Predominant Gram Research Articles

P-738. A Microbiological Profile of Necrotizing Fasciitis at a Tertiary Referral Hospital in a Low/Middle Income Country

Abstract Background : Necrotizing fasciitis (NF), an uncommon, fatal infection of the skin and soft tissues, carries a significant mortality risk, with rates reaching as high as 76% despite prompt surgical interventions. While polymicrobial infections were more likely to be encountered, few studies reported a monomicrobial predominance. Despite its relevance, there is a notable lack of data in the Eastern Mediterranean region. We aimed to investigate the microbiological profile among patients diagnosed with necrotizing fasciitis in a tertiary referral center in Lebanon, with a particular focus on Multidrug-resistant organisms (MDROs) and Antimicrobial Resistance (AMR), given their increasing prevalence and the challenges they pose in clinical management.Table 1:Distribution of Organisms Methods A retrospective chart review of hospitalized cases between 2011 and 2021. The study population included adult patients diagnosed with NF during this period. Data included microbiological characteristics, with focus on Multidrug-resistant organisms (MDROs).Figure 1:Yearly Trend of MDROs Among Isolated Organisms Results 41 cases of NF were identified showing a mortality rate of 37%. 46 % of cases had polymicrobial infections versus 42% monomicrobial. The predominant gram negative pathogen was E.coli in both types of infections followed by the gram positive pathogen, Enterococcus species. No difference in the type of infection was noticed in the survival group compared to a predominance of polymicrobial infection in the non-survival group. Fungi were recovered represented in 5.4% of cases and were part of a polymicrobial infection. Out of all the isolated organisms, 21.2% showed patterns of resistance (Extended Spectrum Beta Lactamase, Multidrug resistant, Vancomycin Resistant Enterococcus, and Carbapenem Resistant Enterobacteriaceae) with a yearly incremental rise. Conclusion This 10-year study emphasizes the urgency of prompt surgical intervention and tailored antibiotic treatment for NF, particularly in the context of increasing AMR and the presence of MDROs, contributing crucial regional data on NF demographics, comorbidities, and microbiology Disclosures All Authors: No reported disclosures

A multicentre prospective registry of one thousand sepsis patients admitted in Indian ICUs: (SEPSIS INDIA) study

BackgroundSepsis is a global health problem with high morbidity and mortality. Low- and middle-income countries have a higher incidence and poorer outcome with sepsis. Large epidemiological studies in sepsis using Sepsis-3 criteria, addressing the process of care and deriving predictors of mortality are scarce in India.MethodA multicentre, prospective sepsis registry was conducted using Sepsis 3 criteria of suspected or confirmed infection and SOFA score of 2 or more in 19 ICUs in India over a period of one year (August 2022–July 2023). All adult patients admitted to the Intensive Care Unit who fulfilled the Sepsis 3 criteria for sepsis and septic shock were included. Patient infected with Covid 19 were excluded. Patients demographics, severity, admission details, initial resuscitation, laboratory and microbiological data and clinical outcome were recorded. Performance improvement programs as recommended by the Surviving Sepsis guideline were noted from the participating centers. Patients were followed till discharge or death while in hospital.ResultsRegistry Data of 1172 patients with sepsis (including 500 patients with septic shock) were analysed. The average age of the study cohort was 65 years, and 61% were male. The average APACHE II and SOFA score was 21 and 6.7 respectively. The majority of patients had community-acquired infections, and lung infections were the most common source. Of all culture positive results, 65% were gram negative organism. Carbapenem-resistance was identified in 50% of the gram negative blood culture isolates. The predominant gram negative organisms were Klebsiella spp (25%), Escherechia coli (24%) and Acinetobacter Spp (11%). Tropical infections (Dengue, Malaria, Typhus) constituted minority (n = 32, 2.2%) of sepsis patients. The observed hospital mortality for the entire cohort (n = 1172) was 36.3%, for those without shock (n = 672) it was 25.6% and for those with shock (n = 500) it was 50.8%. The average length of ICU and hospital stay for the study cohort was 8.64 and 11.9 respectively. In multivariate analysis adequate source control, correct choice of empiric antibiotic and the use of intravenous thiamine were protective.ConclusionThe general demographics of the sepsis population in the Indian Sepsis Registry is comparable to Western population. The mortality of sepsis cohort was higher (36.3%) but septic shock mortality (50.8%) was comparable to Western reports. Gram negative infection was the predominant cause of sepsis with a high incidence of carbapenem resistance. Eschericia coli, Klebsiella Spp and Acinetobacter Spp were the predominant causative organism. Tropical infection constituted a minority of sepsis population with low hospital mortality. The SOFA score on admission was a comparatively better predictor of poor outcome. Sepsis secondary to nosocomial infections had the worst outcomes, while source control, correct empirical antibiotic selection, and intravenous thiamine were protective.CTRI Registration CTRI:2022/07/044516.

A Temporal Study on Incidence of Bovine Mastitis in Haryana, India

Mastitis affects dairy animal’s productivity and causes financial losses for dairy farmers in India and across the world. In this study, a total of 52,494 quarter milk samples from 14,381 bovines were screened for the primary microorganisms causing mastitis in Hisar and adjoining districts of Haryana and their antibiotic sensitivity patterns were analyzed. The cultural positivity from subclinical form of mastitis was observed as 86.32% and 87.73% from cows and buffaloes, respectively while that from clinical mastitis was 87.36% and 87.57%. The major Gram positive bacterial pathogens associated with mastitis in the entire study period were found as Staphylococcus species with an average incidence rate of 45.53% and 44.1% from cows and buffaloes, respectively. The Streptococcus species were found to be 33.76% and 29.94% of total isolates. Escherichia coli were the most predominant Gram negative bacteria isolated (17.37% and 13.85%), thereafter Klebsiella spp. (5.54% and 5.19%) from both cows and buffaloes. A significant proportion of clinical cases of mastitis were chronic in nature from both the species of bovines. The incidence of mastitis with respect to different lactation number and lactation months was found as significant. The highest incidences of mastitis was observed in the first lactation among buffaloes (20.69%), while the maximum incidences were observed in second and third lactation in cows with 16.59% and 16.99%, respectively. However, in both the species maximum occurrence of mastitis was observed during the first lactational month. The antibiotic sensitivity patterns of most of the isolates had shown higher sensitivity towards enrofloxacin and gentamicin, while the penicillin had shown least sensitivity. The knowledge regarding the mastitis causing pathogens and their sensitivity pattern in Hisar and adjoining districts of Haryana enables the veterinarians to adopt for the proper treatment protocols and dairy farmers to assure optimal health, welfare and productivity of bovines in the State, in turn reducing antimicrobial resistance.

STUDY ON EMERGENCE OF MDR PATHOGEN AND ITS MICROBIOLOGICAL STUDY

Antimicrobial resistance is now a major challenge to clinicians for treating patients.Hence, this study was undertaken to detect the incidence of multidrug-resistant (MDR),extensively drug-resistant (XDR) and pandrug-resistant (PDR) bacterial isolates in a tertiary care hospital. Aims and Objectives: This study was undertaken to detect the incidence of MDR, XDR and PDR bacterial isolates in a tertiary care hospital and to help in antibiotic policy of a hospital to guide the clinicians for empirical usage of antibiotics and prevent drug resistance. Methodology: This research study was conducted to isolate multi-drug resistant pathogen.All the clinical samples like pus, swab, urine, body fluids, medical devices, blood culture, sputum, drain etc., received for culture and sensitivity in Microbiology laboratory during Jan 2022 to December 2022 were included. They were inoculated and then incubated, and gram staining was performed. Antibiotic resistance and susceptibility were measured by the disk diffusion method according to the Clinical and Laboratory standards institute (CSLI) guidelines. Result: Out of 5501patients 2008 (37%) patients were showing culture positive during one year. The predominant gram negative isolate in our study was E.coli (19%) followed by klebsillaspp (18%), staphylococcus aureus (16%) and pseudomonas (13%) respectively. It shows that colistin was found to be more sensitive for gram negative organisms followed by aminoglycosides and carbapenem group, while resistance was observed towards fluoroquinolone, 1st and 2nd generation cephalosporine groups. &Vancomycin, Teicoplanin and Linezolide were highly active drugs against Gram positive organisms. Conclusion: The vast majority of isolated organisms in this study were gram-negative bacteria, and most were showing high antimicrobial resistance. The antibiograms should be developed and regularly updated at every ward and hospital. There is a need to bring more awareness about the proper use of antimicrobials among healthcare workers, and antimicrobial stewardship programs can help in this matter.

Susceptibility Pattern of Blood Stream Infections in Neonatal Sepsis: Striking Alarm in Era of Antibiotic Resistance

Neonatal blood stream infections are significantly associated with increased morbidity and mortality in the recent years. In this study, we aim to determine the bacteriological profile and antibiotic susceptibility pattern of culture positive neonatal sepsis in the NICU of a tertiary teaching hospital in Kolkata. This retrospective study was conducted in the Department of Microbiology of a tertiary care teaching hospital in Kolkata between August, 2020 to July, 2021. All the neonates [both inborn / out born] admitted to NICU with the clinical diagnosis of sepsis during the specified period were screened for BSI. The blood was cultured in BACTAlert and analysed by VITEK 2. Out of 200 neonates with sepsis, 30 had culture positive sepsis of which 60% were Gram positive, rest were Gram negative. Staphylococcus aureus and Coagulase negative Staphylococcus (CoNS) were predominant (35.2%), Klebsiella was the predominant Gram negative organisms. Babies with birth weight ≤ 2 kg and gestational age 33 to 37 weeks were affected. Mortality was seen in 36.3% babies. Significant proportion of multidrug resistant isolates posed a great threat to neonatal survival. Hence modification of therapy based on anti-microbial surveillance pattern of the Institution with implementation of proper escalation and de-escalation of therapy is warranted. Keywords: antibiotic resistance, blood stream infections, culture positive sepsis

BACTEREMIA: THE CULPRIT FOR THE MORBIDITY & MORTALITY IN POST COVID PATIENTS

Background: Bloodstream infections are an emerging cause of signicant morbidity and mortality in critically ill COVID-19 patients. The present study was designed to evaluate the incidence of BSI and to identify its causative agents in critically ill Covid positive patients to provide targeted therapy to improve the outcome in such patients. This retrospective observational study was conducted at Tejas Microdiagnostics during 30Material and method: April 2021 to 30 June 2021. A total of 126 Covid positive patients requiring admission in SRN Hospital, Prayagraj were included. Blood specimen collected in FA and FAN bottles were sent for culture and antibiogram to Tejas Microdiagnostics within eight hours of admission. Blood culture of 89 (70%) patients was positive while 37 (30%) patients did not show any growth.Results: Bacterial growth was identied in 65 (73.04%) cases while fungi were isolated in 24 (26.96%) cases. Acinatobacter was identied in single patient. Klebsiella pneumoneae (19.23%) and Staphylococcus aureus (15.38%) were the predominant gram negative and gram positive aerobes while Fusobacterium (46.15%) and Peptococcus (15.38%) was gram negative and gram positive anaerobes. Mortality was observed in 21% cases. Our study emphasizes that blood stream infectionsConclusion: appeared to be the signicant cause of morbidity and mortality in Covid positive patients. The reason of infections can be the wide spread use of empirical antibiotics and steroids which may increased the risk of antibiotic drug resistance and treatment failure. Therefore to reduce morbidity and mortality we have to ensure rapid Isolation and species identication in such patients.

POS-566 CATHETER RELATED BLOODSTREAM INFECTION (CRBSI) IN A MIDDLE-EASTERN COHORT OF HEMODIALYSIS PATIENTS: AN ANALYSIS OF 5 YEARS OF FOLLOW UP DATA

Bloodstream infections (BSI) are the second commonest cause of morbidity and mortality in end stage renal failure (ESRF) patients. Dialysis catheters are believed to be the most common contributors to BSI in this cohort. Therefore, patients who are receiving hemodialysis via long term central venous catheters (CVC) are at significantly high risk of CRBSI and its associated morbidity and mortality. Although there are several studies on CRBSI from different cohorts around the world, long-term follow up data are scarce particularly from middle eastern cohorts. We aim to fill this knowledge gap as well as to develop an antibiogram and antibiotic stewardship for this unique cohort of patients. This is a single center retrospective longitudinal study of a middle eastern cohort receiving three times a week regular hemodialysis via permanent CVC in a large out-patient setting. We analyzed all the data from December 2015 to November 2020. Data on incidents of CRBSI, etiology, antimicrobial susceptibility, CRBSI risk factors, and comorbidities were collected. For the sake of our study, we defined CRBSI with the isolation of the same microorganism from the CVC and peripheral blood culture without any other apparent source. The incidence of CRBSI was expressed as incidence per 1000 catheter days. A total of 39 incidents of CRBSI were identified during these 5 years study period. Of the reported cases, 94% grew a single organism while 6% grew polymicrobial. Of the multitude of organisms isolated, 39% were gram positives while the rest were gram negatives. Staphylococcus aureus and enterococcus were predominant gram positives while pseudomonas and klebsiella were the predominant gram negatives. No case of MRSA or fungi were isolated. The distribution of organisms is illustrated in the bar chart below. Interestingly only 70% of cases presented with the typical triad of fever, rigors, and exit site exudates, while around 20% presented with only hypotension. 10% of the cases were completely asymptomatic and were only incidental findings. The incidence of CRBSI per 1000 catheter days was calculated for every month and as illustrated by the graph below, the CRBSI rates seem quite variable throughout this study period. However, interestingly, since the beginning of the COVID19 pandemic outbreak, the CRBSI rates are conspicuously low. This might be explainable by enhanced focus on hand hygiene by both the staff and the patients themselves during this pandemic. CRBSI incidences were higher among patients with longer duration of catheter use, previous bacteremia, old age, diabetes mellitus, and recent hospitalization.View Large Image Figure ViewerDownload Hi-res image Download (PPT) The incidence of CRBSI reported from our center seems to be comparable to other international centers around the world. The causative microorganisms and their antibiotic susceptibilities also seem to be in concordance with the rest of the world despite variations in geography, climate, and ethnicity. We conclude, that irrespective of the differences in the geographical location and study cohorts, strict adherence and attention to hand hygiene and infection control practices by both the staff and the patients are the keys to keeping CRBSI low.

The Most Predominant Gram Negative Bacteria in a Public Hospital

Aim: The aim of this study was to explore the occurrence of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii bacteria in a hospital in Al-Kharj.
 Methodology: The study included the review of antibiogram results to find the number and percentage of these bacteria in 4 years, 2015-2018.
 Results: The total number of bacterial cultures in the 4 years was 3327. Most of these cultures were for gram negative bacteria (81.06%). Regarding gram negative bacteria in the 4 years, the most common was Escherichia coli (represents 19.30% of the total bacteria and 23.80% of gram negative bacteria).
 Conclusion: It can be concluded that the most prevalent gram negative bacteria were Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia. It is important to conduct more researches to know the prevalence of these bacteria, to know their resistance rate to help health care providers to prescribe and dispense antibiotics wisely.

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.

Comparative Bacteriocidal Effect of Utazi (Gongronema Latifolium) and Onugbu (Vernonia Amygdalina) on Gram Negative Bacteria Isolated From Clinical Specimens at Specialist Hospital Owerri, Nigeria

The lowered immunity of patients with chronic kidney diseases and the increased bacterial resistance to a control antibiotic have given rise to the need to research and offer reliable evidences for the therapeutic values of the leafy vegetables like Vernonia amygdalina (Bitter leaf) and Gongronema latifolium (Utazi) in treating urinary tract infections caused by Gram negative bacteria. One hundred and twenty-seven (127) midstream urine samples were aseptically collected from patients suspected to develop renal diseases who attend the Specialist Hospital, Owerri into sterile, screw-capped universal containers and were inoculated onto CLED, EMB, Blood agar and MacConkey agar plates. These plates were then incubated at 37°C for 24 hours to obtain pure colonies. Out of the one hundred and twenty-seven (127) urine samples, forty-three (33.86%) samples yielded no significant growth whereas eighty-four (66.14%) yielded significant bacterial growth. The predominant Gram negative isolate from the samples was Escherichia coli 35(41.67%), while the least isolated Gram negative organism was Proteus mirabilis9(10.71%). Other Gram negative isolates include Klebsiella pneumoniae 24(28.57%) and Pseudomonas aeruginosa 16(19.05%). Among the Gram negative isolates, Klebsiella pneumoniae had the highest mean zone of inhibition; (8.28), with Escherichia coli having the least mean zone of inhibition; (4.45). Pseudomonas aeruginosa and Proteus mirabilis; (6.75), respectively. Ciprofloxacin which was the control antibiotic had statistical significant difference (P<0.05) on the Gram negative isolates when compared with the aqueous and ethanolic extracts of the plants. Pseudomonas aeruginosa and Proteus mirabilis were completely resistant to the antimicrobial activity of Vernonia amygdalina aqueous extract. At 50mg/mL, Klebsiella pneumoniae was found to be resistant while at 75-150 mg/mL concentrations, an insignificant mean zone of inhibition was noted. Generally, the ethanolic extracts sho

Antibacterial screening studies of electrospun Polycaprolactone nano fibrous mat containing Clerodendrum phlomidis leaves extract

We report the design of electrospun poly caprolactone (PCL) nano fibrous mat containing ethyl acetate extract of medicinal plant Clerodendrum phlomidis L.F (CP). Non polar solvent extract of Clerodendrum phlomidis leaf analyzed for their phytochemical components and chemical identification by GC–MS analysis. More than 40 phyto constituents were identified and the major components found to be terpenoids, flavonoids, phytol, hexadecanoic acid and palmitic acid. SEM images revealed there was a substantial decrease in PCL fiber diameter from 400 to 300 nm upon CP addition. HRTEM analysis corroborates well with the SEM results obtained. X-ray diffraction (XRD), UV–visible spectroscopy (UV–vis), and Fourier transform infrared (FTIR) spectroscopy confirmed the CP incorporation into the matrix. Water contact angle measurement showed with the addition of CP, there was an increase in wettability of the PCL fibers without affecting their mechanical properties. TGA studies showed the as spun mats were thermally stable. Antibacterial studies were investigated against the predominant pathogenic gram positive and gram negative bacteria: Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella Typhi and Escherichia coli. The releasing studies for a period of 60 h was conducted and results showed that initial burst release within first 8 h and slow release was continued over a prolonged period of time. Overall results proved that the prepared mats can find its potential application in the field of antimicrobial wound dressings and antioxidant activity.

Prevalence of Gram Negative Bacteria Isolated from Patients with Burn Infection and their Antimicrobial Susceptibility Patterns in Kirkuk City, Iraq

Burn injury compromises the skin barrier and enables bacterial infection, hence delaying burn wound healing. This study aimed to determine the microbial profile of burn wounds, and resistance patterns of microbes with respect to the source of the injured patient's wound. From 130 wound swab samples were collected from burn patients at Azadi Teaching Hospital, Kirkuk/Iraq. Sterile swabs moistened with sterile saline were used to swab burn wounds. The swabs were plated on blood agar and MacConkey agar for 24 hrs at37°C. Biochemical tests were carried out on the representative isolate on each plate, and antibacterial sensitivity pattern was determined using the Kirby-Bauer disc diffusion method. The study revealed that the main source of burns was gas flames (60%) and scalds (29.23%). Out of the 130 samples analysed, (72.3%) were culture positive and 27.7% were culture negative for bacteria. The predominant gram negative bacteria isolated were, Pseudomonas aeruginosa 40(42.5%) followed by Klebsiella pneumoniae 23 (24.46%), Enterobacter cloacae 21 (22.34%) and Escherichia coli 10(10.63%) were the least frequently isolated bacteria. These isolates showed high resistance towards Beta lactam antibiotics and showed varying resistance levels towards non bata lactam antibiotics (Ciprofloxacin Amikacin and Gentamicin). Resistant gram negative bacteria are the most common isolates associated with burn wounds. Hence a careful selection of antibiotics to control the wound infection is required for proper management of burn wounds in order to help reduce morbidity and mortality.

Early Bacterial Cultures from Open Fractures - Differences Before and After Debridement

Background: The pattern of organisms found in open fractures is important in the selection of antibiotics for prophylaxis and empirical treatment. So far, there is paucity of data on local patterns of bacteria contaminating and infecting open fractures and their antibiotic susceptibility profile. Objective: To describe the pattern and antibiotic susceptibility of bacterial isolates obtained within 24 hours of injury from open fractures and to compare these to bacterial isolates from fractures that subsequently develop infection. Methods: A prospective study of 98 patients with open fractures seen at Kenyatta National Hospital (KNH) within 24 hours of injury between November 2015 and March 2016 was conducted. Swabs for culture and sensitivity were taken from the wounds and antibiotics initiated.Surgical debridement was subsequently carried out witha 14 day follow up for wound infection. Wounds thatbecame infected were sampled for cultures And sensitivity. Results: Fifty-one (52.2%) pre debridement wound samples had positive cultures. Staphylococcus aureus and (Coagulase Negative) CON Staphylococci were the predominant gram positive isolates. At 14 days’ follow-up, the infection rate was58.9 %. The predominant gram positive isolate was Staphylococcus aureus. Only 5.7% of the pre-debridement isolates were similar to the post debridement isolates. Conclusions: The contaminating organisms are not similar to the organisms isolated from injuries that later develop infection.Key words: Open fracture, Antibiotics, Infection, Bacterial cultures.

AmpC and extended spectrum beta-lactamases production among urinary isolates from a tertiary care hospital in Lalitpur, Nepal

BackgroundProduction of AmpC and extended spectrum beta-lactamases among urinary isolates has created a serious problem to the successful management of the urinary tract infection. The main purpose of this study was to determine the rates of the extended spectrum beta-lactamase (ESBL) production and AmpC beta-lactamase (ABL) production among urinary isolates.ResultsAmong total 564 urinary isolates, 514 (91.1%) were gram negative bacilli and 50 (8.9%) were gram positive cocci. E. coli (76.1%) was the most common bacteria isolated. Staphylococcus aureus (6.7%) was the predominant gram positive bacteria isolated. 35 (6.8%) of the 514 gram negative bacilli were ESBL producers. Similarly, 14 (2.7%) of the gram negative bacilli were ABL producers. Only one isolate was ESBL and ABL co-producer. Highest rate of susceptibility of gram negative bacteria was seen toward amikacin (97.3%) followed by imipenem (94.4%). Similarly, highest rate of susceptibility among gram positive cocci was seen toward vancomycin (100%) followed by amikacin (93.5%).ConclusionsLow rates of AmpC and extended spectrum beta-lactamases production in comparison to other previous studies were reported. On the basis of the antimicrobial susceptibility patterns of the bacteria we reported in our study, amikacin, imipenem and nitrofurantoin can be used for the preliminary treatment of urinary tract infections caused by gram negative bacteria and vancomycin and amikacin for treatment of urinary tract infections caused by gram positive bacteria.

Clinical features and bacteriological profile of late onset sepsis

Background: Neonatal sepsis is one of the major causes of morbidity and mortality in the neonatal period. Late onset sepsis (LOS) is associated with community environment or postnatal exposure to hospital environment. It's incidence is rising due to greater survival of preterm neonates and very low birth weight babies. The bacterial isolates of neonatal sepsis especially that in LOS are changing. An understanding of the changing epidemiology of neonatal LOS will help to reduce the associated mortality and morbidity. The objective was to study the clinical symptoms and signs of late onset sepsis, to study the bacteriological profile of LOS.Methods: A prospective observational study. All neonates presenting with signs and symptoms of sepsis after 72 hours of life up to day 28 were included. Babies with birth asphyxia and congenital anomalies were excluded from the study.Results: A total of 120 newborns with LOS were included in the study. Of this 42.5% had blood culture positive sepsis. Lethargy, refusal of feeds and apnoea were seen in 61.66%, 55.0% and 34.17% of babies respectively. Klebsiella (25.49%), Staphylococcus aureus (23.53%) and coagulase negative Staphylococcus (21.57%) were the predominant organisms isolated in LOS.Conclusions: Prompt diagnosis of neonatal sepsis is a challenge. The incidence of LOS in neonates is rising. Klebsiella is the most common gram negative organism; Staphylococcus aureus and CONS are the predominant gram positive organisms. CONS is emerging as an important causative organism in LOS.

Factors infleuncing neonatal septicaemia in Maiduguri, north-eastern Nigeria

BACKGROUND: Neonatal septicaemia is a leading cause of morbidity and mortality worldwide, especially in the tropics. The risk factors vary, and the clinical features of neonatal septicaemia may be vague and nonspecific, therefore a high index of suspicion is vital to early diagnosis and treatment. The aetiological agents and their antibiotic sensitivity pattern have continued to change (in the same centre over time), hence the need to have undertaken this study. AIMS AND OBJECTIVES: The primary objective of the study was to determine the risk factors influencing the aetiology of neonatal septicaemia at the University of Maiduguri Teaching Hospital. PATIENTS AND METHODS: The study was prospective and all the newborn that had clinical diagnosis of septicaemia were consecutively enrolled and admitted to the Special Care Baby Unit of the Department of Paediatrics of University of Maiduguri Teaching Hospital (UMTH). The patients were appropriately investigated including blood cultures, cerebrospinal fluid cultures and urine culture among others. RESULTS: One hundred and ten neonates were studied, of these 46(42.0%) had positive blood culture, while 64 (58.0%) were blood culture negative. Eighteen (39.1%) of the septicaemic neonates were inborn, while 28 (60.9%) were out born. The incidence of neonatal septicaemia among babies delivered at UMTH was 5.9/1000 live births and the male to female ratio among septicaemic neonates was 1.9:1. The common risk factors for NNS were prolonged rupture of membrane (PROM), prematurity and low socioeconomic status of parents among others. Fever was the commonest clinical feature at presentation (87%), others include: poor feeding (64 %), excessive crying (33%), tachypnoea, hepatomegaly were some of the common examination findings. Staphylococcus aureus 16(69.6%) and S treptococcus pyogenes 5(21.8%) were the predominant Gram positive organisms isolated while Escherichia coli 9(39.1%) and Klebsiella Pneumoniae 7(30.4%) were the predominant Gram negative organisms isolated. CONCLUSION: Mortality was high in infection associated with Gram negative organisms and in the presence of conditions/complications like urinary tract infections, tetanus and meningiti

Type VI secretion systems of human gut Bacteroidales segregate into three genetic architectures, two of which are contained on mobile genetic elements.

BackgroundType VI secretion systems (T6SSs) are contact-dependent antagonistic systems employed by Gram negative bacteria to intoxicate other bacteria or eukaryotic cells. T6SSs were recently discovered in a few Bacteroidetes strains, thereby extending the presence of these systems beyond Proteobacteria. The present study was designed to analyze in a global nature the diversity, abundance, and properties of T6SSs in the Bacteroidales, the most predominant Gram negative bacterial order of the human gut.ResultsBy performing extensive bioinformatics analyses and creating hidden Markov models for Bacteroidales Tss proteins, we identified 130 T6SS loci in 205 human gut Bacteroidales genomes. Of the 13 core T6SS proteins of Proteobacteria, human gut Bacteroidales T6SS loci encode orthologs of nine, and an additional five other core proteins not present in Proteobacterial T6SSs. The Bacteroidales T6SS loci segregate into three distinct genetic architectures with extensive DNA identity between loci of a given genetic architecture. We found that divergent DNA regions of a genetic architecture encode numerous types of effector and immunity proteins and likely include new classes of these proteins. TheT6SS loci of genetic architecture 1 are contained on highly similar integrative conjugative elements (ICEs), as are the T6SS loci of genetic architecture 2, whereas the T6SS loci of genetic architecture 3 are not and are confined to Bacteroides fragilis. Using collections of co-resident Bacteroidales strains from human subjects, we provide evidence for the transfer of genetic architecture 1 T6SS loci among co-resident Bacteroidales species in the human gut. However, we also found that established ecosystems can harbor strains with distinct T6SS of all genetic architectures.ConclusionsThis is the first study to comprehensively analyze of the presence and diversity of T6SS loci within an order of bacteria and to analyze T6SSs of bacteria from a natural community. These studies demonstrate that more than half of our gut Bacteroidales, equivalent to about ¼ of the bacteria of this ecosystem, encode T6SSs. The data reveal several novel properties of these systems and suggest that antagonism between or distributed defense among these abundant intestinal bacteria may be common in established human gut communities.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-2377-z) contains supplementary material, which is available to authorized users.

Intestinal immune cell quantification and gram type classification of the adherent microbiota in conventionally and artificially reared, normal and low birth weight piglets

To be able to raise larger litters, the influences of alternative rearing strategies on piglets are currently assessed. This study compared the predominant Gram type of the adherent intestinal microbiota between conventionally and artificially reared piglets and quantified their major mucosal immune cell populations. In addition, the potential influence of the piglets' birth weights was examined. To this purpose, 40 neonatal piglets consisting of 20 normal birth weight (NBW) and 20 low birth weight (LBW) piglets suckled the sow for three days after which 20 piglets (10 NBW and 10 LBW) continued to suckle the sow and 20 piglets (10 NBW and 10 LBW) were transferred to brooders and raised on milk formula. At the age of 10 or 28 days, five piglets of each group (birth weight×rearing strategy) were euthanized and the jejunum was sampled. The presence of adherent Gram+ and Gram− bacteria was scored and the volume densities of CD8+ cells, CD4+ cells and CD172a+ myloid cells were determined. Irrespective of birth weight, sow-fed piglets possessed a predominant Gram+ microbiome at 10 days of age, whereas formula-fed animals had more Gram- microbiota. With increasing age, however, Gram+ microbiota took the upper hand in these animals. The volume densities of CD8+ and CD4+ cells rose with increasing age and were consistently lower in LBW piglets. Both rearing strategies had a similar influence on the volume densities of these cell populations. In contrast, the volume densities of CD172a+ myloid cells did not differ significantly between the birth weight, rearing strategy and age groups. Three observations allow to conclude that artificial rearing could be a valuable alternative for suckling the sow. First, within each birth weight category, the mean weight of the 28-day-old piglets was similar for both rearing groups. Secondly, the effect of milk formula on the composition of the intestinal microbiome was only temporary since formula-fed piglets restored the more beneficial Gram+ microbiome by the end of the artificial rearing period. Finally, artificial rearing did not influence, either positively or negatively, the volume densities of CD8+, CD4+ and CD172a+ immune cells when compared to conventional rearing.

Identification of the bacterial isolates in neonatal septicaemia and their antimicrobial susceptibility in a tertiary care hospital in Uttarakhand, India: a retrospective study

Background: Neonatal sepsis refers to systemic bacterial infection documented by positive blood culture in the first four weeks of life and is one of the four leading causes of neonatal mortality and morbidity in India. This study was a retrospective study to identify the bacterial isolates in neonatal septicaemia and their antimicrobial susceptibility in a tertiary care hospital in Uttarakhand, India from January 2013 to June 2015. Methods: Blood culture in newborns with clinical sign of septicaemia was retrospectively studied. Antimicrobial susceptibility testing was performed by Kirbuay -bauer disc diffusion susceptibility method in accordance to clinical laboratory standard institute guidelines (CLSI) . Results: 10.3% (124 /1200) cases of septicaemia could be confirmed by blood culture. Of these Gram negative could be isolated in (62%) of cases and (38%) were of gram positive isolates. Kliebsiella was the predominant pathogen (42.8%) among the gram negative pathogens followed by E coli (18.1%). CONS (57.4%) was the predominant gram positive pathogen. Of the Gram positives isolates 6% were methicillin resistant S.aureus (MRSA). Polymyxin (77.8%) and tigecycline (72%) were most effective drugs against gram negative isolates were as gram positive organisms showed maximum sensitivity to vancomycin (90%) and linezolid (87%). Conclusions: This study highlights the growing resistance to commonly used antibiotics; ampicillin, penicillin, ceftriaxone and ceftazidime and also highlights the importance of kleibsiella and Staphylococcus aureus as principal organism responsible for neonatal sepsis in tertiary care settings.

The waaL gene mutation compromised the inhabitation of Enterobacter sp. Ag1 in the mosquito gut environment.

BackgroundThe mosquito gut harbors a variety of bacteria that are dynamically associated with mosquitoes in various contexts. However, little is known about bacterial factors that affect bacterial inhabitation in the gut microbial community. Enterobacter sp. Ag1 is a predominant Gram negative bacterium in the mosquito midgut.MethodsIn a mutant library that was generated using transposon Tn5-mediated mutagenesis, a mutant was identified, in which the gene waaL was disrupted by the Tn5 insertion. The waaL encodes O antigen ligase, which is required for the attachment of O antigen to the outer core oligosaccharide of the lipopolysaccharide (LPS).ResultsThe waaL− mutation caused the O antigen repeat missing in the LPS. The normal LPS structure was restored when the mutant was complemented with a plasmid containing waaL gene. The waaL− mutation did not affect bacterial proliferation in LB culture, the mutant cells grew at a rate the same as the wildtype (wt) cells. However, when waaL− strain were co-cultured with the wt strain or complemented strain, the mutant cells proliferated with a slower rate, indicating that the mutants were less competitive than wt cells in a community setting. Similarly, in a co-feeding assay, when fluorescently tagged wt strain and waaL− strain were orally co-introduced into the gut of Anopheles stephensi mosquitoes, the mutant cells were less prevalent in both sugar-fed and blood-fed guts. The data suggest that the mutation compromised the bacterial inhabitation in the gut community. Besides, the mutant was more sensitive to oxidative stress, demonstrated by lower survival rate upon exposure to 20 mM H2O2.ConclusionLack of the O antigen structure in LPS of Enterobacter compromised the effective growth in co-culture and co-feeding assays. In addition, O-antigen was involved in protection against oxidative stress. The findings suggest that intact LPS is crucial for the bacteria to steadily stay in the gut microbial community.