Klebsiella pneumoniae bloodstream infections among neonates in a high-risk nursery in Cali, Colombia

The relationship between Gram-negative colonization and bloodstream infections in neonates: a systematic review and meta-analysis

OBJECTIVES

Neonates admitted to neonatal intensive care units (NICU) are at significant risk of developing bloodstream infections (BSIs). Gram-negative bacteria (GNB) both colonize and infect, but the association between these entities is unclear. By conducting a systematic literature review, we aimed to explore the impact of factors on the association between GN colonization and GN-BSI at both baby-level and unit-level.

METHODS

We searched Medline, Embase, and Cochrane Library. Observational cohort studies published after 2000 up to June 2016 reporting data on the total number of neonates (0-28 days) colonized with GNB assessed by rectal/skin swab culture and the total number of neonates with GN-BSI (same bacteria) were included. Studies were excluded if data on skin/rectal colonization, neonates, and GNB could not be identified separately. Meta-analyses along with multivariate meta-regression with a random-effect model were performed to investigate factors associated with the GN colonization and GN-BSI at baby-level and unit-level.

RESULTS

Twenty-seven studies fulfilled our inclusion criteria, 15 for the baby-level and 12 for the unit-level analysis. Study heterogeneity was high, with suboptimal overall quality of reporting assessed by the STROBE-NI statement (44.8% of items adequately reported). In 1984 colonized neonates, 157 (7.9%) developed GN-BSI compared with 85 of 3583 (2.4%) non-colonized neonates. Considerable heterogeneity was observed across studies. Four factors were included in the meta-regression model: gross domestic product (GDP), pathogen, outbreak, and frequency of screening. There was no statistically significant impact of these factors on GN colonization and GN-BSI in baby-level. We were unable to perform the multivariate meta-regression because of insufficient reported data for unit-level.

CONCLUSIONS

Study limitations include the small number and the high heterogeneity of the included studies. While this report shows a correlation between colonization and BSI risk, these data currently do not support routine screening for GNB. Analysis of large cohorts of colonized neonates with clinical outcomes is still needed to define the major determinants leading from colonization to infection.

Two outbreaks of ESBL-producing Klebsiella pneumoniae in a neonatal intensive care unit

BACKGROUND

In the present study, two epidemic episodes of extended spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae in the neonatal intensive care unit (NICU) were evaluated.

METHODS

Routine and surveillance culture samples were taken from seven neonates with signs of infection in the NICU of Selcuk University Faculty of Medicine between 10 March and 25 April 2011, and between 11 June and 30 September 2011.

RESULTS

ESBL-producing K. pneumoniae strains were isolated in six different samples (one wound, one blood, and four cerebrospinal fluid cultures) of the three neonates in the first episode and in 11 different samples (seven blood and four cerebrospinal fluid cultures) of the four neonates in the second episode. ESBL-producing K. pneumoniae was isolated from inguinal, axillar region, and stool samples of the nine colonized neonates in the second episode. It was determined on pulse field gel electrophoresis that all strains originated from two clones.

CONCLUSIONS

The deficiencies in the infection control measures in an NICU may transform into an epidemic rapidly. Therefore, periodic training, observation, and monitoring of compliance are important.

Estimating potential infection transmission routes in hospital wards using wearable proximity sensors

Background

Contacts between patients, patients and health care workers (HCWs) and among HCWs represent one of the important routes of transmission of hospital-acquired infections (HAI). A detailed description and quantification of contacts in hospitals provides key information for HAIs epidemiology and for the design and validation of control measures.

Methods and Findings

We used wearable sensors to detect close-range interactions (“contacts”) between individuals in the geriatric unit of a university hospital. Contact events were measured with a spatial resolution of about 1.5 meters and a temporal resolution of 20 seconds. The study included 46 HCWs and 29 patients and lasted for 4 days and 4 nights. 14,037 contacts were recorded overall, 94.1% of which during daytime. The number and duration of contacts varied between mornings, afternoons and nights, and contact matrices describing the mixing patterns between HCW and patients were built for each time period. Contact patterns were qualitatively similar from one day to the next. 38% of the contacts occurred between pairs of HCWs and 6 HCWs accounted for 42% of all the contacts including at least one patient, suggesting a population of individuals who could potentially act as super-spreaders.

Conclusions

Wearable sensors represent a novel tool for the measurement of contact patterns in hospitals. The collected data can provide information on important aspects that impact the spreading patterns of infectious diseases, such as the strong heterogeneity of contact numbers and durations across individuals, the variability in the number of contacts during a day, and the fraction of repeated contacts across days. This variability is however associated with a marked statistical stability of contact and mixing patterns across days. Our results highlight the need for such measurement efforts in order to correctly inform mathematical models of HAIs and use them to inform the design and evaluation of prevention strategies.

Trends in antibiotic susceptibility and incidence of late-onset Klebsiella pneumoniae neonatal sepsis over a six-year period in a neonatal intensive care unit in Karachi, Pakistan

INTRODUCTION

The incidence, change in antibiotic susceptibility, and risk factors associated with mortality of late-onset Klebsiella pneumoniae sepsis during 2006-2011, in a neonatal intensive care unit (NICU) of a developing country, were analyzed.

METHODS

The medical records of neonates with a discharge diagnosis of sepsis due to late-onset K. pneumoniae were retrieved. Demographic features, gestational age, date and year of admission, antibiotic susceptibility of isolates, and discharge status were recorded. The late-onset K. pneumoniae incidence per 1000 NICU admissions and risk factors for mortality due to late-onset K. pneumoniae sepsis are reported.

RESULTS

During the period 2006-2011, 104 of 2768 neonates developed late-onset K. pneumoniae sepsis. The overall incidence of late-onset K. pneumoniae sepsis was 3.7% (37/1000 NICU admissions), with the highest annual incidence being 53/1000 in 2010. Most cases were males (n = 64; 62%) and most were premature and very low birth weight (n = 68; 65%). More than 80% of isolates were resistant to ampicillin + clavulanic acid, gentamicin, aztreonam, and cephalosporins. An increasing trend of resistance to amikacin, fluoroquinolones, piperacillin/tazobactam, and imipenem was observed. In 2011, three-quarters (72%; n=13) of late-onset K. pneumoniae were CR K. pneumoniae. Seventeen (16%) neonates died. Being male (p = 0.06, adjusted odds ratio (AOR) 9.2, 95% confidence interval (CI) 1.3-66.9), having an extremely low birth weight (p = 0.01, AOR 6.1, 95% CI 0.8-44.4), having severe thrombocytopenia (p = 0.07, AOR 3.9, 95% CI 1.2-13.0), and failure to achieve microbiological clearance (p < 0.001, AOR 19.6, 95% CI 4.0-98.0) were significantly associated with mortality due to late-onset K. pneumoniae sepsis.

CONCLUSION

There has been a rise in carbapenem-resistant strains of late-onset K. pneumoniae, associated with an increased mortality and limited antibacterial choices. Antimicrobial stewardship and rigorous infection control measures seem to be the only way to limit the spread of these strains.

An outbreak of Klebsiella pneumoniae late-onset sepsis in a neonatal intensive care unit in Guatemala

BACKGROUND

Gram-negative bloodstream infections are an important cause of neonatal mortality. In October 2009, we investigated a Klebsiella spp outbreak in a neonatal intensive care unit in Guatemala.

METHODS

Probable cases were defined as a Klebsiella spp isolated from blood in neonates aged <28 days in the neonatal intensive care unit between October 1 and November 10, 2009; confirmed cases were identified as Klebsiella pneumoniae. Clinical data were abstracted from medical charts. K pneumoniae isolates were genotyped by pulsed-field gel electrophoresis (PFGE) and tested for antimicrobial susceptibility. Infection control practices were inspected.

RESULTS

There were 14 confirmed cases. The median age at onset of infection was 3 days (range, 2-8 days). Nine patients died (64%). K pneumoniae isolates were resistant to multiple antimicrobials. PFGE revealed 2 distinct clusters. Breaches in infection control procedures included inappropriate intravenous solution use and inadequate hand hygiene and contact precautions.

CONCLUSIONS

We report a K pneumoniae outbreak with high neonatal mortality in Guatemala. PFGE clustering suggested a common source possibly related to reuse of a single-use intravenous medication or solution. The risk for K pneumoniae bloodstream infections in neonates in low-resource settings where sharing of solutions is common needs to be emphasized.

Colonization of the gut with Gram-negative bacilli, its association with neonatal sepsis and its clinical relevance in a developing country

This study examined the pattern of colonization of the neonatal gut by aerobic Gram-negative bacilli (GNB) and evaluated the association between gut colonization and sepsis in the developing world. This deserves attention because of the high incidence of sepsis and the differences in hygienic environments in developing countries compared with the developed world. The study was carried out on neonates in a tertiary-care government hospital. Serial gut samples were analysed (gastric aspirates and stool samples) for GNB. Blood samples of cases showing clinical signs of sepsis were also analysed for septic screening and culture positivity. Antibiograms, serotyping and PFGE were carried out to evaluate the relatedness of the gut and blood isolates. A diverse array of GNB was isolated from the gut of the neonates, Klebsiella pneumoniae being most common, followed by Escherichia coli. The rate of isolation of GNB was consistently higher in stool samples compared with gastric aspirate samples. Colonization was influenced by a stay in the neonatal intensive care unit and by the prolonged use of a feeding tube. GNB were the cause of sepsis in the majority of cases, with K. pneumoniae being the most frequently isolated GNB from the blood. Acinetobacter baumannii, Escherichia coli, Enterobacter cloacae and Burkholderia cepacia were the other GNB recovered from the blood of the neonates. Neonates with GNB in the gut had a higher incidence of clinical sepsis than those without. In 50 % of cases, the genotypes of the organisms found in the blood were indistinguishable from their gut counterpart. These results show that the neonatal gut is colonized with a diverse array of GNB, and an association between gut colonization and neonatal sepsis was observed.

Sepsis-Related Mortality of Very Low Birth Weight Brazilian Infants: The Role of Pseudomonas aeruginosa

The aim of this study is to identify risk factors for sepsis-related mortality in low birth weight (<1500 g) infants. We performed retrospective cohort study to investigate risk factors for sepsis-related mortality in all neonates birth weight <1500 g admitted to Level III neonatal intensive care unit, Brazil, April 2001/September 2004. Of the 203 cases, 71 (35%) had sepsis. Of those, gram-positive was identified in 52/87 blood cultures (59.8%), the most common Coagulase-negative Staphylococcus (31/87; 35.5%). Gram-negative was present in 29 of the 87 positive blood cultures (33.3%), with Pseudomonas aeruginosa (8/87; 9.1%), the most frequent agent. Overall 21 of 71 infants with sepsis (29.6%) died. Risk factors for sepsis-related mortality were gestational age </=28 weeks, birth weight </=1000 g (9.6 times more often than birth weight >1000 g), five-minute Apgar </=7, gram-negative sepsis, mechanical ventilation (6.7 times higher than no use), and intravascular catheter. Sepsis-related mortality was due, mainly, to Pseudomonas aeruginosa; birth weight </=1000 g and mechanical ventilation were strong sepsis-related mortality predictors.

Port central venous catheters-associated bloodstream infection during outpatient-based chemotherapy

Central venous catheters (CVCs) are commonly used for the administration of intravenous chemotherapy in outpatient setting. Nevertheless, outbreaks of catheter-associated bloodstream infections had been reported from oncology centers. We describe a large outbreak of CVCs-associated Klebsiella oxytoca bloodstream infection, occurring in an oncology chemotherapy outpatient unit of northern Greece between October 2006 and May 2007. The outbreak involved approximately 10% of the patients with CVCs who were receiving home-based chemotherapy, and it represents the second larger outbreak of CVCs-associated BSIs due to Klebsiella oxytoca in oncology outpatient centers. We retrospectively analyzed the chain of investigations and prophylactic/diagnostic measures taken to eradicate the infection: (1) patients' chart audit, (2) estimation of the infection among asymptomatic patients, (3) implementation of the level of awareness of medical and paramedical personnel, (4) collection of samples from environment, medications and infusion materials, (5) critical appraisal of chemotherapeutical schemes and (6) cooperation with peripheral institutions. The isolation of Klebsiella oxytoca in a chemotherapy solution (infusional 5-FU in dextrose 5% solution within a 48 h pump) from a peripheral General Hospital and the prompt transmission of the data to the chemotherapy center played a key role for the management of the infection cluster. This is the first report that evidenced the detection of Klebsiella oxytoca within a chemotherapeutical preparation. Data transmission from peripheral hospitals to the central institution resulted in an important feedback that allowed a better estimation of the infection cluster and more tailored actions for the eradication of the infection.

Clinical practice guidelines for the diagnosis and management of intravascular catheter-related infection: 2009 Update by the Infectious Diseases Society of America

These updated guidelines replace the previous management guidelines published in 2001. The guidelines are intended for use by health care providers who care for patients who either have these infections or may be at risk for them.

Platelets, frozen plasma, and cryoprecipitate: what is the clinical evidence for their use in the neonatal intensive care unit?

Transfusion of blood components such as platelets, frozen plasma, and cryoprecipitate is a common practice in the neonatal intensive care unit. Although it is intuitive that these components would be transfused in the context of bleeding, their use in neonatology has often been on a prophylactic basis. Due to a lack of consensus guidelines regarding indications for transfusion, however, the neonatologist is left to his/her opinion as to when to transfuse. This article seeks to review the available evidence regarding the use of platelets, frozen plasma, and cryoprecipitate in neonates, as well as the risks associated with the administration of these products.

Intensive care unit outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae controlled by cohorting patients and reinforcing infection control measures

OBJECTIVE

To describe an outbreak of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae in the intensive care units (ICUs) of a hospital and the impact of routine and reinforced infection control measures on interrupting nosocomial transmission.

DESIGN

Outbreak report.

SETTING

A 31-bed intensive care department (composed of 4 ICUs) in a university hospital in Belgium.

INTERVENTION

After routine infection control measures (based on biweekly surveillance cultures and contact precautions) failed to interrupt a 2-month outbreak of ESBL-producing K. pneumoniae, reinforced infection control measures were implemented. The frequency of surveillance cultures was increased to daily sampling. Colonized patients were moved to a dedicated 6-bed ICU, where they received cohorted care with the support of additional nurses. Two beds were closed to new admissions in the intensive care department. Meetings between the ICU and infection control teams were held every day. Postdischarge disinfection of rooms was enforced. Broad-spectrum antibiotic use was discouraged.

RESULTS

Compared with a baseline rate of 0.44 cases per 1,000 patient-days for nosocomial transmission, the incidence peaked at 11.57 cases per 1,000 patient-days (October and November 2005; rate ratio for peak vs baseline, 25.46). The outbreak involved 30 patients, of whom 9 developed an infection. Bacterial genotyping disclosed that the outbreak was polyclonal, with 1 predominant genotype. Reinforced infection control measures lasted for 50 days. After the implementation of these measures, the incidence fell to 0.08 cases per 1,000 patient-days (rate ratio for after the outbreak vs during the outbreak, 0.11).

CONCLUSION

These data indicate that, in an intensive care department in which routine screening and contact precautions failed to prevent and interrupt an outbreak of ESBL-producing K. pneumoniae, reinforced infection control measures controlled the outbreak without major disruption of medical care.

Transfusion-transmitted Klebsiella pneumoniae fatalities, 1995 to 2004

Transfusion-transmitted bacterial sepsis is the third most common cause of transfusion-related fatalities reported to the Food and Drug Administration. Between October 1, 1995, and September 30, 2004, there were 665 reported transfusion fatalities. Eighty-five (13%) deaths were due to transfusion-transmitted bacterial infections, of which 58 (68%) were due to gram-negative organisms. The most common gram-negative organism associated with transfusion-transmitted deaths after receipt of platelets was Klebsiella pneumoniae. This article summarizes retrospectively the case series of deaths due to transfusion-transmitted K pneumoniae infection, reported to the Food and Drug Administration, 1995 to 2004. There were 12 deaths due to transfusion-transmitted K pneumoniae infection with 7 (58%) of the 12 cases occurring in 2002. Eleven deaths were caused by the transfusion of contaminated platelets and 1 death attributed to contaminated red blood cells. Extensive review of the seven 2002 fatality reports did not identify a common (shared) lot for items used during collection or processing of the blood product. In conclusion, in cases of suspected transfusion-transmitted septicemia, broad spectrum antibiotic coverage including coverage of gram-negative organisms should be considered. Strict adherence to infection control measures while collecting, processing, and handling all blood and blood components in both the clinical settings and in the laboratory should be followed. Further development of simple and effective test procedures for detecting bacteria in the blood is needed.

A simultaneous outbreak of Serratia marcescens and Klebsiella pneumoniae in a neonatal intensive care unit

We describe two concurrent outbreaks of Serratia marcescens and Klebsiella pneumoniae in a neonatal intensive care unit (NICU). Over a 16-month period, a total of 27 infants were either colonized (N=14) or infected (N=13). There were 15 cases of S. marcescens and 11 cases of K. pneumoniae. Both micro-organisms were involved in one fatal case. Seven preterm babies developed septicaemia, two had bacteraemia, three had respiratory infections and one had purulent conjunctivitis. The S. marcescens and K. pneumoniae isolates were investigated by three molecular methods: enterobacterial repetitive intergenic consensus polymerase chain reaction (PCR), arbitrary primed PCR with M13 primer, and random amplification of polymorphic DNA. Different patterns were found in the 16 S. marcescens epidemic isolates from 16 newborn infants. The major epidemic-involved genotype was linked to the first nine cases and this was subsequently replaced by different patterns. Eight different typing profiles were also determined for the 13 K. pneumoniae isolates from 12 newborn infants. Four K. pneumoniae bacteraemic strains proved to be identical. In conclusion, the typing results revealed that two different micro-organisms (S. marcescens and K. pneumoniae) were simultaneously involved in invasive nosocomial infections in preterm newborns. Two simultaneous clusters of cases were documented. Heterogeneous genotypes among both species were also demonstrated to be present in the NICU at the same time. A focal source for both micro-organisms was not identified but cross-transmission through handling was probably an important route in this outbreak. Strict adherence to handwashing policies, cohorting, isolation of colonized and infected patients, and rigorous environmental hygiene were crucial measures in the containment of the epidemic.

Nosocomial bacteremia in neonates related to poor standards of care

BACKGROUND

In developing countries, intravenous liquids are mixed and administered by nurses, sometimes under suboptimal infection control conditions. We hypothesized that outbreaks of infusate-associated neonatal bacteremias are common, and we evaluated whether they can be detected by vigilant microbiologic surveillance of infusates.

METHODS

We studied intravenous infusates administered to neonates in a Mexican hospital where mixtures of infusates were prepared in hospital wards. The study was performed in 3 stages: stage 1, initial culturing of in-use infusates under basal conditions; stage 2, prospective culturing during a cluster of clinical sepsis; and stage 3, final culturing once the outbreak was controlled.

RESULTS

In stage 1, 68 infusates were sterile, and 1 was contaminated with Staphylococcus aureus (1.45%), from 23 patients. In stage 2, of 182 infusates from 39 patients, 51 infusates (28%) were contaminated with Gram-negative rods. On the first day of stage 2, 11 of 15 infusates were contaminated with the same strain of Klebsiella pneumoniae, which continued to appear for 26 days. Another 4 strains of Gram-negative rods were also isolated during stage 2. The association between contaminated infusate and death was significant (odds ratio, 9.4; 95% confidence interval, 2-44.3; P < 0.001). Mixtures made by nurses were more likely contaminated than commercial preparations (odds ratio, 3.1; 95% confidence interval, 1.1-8.5; P = 0.037). In stage 3, there were 42 sterile infusates from 22 patients.

CONCLUSIONS

Our study suggests that poor standards of care common in hospitals from developing countries sometimes result in outbreaks of sepsis and death for newborn patients.

Hospital-acquired neonatal infections in developing countries

Hospital-born babies in developing countries are at increased risk of neonatal infections because of poor intrapartum and postnatal infection-control practices. We reviewed data from developing countries on rates of neonatal infections among hospital-born babies, range of pathogens, antimicrobial resistance, and infection-control interventions. Reported rates of neonatal infections were 3-20 times higher than those reported for hospital-born babies in industrialised countries. Klebsiella pneumoniae, other gram-negative rods (Escherichia coli, Pseudomonas spp, Acinetobacter spp), and Staphylococcus aureus were the major pathogens among 11,471 bloodstream isolates reported. These infections can often present soon after birth. About 70% would not be covered by an empiric regimen of ampicillin and gentamicin, and many might be untreatable in resource-constrained environments. The associated morbidity, mortality, costs, and adverse effect on future health-seeking behaviour by communities pose barriers to improvement of neonatal outcomes in developing countries. Low-cost, "bundled" interventions using systems quality improvement approaches for improved infection control are possible, but should be supported by evidence in developing country settings.