Increased prevalence of extended spectrum beta lactamase producers in neonatal septicaemic cases at a tertiary referral hospital

Subtyping β-lactamase-producing Escherichia coli strains isolated from patients with UTI by MLVA and PFGE methods

OBJECTIVES

Strain subtyping is an important epidemiological tool to trace contamination, determine clonal relationships between different strains, and the cause of outbreaks. Current subtyping methods, however, yield less than optimal subtype discrimination. Pulsed-field gel electrophoresis is the gold standard method for Escherichia coli and Multiple-Locus Variable-number tandem repeat Analysis is a rapid PCR-based method. The purpose of this study was to evaluate MLVA and PFGE methods for subtyping β -lactamase-producing E. coli strains isolated from urinary tract infections.

MATERIALS AND METHODS

Overall, 230 E. coli isolates from patients with urinary tract infections were examined for antimicrobial susceptibility testing. 10-loci and 7-loci MLVA and PFGE methods were used for molecular typing of β -lactamase-producing E. coli isolates.

RESULTS

Out of 230 isolates, 130 (56.5%) β -lactamase-producing E. coli isolates were found in this study. The diversity indices of the VNTR loci showed an average diversity of 0.48 and 0.54 for 7-loci and 10-loci MLVA, respectively. The discriminatory power of PFGE showed a value of 0.87. The discordance between the methods was high.

CONCLUSION

Our study showed that PFGE is more discriminatory than MVLA. MLVA is a PCR- based method and can generate unmistakable data, in contrast to PFGE. Optimization of polymorphic VNTR is essential to improve the discriminatory power of MLVA based on geographical region.

Changing trends in the bacteriological profiles and antibiotic susceptibility in neonatal sepsis at a tertiary children's hospital of China

BACKGROUND

Sepsis is a major cause of neonatal morbidity and mortality in developing countries, and early-onset sepsis has poor outcomes. The causative bacteria vary depending on the geographical location of the hospital. This study aimed to determine the changing trends of causative bacteria and antibiotic susceptibility in the past decade.

METHODS

This study retrospectively analyzed the blood culture of positive cases of early-onset sepsis admitted to the neonatal intensive care unit of our hospital between 2009 and 2018. The cases were divided into two phases, i.e., phase I (2009 to 2013) and phase II (2014 to 2018). Changing trends in the bacteriological profiles and antibiotic susceptibility were recorded and analyzed.

RESULTS

A total of 1,479 causative bacteria were detected. Gram-positive bacteria were isolated in 74.92% of the cases, and coagulase-negative Staphylococci (CoNS) (63.22%) was identified as the common isolate. Klebsiella pneumoniae (10.01%) followed by Escherichia coli (8.72%) were the dominant Gram-negative bacteria. Comparative analysis showed a significant reduction in CoNS. Among Gram-negative bacteria, K. pneumoniae was initially predominant but was replaced by E. coli in phase II. Gram-positive bacteria showed relatively high susceptibility to aminoglycosides and quinolones. K. pneumoniae exhibited higher resistance to cephalosporin compared with E. coli. Reduced sensitivity against the first- and second-generation antibiotics was observed in phase II.

CONCLUSIONS

The etiological profile of neonatal sepsis (NS) has undergone a significant change in the last decade. Antibiotic resistance has increased, and continuous surveillance for antibiotic susceptibility is required to ensure efficient therapeutic outcomes.

Trends of Antimicrobial Resistance of Sepsis Pathogens at a University Hospital in New Delhi, India

Knowledge of the aetiological agents and its susceptibility to antimicrobial agents enables the clinician to initiate appropriate empirical antimicrobial therapy and guides diagnostic procedures. The aims of the study were to identify prevalence of bacterial pathogens causing sepsis and observe their antimicrobial resistance trends in hospitalized patients. A prospective cohort study was conducted on patients of sepsis admitted at a university hospital over a period of six months. Pathogens were identified by morphological, biochemical and serological tests as per the American Society for Microbiology. Antibacterial sensitivity of bacterial strains isolated from clinically diagnosed sepsis was carried out by Kirby-Bauer disk diffusion method and interpreted according Clinical and Laboratory Standards Institute guidelines. The data were analyzed by using Statistical Package for Social Sciences, version 16.0 (SPSS 16.0, Chicago, IL, USA). Coagulase negative Staphylococcus (63.5%) and Staphylococcus aureus (23.1%) were the most frequently isolated Gram positive bacteria. Acinetobacter species (31%) and Salmonella typhi (24.1%) were the most frequently isolated Gram negative bacteria. Coagulase negative Staphylococcus showed significant resistance to ciprofloxacin and tetracycline. Acinetobacter species showed significant resistance to ampicillin, amoxicillin and amoxiclav. Salmonella typhi showed significant resistance to ampicillin, amoxicillin, cefotaxime, netilmicin and, tetracycline. Escherichia coli showed significant resistance to ampicillin and netilmicin. All the stains of Staphylococcus aureus were resistant to amoxicillin. Coagulase negative Staphylococcus and Acinetobacter species were predominant Gram positive and Gram negative bacteria, respectively, causing sepsis. Increasing rates of bacterial resistance to commonly use antimicrobial agents were observed.

Available evidence of antibiotic resistance from extended-spectrum β-lactamase-producing Enterobacteriaceae in paediatric patients in 20 countries: a systematic review and meta-analysis

OBJECTIVE

To make a systematic review of risk factors, outcomes and prevalence of extended-spectrum β-lactamase-associated infection in children and young adults in South-East Asia and the Western Pacific.

METHODS

Up to June 2018 we searched online databases for published studies of infection with extended-spectrum β-lactamase-producing Enterobacteriaceae in individuals aged 0-21 years. We included case-control, cohort, cross-sectional and observational studies reporting patients positive and negative for these organisms. For the meta-analysis we used random-effects modelling of risk factors and outcomes for infection, and meta-regression for analysis of subgroups. We mapped the prevalence of these infections in 20 countries and areas using available surveillance data.

FINDINGS

Of 6665 articles scanned, we included 40 studies from 11 countries and areas in the meta-analysis. The pooled studies included 2411 samples testing positive and 2874 negative. A higher risk of infection with extended-spectrum β-lactamase-producing bacteria was associated with previous hospital care, notably intensive care unit stays (pooled odds ratio, OR: 6.5; 95% confidence interval, CI: 3.04 to 13.73); antibiotic exposure (OR: 4.8; 95% CI: 2.25 to 10.27); and certain co-existing conditions. Empirical antibiotic therapy was protective against infection (OR: 0.29; 95% CI: 0.11 to 0.79). Infected patients had longer hospital stays (26 days; 95% CI: 12.81 to 38.89) and higher risk of death (OR: 3.2; 95% CI: 1.82 to 5.80). The population prevalence of infection was high in these regions and surveillance data for children were scarce.

CONCLUSION

Antibiotic stewardship policies to prevent infection and encourage appropriate treatment are needed in South-East Asia and the Western Pacific.

Clinical characteristics and epidemiology of sepsis in the neonatal intensive care unit in the era of multi-drug resistant organisms: A retrospective review

BACKGROUND

Sepsis in the neonatal intensive care unit (NICU) remains one of the most significant causes of morbidity and mortality, especially for preterm newborns. Multi-drug resistant organisms (MDROs) are emerging as important pathogens that cause neonatal sepsis in NICU. Therefore, studying the epidemiology, clinical features, and outcome caused by MDROs vs. non-MDROs, and identifying risk factors that may predispose patients to sepsis by MDROs are important.

METHODS

Episodes of blood culture-proven sepsis (age: 0-90 days) in the NICU at our institution from January 2012 to December 2015 were retrospectively reviewed. Collected data included demographics, signs at time of sepsis, laboratory values, microbiologic results, and final outcome. We compared clinical and laboratory data and final outcome for patients with sepsis due to MDROs vs. non-MDROs. Multivariate analysis was performed on variables with a P value of <0.05 from univariate analysis.

RESULTS

Sixty-eight episodes of sepsis (ages 0-54 days, median 7 days; 34 female; 81% premature) were caused by Gram-negative bacteria (n = 42; 62%), Gram-positive bacteria (n = 21; 31%), or Candida (n = 5; 7%). The most common organisms that were isolated were Acinetobacter baumannii (27%), Klebsiella pneumoniae (22%), coagulase-negative staphylococcus (CoNS) (18%), group B streptococcus (10%), and Escherichia coli (6%). Compared with non-MDROs (n = 16; 31%, excluding CoNS and Candida), MDROs (n = 35; 69%) were associated with higher mortality (P = 0.002) and more delay in providing targeted antimicrobial therapy (P = 0.002) (based on antimicrobial susceptibility tests). Sepsis due to the most resistant organisms (A. baumannii and K. pneumoniae Carbapenemase [KPC]-producing bacteria, n = 20; 39%) was associated with higher mortality (P = 0.001) and significantly associated with exposure to carbapenem and vancomycin before onset of sepsis (cases exposed = 13/20; 65%, P < 0.001).

CONCLUSION

MDROs are the most common cause of sepsis at our NICU and are associated with higher mortality compared with non-MDROs. Previous exposure to carbapenem and vancomycin was associated with sepsis caused by the most resistant organisms.

Prevalence of ESBL-Producing Enterobacteriaceae in Pediatric Bloodstream Infections: A Systematic Review and Meta-Analysis

Background

Pediatric bloodstream infections (BSIs) with Extended-Spectrum Beta-Lactamase- producing Enterobacteriaceae (ESBL-PE) are associated with worse clinical outcomes. We aimed to estimate the prevalence of and the mortality associated with ESBL-PE in this patient population.

Methods

A systematic review and meta-analysis using PubMed and EMBASE and included studies reporting the prevalence of ESBL-PE among confirmed BSIs in patients <19 years old.

Results

Twenty three (out of 1,718 non-duplicate reports) studies that provided data on 3,381 pediatric BSIs from 1996 to 2013 were included. The prevalence of ESBL-PE was 9% [95%CI (6, 13)] with an annual increase of 3.2% (P = 0.04). The prevalence was 11% [95%CI (6, 17)] among neonates, compared to 5% [95%CI (0, 14)] among children older than 28 days. The pooled prevalence was 15% in Africa [95%CI (8, 23)], 12% in South America [95%CI (5, 23)], 11% in India [95%CI (7, 17)], 7% in the rest of Asia [95%CI (0, 22)], 4% in Europe [95%CI (1, 7)] and 0% in Oceania [95%CI (0, 3)]. Importantly, the mortality in neonates with BSI due to ESBL-PE was 36% [95%CI (22, 51)], compared to 18% [95%CI (15, 22)] among all other neonates with BSI and this difference was statistically significant (P = 0.01).

Conclusions

In the pediatric population, the prevalence of BSI due to ESBL-PE is significant and is associated with increased mortality in neonates. Further studies are warranted to establish a high-risk group and the evaluation of preventive measures, such as antibiotic stewardship programs and infection control measures, in this population is urgently needed.

VEB-1 extended-spectrum β-lactamase-producing multidrug-resistant Proteus mirabilis sepsis outbreak in a neonatal intensive care unit in India: clinical and diagnostic implications

Introduction:

Extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, multidrug-resistant (MDR) pathogens, are increasingly implicated in nosocomial outbreaksworldwide, particularly in neonatal intensive care units (NICUs). Proteus mirabilis is an uncommon nosocomial pathogen causing sepsis in neonates.

Case Presentation:

We report an outbreak of ESBL-positive MDR P. mirabilis sepsis involving five babies within 10 days in a NICU, which was promptly detected and managed. The aim of this study was to characterize the molecular mechanism of resistance to third-generation cephalosporins (3GCs) in the bacteria. Surveillance cultures were collected from health-care personnel (hand swabs, urine) and the surrounding patient-care environment. Ribotyping was performed to determine the clonality of the strain. Thirteen P. mirabilis were recovered from the blood cultures of the five babies and surveillance cultures. Twelve isolates were positive for the VEB-1 ESBL type, and were susceptible only to ciprofloxacin and carbapenems. There was an unusual phenotypic synergy observed between the 3GCs and imipenem/cefoxitin. The source of infection was traced to a contaminated multidose vial. The outbreak was associated with a high mortality (80 %). A change of empirical antibiotic policy to ciprofloxacin, with strict infection control measures, brought the outbreak to an abrupt end.

Conclusion:

This is believed to be the first report of a nosocomial outbreak of VEB-1 ESBL-producing P. mirabilis sepsis in neonates from India. The present report of infection due to VEB-1-producing P. mirabilis, an uncommon pathogen for an epidemic in a neonatal unit, highlights the growing significance of such Gram-negative bacteria as a cause of infections in newborns. Epidemic spread in a neonatal unit of an ESBL-producing Proteus species, which also had an intrinsically reduced susceptibility to imipenem, and resistance to colistin and tigecycline, can be a threatening situation and can result in high neonatal mortality unless recognized and controlled in a timely manner.

Detection and characterization of extended-spectrum β-lactamases (blaCTX-M-1 and blaSHV ) producing Escherichia coli, Salmonella spp. and Klebsiella pneumoniae isolated from humans in Mizoram

Aim:

The present study was conducted to isolate and characterize the extended spectrum β-lactamases (ESBLs) producing enteric bacteria in human beings in Mizoram, India.

Materials and Methods:

Fecal samples were collected from human beings with or without the history of diarrhea from different hospitals of Mizoram. Samples were processed for isolation and identification of Escherichia coli, Salmonella and Klebsiella pneumoniae. All the isolates were subjected to antibiotic sensitivity assays. Phenotypically, ESBLs production ability was determined by double discs synergy test (DDST) method. ESBLs producing isolates were subjected to polymerase chain reaction (PCR) for detection of ESBLs genes. Plasmids were cured by acridine orange. Transfer of resistance from a donor to recipient strains was done by in vitro horizontal method.

Results:

A total of 414 enteric bacteria were isolated from 180 fecal samples (113 were from diarrheic patients and 67 were from non-diarrheic patients), of which 333 (80.44%), 52 (12.56%), and 29 (7.00%) were E. coli, K. pneumoniae and Salmonella spp., respectively. Double discs synergy test (DDST) exhibited 72 (21.62%) E. coli, 12 (23.08%) K. pneumoniae and 4 (13.79%) Salmonella spp. were ESBLs producers. Altogether, 24 (13.04%) isolates were found to be positive for at least one resistance genes under this study. A total of 36 (8.70%) E. coli, 4 (0.97%) K. pneumoniae and 2 (0.48%) Salmonella spp. were found to be positive for bla_CTX-M-1 gene by PCR. Similarly, 5 (1.21%) E. coli and 4 (0.97%) K. pneumoniae isolates were found to be positive for bla_SHV gene. A total of 3 (0.72%) K. pneumoniae isolates were recorded as positive for both bla_CTX-M-1 and bla_SHV genes. All the isolates were carrying plasmids ranging between 0.9 kb and ~30 kb. The resistance plasmid could not be transferred to a recipient by in vitro horizontal gene transfer method.

Conclusion:

ESBLs producing enteric bacteria are circulating in human population in North Eastern Region of India. Indiscriminate use of antibiotics should be avoided to control the menace of multidrug resistance bacteria in the environment, animals, and human beings.

Characterization of Multidrug Resistant Extended-Spectrum Beta-Lactamase-Producing Escherichia coli among Uropathogens of Pediatrics in North of Iran

Escherichia coli remains as one of the most important bacteria causing infections in pediatrics and producing extended-spectrum beta-lactamases (ESBLs) making them resistant to beta-lactam antibiotics. In this study we aimed to genotype ESBL-producing E. coli isolates from pediatric patients for ESBL genes and determine their association with antimicrobial resistance. One hundred of the E. coli isolates were initially considered ESBL producing based on their MIC results. These isolates were then tested by polymerase chain reaction (PCR) for the presence or absence of CTX, TEM, SHV, GES, and VEB beta-lactamase genes. About 30.5% of isolated E. coli was ESBL-producing strain. The TEM gene was the most prevalent (49%) followed by SHV (44%), CTX (28%), VEB (8%), and GES (0%) genes. The ESBL-producing E. coli isolates were susceptible to carbapenems (66%) and amikacin (58%) and showed high resistance to cefixime (99%), colistin (82%), and ciprofloxacin (76%). In conclusion, carbapenems were the most effective antibiotics against ESBl-producing E. coli in urinary tract infection in North of Iran. The most prevalent gene is the TEM-type, but the other resistant genes and their antimicrobial resistance are on the rise.

Isolation of MRSA, ESBL and AmpC - β -lactamases from Neonatal Sepsis at a Tertiary Care Hospital

BACKGROUND AND OBJECTIVES

The emergence of methicillin resistant Staphylococcus aureus (MRSA) and extended spectrum β-lactamases (ESBLs) in neonatal intensive care unit patients is increasing. This study aims to find out the bacteriological profile in neonatal sepsis and study their antimicrobial susceptibility pattern including detection of MRSA and ESBLs.

MATERIALS AND METHODS

This study was conducted for a period of one and a half years from January 2010 to June 2011 in a tertiary care hospital in Chennai. A total of 182 blood samples were collected using sterile precautions. They were processed following standard laboratory protocol. Antibiogram was done using appropriate antibiotics by Kirby-Bauer disc diffusion method. Isolated Staphylococcus aureus were tested for methicillin resistance using Cefoxitin disc (30μg), ESBL was detected using combined disc method, MIC reduction and Polymerase chain reaction, metallobetalactamases using EDTA and Amp-C beta lactamases using AmpC disc test. C-reactive protein (CRP) was estimated for all the cases.

RESULTS

Out of the 182 cases, 110 (60.4%) were culture positive. Fifty five (63.9 %) of early onset sepsis cases had Gram negative bacteria (GNB) and 19 (79.1%) of late onset sepsis cases had Gram positive bacteria. Out of the total pathogens, 31 (28.1%) were Klebsiella pneumoniae and 30 (27%) were Staphylococcus aureus. 17 (56.6 %) of Staphylococcus aureus were found to be MRSA and they were 100% sensitive to Vancomycin. 33 (67.3%) of Enterobacteriaceae were ESBL producers. ESBL isolates were 100% sensitive to Imipenem. Three (6.1%) of Enterobacteriaceae were AmpC producers and 3 (27.2%) of Pseudomonas aeruginosa were MBL producers. CRP was positive in 99 (54.3%) cases, out of which 94 (94.9%) were culture positive.

CONCLUSION

Klebsiella spp. and Staphylococcus aureus were the commonest bacteria causing neonatal sepsis in this centre. Multidrug resistance among the isolates was common. Early diagnosis and institution of specific antibiotics after studying the sensitivity pattern will help in reducing neonatal morbidity and mortality and prevent emergence of drug resistant strains.

Co-production of ESBL and AmpC β-Lactamases in Clinical Isolates of A. baumannii and A. lwoffii in a Tertiary Care Hospital From Northern India

BACKGROUND

Acinetobacter baumannii is an important cause of health care associated infections which are difficult to control and treat, because of widespread antimicrobial resistance which is possessed by this organism.

AIMS

The aim of the present study was to know the prevalence of ESBLs and AmpC β-lactamases in clinical isolates of Acinetobacter spp. which were cultured from various clinical specimens by using different phenotypic methods.

SETTINGS AND DESIGN

Study was conducted over a period of one year at the Microbiology Department of a tertiary care teaching hospital. A total of 100 consecutive, non-duplicate strains of Acinetobacter species which were isolated from various clinical samples were included.

MATERIALS AND METHODS

All the isolates were identified by standard microbiological procedures and antimicrobial susceptibility testing was done by Kirby-Bauer disc diffusion technique. Isolates which showed reduced susceptibilities to third generation cephalosporins were tested for ESBL production by CLSI double disc synergy method and also by using sulbactam as an inhibitory agent. Isolates which showed reduced susceptibilities to cefoxitin were tested for AmpC detection by doing AmpC disc test.

STATISTICAL ANALYSIS

SPSS, version 17 was used to calculate p-value. If the p-value was <0.05, it was considered to be significant.

RESULTS

Out of 100 isolates, 82 were Acinetobacter baumannii and 18 were Acinetobacter lwoffii. ESBL were mentioned in 4% of the Acinetobacter isolates and in 77% of the isolates by using clavulanic acid and sulbactam as inhibitory agents respectively. AmpC β-lactamase production was detected in 60% isolates of Acinetobacter spp. Co-production of both ESBL and AmpC enzymes were seen in 29% of the Acinetobacter strains.

CONCLUSION

Failure in detecting β-lactamases contributes to their uncontrolled spread and therapeutic failures. Hence, these β-lactamases should be detected routinely and they should be reported to clinicians in time, so that inappropriate use of antibiotics can be stopped in time.

"Neonatal Sepsis": Bacteria & their Susceptibility Pattern towards Antibiotics in Neonatal Intensive Care Unit

BACKGROUND

Neonatal sepsis is one of the most common causes of neonatal mortality and morbidity, particularly in the developing countries. Its causative bacteria and their respective sensitivity patterns are different in each hospital and region. The objective of this study was to determine the causative bacteria and pattern of susceptibility to antibiotics in NICU of a tertiary care centre, which in turn may help in implementation of empirical therapy.

MATERIAL AND METHODS

This prospective study was carried out at a medical college during the period from 1st April 2011 to 31st March 2013. A total of 364 cases of suspected sepsis were admitted in our NICU during the mentioned period. Out of which, 137 cases were positive for culture. All the neonates of suspected sepsis were screened by using a panel consisting of CRP, ANC, I/T ratio, micro ESR and culture and sensitivity.

RESULTS

A total of 137 cultures were found to be positive out of 364 cases. The most common organism isolated was Staphylococcus aureus (37.22%) followed by Klebsiella pneumoniae (27.01%) and Escherichia coli (19.70%). Other organisms were much less in number, which included pathogenic Streptococci, Coagulase negative Staphylococci (CoNS), Pseudomonas, Acinetobacter and Enterobacter species. The gram positive organisms except Streptococci displayed a high degree of resistance to most penicillins and ciprofloxacin but were sensitive to vancomycin, amikacin and cefepime. There was a high incidence of resistance noted with ampicillin, gentamicin and ciprofloxacin amongst most gram negative organisms' where-in cefepime, amikacin and meropenem were effective in most cases.

CONCLUSION

There is an increasing trend of antibiotic resistance to the commonly used first line drugs. Continuous surveillance for antibiotic susceptibility is needed to ensure proper empirical therapy.

Neonatal sepsis: high antibiotic resistance of the bacterial pathogens in a neonatal intensive care unit of a tertiary care hospital

Objective:

To study the bacterial pathogens causing neonatal sepsis and their sensitivity pattern so that guidelines can be prepared for empirical antibiotic therapy.

Materials and Methods:

We conducted a prospective analysis of all the cases admitted to the neonatal intensive care unit (NICU) of a tertiary care hospital and studied the culture and sensitivity pattern of organisms isolated. The neonates who presented with signs and symptoms of septicemia, with/without pneumonia and/or meningitis were studied and a detailed record of the maturity, age at onset, sex, birth weight (weight on admission for home deliveries), symptoms and signs along with the maternal risk factors was made. The cases with suspect sepsis were screened using various screening markers. Blood culture was done in all the cases, while cerebrospinal fluid was analysed only in those indicated. Sensitivity of the isolated organism was tested by Kirby Bauer disc diffusion techniques and various drug resistance mechanisms were studied.

Result:

Out of the 190 neonates (M:F=1.22:1) admitted to the NICU, 60 (31.57%) shows blood culture positive. Ninety-five percent cases were due to early onset septicemia. Thirty one neonates had Gram negative, twenty seven had Gram positive septicemia and two had candidial infection. Seventy percent Gram-positive isolates were resistant to penicillin. Ninety percent Gram negative isolates were resistant to gentamycin and ampicillin. Carbapenem resistance mechanisms such as ESBL.

Conclusion:

There is an increasing trend of antibiotic resistance to the commonly used and available drugs. Continuous surveillance for antibiotic susceptibility should be done to look for resistance pattern.

Staphylococcus aureus- the predominant pathogen in the neonatal ICU of a tertiary care hospital in amritsar, India

BACKGROUND

An early treatment and the appropriate and the rational use of antibiotics would minimize the risk of severe morbidity and mortality in neonatal sepsis, and reduce the emergence of multi-drug resistant organisms in intensive care units. For the success of an early empiric treatment, a periodic review of the cases to assess any changing trends in the infecting organisms and their antimicrobial susceptibility is important.

AIM

To study the most commonly encountered bacterial pathogens which caused neonatal sepsis and their sensitivity patterns, so that guidelines could be prepared for a rational antibiotic therapy.

SETTING AND DESIGN

This was a retrospective study which was conducted in the Department of Microbiology and the Neonatal Intensive Care Unit (NICU) at SGRDIMSAR, Amritsar, during June 2011 to June 2012.

METHODS AND MATERIALS

Blood specimens for culture were drawn from 311 newborns who were admitted in an NICU with sepsis. The specimens were inoculated into brain heart infusion broth. Subcultures were performed on days 1, 2, 3, 5, 7 and 10. The isolates were identified by doing standard biochemical tests. The antibiotic resistance patterns of the isolates were studied by the Kirby Bauer disc diffusion technique.

RESULTS

A total of 131 organisms were isolated from the 311 blood cultures. These included Staphylococcus aureus (n=68), Coagulase Negative Staphylococcus (CoNS) (n=30), Klebsiella pneumoniae (n=10), Acinetobacter baumannii (n=9), Escherichia coli (n=05), Enterobacter cloacae (n=04), Citrobacter diversus (n=02), Pseudomonas aeruginosa (n=02) and Candida (n=01). Staphylococcus aureus was the main pathogen in both early and late-onset sepsis. On antibiotic sensitivity testing, 57.35% of the Staphylococcus aureus isolates were found to be methicillin resistant. More than 90% gram negative rods were resistant to amikacin. The resistance to the third generation cephalosporins varied between 50-55%. The resistance to ciprofloxacin was quite high; however, most of the isolates were susceptible to levofloxacin. A majority of the isolates were susceptible to piperacillin- tazobactum and imipenem.

CONCLUSION

The present study emphasized the importance of periodic surveys on the microbial flora which was encountered in particular neonatal settings to recognize the trend.

Resistant patterns of bacteria isolated from bloodstream infections at a university hospital in Delhi

Background:

The choice of antimicrobial therapy for bloodstream infections is often empirical and based on the knowledge of local antimicrobial activity profiles of the most common bacteria causing such infections.

Aims:

The present study was aimed to investigate frequency of bacterial pathogens causing septicemia and their antimicrobial resistant pattern in hospital admitted patients.

Settings and Design:

It was a prospective study, conducted at Majeedia Hospital, Hamdard University, New Delhi, India.

Material and Methods:

We examined prospectively, 168 bacterial strains isolated from 186 clinically diagnosed septicemia cases admitted at a University Hospital in New Delhi, over a period of six months from July 2009 to December 2009. Antimicrobial susceptibility was performed according to Clinical and Laboratory Standards Institute (CLSI, USA) guidelines.

Results:

The most frequently identified Gram-positive bacteria were coagulase-negative staphylococci 63.5%, Staphylococcus aureus 23.1%, enterococci 5.8% and alpha-haemolytic streptococci 5.8%. The most frequently Gram-negative bacteria identified were Acinetobacter species 31%, Salmonella typhi 24.1%, Escherichia coli 23.3% and Pseudomonas aeruginosa 13.8%. Coagulase-negative staphylococci showed maximum resistance to cefaclor 57.1% and ampicillin 46.9%. Staphylococcus aureus showed maximum resistance to amoxicillin 100% and ampicillin 91.7%. Acinetobacter species showed maximum resistance to amoxicillin 89.7%, amoxiclav 87.1% and ampicillin 85.7%. Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae showed maximum resistance to ampicillin, 46.4%, 92%, 93.8% and 100%, respectively.

Conclusions:

Gram-negative pathogens predominated in bloodstream infections. Resistance to most of the antimicrobial agents for a number of pathogens implicated in bloodstream infections, especially in Gram-negative bacteria, has reached worrisome levels and continues to increase.

Metallo-beta-lactamase Producing Pseudomonas aeruginosa in Neonatal Septicemia

Gram-negative bacilli are important agents causing neonatal sepsis. The organisms isolated are often resistant to multiple antimicrobials specially which are metallo-beta-lactamases (MβL) producers. Therefore, the present study was conducted with the objective to examine the incidence of MβL producing strains in multidrug resistant (MDR) Pseudomonas aeruginosa from cases of neonatal sepsis. Between January-December 2006, 1994 cases of neonatal sepsis were investigated. The isolates obtained were identified and tested for susceptibility to various antimicrobial agents. The multidrug resistant P. aeruginosa isolates were screened for the presence of MβL by imipenem-EDTA disc method. Five hundred and ninety three (29.73%) isolates were obtained from culture of neonates. Most frequent offender was P. aeruginosa (48.2%). There was an overall predominance of gram-negative organisms. MβL production was seen in 69.5% of imipenem-resistant P. aeruginosa isolates. MβL producing P. aeruginosa is an emerging threat in neonatal septicemia and a cause of concern for physicians treating such infections.

Analysis of ESBL- and AmpC-positive Enterobacteriaceae at the Department of Neonatology, University Hospital Olomouc

Bacterial infections are an important issue in current clinical medicine. The severity of infectious diseases has increased dramatically in recent years, which is also due to increasing numbers of resistant bacteria, including strains producing broad-spectrum beta-lactamases. The study aimed at determining the prevalence of ESBL- and AmpC-positive Enterobacteriaceae at the Department of Neonatology, University Hospital Olomouc. Enterobacteriaceae were isolated from clinical samples from infants hospitalized at the Department of Neonatology, University Hospital Olomouc over a period of 2 years. ESBL- and AmpC-positive isolates were subjected to basic genetic analysis. In the study period, a total of 1,526 isolates of the Enterobacteriaceae family were identified, including 55 (3.6%) cases of the ESBL phenotype and 17 (1.1%) AmpC-positive isolates. Genetic analysis of ESBL-positive isolates revealed a majority of CTX-M enzymes. Among AmpC beta-lactamases, the EBC, CIT, DHA, and MOX types were detected. An Escherichia coli strain was isolated with mutations in the promoter region of the ampC chromosomal gene that are associated with overproduction of the relevant enzyme.