Burns infection profile of Singapore:prevalence of multidrug-resistant Acinetobacter baumannii and the role of blood cultures

Background:With various changes implemented such as perioperative antibiotics for tangential excision,this retrospective study reviews the infection profile of burn patients at Singapore's only centralized burns unit.Worldwide,the appearance of multidrug-resistant(MDR)strains of Acinetobacter baumanni(A.baumanni)continues to worsen patient outcomes.This study also surveys the role of blood cultures in burns at our unit.Methods:Four hundred fifty-two burn patients admitted to the unit between 2011 and 2013,and with cultures performed,were included in the study.The yields of various cultures were evaluated and 2684 samples were amassed,of which 984(36.7%)were positive.Patient variables for predictors of MDR A.baumanni infection acquisition and bacteremia were evaluated through multivariate analyses.Results:Pseuodomonas aeruginosa(P.aeruginosa)(67 patients)was the most common organism in those with total body surface area(TBSA)burn<20%while MDR A.baumanni(39 patients)was most prevalent in those with TBSA burn≥20%.We found a yield of 1.1%positive blood cultures for TBSA burn<20%and a yield of 18.6%positive cultures in TBSA burn≥20%.The median time between surgery and bacteremia was 6.5 days(range-18 to 68 days,interquartile range 4.5);2.9 and 8.8%of bacteremic episodes occurred within 24 and 48 h,respectively.This is a decrease from a predeceasing study(45.3%for 24 h and 60%for 48 h).Multivariate analysis revealed that length of hospital stay and TBSA burn≥20%were predictors of MDR A.baumanni infection and positive blood cultures.Conclusions:MDR A.baumanni infection burdens patient management,especially in those with TBSA burn≥20%and longer hospital stay.Prophylactic antibiotics may reduce perioperative bacteremia,but their role in MDR infections needs to be evaluated.The role of blood cultures in TBSA burn<20%needs reconsideration.

Distribution and Drug Resistance Analysis of 2287 Strains of Pathogenic Bacteria in Children’s Blood Culture

Background: Bloodstream infection is a serious infectious disease. In recent years, the drug resistance of pathogenic bacteria to commonly used anti-infective drugs has been widely concerned, which also makes the treatment of bloodstream infection face severe challenges. Objective: To explore the distribution characteristics of blood culture-positive pathogens and the resistance to antibacterial drugs, so as to provide clinicians with accurate laboratory evidence, so as to guide clinicians to rationally apply antibiotics, improve clinical treatment effects, and reduce the emergence of drug-resistant strains. Methods: From January 2019 to June 2022, 2287 positive blood culture specimens of patients in Guangzhou Women and Children’s Medical Center were retrospectively analyzed, and the proportion of different pathogenic bacteria, the distribution of pathogenic bacteria in different departments, and the multi-drug resistance of different pathogenic bacteria were counted. Results: Among the 2287 blood culture positive samples, 1560 strains (68.20%) of gram-positive bacteria and 727 strains (31.80%) of gram-negative bacteria were strained. The top three departments in the distribution of pathogenic bacteria were pediatric intensive care unit (600 strains), pediatric internal medicine (514 strains), and pediatric emergency comprehensive ward (400 strains). The pathogens with high detection rates were: Staphylococcus epidermidis (24.09%), Staphylococcus humans (23.74%), Escherichia coli (13.21%) and Klebsiella pneumoniae (8.71%). The pathogens with high multi-drug resistance rates were: Streptococcus pneumoniae (93%), Staphylococcus epidermidis (83.76%), Enterobacter cloacae (75.61%) and Staphylococcus humans (62.43%). Conclusion: In our hospital, gram-positive bacteria were the main pathogenic bacteria in the blood culture of children patients. The children’s intensive care unit was the department with the largest distribution of pathogenic bacteria, and the multiple drug resistance rate of Streptococcus pneumoniae was the highest.

Trends in Bacterial Blood Culture Isolates and Resistance in Children in Two Microbiologic Eras from a Tertiary Health Facility in North East Nigeria

Introduction: Antimicrobial Resistance surveillance is predicated on blood culture as a priority clinical specimen in especially resource limited settings. Establishing trends in blood stream infections and resistance patterns can inform institutional and national policy on antimicrobial stewardship, surveillance, infection prevention and control. Methodology: Blood Culture isolates in children (0 - 18 years) by conventional method from 2008-2012 and Bactec Automated culture system from 2015-2020 were retrieved. Information analyzed included age, sex, month, and year and culture growth/identity of microorganisms and their sensitivity/resistance patterns. Clinical and Laboratory Standards Institute (CLSI) guideline for antibiotic susceptibility testing was used. Results: 20,540 children were admitted: 8964 (44.6%) and 11,630 (55.4%) in the Manual and Bactec blood culture era respectively. Blood cultures were done in 5271 in the manual culture era and 1077 in the Bactec culture era;of these cultures, 514 (9.7%) and 461 (42.8%) were positive for isolates in the respective era (p = 0.01). There were no statistically significant differences in trend between positive and negative blood cultures in males and females. Newborns, followed by children 1 - 5 years had more blood culture performed on them than other age categories. In general, there is no significant relationship in blood culture outcomes between the age categories and sex of the patients. The isolation of Staph aureus, Citrobacter and Alkaligenes increased two-fold with Bactec automated system. Resistance to the quinolones and the penicillin was high. Resistance trend to Genticin, an aminoglycoside was less than 40%. Resistance to Ceftazidime was high. Conclusion: Antimicrobial resistance surveillance is critical to reduce AMR related morbidity and mortality.

Bacterial Blood Isolates in Children: Conventional vs. Bactec Automated Blood Culture System in a Tertiary Health Centre in Gombe, North East Nigeria

Background/Aim: Blood culture is critical in the diagnosis and treatment of blood stream infections (BSIs) especially in children. BSIs are among the most common cause of morbidity/mortality and blood culture has remained the gold standard for diagnosis. We sought to compare Blood Culture Isolates (BCI) from conventional and Bactec automated blood culture system (ABCS) among paediatric patients at the Federal Teaching Hospital Gombe (FTHG) Nigeria. Methods: BCI in children (0 - 18 years) by conventional method from 2008-2012 and Bactec Automated culture system from 2015-2020 were retrieved from the clinical microbiology laboratory register. Information analyzed included, age, sex, month, and year and blood culture isolates. Results: There were 5276 (56.9% males, 43.1% females) and 1169 (54% males, 46% females) Blood Culture Isolates by CM and ABCS respectively. Overall positive culture isolates were 9.7% (515/5276) in CM and 45.9% (536/1169) in ABCS (p = 0.01). Positivity rate in newborn was 13.3% (282/2114) by CM and 40.9% (219/263) by ABCS p = 0.01;under-5 was 10.5% (448/4253) vs. 37% (359/873) (p = 0.01);Gram positive 32.6% (172) vs. 65% (759) (p = 0.01;Gram negative 55% (2910) vs. 34% (397) (p = 0.01). Staph aureus 22% (114/515) by CM vs. 61.9% (332/536)) by ABCS (p = 0.01);Klebsiella 24.9% (128/515) by CM vs. 7.5% (40/536) p = 0.01) in ABCS, E. coli 8.9% (46/515) vs. 2.1% (11/536) p = 0.01;Proteus vs. 1.1% (6/515) by ABCS, Pseudomonas 3.3% (17/515) vs. 5.6% (30/536) p = 0.05, Alkaligenes 1% (5/515) vs. 8.2% (44/536) p = 0.01 and Citrobacter 1% (5/515) vs. 8.4% (45/536) p = 0.01. Conclusion: Blood culture yield was five times higher with Bactec compared with Conventional method.

Transitioning to Automated Microbiologic Era: Blood Culture Isolates in Children and Adults in Federal Teaching Hospital in Gombe, North East Nigeria 2016-2020

Introduction: Automated blood culture systems for incubation and growth monitoring have become the standard in high-income countries (HICs), but are still relatively expensive and not universally available for implementation in most low- and middle-income countries (LMIC). We aimed to report blood culture isolates using Automated technique in children and adults admitted into the Federal Teaching Hospital Gombe from 2016 to 2020. Materials and Methods: Blood Culture Isolates in children (0 - 18 years) and adults (>19 yrs) by Bactec 9050 Automated culture system from 2016-2020 were retrieved from the medical and laboratory register. Information analyzed included, age, sex, month, and year and culture growth and reported antibiotic sensitivity. A Bactec Blood culture tests is $20 in this facility. In Nigeria, the minimum monthly wage is $70 (Official currency exchange rate is N423/US Dollar). Results: Of the 1713 blood cultures performed, children 0 - 18 years were 1322 (77.2%) and adult (19 years above) (22.8%). Overall positivity was 733 (42.2%) with males 385 (52.5%). Of the 1322 Blood cultures (BC) in children 615 (46.5%) were positive for isolates and adults 118 (30.2)%. Blood culture positivity decreased with increasing age with newborns 251 (34.5%) and adults > 65 years 18 (2.5%). Staphylococcus aureus constituted 61.3% of all isolates and was the leading isolates in all age groups;Alkaligenes (9.1%);Citrobacter 8.1%, Klebsiella 6.7%;Pseudomonas 6.1%;E. coli 2.7%;Enterococcus 2%;Proteus 1%. Of the Antimicrobial resistance priority isolates E. coli susceptibility ranged from 71% to Gentamycin and 100% to Cefixime;Klebsiella from 25% sensitivity to Amikacin to 78% each to chloramphenicol and ciprofloxacin;Salmonella was 100% sensitive to chloramphenicol, ciprofloxacin and cefuroxime. Klebsiella was 100% sensitive to Cefoxitin;Proteus sensitivity ranged from 35% to ampicillin and 100% to ciprofloxacin and cefuroxime. Staph aureus sensitivity was 35% to cefoxitin, 70% to amoxicillin/clavulanate and 70% to cefuroxime. Conclusion: Blood culture yield by Automated method was high. Staph aureus was the predominant pathogen and bacterial yield reduced with increasing age. Antibiotic sensitivity was variably reduced against gram negative bacteria.

The Slippery Slope of Sepsis

Mortality, morbidity, early recognition, and treatment of sepsis remain a diagnostic dilemma for clinicians, in addition, the timely diagnosis of sepsis represents an ongoing clinical challenge. This review looks at the challenges of early recognition, the scope of the problem, the immunologic basis of the sepsis cascade, new frontiers related to interventions, and the role of antibiotics in an era of antimicrobial resistance. In Figure 1, once a patient is on the slippery slope of sepsis, the ability to reverse the momentum is challenging;hoping antibiotics, fluid resuscitation, vasopressors may buy time for the immunologic cascade to equilibrate to its homeostatic balance. While the development of septic shock is much more complex than pathogen proliferation, our understanding of the pathogenesis and ability to therapeutically intervene is in its infancy. Patients with sepsis frequently present for urgent medical care with undifferentiated infection and nonspecific symptoms. As 80% of patients with sepsis are initially treated in an Emergency Department, the burden of early recognition and intervention falls squarely on the shoulders of Emergency Department Clinicians. [1] This is an entity that occurs in all age groups, without regard to race, geography, or health status. Survival and mortality related to this clinical entity are poorly understood. Our understanding of sepsis needs to expand beyond the downstream effects and collateral damage of multiorgan dysfunction and failure. Immunologically, the antigenic triggers, be it invasive infection, severe injury, and systemic inflammation without concomitant infection, elicit similar pattern recognition receptors and innate host responses. If you are lucky enough to have survived an acute episode of sepsis, patients with sepsis often develop new adverse sequelae after treatment, a concept called persistent critical illness or post sepsis syndrome, characterized by long-term disability, and worsening chronic health conditions requiring re-hospitalization. [2]

Bacteremia in Subjects with Sickle Cell Disease: High Rate of Gram-Negative Isolates in the West African Context!

Background: Sickle cell disease is one of the most common monogenic diseases in the world, affecting approximately 70 million people, 80% in sub-Saharan Africa and 1 in 10 in Senegal. Sickle cell anemia causes functional asplenia (associated with repeated thrombosis of splenic vessels), resulting in increased susceptibility to infection. However, several studies have reported differences in the spectrum of bacterial infections in malaria-endemic areas. Therefore, we proposed to conduct a study to determine the rate of positive blood cultures and the bacteriological spectrum in sickle cell patients. Materials and Method: This is a descriptive cross-sectional study of blood culture samples from patients who received a request for hemoglobin electrophoresis as part of their treatment at the Principal’s hospital in Dakar. The study took place from January 2008 to December 2021. For each patient, we collect demographic information, including age, gender, and the service from which the analysis request originated. Data were collected in the laboratory’s computer system and entered into Microsoft Excel (2007). Statistical analyzes were performed using Epi-Info 7 software. Results: Our study included 1419 patients. The most common types of hemoglobin profiles were: normal profile (n = 1025), AS profile (n = 283), SS profile (n = 104), SC profile (n = 7). This corresponds to the proportions of 72%, 20%, 0.5% and 7.5% for the profiles Normal, AS, SC and SS. The male proportion was 61.1%, 61.5%, 57.1, respectively %, 55.8% for Normal, SA, SC, and SS profiles. A total of 19,090 individual blood culture bottles were collected from 1419 impatient patients as follows: Normal profile (n = 18,042 bottles), AS profile (n = 677 culture bottles), SS profile (n = 362 bottles). The majority of blood culture orders come from pediatric services, accounting for 70% of the total number of orders. Of 19,090 vials examined in this current study, 19.6% developed a positive blood culture. Overall, the most commonly isolated bacteria were Staphylococci (41.1%), Enterobacteriaceae (36.7%), Bacillaceae (10.2%), unfermented (6.30%), Streptococci (5.01%), and a small proportion of yeast (0.75%). There is no significant difference in bacterial spectrum between the SS profile and the normal profile of individuals (p = 0.104). Coagulase-negative staphylococci accounted for 32%, 24%, and 40% of the species isolated in the normal AS and SS profiles. respectively. Coagulase-negative staphylococci were the most commonly isolated organisms in SS. Group E and sptagged streptococci each account for less than 2% of the organisms isolated in SS. Pneumococci were not found. Bacillus accounts for 25% of isolates in SS subjects compared to 9% in normal and AS subjects, respectively. Pseudomonas aeruginosa and Burkholderia cepacia then make up 10% of the isolates in the subjects of the SS profile as non-fermenters. Conclusion: Our study shows that enterobacteria and staph are prevalent in people with sickle cell disease. There is no significant difference in bacterial spectrum between SS subjects compared to subjects with a normal profile. The rarity of Streptococcus pneumoniae in bacteremia isolates underlines the need for further studies with larger patient numbers to better understand the spectrum of bacterial infections in patients with sickle cell disease in West Africa.

Implementation of a Rapid Microarray Assay for the Detection of Gram-Positive, Gram-Negative and Resistance Determinants： Assessing Performance in a Clinical Laboratory in Bulgaria

Two hundred and seven positive blood cultures from two blood culture systems （Bactec and BacTAlert） between May 2012 and February 2014 were enrolled in this study. We present the results of prospectively tested, non-duplicate Gram-positive and Gram-negative organisms tested by the BC-GP （Verigene Gram-positive） and BC-GN （Gram-negative） Blood Culture Assays （Nanosphere, Inc.） for the first time in Bulgaria. These assays represent new tools for the rapid detection of pathogens and resistance markers in blood stream infections. Results of the Verigene System were compared with conventional testing methods. Of the 207 isolates, 180 （87.0%） were targets on the blood culture panels. Correct identification of Gram-positive organisms was 99.2% and of Gram-negative organisms was 98.2% for organisms that could be detected with BC-GP and BC-GN. Additionally, staphylococci tested for the presence of the mecA gene showed a 75.7% correlation with the cefoxitin test and identification of methicillin-resistance by Vitek 2. ESBLs （extended-spectrum beta-lactamases） for Gram-negative organisms were detected by both methods, showing 100% agreement.

Epidemiology of Nosocomial Bacteremia Due to Bacteria from the “<i>Burkholderia cepacia</i>Complex” at Libreville University Hospital Center

Introduction: Burkholderia cepacia is a non-fermenting emergent bacterium common in nosocomial infections and can cause life-threatening infections whose multidrug resistance makes them a serious threat in hospitals. The aim of this study was to determine the prevalence of B. cepacia infections during nosocomial infections at Libreville University teaching hospital. Methodology: In this cross-sectional study, lasting 19 months, 412 blood cultures were analyzed. The BacT/ALERT 3D (Biomerieux, France) was used to detect the positivity of blood culture flasks and the Viteck 2 compact (Biomerieux, France) for the identification of germs and the study of their susceptibility to antibiotics. Results: Our study population consisted of 412 patients. The sex-ratio M/F was 1.06 in favor of the male gender (n = 201, 51%). The age of the patients varied between 0 and 82 years. The bacteremia of B. cepacia mainly affected children under 15 years of age with a prevalence of 7% (n = 28). The pediatric ward was more represented with a frequency of 36% (n = 10). The antibiotic sensitivity profile showed high resistance of 100% for aminoglycosides (amikacin, tobramycin, and gentamycin), tetracycline, beta-lactams (Amoxicillin, Imipenem, Ticarcillin, Cefoxitin and Cefotaxime), and ciprofloxacin. However, four molecules were active on B. cepacia (Levofloxacin 100%, Trimethoprim + sulfamethoxazole 92.3%, ceftazidime 80% and cefepime 35%). Conclusion: Ultimately, infection and multi-resistance due to Burkholderia cepacia calls for a review of hospital hygiene in the pediatric ward and a review of antibiotic therapy in young children.

The clinical differentiation of blood culture-positive and -negative sepsis in burn patients: a retrospective cohort stu

Background:Sepsis is a potentially life-threatening condition that occurs when the body’s response to infection leads to widespread inflammation and tissue damage.Negative cultures can make it difficult for clinicians to make a diagnosis and may raise questions about the validity of the definition of sepsis.In addition,the clinical distinctions between burn patients with blood culturepositive and-negative sepsis are also poorly understood.Therefore,this study aimed to examine the clinical differences between blood culture-positive and-negative sepsis in burn patients in order to improve the understanding of the pathophysiology and epidemiology of sepsis in this population.Methods:This study had a retrospective design,and the participants were adults aged≥18 years.Patients diagnosed with sepsis were divided into two groups based on their blood culture results within 1 week of sepsis diagnosis.Results:We enrolled 1643 patients admitted to our institution’s burn intensive care unit between January 2010 and December 2021.pH,platelet count,bicarbonate and haematocrit were significant in both the positive and negative groups.However,lymphocyte,red cell distribution width and blood urea nitrogen were significant only in the positive group,whereas lactate dehydrogenase was significant only in the negative group.Acinetobacter baumannii,Pseudomonas aeruginosa,and Klebsiella pneumonia are common gram-negative bacterial species,and Staphylococcus aureus and Staphylococcus epidermidis are common gram-positive bacterial species seen in burn patients with positive blood cultures.Carbapenem resistance was found to be associated with an unfavourable prognosis in gram-negative bacteria,with the exception of P.aeruginosa.Conclusions:pH,platelet count,bicarbonate and haematocrit were routine biomarkers that demon-strated statistical significance in both groups.Lactate dehydrogenase was significant in the blood-negative group,while red cell distribution width,blood urea nitrogen and lymphocyte count were significant in the positive group.Furthermore,the most common causes of sepsis are gram-negative bacteria,including A.baumannii,K.pneumoniae and P.aeruginosa.Additionally,resistance to carbapenems is associated with unfavourable outcomes.

Clinical Characteristics and Follow-Up Data in a Series of Twenty Infective Endocarditis Complicated of Rheumatic Manifestations

The infective endocarditis is a septicemia complicated of many systemic manifestations. Rheumatic manifestations can be revelatory, leading sometimes to a lateness diagnosis. The aim of this study is to determine the epidemiological, clinical, bacteriological profile and the follow up in patients affected of an infective endocarditis complicated of rheumatic manifestations. It’s a retrospective study concerning the period from January 1990 to December 2015. The analysis had implicated epidemiological, clinical, biological data, in association to immunological, bacteriological and radiological examinations. All the patients fulfilled the revised Duke’s criteria for the infective endocarditis. Articular and osseous radiographs, blood culture, transthoracic and/or transoesophageal echocardiography were performed in all patients. Twenty patients had rheumatic manifestations. The mean age was 37 years. There were arthralgia in 15 cases, myalgia in 5 cases and arthritis in 8 cases: 6 cases of mono-arthritis and 2 cases of oligo-arthritis. All patients had an inflammatory biological syndrome. The blood culture was positive in all the cases. Echocardiography revealed vegetations in all the patients: mitral in 10 cases, aortic in 4 cases, mitral and aortic in 4 cases, aortic and tricuspid in 1 case, tricuspid in 1 case. The radiological examination found 2 cases of spondylodiscitis and a case of saco-iliitis. The articular outcome was favorable in 17 cases. Three patients had died. The infective endocarditis should be considered in case of febrile arthritis. An early diagnosis and adapted treatment are guarantors of better prognosis.

Blood collection procedures influence contamination rates in blood culture： a prospective study

Background Blood culture contamination is a significant adverse event. The aim of this project was to evaluate the efficacy of a strict blood collection procedure in reducing the blood culture contamination rate. Methods A prospectively controlled study was performed in two different medical areas in Peking Union Medical College Hospital （PUMCH） for 16 months （from May 2006 to September 2007）. In test group, a strict blood collection procedure was carried out by trained nurses with the veinpuncture sites were scrupulously disinfected with 2.5% tincture of iodine plus 70% alcohol. In control group, commonly used procedure in PUMCH was performed with 0.45% chlorhexidine acetate plus 0.2% iodine. Blood culture positive results for 4 target organisms （Coagulase-negafive staphylococci, Propionibacterium acnes, physicians from infectious department to （contamination）. Corynebacterium species and Bacillus determine whether a sample was true species） were further assessed by positive （pathogen） or false positive Results Total 9321 blood culture collections were analyzed. The blood culture contamination rate in test group was significantly lower than that in control group （5/3177 （0.16%） vs. 77/6144 （1.25%）; x2=13.382, P 〈0.001）. The most common contaminant was Coagulase-negative staphylococcus （76.83%）. The average cultural time during which contaminated samples became positive was longer than that for true pathogen samples （42.0 hours vs. 13.9 hours, P=-0.041）. Conclusion Using a strict blood collection procedure can significantly reduce blood culture contamination rate.

Impact of satellite blood culture on early diagnosis of sepsis

Background:The aim of this study was to assess whether satellite blood culture(SBC)can improve turnaround times,antibiotic switching,and patient prognosis,relative to laboratory blood culture(LBC).Methods:Patients with sepsis treated in the intensive care units(ICUs)of Henan Provincial People’s Hospital from February 5,2018 to January 19,2019 who met the inclusion criteria were recruited to the study and divided into the SBC group and LBC group according to different blood culture methods.Patient demographics,blood culture,antibiotic adjustment,and prognosis data were collected and compared between the two groups.Results:A total of 204 blood culture sets from 52 ICU patients,including 100 from the medical microbiology LBC group and 104 from the SBC group,were analyzed in this study.There was no significant difference in the positive rates between the two groups.Time from specimen collection to incubation was significantly shorter in the SBC group than that in the LBC group(1.65 h vs.3.51 h,z=−4.09,P<0.001).The median time from specimen collection to notification of blood culture positivity was 24.83 h in the SBC group and 27.83 h in the LBC group.Median times from adjustment of antibiotics according to the first report were 26.05 h and 51.71 h in the SBC and LBC groups,respectively,while those according to the final report were 97.17 h and 111.45 h,respectively.Median ICU lengths of stay were 15.00 days and 17.00 days in the SBC and LBC groups,respectively,and median ICU lengths of stay were 18.00 days and 23.50 days,respectively.Mean hospitalization costs were 157.99 and 186.73 thousand yuan in the SBC and LBC groups,respectively.Conclusion:SBC can significantly reduce blood culture turnaround times;however,there were no significant differences between the two blood culture methods in initial reporting of positive cultures,time to adjustment of antibiotic therapy,or medical costs,despite a trend toward improvement.

Neonatal sepsis: within and beyond China

Sepsis remains a significant cause of neonatal morbidity and mortality in China.A better understanding of neonatal sepsis in China as compared with other industrialized and non-industrialized countries may help optimize neonatal health care both regionally and globally.Literature cited in this review was retrieved from PubMed using the keywords"neonatal sepsis,""early-onset(EOS)"and"late-onset(LOS)"in English,with the focus set on population-based studies.This review provides an updated summary regarding the epidemiology,pathogen profile,infectious work-up,and empirical treatment of neonatal sepsis within and beyond China.The incidence of neonatal EOS and the proportion of Group B Streptococcus(GBS)within pathogens causing EOS in China seem to differ from those in developed countries,possibly due to different population characteristics and intrapartum/postnatal health care strategies.Whether to adopt GBS screening and intrapartum antibiotic prophylaxis in China remains highly debatable.The pathogen profile of LOS in China was shown to be similar to other countries.However,viruses as potential pathogens of neonatal LOS have been underappreciated.Growing antimicrobial resistance in China reflects limitations in adapting antibiotic regimen to local microbial profile and timely cessation of treatment in non-proven bacterial infections.This review stresses that the local epidemiology of neonatal sepsis should be closely monitored in each institution.A prompt and adequate infectious work-up is critically important in diagnosing neonatal sepsis.Adequate and appropriate antibiotic strategies must be overemphasized to prevent the emergence of multi-resistant bacteria in China.

Retrospective Examination of Q Fever Endocarditis： An Underdiagnosed Disease in the Mainland of China

Background： Q fever endocarditis, a chronic illness caused by Coxiella burnetii, can be fatal ifmisdiagnosed or left untreated. Despite a relatively high positive rate of Q fever serology in healthy individuals in the mainland of China, very few cases of Q fever endocarditis have been reported. This study summarized cases of Q fever endocarditis among blood culture negative endocarditis （BCNE） patients and discussed factors attributing to the low diagnostic rate. Methods： We identified confirmed cases of Q fever endocarditis among 637 consecutive patients with infective endocarditis （IE） in the Peking Union Medical College Hospital between 2006 and 2016. The clinical findings for each confirmed case were recorded. BCNE patients were also examined and each BCNE patient＇s Q fever risk factors were identified. The risk factors and presence of Q fever serologic testing between BCNE patients suspected and unsuspected of Q fever were compared using the Chi-squared or Chi-squared with Yates＇ correction for continuity. Results： Among the IE patients examined, there were 147 BCNE patients, of whom only 11 patients （7.5%） were suspected of Q fever and undergone serological testing for C. burnetii. Six out of 11 suspected cases were diagnosed as Q fever endocarditis. For the remaining 136 BCNE patients, none of them was suspected of Q fever nor underwent relevant testing. Risk factors for Q fever endocarditis were comparable between suspected and unsuspected patients, with the most common risk factors being valvulopathy in both groups. However, significantly more patients had consulted the Infectious Diseases Division and undergone comprehensive diagnostic tests in the suspected group than the unsuspected group （100% vs. 63%, P = 0.03）. Conclusions： Q fever endocarditis is a serious yet treatable condition. Lacking awareness of the disease may prevent BCNE patients from being identified, despite having Q fever risk factors. Increasing awareness and guideline adherence are crucial in avoiding misdiagnosing and missed diagnosing of the disease.

Application of Kaiser Sepsis Calculator in culture-positive infants with early onset sepsis

Background Kaiser Sepsis Calculator(KSC)reduces antibiotic use,testing and intravenous infiltrates but there are concerns about the missed early onset sepsis(EOS)cases.We sought to apply the KSC score for culture-positive infants retrospectively in infants born in the last 10 years in our hospital.Methods In a retrospective cohort study,the comparison groups were divided into Group A(no antibiotics recommended by KSC)and Group B(antibiotics recommended).Results Overall,17/24(71%)infants would have been started on antibiotics per KSC but 7/24(29%)would not.The initial EOS risk was not significantly different between the groups(Group A vs.Group B:0.44 vs.0.76,P=0.41),but the final risk score was(0.33 vs.9.41,P<0.001).In Group A(no antibiotics),3/7 infants became symptomatic between 9 and 42 hours.Conclusion There may be a potential delay in starting antibiotics in infants that are asymptomatic at birth while using KSC.

Leptotrichia hongkongensis sp.nov.,a novel Leptotrichia species with the oral cavity as its natural reservoir

A straight, non-sporulating, Gram-variable bacillus (HKU24T) was recovered from the blood culture of a patient with metastatic breast carcinoma. After repeated subculturing in BACTEC Plus Anaerobic/F blood culture broth, HKU24T grew on brucella agar as non-hemolytic, pinpoint colonies after 96 h of incubation at 37 °C in an anaerobic environment and aerobic environment with 5% CO2. Growth was enhanced with a streak of Staphylococcus aureus. HKU24T was non-motile and catalase-negative, but positive for alkaline phosphatase, β-glucosidase, and α-glucosidase. It hydrolyzed phenylphosphonate and reduced resazurin. 16S rRNA, groEL, gyrB, recA, and rpoB sequencing showed that HKU24T occupies a distinct phylogenetic position among the Leptotrichia species, being most closely related to Leptotrichia trevisanii. Using HKU24T groEL, gyrB, recA, and rpoB gene-specific primers, fragments of these genes were amplified from one of 20 oral specimens. Based on phenotypic and genotypic characteristics, we propose a new species, Leptotrichia hongkongensis sp. nov., to describe this bacterium.