectively. Among Klebsiella spp, 75.6% (87 of 115) phenotypically expressed extended-spectrum β-lactamase activity, whereas 15.6% expressed carbapenemase and harbored bla-_OXA-181 and bla-_CTX-M-15. Overall, 7.0% (16 of 228) of neonates developed GN bloodstream infection. In 2 of 11 neonates, sequencing showed the same identity between carriage and the bloodstream isolate. Length of stay before specimen collection and antibiotic use were independently associated with carriage rates, which increased from 13% at admission to 42% by day 2 and reached a plateau at 91% by day 15.

Conclusions

High carriage rates of MDRGN, including carbapenemase-producing enterobacterales may be an emerging problem in NICUs in Africa.

Trends, risk factors and outcomes of healthcare-associated infections in a neonatal intensive care unit in Italy during 2013-2017

Background

Healthcare-associated infections (HAIs) occur frequently in intensive care units (NICUs). The aim of this study was to analyze the results of surveillance of HAIs in a III level NICU in Naples, Italy during 2013–2017 and to compare with those obtained during 2006–2010.

Methods

The surveillance included 1265 neonates of all birth weight (BW) classes with > 2 days NICU stay. Infections were defined using standard Centers for Disease Control and Prevention definitions adapted to neonatal pathology.

Results

A total of 125 HAIs were registered during 2013–2017 with a frequency of 9.9% and an incidence density of 3.2 per 1000 patient days. HAIs occurred in all BW classes with a decreasing trend from the lowest to the highest BW classes (p = < 0.001). Central line-associated blood stream infection (CLABSI) was the most frequent infection (69.6%), followed by ventilator associated pneumonia (VAP) (20%), urinary tract infection (UTI) (8.8%) and necrotizing enterocolitis (NEC) (1.6%). Also, CLABSI and VAP incidence density decreased from lower to highest BW classes showing a significant trend (p = 0.007). Most frequent pathogens responsible for CLABSI were: Coagulase-negative staphylococci (CONS) (25.3%), Candida parapsilosis (21.8%), Pseudomonas aeruginosa (5.7), Escherichia coli and Klebsiella pneumoniae (6.8%). No microbiological diagnosis was achieved for 20.7% of CLABSI. Pseudomonas aeruginosa (28%), Stenotrophomonas maltophilia (20%), and CONS (20%) were the most frequent pathogens responsible for VAP. CLABSI incidence density showed no differences between 2006 and 2010 and 2013–2017, while VAP incidence density for the 751–100 g BW class was higher during 2006–2010 than during 2013–2017 (p = 0.006). A higher incidence of the CLABSI caused by Gram positive bacteria (p = 0.002) or by undetermined etiology (p = 0.01) was observed during 2013–2017 than during 2006–2010, while a significant lower incidence of VAP caused by Gram-negative bacteria was found during 2013–2017 than during 2006–2010 (p = 0.007).

Conclusion

HAIs in the NICU developed in all BW classes with a decreasing trend from the lowest to the highest BW classes in both study periods. Differences in the aetiology of CLABSI and VAP were found between the two study periods. This reinforces the importance of HAIs surveillance protocol in the NICU, which monitors microbiological isolates and use of medical devices for all BW classes of neonates.

An Unsettled Promise: The Newborn Piglet Model of Neonatal Acute Respiratory Distress Syndrome (NARDS). Physiologic Data and Systematic Review

Despite great advances in mechanical ventilation and surfactant administration for the newborn infant with life-threatening respiratory failure no specific therapies are currently established to tackle major pro-inflammatory pathways. The susceptibility of the newborn infant with neonatal acute respiratory distress syndrome (NARDS) to exogenous surfactant is linked with a suppression of most of the immunologic responses by the innate immune system, however, additional corticosteroids applied in any severe pediatric lung disease with inflammatory background do not reduce morbidity or mortality and may even cause harm. Thus, the neonatal piglet model of acute lung injury serves as an excellent model to study respiratory failure and is the preferred animal model for reasons of availability, body size, similarities of porcine and human lung, robustness, and costs. In addition, similarities to the human toll-like receptor 4, the existence of intraalveolar macrophages, the sensitivity to lipopolysaccharide, and the production of nitric oxide make the piglet indispensable in anti-inflammatory research. Here we present the physiologic and immunologic data of newborn piglets from three trials involving acute lung injury secondary to repeated airway lavage (and others), mechanical ventilation, and a specific anti-inflammatory intervention via the intratracheal route using surfactant as a carrier substance. The physiologic data from many organ systems of the newborn piglet—but with preference on the lung—are presented here differentiating between baseline data from the uninjured piglet, the impact of acute lung injury on various parameters (24 h), and the follow up data after 72 h of mechanical ventilation. Data from the control group and the intervention groups are listed separately or combined. A systematic review of the newborn piglet meconium aspiration model and the repeated airway lavage model is finally presented. While many studies assessed lung injury scores, leukocyte infiltration, and protein/cytokine concentrations in bronchoalveolar fluid, a systematic approach to tackle major upstream pro-inflammatory pathways of the innate immune system is still in the fledgling stages. For the sake of newborn infants with life-threatening NARDS the newborn piglet model still is an unsettled promise offering many options to conquer neonatal physiology/immunology and to establish potent treatment modalities.

Transmission of multidrug-resistant Gram-negative bacteria from colonized mothers to their infants: a systematic review and meta-analysis

BACKGROUND

Neonatal sepsis remains a leading cause of neonatal mortality. Maternal bacterial colonization plays a major role in transmission to the infant, with potential for subsequent development of neonatal sepsis with maternally derived strains.

AIM

To review the molecular evidence supporting transmission of multidrug-resistant Gram-negative bacteria (MDR-GNB) from colonized mothers to their infants and the risk factors for MDR-GNB transmission.

METHODS

PubMed and Scopus were searched for studies investigating the mechanisms, risk factors for and/or scale of transmission of MDR-GNB from colonized mothers to their infants. Random effects meta-analyses were performed to determine pooled proportions of MDR-GNB transmission and the neonatal outcomes of transmission.

FINDINGS

Eight studies were included in the narrative description and six in the meta-analysis. Five studies used pulsed-field gel electrophoresis to assess relatedness of isolates from colonized mothers and their infants. Pooled proportion of MDR-GNB transmission from colonized mothers to their infants was 27% (95% confidence interval (CI): 8-47%). Extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae were the most frequently studied MDR-GNB pathogens transmitted between mother-infant pairs. Following mother-to-infant transmission of an MDR-GNB pathogen, the pooled proportion for the outcome of neonatal colonization was 19% (95% CI: 3-35%).

CONCLUSION

This systematic review strongly supports MDR and/or ESBL Enterobacteriaceae transmission from colonized mothers to their infants, with subsequent infant colonization. The risk factors contributing to transmission of MDR-GNB between colonized mothers and their infants warrants further research.

Genomic Insights into Two Colistin-Resistant Klebsiella pneumoniae Strains Isolated from the Stool of Preterm Neonate During the First Week of Life

Background: Klebsiella pneumoniae is a major opportunistic pathogen frequently associated with nosocomial infections, and often poses a major threat to immunocompromised patients. In our previous study, two K. pneumoniae (K36 and B13), which displayed resistance to almost all major antibiotics, including colistin, were isolated. Both isolates were not associated with infection and isolated from the stools of two preterm neonates admitted to the neonatal intensive care unit (NICU) during their first week of life. Materials and Methods: In this study, whole genome sequencing was performed on these two clinical multidrug resistant K. pneumoniae. We aimed to determine the genetic factors that underline the antibiotic-resistance phenotypes of these isolates. Results: The strains harbored bla_SHV-27, bla_SHV-71, and oqxAB genes conferring resistance to cephalosporins, carbapenems, and fluoroquinolones, respectively, but not harboring any known plasmid-borne colistin resistance determinants such as mcr-1. However, genome analysis discovered interruption of mgrB gene by insertion sequences gaining insight into the development of colistin resistance. Conclusion: The observed finding that points to a scenario of potential gut-associated resistance genes to Gram negative (K. pneumoniae) host in the NICU environment warrants attention and further investigation.

Effect of chlorhexidine bathing on colonization or infection with Acinetobacter baumannii: a systematic review and meta-analysis

Healthcare-associated infections (HAIs) caused by multi-drug-resistant Gram-negative bacteria (MDRGNB) have increased prevalence in intensive care units (ICUs). A common strategy to prevent HAIs is bathing patients with chlorhexidine gluconate (CHG). However, the effectiveness of CHG bathing against multidrug-resistant Acinetobacter baumannii (MDRAB) is still controversial. The aim of this study was to perform a systematic review and meta-analysis of the effectiveness of CHG bathing on Acinetobacter baumannii colonization and infection in the ICU setting. A systematic literature search of PubMed, EMBASE, Web of Science and CINAHL was performed from inception through to June 2018. Randomized controlled trials (RCTs), pre-post studies, or interrupted time series (ITS) studies were included. The numbers of patients with/without colonization or infection of A. baumannii in the experimental or control groups were extracted from each study. Quality assessment was performed by the related instruments of National Institute of Health. Pooled risk ratios (RRs) were calculated using the random-effects model. One RCT and 12 pre-post or ITS studies comprising 18,217 patients were included, of which 8069 were in the CHG bathing arm and 9051 in the control arm. CHG bathing was associated with a reduced colonization of A. baumannii (RR, 0.66; 95% confidence interval: 0.57-0.77; P<0.001). Chlorhexidine at 4% showed a better effect than 2% chlorhexidine (meta-regression P=0.044). CHG bathing was associated with a non-significant reduction of infection (pooled RR 0.41, 95% CI: 0.13-1.25). This study suggests that CHG bathing significantly reduces colonization of A. baumannii in the ICU setting. However, more trials are needed to confirm whether CHG bathing can reduce infections with A. baumannii.

The impact of paediatric antimicrobial stewardship programmes on patient outcomes

PURPOSE OF REVIEW

Although there has been an unprecedented global effort to reduce the spread of antimicrobial resistance, little emphasis has been placed on children. This review aims to evaluate the impact of paediatric antimicrobial stewardship programmes as well as providing a practical approach for effectively implementing them in community-based settings and in hospitals.

RECENT FINDINGS

Although rates of serious bacterial infection are low in children, the rates of antimicrobial use and resistance are comparable with adults. Different strategies are required to implement antimicrobial stewardship in community-based settings compared to in hospitals. Nationally coordinated, whole-system approaches have achieved long-term, sustainable reductions in antimicrobial prescribing, as well as reductions in resistance rates at population level, with no evidence of an increase in rate of serious infection or bacterial complications.

SUMMARY

Antimicrobial stewardship programmes in neonates and children have unique characteristics and issues. There is currently no consensus on how to measure consumption of antimicrobials in neonates and children. This is a research priority. Benchmarking and clinical networks in neonates and paediatrics are important to share practice and drive best use of antimicrobials.

Multidrug-resistant Gram-negative Bacterial Bloodstream Infections in Children's Hospitals in Japan, 2010-2017

BACKGROUND

The risk factors of multidrug-resistant (MDR) Gram-negative bacilli (GNB) bloodstream infection (BSI) are not yet known in children. Our aim was to evaluate risk factors and outcomes associated with MDR GNB BSI in children.

METHODS

Patients with GNB BSI were enrolled between April 2010 and March 2017 at 8 children's hospitals in Japan. Clinical and microbiologic data were collected retrospectively. The risk factors and outcomes of MDR and non-MDR GNB BSI were compared.

RESULTS

In total, 629 GNB BSI episodes met the case definition. The median age and proportion of males were 2 years (interquartile range, 0.3-8.7) and 50.7%, respectively. An underlying disease was found in 94% of patients. The proportion of BSI cases that developed >48 hours after admission was 76.2%. MDR comprised 24.5% of BSI cases. The MDR rate did not change over time (P = 0.540). The effective coverage rate of the initial empiric therapy for the MDR and non-MDR BSI cases was 60.4% and 83.4%, respectively (P < 0.001). The all-cause mortality rate at 28 days for all BSI, MDR-BSI and non-MDR BSI cases was 10.7%, 13.6% and 9.7%, respectively (P = 0.167). MDR BSI was independently associated with cancer chemotherapy within 30 days (odds ratio [OR] 43.90), older age (OR 1.05) and admission to the neonatal ward (OR 0.019).

CONCLUSIONS

One-fourth of GNB BSI cases were MDR. Cancer chemotherapy and older age were risk factors for MDR GNB BSI in children's hospitals. MDR did not increase the all-cause mortality rate.

The microbiota of the bilio-pancreatic system: a cohort, STROBE-compliant study

Background: The gut microbiota play an essential role in protecting the host against pathogenic microorganisms by modulating immunity and regulating metabolic processes. In response to environmental factors, microbes can hugely alter their metabolism. These factors can substantially impact the host and have potential pathologic implications.  Particularly pathogenic microorganisms colonizing pancreas and biliary tract tissues may be involved in chronic inflammation and cancer evolution.

Purpose: To evaluate the effect of bile microbiota on survival in patients with pancreas and biliary tract disease (PBD).

Patients and Methods: We investigated 152 Italian patients with cholelithiasis (CHL), cholangitis (CHA), cholangiocarcinoma (CCA), gallbladder carcinoma (GBC), pancreas head carcinoma (PHC), ampullary carcinoma (ACA), and chronic pancreatitis (CHP). Demographics, bile cultures, therapy, and survival rates were analyzed in cohorts (T₁ death <6 months; T₂ death <12 months; T₃ death <18 months, T_3S alive at 18 months).

Results: The most common bacteria in T₁ were E. coli, K. pneumoniae, and P. aeruginosa. In T₂, the most common bacteria were E. coli and P. aeruginosa. In T₃, there were no significant bacteria isolated, while in T_3S the most common bacteria were like those found in T₁. E. coli and K. pneumoniae were positive predictors of survival for PHC and ACA, respectively. E. coli, K. pneumoniae, and P. aeruginosa showed a high percentage of resistant bacteria to 3CGS, aminoglycosides class, and quinolone group especially at T₁ and T₂ in cancer patients.

Conclusions: An unprecedented increase of E. coli in bile leads to a decrease in survival. We suggest that some strains isolated in bile samples may be considered within the group of risk factors in carcinogenesis and/or progression of hepato-biliary malignancy. A better understanding of bile microbiota in patients with PBD should lead to a multifaceted approach to rapidly detect and treat pathogens before patients enter the surgical setting in tandem with the implementation of the infection control policy.

A cost analysis of active surveillance culture in a neonatal intensive care unit

Active surveillance culture (ASC) in neonatal intensive care units (NICUs) has been implemented to monitor horizontal transmission and choose appropriate antimicrobials when neonates experience late-onset infections (LOIs). To perform a cost analysis of ASC in the NICU, we evaluated data from a NICU ward in a Japanese community hospital. This was a retrospective study of neonates admitted to the NICU of Nara Prefecture General Medical Center, Nara City, Japan, from April 2012 to May 2017. We implemented biweekly ASC (nasal, stool and umbilical cultures) during this period. We assessed the detection rate for methicillin-sensitive and -resistant S. aureus (MSSA and MRSA) in each culture and reviewed the cases of LOI. Among the 785 cases, MSSA and MRSA were detected in 158 and 75 cases, respectively. Nasal culture was the most sensitive method for detecting MSSA and MRSA. Three cases benefitted from changing the empiric treatment based on previous ASC results, with an annual cost of ¥808,331 (£5773.80 or $7282.30) for ASC. The total cost per one benefited case during the study period was calculated as ¥1,392,126 (£9943.80 or $12,541.70). The total cost per benefited case in risk factor targeted ASC, nasal culture targeted ASC and MRSA-targeted ASC was ¥1,332,264 (£9516.20 or $12,002.30), ¥692,222 (£4944.40 or $6236.20) and ¥858,547 (£6132.50 or $7734.70), respectively. Considering the frequency of S. aureus detection and the cost of each culture, our ASC was modified to use only nasal cultures. This study suggests that the cost performance of ASC should be evaluated with consideration of the characteristics of each NICU.

Antibiotic therapy in neonates and impact on gut microbiota and antibiotic resistance development: a systematic review

Objectives

To systematically review the impact of antibiotic therapy in the neonatal period on changes in the gut microbiota and/or antibiotic resistance development.

Methods

Data sources were PubMed, Embase, Medline and the Cochrane Database, supplemented by manual searches of reference lists. Randomized controlled trials (RCTs) and observational studies were included if they provided data on different categories of antibiotic treatment (yes versus no, long versus short duration and/or broad- versus narrow-spectrum regimens) and subsequent changes in the gut microbiota and/or antibiotic resistance development. We evaluated risk of bias using the Cochrane Handbook, adapted to include observational studies. When appropriate, we used the vote-counting method to perform semi-quantitative meta-analyses. We applied the Grades of Recommendation, Assessment, Development and Evaluation approach to rate the quality of evidence (QoE). Study protocol registration: PROSPERO CRD42015026743.

Results

We included 48 studies, comprising 3 RCTs and 45 observational studies. Prolonged antibiotic treatment was associated with reduced gut microbial diversity in all three studies investigating this outcome (very low QoE). Antibiotic treatment was associated with reduced colonization rates of protective commensal anaerobic bacteria in four of five studies (very low QoE). However, all three categories of antibiotic treatment were associated with an increased risk of antibiotic resistance development, in particular MDR in Gram-negative bacteria, and we graded the QoE for these outcomes as moderate.

Conclusions

We are moderately confident that antibiotic treatment leads to antibiotic resistance development in neonates and it may also induce potentially disease-promoting gut microbiota alterations. Our findings emphasize the need to reduce unnecessary antibiotic treatment in neonates.

Surface colonization and subsequent development of infections with multi drug resistant organisms in a neonatal intensive care unit

BACKGROUND

This study analyzes colonization of the neonates in a NICU and incidence of these colonized infants developing infections due to the colonizers.

METHODS

Over a 12 month period, samples (surface swabs and rectal swabs) were obtained from all the infants admitted to NICU. The samples were cultured and examined for the presence of colonizers and especially for multi-drug resistant organisms.

RESULTS

From the total 533 patients, 473 (89%) neonates acquired colonizers and 60 (11%) did not. Of the 473 (89%) colonized infants, 57 (12%) developed infections of whom 33 (58%) were infected from the same organism as the colonizer and 24 (42%) neonates developed an infection that was different from the colonizer. 416 (88%) infants did not develop any infection inspite of being colonized.

CONCLUSIONS

The total numbers of babies contracting infection were more in the colonized group than the non-colonized. Other factors like gestational age and preterm may have played a role in development of infection in addition to colonization in these babies. Screening for the presence of MDRO colonization may be of limited use in predicting infections in the colonized individual. However, knowledge of their presence results in implementation of strict infection control practices. This along with judicious uses of antimicrobials effectively reduces infections from colonized bacteria and more importantly prevent their spread.

Prospective surveillance of bacterial colonization and primary sepsis: findings of a tertiary neonatal intensive and intermediate care unit

BACKGROUND

Preterm infants and critically ill neonates are predisposed to nosocomial infections as sepsis. Moreover, these infants acquire commensal bacteria, which might become potentially harmful. On-ward transmission of these bacteria can cause outbreaks.

AIM

To report the findings of a prospective surveillance of bacterial colonization and primary sepsis in preterm infants and neonates.

METHODS

The results of the surveillance of bacterial colonization of the gut and the respiratory tract, targeting meticillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and Gram-negative bacteria from November 2016 to March 2018 were analysed. Bacterial colonization was compared to surveillance of sepsis.

FINDINGS

Six-hundred and seventy-one patients were admitted and 87.0 % (N=584) of the patients were screened; 48.3% (N=282) of the patients screened were colonized with at least one of the bacteria included in the screening; 26.2% of them (N=74) had multi-drug-resistant strains. A total of 534 bacterial isolates were found. The most frequently found species were Escherichia coli, Enterobacter cloacae, Klebsiella oxytoca and Klebsiella pneumoniae. Three MRSA but no VRE were detected. The surveillance detected a K. pneumoniae cluster involving nine patients. There were 23 blood-culture-confirmed sepsis episodes; 60.9% (N=14) were caused by staphylococci. Gram-negative bacteria (one Klebsiella aerogenes and two E. cloacae) caused three sepsis episodes which were preceded by colonization with the respective isolates.

CONCLUSIONS

Surveillance of colonization provided a comprehensive overview of species and antibiotic resistance patterns. It allowed early detection of a colonization cluster. Knowledge of colonization and surveillance of sepsis is useful for guiding infection control measures and antibiotic treatment.

[Research advances in rational use of antibiotics in neonates]

Antibiotics are commonly used in the neonatal intensive care unit (NICU), but unnecessary or long-time exposure to antibiotics early after birth can increase the risk of poor prognosis of neonates. Antibiotic treatment in the NICU often begins with empiric therapy, but no uniform standards have been established for the initiation and course of empiric therapy. In neonates with negative bacterial culture results and stable clinical manifestations, empiric antibiotic therapy should be terminated in a timely manner. There are significant differences in the use of antibiotics in different NICUs. A targeted antimicrobial stewardship program is an effective way for optimizing the use of antibiotics in the NICU.

Role of the Clinical Microbiology Laboratory in Antimicrobial Stewardship

For adequate antimicrobial stewardship, microbiology needs to move from the laboratory to become physically and verbally amenable to the caregivers of an institution. Herein, we describe the contributions of our microbiology department to the antimicrobial stewardship program of a large teaching hospital as 10 main points ranging from the selection of patients deemed likely to benefit from a fast track approach, to their clinical samples, or the rapid reporting of results via a microbiology hotline, to rapid searches for pathogens and susceptibility testing. These points should serve as guidelines for similar programs designed to decrease the unnecessary use of antimicrobials.

Assessment of the multiplex PCR-based assay Unyvero pneumonia application for detection of bacterial pathogens and antibiotic resistance genes in children and neonates

BACKGROUND

Pneumonia is a major healthcare problem. Rapid pathogen identification is critical, but often delayed due to the duration of culturing. Early, broad antibacterial therapy might lead to false-negative culture findings and eventually to the development of antibiotic resistances. We aimed to assess the accuracy of the new application Unyvero P50 based on multiplex PCR to detect bacterial pathogens in respiratory specimens from children and neonates.

METHODS

In this prospective study, bronchoalveolar lavage fluids, tracheal aspirates, or pleural fluids from neonates and children were analyzed by both traditional culture methods and Unyvero multiplex PCR.

RESULTS

We analyzed specimens from 79 patients with a median age of 1.8 (range 0.01-20.1). Overall, Unyvero yielded a sensitivity of 73.1% and a specificity of 97.9% compared to culture methods. Best results were observed for non-fermenting bacteria, for which sensitivity of Unyvero was 90% and specificity 97.3%, while rates were lower for Gram-positive bacteria (46.2 and 93.9%, respectively). For resistance genes, we observed a concordance with antibiogram of 75% for those specimens in which there was a cultural correlate.

CONCLUSIONS

Unyvero is a fast and easy-to-use tool that might provide additional information for clinical decision making, especially in neonates and in the setting of nosocomial pneumonia. Sensitivity of the PCR for Gram-positive bacteria and important resistance genes must be improved before this application can be widely recommended.

Predicting Multidrug-Resistant Gram-Negative Bacterial Colonization and Associated Infection on Hospital Admission

OBJECTIVE

Isolation of multidrug-resistant gram-negative bacteria (MDR-GNB) from patients in the community has been increasingly observed. A prediction model for MDR-GNB colonization and infection risk stratification on hospital admission is needed to improve patient care.

METHODS

A 2-stage, prospective study was performed with 995 and 998 emergency department patients enrolled, respectively. MDR-GNB colonization was defined as isolates resistant to 3 or more classes of antibiotics, identified in either the surveillance or early (≤48 hours) clinical cultures.

RESULTS

A score-assigned MDR-GNB colonization prediction model was developed and validated using clinical and microbiological data from 995 patients enrolled in the first stage of the study; 122 of these patients (12.3%) were MDR-GNB colonized. We identified 5 independent predictors: age>70 years (odds ratio [OR], 1.84 [95% confidence interval (CI), 1.06–3.17]; 1 point), assigned point value in the model), residence in a long-term-care facility (OR, 3.64 [95% CI, 1.57–8.43); 3 points), history of cerebrovascular accidents (OR, 2.23 [95% CI, 1.24–4.01]; 2 points), hospitalization within 1 month (OR, 2.63 [95% CI, 1.39–4.96]; 2 points), and recent antibiotic exposure (OR, 2.18 [95% CI, 1.16–4.11]; 2 points). The model displayed good discrimination in the derivation and validation sets (area under ROC curve, 0.75 and 0.80, respectively) with the best cutoffs of<4 and ≥4 points for low- and high-risk MDR-GNB colonization, respectively. When applied to 998 patients in the second stage of the study, the model successfully stratified the risk of MDR-GNB infection during hospitalization between low- and high-risk groups (probability, 0.02 vs 0.12, respectively; log-rank test, P<.001).

CONCLUSION

A model was developed to optimize both the decision to initiate antimicrobial therapy and the infection control interventions to mitigate threats from MDR-GNB.

Infect Control Hosp Epidemiol 2017;38:1216–1225

The potential role of microbiota for controlling the spread of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) in neonatal population

The spread of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) in the hospital and also the community is worrisome. Neonates particularly are exposed to the risk of ESBL-PE acquisition and, owing to the immaturity of their immune system, to a higher secondary risk of ESBL-PE-related infection. Reducing the risk of acquisition in the hospital is usually based on a bundle of measures, including screening policies at admission, improving hand hygiene compliance, and decreasing antibiotic consumption. However, recent scientific data suggest new prevention opportunities based on microbiota modifications.

Presence, distribution and molecular epidemiology of multi-drug-resistant Gram-negative bacilli from medical personnel of intensive care units in Tianjin, China, 2007-2015

BACKGROUND

Multi-drug-resistant Gram-negative bacteria (MDRGNB) have become an important cause of nosocomial infection in intensive care units (ICUs).

AIMS

To investigate the molecular epidemiology of MDRGNB isolated from medical personnel (MP) and non-medical personnel (NMP) at 69 ICUs in Tianjin, China.

METHODS

From April 2007 to October 2015, 2636 nasal and hand swab samples from 1185 MP and 133 NMP were cultured for GNB (including MDRGNB), meticillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). The susceptibilities of GNB to 14 antimicrobial agents were determined, and 80 MDRGNB were characterized using pulsed-field gel electrophoresis (PFGE) and dendrogram analysis.

FINDINGS

In total, 301 GNB were identified in 269 MP, including 109 MDRGNB isolates in 104 MP. Forty-two GNB were isolated from 39 NMP, which included 20 NMP with MDRGNB. Overall, 8.8% of MP were colonized with MDRGNB, which greatly exceeded colonization rates with MRSA (0.9%) and VRE (0.1%). Three pairs of Klebsiella pneumoniae and one pair of Enterobacter aerogenes were indistinguishable from each other, but the majority of isolate tests had distinct PFGE profiles.

CONCLUSIONS

The prevalence of MDRGNB was high among ICU MP in Tianjin, and greatly exceeded that of VRE and MRSA. There was no difference in the rates of nasal carriage of MDRGNB between MP and NMP, but NMP were significantly more likely to have hand colonization with MDRGNB. PFGE profiles showed that there was only limited sharing of strains of MDR E. aerogenes and K. pneumoniae between personnel.