BD BACTEC Research Articles

P-882. Comparison of Epidemiology, Risk factors, Antimicrobial susceptibility and Outcome of Anaerobic Bacteremia: 2011-2013 and 2020- 2022

Abstract Background Anaerobes are again entering the spotlight as patients become more complex and antimicrobial resistances continue to mount as a result of their widespread use. The aim of our study was to compare the incidence, risk factors and susceptibility patterns of anaerobic bacteremia during 1st Jan 2011-31st Dec 2013 (period 1) and 1st Jan 2020-31st Dec 2022 (period 2) in community hospitals and acute care centres in Edmonton and the North Zone in Alberta. The percentages of anaerobic organisms isolated in 2011-2013 and 2020-2022 Methods • Microbiologic data extracted from laboratory information system • Demographic and clinical data extracted from the EMR system • Blood cultures were incubated on the BD BACTEC 9240™ system or the BD BACTEC™ FX Blood Culture System • Organism identification was performed by Vitek® 2 ANC ID card, traditional phenotypic methods, Vitek® MALDI-TOF and, failing these, genomic sequencing • Susceptibility testing by E-test; interpretation as per CLSI or EUCAST guidelines The percentages of susceptible Bacteroides species to different antimicrobials in 2011-2013 and 2020-2022 Results Period 1: 319 anaerobic bacteremia were identified. 247 were included in the study after exclusion of repeat positives (within the first 2 weeks of the first positive culture) and contamination. Total number of isolates were 279 and susceptibilities were available on 252 during this period. Period 2: 830 anaerobic bacteremia were identified. 467 anaerobic bacteremia were included in the study after exclusion of repeat positives and contamination. The total number of isolates were 539 and susceptibilities were available on 417 isolates during this study period. The total number of anaerobic bacteremia almost doubled from 82 cases per year to 156 cases per year during the study decade. The majority were monomicrobial bacteremia (71% and 85%) with the gastrointestinal tract identified as the commonest source. The most common isolated anaerobe was Bacteroides species. Metronidazole susceptibilities for all anaerobes were above 90%. The crude 30-day mortality rates were 22.7% and 25.8% in period 1 and 2 respectively. Conclusion The total number of anaerobic bacteremia increased significantly in the 9-year interval. No significant changes in metronidazole susceptibility were observed between both periods of time. Disclosures All Authors: No reported disclosures

Neonatal septicemia: Diagnostic challenges and the role of CRP and blood culture

Neonatal septicemia, a serious blood infection occurring within the first four weeks of life, is a significant cause of neonatal deaths. Its diagnosis is challenging due to the non-specific nature of its signs and symptoms. C-reactive protein (CRP) serves as a valuable biomarker for early detection, facilitating timely treatment and improving survival rates as a rapid adjunct to the standard blood culture process. This study explores the relationship between CRP levels and blood culture findings in diagnosing Neonatal septicemia. The objectives were to determine common organisms causing neonatal septicemia, to evaluate CRP as a diagnostic tool for Neonatal septicemia compared to blood culture results. The study examined the correlation between CRP levels and blood culture outcomes in neonates suspected of having sepsis. Blood samples were aseptically collected and inoculated in 1 set of BD BACTECTM Peds Plus/F blood culture bottles, incubated for five days using a BD BACTEC automated machine. The bacteria isolated from positive blood culture were processed using Vitek-2. CRP levels were determined using the latex agglutination card test, with positive samples further analyzed via quantitative nephelometry. Of the 321 samples, 28.97% (93) tested positive for bacterial sepsis via blood culture. Among these, 33.3% (31 cases) were , 18.3% (17 cases) were , and 11.8% (11 cases) were , with coagulase-negative staphylococci (CONS) being the most common group overall. Among the Gram-negative organisms, (8.6%) and (6.5%) were significant contributors to neonatal septicemia. CRP was positive in 82 cases with blood culture-positive samples and in 105 cases with blood culture-negative samples, underscoring its potential as a diagnostic marker for Neonatal septicemia. While CRP is a valuable biomarker for detection of Neonatal septicemia, it should not be used as a sole diagnostic tool due to its lack of specificity. CRP testing provides a presumptive diagnosis that can guide early antibiotic therapy, emphasizing its significance in neonatal care.

Etiological profile and antimicrobial susceptibility pattern of blood culture isolates for bloodstream infection

Objectives: The objective of the study is to identify and study the antimicrobial susceptibility pattern of various causative agents of bloodstream infection (BSI) in a tertiary care hospital. Materials and Methods: This was a retrospective observational study conducted from October 2022 to September 2023. Paired blood culture samples were collected aseptically and incubated in BD BACTEC FX-40, a fully automated blood culture system, for 5 days. When the bottle was “flagged positive,” gram staining was done, followed by subculture onto Blood agar and MacConkey agar. Species identification and antibiotic susceptibility testing were performed using the VITEK 2 Compact system and interpreted according to Clinical Laboratory Standard Institute guidelines. Statistical analysis: The data were analyzed using the Statistical Package for the Social Sciences version 20.0. Results: 10,449 blood cultures were received during the 1-year study period, out of which 13.2% (1378 samples) showed growth of pathogenic organisms. Gram-negative bacilli (810/1,378, 58.8%) were the most common etiological agents, and Klebsiella pneumoniae was the most predominant pathogen recovered . Candida spp. were recovered in (150/1378, 10.9%) isolates. A high rate of antimicrobial resistance (AMR) was noted, including (26/46, 56.5%) methicillin-resistant Staphylococcus aureus, (9/125, 7.2%) vancomycin-resistant enterococci, and (269/536, 50.2%) carbapenem-resistant enterobacterales. The current study also highlights high resistance among non-fermenting Gram-negative bacteria. Conclusions: Gram-negative bacilli are the most common cause of BSIs in our setup. A high level of AMR is observed among the pathogens. The formulation of an effective antimicrobial stewardship program and its strict compliance is the need of the hour.

The impact of physiological state and environmental stress on bacterial load estimation methodologies for Mycobacterium tuberculosis

When processed in solid or liquid medium, tuberculosis patient samples yield different proportions of a heterogenous bacterial community over the duration of treatment. We aimed to derive a relationship between methodologies for bacterial load determination and assess the effect of the growth phase of the parent culture and its exposure to stress on the results. Mycobacterium tuberculosis H37Rv was grown with and without antibiotic (isoniazid or rifampicin) and sampled on day 0, 3, 11 and 21 of growth in broth culture. The bacterial load was estimated by colony counts and the BD BACTEC MGIT system. Linear and nonlinear mixed-effects models were used to describe the relationship between time-to-positivity (TTP) and time-to-growth (TTG) versus colony forming units (CFU), and growth units (GU) versus incubation time in MGIT. For samples with the same CFU, antibiotic-treated and stationary phase cells had a shorter TTP than antibiotic-free controls and early-logarithmic phase cells, respectively. Similarly, stationary phase samples reached higher GUs and had shorter TTG than early-log phase ones. This suggests that there is a population of bacterial cells that can be differentially recovered in liquid medium, giving us insight into the physiological states of the original culture, aiding the interpretation of clinical trial outputs.

Validity of reducing blood culture incubation time for the BD BACTEC FX blood culture system considering microbiological and clinical aspects

IntroductionA blood culture (BC) test is vital for diagnosing bacteremia in clinical practice. Although incubation time varies among automated BC systems, 4–5 days is deemed to be sufficient time for the BD BACTEC FX blood culture system. This study compared the clinical and microbiological characteristics of true-positive BC samples on day 5 with those within 4 days to reduce missed true bacteremia cases. MethodsWe conducted a retrospective study of blood cultures from hospitalized patients between April 2020 and April 2023 at a tertiary care hospital in Japan. ResultsIn total, 12,342 BC sets were collected from 6,567 patients. Gram-positive bacilli other than Bacillus spp. and Corynebacterium spp., non-albicans Candida, and yeasts other than Candida spp. were detected more frequently in BC-positive patients on day 5 than in those within 4 days. The gastrointestinal tract was the portal of entry more frequently on day 5 than within 4 days (25 % vs. 4 %, p = 0.006). ConclusionA 4-day incubation period is sufficient for the BD BACTEC FX blood culture system under routine conditions. However, a 5-day incubation period may be warranted when low pathogenicity is suspected or the gastrointestinal tract is suspected as the portal of entry.

Drug resistance and genomic variations among Mycobacterium tuberculosis isolates from The Nile Delta, Egypt

Tuberculosis is a global public health concern. Earlier reports suggested the emergence of high rates of drug resistant tuberculosis in Egypt. This study included 102 isolates of Mycobacterium tuberculosis collected from two reference laboratories in Cairo and Alexandria. All clinical isolates were sub-cultured on Löwenstein–Jensen medium and analyzed using both BD BACTEC MGIT 960 SIRE Kit and standard diffusion disk assays to identify the antibiotic sensitivity profile. Extracted genomic DNA was subjected to whole genome sequencing (WGS) using Illumina platform. Isolates that belong to lineage 4 represented > 80%, while lineage 3 represented only 11% of the isolates. The percentage of drug resistance for the streptomycin, isoniazid, rifampicin and ethambutol were 31.0, 17.2, 19.5 and 20.7, respectively. Nearly 47.1% of the isolates were sensitive to the four anti-tuberculous drugs, while only one isolate was resistant to all four drugs. In addition, several new and known mutations were identified by WGS. High rates of drug resistance and new mutations were identified in our isolates. Tuberculosis control measures should focus on the spread of mono (S, I, R, E)- and double (S, E)-drug resistant strains present at higher rates throughout the whole Nile Delta, Egypt.

Evaluation of BACTEC™ FX and BacT/Alert™ Automated Blood Culture Systems for Detection of Clinically Relevant Bacterial and Yeast Species

Background: Bloodstream infections (BSI) are a significant health concern, necessitating effective diagnostic tools. This study evaluates the performance of the BD Bactec FX system in comparison to the established BacT/Alert system, examining mean time till detection (TTD) across various blood culture bottles.Methods: The study involves 148 blood culture bottles, inoculated with representative bacterial ATCC strains (n= 15) and 04 yeast isolates. Parallel testing is conducted by seeding 10–30 colony-forming units (CFU) in duplicate in both BD Bactec FX and BacT/Alert systems. TTD is assessed across aerobic, anaerobic, and pediatric bottles for diverse microbial species.Results: All 148 bottles tested in parallel show positive signals in both systems. BD Bactec FX demonstrates significantly shorter TTD for adult-seeded cultures in aerobic and anaerobic bottles compared to BacT/Alert Similarly, pediatric bottles with BD Bactec FX exhibit a shorter TTD compared to BacT/Alert. The statistical significance of TTD, 95% confidence intervals (CI), and p-values is evident for Bactec FX aerobic, anaerobic, and pediatric bottles across tested organisms. Notable examples of faster TTD include; Bacteroides ovatus (16.6h by Bactec FX vs. 70.5h by Bact/Alert 3D), Stenotrophomonas maltophilia (33.7h vs. 72.5h), and Streptococcus pyogenes (8.1h vs. 11.9h).Conclusions: In conclusion, the study’s findings demonstrate that BD Bactec FX surpasses BacT/Alert in prompt microbial detection, showcasing potential for early identification of bacteremia and fungemia. Faster TTD implies the potential to initiate timely antimicrobial treatment, thereby reducing patient morbidity and mortality. However, exceptions in certain microbial species highlight the need for comprehensive clinical validation to establish the broad applicability of these findings.Keywords: Blood Culture System; Recovery Rate; Time to detection; Blood stream infection; BTA3D; Bactec FX

Current trends in antimicrobial resistance of ESKAPEEc pathogens from bloodstream infections – Experience of a tertiary care centre in North India

IntroductionBloodstream infections (BSI) due to ESKAPEEc pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanni, Pseudomonas aeruginosa, Enterobacter spp. and Escherichia coli), cause significant mobility and mortality worldwide and are among the most common healthcare associated infections. Rising rates of antimicrobial resistance (AMR) in India are alarming, because of the high infection rates and poor control of antibiotic use. This single-centre, retrospective study was undertaken to identify the patterns of distribution and antimicrobial resistance of ESKAPEEc pathogens in bloodstream infections. MethodologyBlood samples from patients with suspected BSI were cultured and antimicrobial susceptibility testing was performed on automated systems (BD Bactec Fx/BactAlert 3D and Vitek2). The microbiological data on bacterial BSI was retrieved from the laboratory records and antimicrobial resistance profiles were analysed. Results10.7% of the blood culture samples showed bacterial growth during the study period (adult > paediatric and intensive care unit (ICU) > ward > outpatient department (OPD)). E. coli (24%) and K. pneumoniae (20.5%) were the predominant species isolated, followed by S. aureus (9.5%) and A. baumanni (9%). High rates of resistance to third generation cephalosporins, β-lactam-β-lactamase inhibitor combinations (BL-BLI) and carbapenems was observed, in Gram-negative isolates, especially from ICU patients. Methicillin-resistant S. aureus (MRSA) isolates increased from 67% to 88% over the five-year period. Vancomycin-resistance among Enterococcus isolates also escalated to 40% in 2022 with 11% linezolid resistance. ConclusionThe study revealed that more than 77% of bloodstream infections were caused by ESKAPEEc pathogens, with high rates of resistance to most antimicrobials. This reinforces the importance of monitoring the frequency of bacteria and antibiograms in individual treatment and hospital infection control programs.

The effect of taurolidine on the time-to-positivity of blood cultures

Taurolidine containing lock solutions (TL) are a promising method for the prevention of central line associated bloodstream infections. Per accident, the TL may not always be aspirated from the central venous catheter (CVC) before blood cultures are obtained. The TL could, unintentionally, end up in a blood culture vial, possibly altering the results. The aim of this study was to investigate the effect of the TLs on the detection of microbial growth in blood culture vials. Different lock solutions (taurolidine-citrate-heparin (TCHL), taurolidine, heparin, citrate or NaCl) were added to BD BACTECTM blood culture vials (Plus Aerobic/F, Lytic/10 Anaerobic/F or Peds Plus/F) before spiking with Staphylococcus aureus (ATCC 29213 or a clinical strain) or Escherichia coli (ATCC 25922 or a clinical strain) in the presence and absence of blood. Subsequently, blood culture vials were incubated in the BD BACTEC FX instrument with Time-to-positivity (TTP) as primary outcome. In addition, the effect of the TCHL on a variety of other micro-organisms was tested. In the presence of taurolidine, the TTP was considerably delayed or vials even remained negative as compared to vials containing heparin, citrate or NaCl. This effect was dose-dependent. The delayed TTP was much less pronounced in the presence of blood, but still notable. This study stresses the clinical importance of discarding TLs from the CVC before obtaining a blood culture.

A modified decontamination and storage method for sputum from patients with tuberculosis.

Collecting and storing large number of sputum samples with a view to culturing these in the future requires an efficient initial handling method. We devised a modified sputum digestion and decontamination method that maximised storage capacity and Mycobacterium tuberculosis (M.tb) recovery from culture while minimising laboratory workload and risk of contamination. We collected smear microscopy positive sputum samples from patients with pulmonary tuberculosis (TB). The sputum samples were split and processed using both the standard N-Acetyl-L-cysteine and sodium hydroxide (NALC-NaOH) method and our modified method before freezing and later culturing in BD BACTEC 960 Mycobacterium Growth Indicator Tubes (MGIT) system. We assessed the Time to Positivity (TPP) and Growth Unit (GU) data. We selected 22 sputum samples to compare two digestion and decontamination methods. The samples that underwent the modified method had longer TTP (p < 0.05) but similar GU in comparison to standard method. Overall, 1/22 samples failed to grow in MGIT after being processed by the modified method. We then applied the modified method to 348 sputum samples with Rifampicin resistance detected by GeneXpert MTB/RIF assay, which were frozen for between 1-25 months. The overall MGIT positive, negative, and contamination rate was 90.5%, 7.8%, and 1.7%, respectively. There was no significant difference in MGIT result when samples were grouped by duration of storage or positive smear grade. Our modified method yielded acceptable M.tb recovery rate and low contamination risk while allowing us to collect and store thousands of sputum samples over a long period of time for future tests.

Performance evaluation of 4-day versus 5-day blood cultures using the BD BACTEC FX system

Background: Blood culture (BC) systems have evolved to increase sensitivity and reduce turnaround times. This study compared the performance of a 4-day versus a 5-day BC incubation period using the BD BACTEC™ FX (Becton, Dickinson and Company, USA). Methods: A total of 37,379 consecutive sets of BC were evaluated over a 3-month period in a 2,700-bed tertiary care hospital. Positive BC results were reviewed to assess time-to-positivity (TTP) and species identification of the isolates. The BCs were performed in pairs of vials, utilizing either BD BACTEC Plus Aerobic/F or Peds Plus/F with BD BACTEC Lytic Anaerobic media. Results: A total of 14,899 episodes, averaging 2.51 sets per episode, were analyzed. Of these, 1,398 (9.38%) were positive, yielding 1,465 isolates. TTP (hours) were &lt; 12 in 48.87%, 12-24 in 31.40%, 24-48 in 13.38%, 48-72 in 3.28%, 72-96 in 1.43%, and &gt;96 in 1.64%. The two most prevalent organisms, Escherichia coli and Klebsiella spp. were detected within 12 hours in 88.75% and 78.90%, respectively. The respective median TTP (T50) values for E. coli, Klebsiella spp., Enterococcus faecalis/E. faecium, and Staphylococcus aureus were 9.24, 9.60, 13.75, and 14.20. T50 values for these species were significantly shorter in anaerobic bottles than in aerobic bottles. Of 24 BCs with TTP &gt; 96, only 4 containing anaerobic bacteria or molds were f irst detected after 96 hours. Conclusion: A 4-day incubation has demonstrated excellent sensitivity. However, a 5-day incubation may be beneficial for hospitals caring for patients at high risk for infections with slow-growing fungi or fastidious bacteria.

Molecular epidemiology and drug sensitivity of Mycobacterium tuberculosis in homeless individuals in the Addis Ababa city, Ethiopia

Although homeless segment of the society could be the hotspots for tuberculosis (TB) transmission, there is little data on TB in homeless individuals in Ethiopia. The objective of this study was to investigate the molecular epidemiology and drug sensitivity of Mycobacterium tuberculosis (M. tuberculosis) isolated from homeless individuals in Addis Ababa, Ethiopia. The study was conducted on 59 M. tuberculosis isolates, which were recovered by the clinical screening of 5600 homeless individuals and bacteriological examination of 641 individuals with symptoms of pulmonary tuberculosis (PTB). Region of difference-9 (RD9) based polymerase-chain reaction (PCR), Spoligotyping and 24-loci Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem Repeat (MIRU-VNTR) typing were used for genotyping of the isolates. In addition, drug sensitivity test was performed on the isolates using BD Bactec Mycobacterial Growth Inhibition Tube (MGIT) 960. Fifty-eight of the 59 isolates were positive by spoligotyping and spoligotyping International type (SIT) 53, SIT 37, and SIT 149 were the dominant spoligotypes; each consisting of 19%, 15.5%, and10.3% of the isolates, respectively. The majority of the isolates (89.7%) were members of the Euro-American (EA) major lineage. MIRU-VNTR identified Ethiopia_3, Delhi/CAS, Ethiopia_2, TUR, X-type, Ethiopia_H37Rv-like strain, Haarlem and Latin-American Mediterranean (LAM) sub lineages. The proportion of clustering was 77.6% (45/58) in spoligotyping while it was 39.7% (23/58) in 24-loci MIRU-VNTR typing. Furthermore, the proportion of clustering was significantly lowered to 10.3% (6/58) when a combination of spoligotyping and 24-loci MIRU-VNTRplus was used. The recent transmission index (RTI) recorded by spoligotyping, 24-loci MIRU-VNTR typing, and a combination of the two genotyping methods were 58.6%, 27.6% and 5.2%, respectively. Young age and living in groups were significantly associated with strain clustering (P < 0.05). The drug sensitivity test (DST) result showed 8.9% (4/58) of the isolates were resistant to one or more first line ant-TB drugs; but multidrug resistant isolate was not detected. Clustering and RTI could suggest the transmission of TB in the homeless individuals, which could suggest a similar pattern of transmission between homeless individuals and the general population. Hence, the TB control program should consider homeless individuals during the implementation of TB control program.

591. Positivity of Blood Culture on Automated Incubation System After 72 Hours and Clinical Significance from the Large United States Tertiary Care Center

Abstract Background Hospitals commonly use automated blood culture incubation systems that provide continuous monitoring for routine blood cultures. Detecting microorganisms early on can help optimize the utilization of antibiotics (ABx) and enable clinicians to de-escalate or discontinue ABx as necessary, making it an important aspect of antimicrobial stewardship. The BD BACTEC Fx, an automated system for blood culture incubation, holds blood culture bottles until growth is demonstrated or for five days unless an extended incubation period is requested by the infectious disease physician. We conducted a clinical evaluation of the significance of positive blood cultures after 72 hours of incubation time. Methods After receiving approval from the institutional review board (IRB), we obtained positive blood cultures from July 2017 to June 2020, which we then stratified based on positivity from day one to day five. To evaluate clinical significance, we retrospectively reviewed charts for positive blood culture results on day four and day five. An Infectious Diseases subspecialty team determined the clinical significance of each case. Results During the time frame of July 2017 to June 2020, there were 120,320 blood cultures taken. Out of these, 7,558 were determined to be positive, with 76 being positive on day 4 and 22 being positive on day 5. Upon further inspection of patients with positive blood cultures, it was discovered that repeat blood cultures continued to be positive due to either untreated sources or a high burden of bacteremia. It was also found that bottles containing fungus, particularly candida glabrata and candida albicans, tested positive on day 4 requiring treatment. Table 1 and Table 2 contain more detailed results. Blood cultures positive on day 4 Blood cultures positive on day 4 and clinical significance Blood cultures positive on day 5 Blood cultures positive on day 5 and clinical significance Conclusion In our study we have found that not all positive blood cultures at 72 hours translate into clinical scenarios requiring antibiotic therapy. In fact, prolonged antimicrobial treatment in such cases may lead to unnecessary exposure to antibiotics and increased risk of antibiotic resistance. It is important to consider the full context of clinical and laboratory findings when interpreting blood culture results, as well as any potential sources of contamination. Disclosures All Authors: No reported disclosures

Gender and Age Dependent Bacteriological Etiology of Community-Acquired Blood Stream Infection

Background: Bloodstream infection constitutes one of the most serious situations in infectious disease. Objective: The purpose of the presents study was to determine the gender and age dependent etiology of community- acquired urinary blood stream infection. Methodology: This was a retrospective analysis of blood samples from clinically suspected cases of blood stream infection. Samples were collected at Ad-din Women’s Medical College Hospital, Dhaka &amp; Rushmono Specialized Hospital, Dhaka from January 2018 to September 2018. All the samples were collected from inpatient’s and outpatient’s department of our hospital during the study period and processed in Microbiology laboratory. The BD BACTEC FX40 automated blood culture method was used to isolate bacterial pathogens and antimicrobial susceptibility test was performed by Kirby-Bauer disc diffusion method. Results: A total of 483 (16.1%) pathogens were isolated from 3018 bacteremia suspect patient blood specimens. Gram-negative cocci (58.4%) were predominant organisms recovered followed by Gram-positive bacilli (41.6%). Majority of BSI were caused by Gram negative bacteria predominantly Salmonella Typhi (31.1%). Salmonella species was found less prevalent in the children (55%) and more frequent in the age groups 16 to 30 years (85.0%) and more than 60 years (100.0%). Acinetobacter species was found less prevalent in age group 16 to 30 years (7.5%). Escherichia coli was found only few prevalent in the 1 to 15 (0.5%) and higher frequent in the age groups 16 to 30 years (2.5%). Salmonella species isolates appeared to be sensitive to ceftriaxone (91.3%), meropenem (90.7%) and cotrimoxazole (76%). Sensitivity rates of ciprofloxacin, gentamycin and levofloxacin were 87.3% for coagulase-negative Staphylococcus species (CoNS). Conclusion: Both patients’ age and gender are significant factors in determining bloodstream infection. Bangladesh Journal of Medical Microbiology, January 2023;17(1):3-9

Evaluation of Blood Cultures from SARS-CoV-2-Positive and Negative Adult Patients.

Bacteremia and fungemia are significant causes of morbidity and mortality that frequently occur as co-infections with viral respiratory infections, including SARS-CoV-2. The aim of this study was to evaluate the microorganisms that were isolated from the blood cultures of SARS-CoV-2-positive and negative patients and investigate their antimicrobial resistance patterns. A retrospective analysis was performed of 22,944 blood cultures sent to the laboratory between November 2020 and December 2021. Blood culture analyses were performed using the BD Bactec FX automated system. Identification was carried out using conventional methods, namely, VITEK-2 and MALDI-TOF MS. Antibacterial/antifungal susceptibility tests were performed according to EUCAST/CLSI recommendations. SARS-CoV-2 tests were performed with RT-PCR. Culture positivity was detected in 1630 samples from 652 patients. Of these 652 patients, 633 were tested for SARS-CoV-2; 118 (18.6%) were positive and 515 (81.3%) were negative. The bacteria and fungi that were isolated at the highest rate in SARS-CoV-2-positive patients were methicillin-resistant coagulase-negative staphylococci (MR-CoNS) (21.5%), Escherichia coli (12.4%), Klebsiella pneumoniae (12.4%), Candida albicans (1.65%), and Candida glabrata complex (1.65%), while in the negative patients, the highest rates were for E. coli (21.3%), MR-CoNS (13.5%), K. pneumoniae (12.05%), C. albicans (2.1%), Candida parapsilosis (1.1%), and Candida tropicalis (0.9%). No statistically significant difference was determined between COVID-19-positive and negative patients in terms of detection, such as with the Pseudomonas spp., Enterococcus spp., and methicillin-resistant Staphylococcus aureus isolated from the blood cultures (p > 0.05). The most common isolate was MR-CoNS in SARS-CoV-2-positive patients (p = 0.028). Acinetobacter baumannii was more frequent (p = 0.004) and carbapenem-resistant K. pneumoniae was isolated at a higher rate (60% vs. 43%) in SARS-CoV-2-positive patients compared to SARS-CoV-2-negative patients (p > 0.05). These findings highlight the fact that isolation procedures should not be disregarded and the distribution of bacterial/fungal agents of bloodstream infections and their antibiotic resistance should be followed up during a pandemic, such as in the case of COVID-19.

Assessment of Bacterial Profile and Antimicrobial Susceptibility Pattern of Bacterial Isolates from Blood Culture in Tertiary Level Paediatric Hospital of Nepal

Introduction: Bloodstream infection is a major cause of morbidity and mortality which requires antibiotic treatment. Antimicrobial resistance is an emerging serious public health threat in both developed and developing countries. Children are more susceptible to infections requiring an appropriate choice of antibiotic based on blood culture. This study aims to investigate the bacteriological profile and antibiotic sensitivity pattern of blood culture isolates and compare the yield of bacterial growth between Brain Heart Infusion Broth (BHIB) or BD BACTEC culture media.&#x0D; Methods: A total of 12,795 blood samples were sent for bacteriological culture either for BHIB or BACTEC techniques, 10994 and 1801 samples respectively. Chi-square test was used for showing association between BACTEC and BHIB among isolates.&#x0D; Results: The findings showed that the BACTEC method detected more positive isolates than the BHIB method. The rate of isolation was found highest among children under five years. The most common pathogens isolated were Staphylococcus species (28.1%), Staphylococcus aureus (25.6%), Acinetobacter species (12%), Pseudomonas species (8.2%), Klebsiella species (6.6%), CONS (4.4%), Escherichia coli (4.4%), Salmonella Typhi (3.5%), Enterobacter species (3.2%) and Streptococcus species (0.3%).&#x0D; Conclusions: Staphylococcus aureus was the commonest isolate identified in the current study. BACTEC culture method detected the higher percentage of isolates than BHIB method.

The Role of Automation for Early Diagnosis of Non-fermenter Superbugs in Critically Ill Septicemic Hospitalized Patients.

Introduction Non-fermenting Gram-negative bacilli (NFGNB) are emerging superbugs of bloodstream infections (BSI), causing increased mortality in hospitalized patients. NFGNB are challenging to identify using conventional identification techniques. Hence, automation is beneficial for accurate and fast diagnosis; it also facilitates rapid treatment and recovery of patients. This study aims to isolate/identify NFGNB from BSI and determine its antimicrobial susceptibility pattern. Material and methods This study was conducted in the Department of Microbiology, LLRMMC, Meerut, for a period of six months (June to November 2022). The samples were processed using automated blood culture (BD BACTEC) and an identification/sensitivity testing system (BD Phoenix). Results Out of 1340 blood cultures, 347 (25.7%) were flagged positive for microbial growth. A total of 103 (7.6%) NFGNB were isolated, showing their strong association with BSI. The NFGNB isolates were Pseudomonas species 23 (22.3%), Acinetobacter baumannii 19 (18.4%), Salmonella spp. 19 (18.4%), Sphingomonas paucimobilis 17 (16.5%), Aeromonas hydrophila 5 (4.8%), Rhizobium radiobacter sp. 4 (3.8%), Stenotrophomonas maltophila 3 (2.9%), Burkholderia cepacian 3 (2.9%), Proteus mirabilis 2 (1.9%), Achromobacter xylosoxidans 2 (1.9%), Elizabethkingia meningoseptica 2 (1.9%), Ochromobacter anthropic 2 (1.9%), Cuprivadus pauculus 1 (0.9%), and Ralstonia mannitolilytica 1 (0.9%). Conclusions Automation helps in the prompt reporting of NFGNB and their antibiogram pattern by microbiology laboratories, facilitating the early and accurate management of patients with BSI.

The Epidemiology and Incidence of Bloodstream Infections (BSIs) in Under-Five Children in a Tertiary Care Hospital of Northern India – IGMC Shimla

Background: Clinical and diagnostic challenges are due to the result of a variable presentation of neonatal sepsis and bloodstream infections (BSIs) and uncertain disease epidemiology in children below five years of age. Although the criteria for achieving an adequate blood culture specimen in adults have been well described, there is much more equivocation in the pediatric population, especially for the under-five-year age group. Therefore, the present study is designed to evaluate the etiological profile of BSI among under-five children by the automated BACTEC systems. Materials and Methods: All blood culture samples received in the Department of Microbiology for culture falling in the age group were included in the study for a period of one year from 01 July 2015 to 30 June 2016 using the BD BACTEC FX except in the exclusion criteria. The blood culture was observed in the BD BACTEC FX system for at least five days before being reported as sterile. Results: A total of 1533 samples in the age group of &lt; 5 years and suspected of BSIs were received in the Department of Microbiology, Indira Gandhi Medical College (IGMC), Shimla. Among them, 963 (62.8%) were males, while 570 (37.2%) were females. Among the total of 1533 samples, 604 (39.40%) were found positive in culture, 898 (58.57%) were negative, and 31 (2.02%) were contaminants. Among the 604 positive cases, 390 (64.6%) were men, while 214 (35.4%) were women. S. aureus was the highest among the gram-positive isolates 98 (16.22%), followed by coagulase-negative Staphylococcus, group B Streptococcus, and S. pneumoniae. Among the gram-negative organisms, E. coli 80 (13.24%) was isolated mostly followed by K. pneumoniae 70 (11.58%), P. aeruginosa 68 (11.25%), Salmonella typhi 50 (8.27%), Citrobacter koseri 18 (2.98%), Acinetobacter baumannii 12 (1.98%) and a group of organisms without fermentation 86 (14.23%). Conclusion: There was quite high positivity in culture in the preschool group. Positivity was significantly high in males as compared to females. It is essential to administer appropriate and synergistic antimicrobial agents empirically early and appropriately for treating children under five-year age with BSI.

Characteristics of TB/HIV Co-Infection and Patterns of Multidrug-Resistance Tuberculosis in the Northwest Amhara, Ethiopia.

Multidrug-resistant tuberculosis (MDR-TB) has continued to be a serious public health threat and significantly challenges global TB control and prevention efforts, where the TB/HIV co-infection epidemic makes the situation much worse. The aim of the study was to determine the determinant factors associated with patterns of MDR-TB among pulmonary TB patients in the Northwest Amhara, Ethiopia. A hospital-based cross-sectional study was conducted from May 2022 to February 2023 in the Northwest Amhara, Ethiopia. Data on the participants' socio-demographics and clinical characteristics were obtained using a pre-tested checklist. Phenotypic susceptibility testing to first-line anti-TB drugs was performed on 180 isolates by automated BD BACTEC MGIT 960 system. Logistic regression analysis was performed to determine the association of risk factors with patterns of MDR-TB. A p-value ≤0.05 was considered statistically significant. The overall proportion of TB with HIV co-infected cases was 19.8% (50/252). Culture positivity was confirmed in 203/252 (80.6%) of sputum samples. Among 168 isolates, the DST showed that 119 (70.8%) isolates were pan-susceptible to all first-line drugs and prevalence of any resistance to first-line drugs was 49,168 (29.2%). Among the resistant isolates, 28 (16.7%) were any mono-resistance and 12 (7.1%) were determined to be resistant to MDR-TB. TB with a previous TB treatment (aOR = 6.73, 95% CI: 1.78-25.47, p = 0.005) and HIV co-infected (aOR = 0.252, 95% CI: 0.73-0.875, p = 0.03) were significantly associated with MDR-TB. Higher prevalence of TB and MDR-TB was examined among TB patients in the study area. In the study, history of previous TB treatment was the strongest risk factor MDR-TB infection followed by TB with HIV co-infected cases. Therefore, there is a need of strengthening TB control and prevention programs to reduce the increase of TB incidence, further emergence and transmission of a public health threat of MDR-TB cases.

Different BD BACTEC™ Blood Culture Bottle Types for the Detection of Fungi in Simulated Sterile Body Fluid Samples.

Blood culture systems are a potential alternative to classical cultivation of fungi on mycological media, but there are limited data on the suitability of these systems for culturing other sample types (e.g., sterile body fluids). We conducted a prospective study to evaluate different types of blood culture (BC) bottles for the detection of different fungal species in non-blood samples. A total of 43 fungal isolates were tested for their ability to grow in BD BACTEC Mycosis-IC/F (Mycosis bottles), BD BACTEC Plus Aerobic/F (Aerobic bottles) and BD BACTEC Plus Anaerobic/F (Anaerobic bottles) (Becton Dickinson, East Rutherford, NJ, USA) BC bottles inoculated with spiked samples without the addition of blood or fastidious organism supplement. Time to detection (TTD) was determined for all BC types tested and compared between groups. In general, Mycosis and Aerobic bottles were similar (p > 0.05). The Anaerobic bottles failed to support growth in >86% of cases. The Mycosis bottles were superior in detecting Candida glabrata, Cryptococcus spp. and Aspergillus spp. (p < 0.05). The performance of Mycosis and Aerobic bottles was similar, but if cryptococcosis or aspergillosis is suspected, the use of Mycosis bottles is recommended. Anaerobic bottles are not recommended for fungal detection.