Clinical Laboratory Standards Institute Research Articles

Isolation and characterization of enterococci from poultry reveals high incidence of Enterococcus thailandicus in Victoria, Australia.

Antibiotic resistance is a global health crisis. Roughly two-thirds of all antibiotics used are in production animals, which have the potential to impact the development of antibiotic resistance in bacterial pathogens of humans. There is little visibility on the extent of antibiotic resistance in the Australian food chain. This study sought to establish the incidence of antibiotic resistance among enterococci from poultry in Victoria. In 2016, poultry from a Victorian processing facility were swabbed immediately post-slaughter and cultured for Enterococcus species. All isolates recovered were speciated and tested for antibiotic susceptibility to 12 antibiotics following the Clinical Laboratory Standards Institute guidelines. A total of 6 farms and 207 birds were sampled and from these 285 isolates of Enterococcus were recovered. Eight different enterococcal species were identified as follows: E. faecalis (n=122; 43%), E. faecium (n=92; 32%), E. durans (n=35; 12%), E. thailandicus (n=23; 8%), E. hirae (n=10; 3%), and a single each of E. avium, E. gallinarum, and E. mundtii. Reduced susceptibility to older classes of antibiotics was common, in particular: erythromycin (73%), rifampin (49%), nitrofurantoin (40%), and ciprofloxacin (39%). Two vancomycin-intermediate isolates were recovered, but no resistance was detected to either linezolid or gentamicin. The relatively high numbers of a recently described species, E. thailandicus, suggest this species might be well adapted to colonize poultry. The incidence of antibiotic resistance is lower in isolates from poultry than in human medicine in Australia. These results suggest that poultry may serve as a reservoir for older antibiotic resistance genes but is not driving the emergence of antimicrobial resistance in human bacterial pathogens. This is supported by the absence of resistance to linezolid and gentamicin.

Bacterial vaginosis (BV) and Trichomonas vaginalis (TV) co-infection, and bacterial antibiogram profile of pregnant women studied in Lagos, Nigeria

AimThis study was undertaken to determine the prevalence of Bacterial Vaginosis (BV), Trichomonas Vaginalis (TV) co-infection, and the antibacterial sensitivity profile of bacterial isolates.MethodsThe study was a cross-sectional study of 232 pregnant women on a routine antenatal visit between April 2019 and Sept. 2020, at Amukoko clinic in Lagos, Nigeria. The gynaecologist conducted the clinical examination on each patient looking for vaginal discharge and its consistency/homogeneity, colour and odour. Two High Vaginal Swab (HVS) samples were taken from every patient and a semi-structured questionnaire was used to gather the socio-demographic, practices/attitudes, and clinical information of each participant. One sample was employed for wet preparation to identify the TV and BV diagnosis using Amsel’s criteria and Whiff’s test. The second sample was used for bacterial culture and antibiogram was conducted using the disc diffusion technique. The Clinical Laboratory Standard Institutes’ (CLSI) interpretative criteria were used to categorise the results.ResultsThe mean age of the clients was 28.11 ± 7.08 years of age. The majority (88%) were aged 15–35 years. Only 81 (34.9%) had microbial organisms isolated or seen from their specimens and 19 (8.2%) of such were classified as having BV (Bacteriods or Gardnerella isolated). Of the 81 infected, 33 (40.8%) had only bacterial infection, 36 (44.4%) had TV alone and 12 (14.8%) had bacteria co-infected with TV. From the clinical records, the population that was classified as having UTI or vaginitis was only 46 (20.7%) The study observed age (15–35 years) related association between vaginosis/ TV co-infection (X2 = 7.9; P = 0.005). Participants with symptoms of vaginitis or UTI (mainly E. coli & pseudomonas spp. isolated), BV/co-infection with TV significantly associated with female traders (X2 = 8.5; P = 0.003) and were more associated with those from polygamous relationships (X2 = 18.79, P = 0.0001). Women in their 3rd and 2nd. trimester were more significantly associated with vaginal infection (X2 = 9.47, P = 0.002; X2 = 4.79, P = 0.029) respectively. The Pseudomonas showed susceptibility to ciprofloxacin (CIP) and cefuroxime (CXM). While, E. coli isolates were susceptible to cefepime, ciprofloxacin, and imipenem.ConclusionThere is a relatively low prevalence of BV and flagellate co-infection in the community studied.RecommendationWe recommend screening of antenatal women with underlying symptoms for BV and flagellates co-infection to avoid its progression to vaginitis.

Complete Blood Count and Biochemistry Reference Intervals for Healthy Adult Donkeys in the United States.

Previous hematologic and serum biochemistry reference interval (RI) values have been established for donkeys in various geographic regions, life-stages, or for specific donkey breeds. The last extensive investigation establishing RIs for adult donkeys in the United States (U.S.) was published over three decades ago. We aimed to establish updated robust RIs using a reference population of apparently healthy adult donkeys from across the U.S. Standard sized (n = 102), miniature (n = 17), and mammoth (n = 1) donkeys from four different states were enrolled, with 20% of the study population including donkeys captured directly from the wild in Death Valley National Park, CA. RIs were established in accordance with the American Society for Veterinary Clinical Pathology and Clinical Laboratory Standards Institute guidelines. The findings will assist practitioners with the interpretation of their complete blood count and biochemistry panel results in U.S. donkeys. This study also highlights a comparison of results for some important analytes in U.S. donkeys compared to U.S. horses and previously established donkey RIs.

Back to Basics: Blood Culture Contamination Reduction Across a Multicenter Academic Health System

Background: Blood culture contamination is common in healthcare and contributes to diagnostic uncertainty, unnecessary treatments and follow-up testing, increased length of stay, higher rates of reportable healthcare-associated infections and events, over utilization of resources and staff including consultative care, and undue emotional stress to patients. The national benchmark for institutional blood culture contamination rates as recommended by The American Society for Microbiology (ASM) and the Clinical Laboratory Standards Institute (CLSI) is < 3 %. Our institution’s overall rate was 8.9% with the highest burden being from our Emergency Department (ED) locations. We formed a multidisciplinary team aimed to reduce these rates through efforts centered around education and simplification of the collection process. Method: Working closely with and gathering feedback from nursing staff, nurse educators, and supply chain, we developed a blood culture collection kit that included all items necessary for blood culture collection thus eliminating the need for nurses to gather these items individually prior to collection. Additionally, simple step-by-step educational materials (Fig. 1) detailing the collection technique were provided. Education was presented at nursing huddles and skills fairs prior to kit roll-out. Blood culture kits were then stocked in place of individual blood culture collection bottles in all ED stock rooms in August 2022. Result: The 12-week pre-intervention period found 249 contamination events from 4265 total collections deriving a contamination rate of 5.8% across our health system’s four ED locations. During a 12-week post-intervention period following kit roll-out, 116 contamination events occurred from 3629 total collections deriving a contamination rate of 3.2% across our four ED locations. Given our results, we ultimately rolled this out to all units in all locations of our health system. When including all time from kit rollout to present (August 2022 to November 2023, 16 months), there were 1077 contamination events from 43379 total collections deriving an overall contamination rate of 2.5%. When compared to the 16 months prior to the kit rollout (April 2021 to July 2022) there were 1803 contamination events in 49335 total collections (3.7% contamination rate) deriving an overall percent reduction of 32.1%. Conclusion: We were able to decrease our health system’s blood culture contamination rate through simple interventions aimed at reducing the mental burden on nursing staff by developing a blood culture collection kit and educational materials. Since implementation of the kits, we have continued to maintain lower contamination rates as evident by our 16 month follow up period.

Piperacillin/tazobactam Susceptibility Test Interpretive Criteria for Enterobacterales: Recommendations from the United States Committee on Antimicrobial Susceptibility Testing.

The in vitro susceptibility testing interpretive criteria (STIC) for TZP against Enterobacterales were recently updated by the Food and Drug Administration (FDA), Clinical & Laboratory Standards Institute (CLSI), and European Committee on Antimicrobial Susceptibility Testing (EUCAST). The United States Committee on Antimicrobial Susceptibility Testing (USCAST) also recently reviewed TZP STIC for Enterobacterales and arrived at different STIC for Enterobacterales and herein we explain our recommendations and rationale behind them. Based on our review of the available data, USCAST does not recommend TZP STIC for certain Enterobacterales species that have a moderate to high likelihood of clinically significant AmpC production (E. cloacae, C. freundii, and K. aerogenes only) or for third-generation cephalosporin-non-susceptible (3GC-NS) Enterobacterales. USCAST recommends a TZP susceptibility breakpoint of ≤ 16/4 mg/L for third-generation cephalosporin-susceptible (3GC-S) Enterobacterales but only endorses the use of extended infusion TZP regimens for patients with infections due to these pathogens.

Multidrug Resistance And Susceptibility Profile of Outpatient Escherichia Coli Clinical Isolates

Background: To gain better understanding about the impact of antibiotic selection pressure on antimicrobial resistance (AMR) in Nigeria, it is important to conduct and review from time to time the susceptibility profile of clinically important bacteria including Escherichia coli. This study investigated the susceptibility and multidrug resistance profile of E. coli isolates from urine samples of patients who received outpatient’s medical services in Abakaliki. Methods: A total of 50 non-duplicate clinical isolates of E. coli from the microbiology laboratory section of a tertiary hospital in Abakaliki, Nigeria was recruited for this study. Susceptibility studies were determined using amoxicillin (20 µg), ceftazidime (30 µg), ciprofloxacin (5 µg), gentamicin (10 µg), nitrofurantoin (300 µg) and erythromycin acid (15 µg) by the modified Kirby–Bauer disk diffusion method. All susceptibility studies were carried out as per the guidelines of the Clinical Laboratory Standard Institute (CLSI). Multidrug resistance was evaluated by the multiple antibiotic resistance index (MARI) calculation. Results: The E. coli isolates showed reduced susceptibility to gentamicin (75%), ciprofloxacin (85%), nitrofurantoin (95%), amoxicillin (100%), erythromycin (100%) and ceftazidime (95%). A total of 12 E. coli isolates were multidrug resistant to clinically important antibiotics in the classes: cephalosporins, macrolides, aminoglycosides, fluoroquinolones, penicillins and nitrofurantoin. Conclusion: We report a high rate of antibiotic resistance of outpatients E. coli isolates which concurrently showed multidrug resistance to important antibiotic classes. These findings have clinical significance and provide a benchmark for future studies on the susceptibility pattern of clinical isolates in Nigeria. This preliminary study reiterates the need to reinvigorate antibiotic stewardship in our local hospitals so as to preserve the clinical efficacy of available antibiotics since it takes years for a new antibiotic to be developed.

Combating bacterial resistance to Meropenem by infusion strategy applied to septic burn patients with vasopressor requirements or acute kidney injury to achieve the target

Introduction: Faced with the growing challenge to the use of antimicrobials for the adequate and effective therapy of nosocomial infections, international health agencies have reinforced that combating bacterial resistance and preventing the development of multidrug-resistant (MDR) strains are urgent, since a significant increase based on minimum inhibitory concentration (MIC) for therapeutic agents were reported by the committee of hospitals infection. Meropenem, a carbapenem agent, is widely prescribed for therapy of septic shock caused by susceptible Gram-negative bacteria. In general, the prolonged 3-hrs-infusion has been widely applied in these patients over the past 10 years providing coverage only against susceptible Gram-negative pathogens (MIC 2 mg/L), extended also to intermediate susceptible strains up to MIC 4 mg/L, according to Clinical Laboratory Standard Institute (CLSI database). However, new strategies have been recommended to combat the development of resistance to pathogens isolated from cultures to increase the coverage of this carbapenem agent up to MIC 8 mg/L, to avoid mutant selection with death in ICU. Subject: Clinical protocol was carried out to investigate the efficacy & safety of meropenem at the dose regimen recommended 1g q8h by prolonged infusion, based on serum levels and on cultures monitoring of isolates. Aim of protocol was to assess pharmacodynamics (PD) based on changes of pharmacokinetics (PK), which could affect the coverage of meropenem in septic burns patients with increased or decreased renal function. Pharmacokinetic-pharmacodynamics (PK/PD) tools were applied to investigate efficacy & safety. Methods-clinical protocol: Forty-eight major septic burn patients with high variability on renal function in ICU were included. Cultures were collected before meropenem therapy starts; all of them had nosocomial infection caused by Gram-negative pathogens isolated. Patients undergoing meropenem therapy at the initial stage of septic shock from day-0 to day-8 (D0-D8) and at the late stage of septic shock from day 8 to day 14 (D-8 to D-14) were investigated according to dose requirements based on creatinine clearance, drug serum levels (TDM), and coverage up to MIC 8 mg/L, dose dependent on renal function. Results: Coverage occurred for all patients of both groups after the extended infusion against susceptible Gram-negative strains up to MIC 2 mg/L (minimum inhibitory concentration), and up to MIC 4 mg/L, strains of intermediate susceptibility, according to Clinical Laboratory Standards Institute (CLSI, database) of our hospital. It was demonstrated in patients with renal function augmented by vasopressors, the superiority on coverage by trice that occurred in 24/27 patients (89%) after 4 hrs.-infusion at TDM3 against strains MIC 8 mg/L by comparison with coverage registered in 12/39 patients (30%) after 3 hrs.-infusion at TDM2. On the other hand, meropenem dose regimen must be adjusted to 1g q24h in patients with AKI to guarantee effectiveness & safety in those patients. In addition, after continuous venovenous haemodialysis-filtration (CVVHDF) installed in those patients, meropenem PK/PD target was attained up to MIC 8 mg/L in patients with the empirical dose regimen recommended of 1g q8h, 3hrs.-infusion. Conclusion: Precision medicine guarantees meropenem serum levels combined with cultures monitoring; consequently, must be applied routinely to guarantee coverage against Gram-negative nosocomial pathogens susceptible including strains of intermediate susceptibility (MIC 4-8 mg/L) to avoid mutant selection. Therefore, effective, and safe antimicrobial therapy for patients in septic shock, combined with a continuous monitoring of inflammatory biomarkers, should guide clinical management to ensure cure with early ICU discharge.

Bullet-related bacterial wound infections among injured personnel at emergency site hospitals in Bahir Dar: prevalence, antimicrobial susceptibility and associated factors.

Bullet-related bacterial wound infection can be caused by high-velocity bullets and shrapnel injuries. In Ethiopia, significant injuries were reported that may cause severe wound infections, persistent systemic infections and may lead to amputation and mortality. The magnitude, antimicrobial susceptibility profiles, and factors associated with bacterial wound infections among patients with bullet-related injuries are not yet studied particularly at health facilities in Bahir Dar, Northwest Ethiopia. Therefore, this study was aimed to determine the prevalence, bacterial profiles, antimicrobial susceptibility profiles, and factors associated with bacterial infections among patients with bullet-related injuries at referral health facilities in Bahir Dar, Northwest Ethiopia. A Hospital-based cross-sectional study was conducted among patients with bullet-related injuries at three referral health facilities in Bahir Dar from May 25 to July 27, 2022. A total of 384 patients with bullet-related injuries were included in the study. Sociodemographic and clinical data were collected using a structured questionnaire. Wound swabs were collected aseptically and cultured on Blood and MacConkey agar following bacteriological standards. Biochemical tests were performed to differentiate bacteria for positive cultivation and antimicrobial susceptibility profiles of the isolates were done on Muller Hinton agar using the Kirby-Bauer disk diffusion technique according to the 2021 Clinical Laboratory Standard Institute (CLSI) guideline. The data were entered using Epi-Info version 7.3 and analyzed using SPSS version 25. Descriptive data were presented using frequency, percentages, figures, and charts. Logistic regression was carried out to identify factors associated with bacterial wound infections. P-value < 0.05 was considered statistically significant. The prevalence of bullet-related bacterial wound infection among three referral hospitals in Bahir Dar city was 54.7%. The most commonly isolated Gram-negative organism was Klebsiella spps 49 (23.3%) while among Gram-positive organism, Staphylococcus aureus 58 (27.6%) and coagulase-negative staphylococci (CONS) 18 (8.6%). Contamination, hospitalization and smoking habit were significantly associated with the presence of bullet-related bacterial wound infections. Over 97% multidrug resistant (MDR) bacterial isolates were identified and of theses, E. coli, Proteus species, Citrobactor, and Staphylococcus aureus were highly drug resistant. Increased prevalence of bullet-related bacterial wound infection was noticed in this study. S. aureus followed by Klebsiella species were most commonly isolated bacteria. High frequency of resistance to Ampicillin, Oxacillin, Cefepime, Ceftriaxone, Ceftazidime, Vancomycin, and Norfloxacin was observed. Therefore, proper handling of bullet injuries, prompt investigation of bacterial infections, monitoring of drug sensitivity patterns and antibiotic usage are critical.

Assessing Non-Laboratory Healthcare Professionals' Attitude towards the Importance of Patient Preparation for Laboratory Tests.

(1) Background: Various guidelines address patient preparation and its importance for venous blood sampling, such as the GP41 guideline issued by the Clinical Laboratory Standards Institute (CLSI) and the blood collection guidelines published by the World Health Organisation. Recommendations provided by national societies or international organisations in the field of radiology, such as The Contrast Media Safety Committee of the European Society of Urogenital Radiology, or in the field of laboratory medicine, such as the Working Group for Preanalytical Phase (WG-PRE) of the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) and the Latin American Working Group for Preanalytical Phase (WG-PRE-LATAM) of the Latin American Confederation of Clinical Biochemistry (COLABIOCLI), also guide this practice. There is a notable lack of understanding regarding the viewpoints held by non-laboratory healthcare professionals concerning the significance of patient preparation for laboratory testing and the impact of typical factors associated with patient preparation. This study endeavours to bridge this gap by assessing the attitude of non-laboratory healthcare professionals in Lithuania regarding these pivotal aspects. (2) Methods: A self-designed anonymous questionnaire was disseminated among 141 public healthcare institutions in Lithuania. The internal consistency of the questionnaire was evaluated by computing Cronbach's alpha. Descriptive statistics were utilised for the variables, while comparisons of attitude among groups were conducted using Mann-Whitney U (for two groups) or Kruskal-Wallis (for more than two groups) for categorical and discrete indicators. The Kruskal-Wallis post-hoc test was employed for pairwise comparisons. A significance level of p-Value < 0.05 was applied to establish statistical significance. (3) Results: A total of 158 respondents constituted two distinct groups of healthcare professionals: nurses and physicians. Most of the participants either agreed or strongly agreed that patient preparation could introduce bias into laboratory test results. Professionals with less than 20 years of work experience or those who attended training in patient preparation for sampling within a 5-year timeframe exhibited stronger agreement regarding different preanalytical factors in patient preparation and their impact on laboratory test results compared to their counterparts. (4) Conclusions: Non-laboratory healthcare professionals who participated in this survey consider proper patient preparation for laboratory testing to be a significant step towards obtaining accurate test results. They also recognize the commonly acknowledged preanalytical factors as important for ensuring reliable test results. However, attitudes towards the importance of several preanalytical factors vary depending on whether non-laboratory healthcare professionals have more or less than 20 years of work experience, as well as whether they have attended any training on this topic within the last five years or have never attended such training.

A comparative in vitro sensitivity study of “cefepime-tazobactam” and other antibiotics against Gram-negative isolates from intensive care unit

Objectives: The major health problem today includes the emergence of multidrug-resistant (MDR) bacteria, especially extended-spectrum β lactamase, carbapenemases, and Amp C-producing Gram-negative bacilli (GNB). Our study is aimed to recognize the in vitro susceptibility pattern of cefepime/tazobactam compared to other antibiotics used against GNB in an intensive care unit (ICU) setting. Materials and Methods: We conducted a prospective observational research comprising all GNB isolated from clinical samples of patients admitted to the ICU throughout the study period from January 2021 to December 2021. All of the isolates were analyzed using “ Matrix Assisted Laser Desorption/ionization - time of flight - Mass spectrometry assay (MALDI-TOF-MS)” for identification and the Kirby-Bauer disc diffusion technique to test for susceptibility. Cefepime-tazobactam was tested by E-test (Hi-Media, Mumbai) method. The minimum inhibitory concentrations (MIC) of cefepime (as in Clinical Laboratory Standards Institute, 2021) has been utilized to elucidate the sensitivity of cefepime-tazobactam, as no criteria for cefepime-tazobactam is available. Statistical Analysis: All statistical analysis was performed using the software program IBM Statistical Package for Social Sciences (SPSS) Statistics version 20.0, with P &lt; 0.05 considered statistically significant. Results: We included a total of 480 GNB isolated from blood, pus, body fluids, endotracheal aspirates (ETA), and sputum samples. The most common microorganism tested for susceptibility to cefepime-tazobactam was Klebsiella pneumoniae (182/480, 37.92%) followed by Acinetobacter baumannii (135/480, 28.12%), and Pseudomonas aeruginosa (94/480, 19.58%). K. pneumoniae and Enterobacter aerogenes were most resistant to all the antibiotics tested against them. K. pneumoniae was most resistant to meropenem (41/182, 22.53%), followed by imipenem (42/182, 23.08%) and cefoperazone-sulbactam (49/182, 26.92%) and was predominantly found susceptible to cefepime-tazobactam (122/182, 67.04%). Conclusions: Cefoperazone-tazobactam is a new “β-lactam/β-lactamase combination” found effective in the in vitro analysis of drug-resistant isolates of GNB.

PHENOTYPIC DETECTION AND ANTIMICROBIAL SUSCEPTIBILITY PROFILE OF EXTENDED SPECTRUM BETA LACTAMASE PRODUCING Escherichia coli FROM SUSPECTED CASES OF URINARY TRACT INFECTION IN KANO METROPOLIS, NIGERIA

Urinary tract infections (UTIs) caused by antimicrobial-resistant bacteria, especially ESBL-producing Escherichia coli can be life-threatening as therapeutic options available to treat infected patients are limited. Resistance due to ESBL-producing bacteria poses a peculiar challenge in treating infections because of its association with multidrug resistance. The aim of this study was thus to determine the susceptibility pattern and phenotypic detection of ESBL-producing E. coli from UTI patients. Two hundred and forty-six (246) E.coli isolates obtained from patients with suspected urinary tract infections were studied. The identity of the isolates was confirmed using standard biochemical tests. Antibiotic susceptibility testing was carried out using the Kirby-Bauer Disc Diffusion Technique. Screening for ESBL production was done using the Clinical Laboratory Standards Institute breakpoint. Suspected ESBL producers were subjected to confirmation using the Double Disc Synergy Test. Standard Discs of Augmentin (AMC 30µG Oxoid England), Ceftazidime (CAZ 30µG, Oxoid England) and Cefotaxime (CTX 30µG, Oxoid England) were used for the screening and confirmation. Multidrug-resistant E.coli were found to be 65.4%. Screening for ESBL production showed 67.1% suspected ESBLs producing E.coli. The Double Disc Synergy Test showed 22.4% confirmed ESBLs producing E.coli. Antimicrobial sensitivity of the ESBLs producing organisms showed 100% resistance to augmentin, ceftriaxone, ceftazidime, ciprofloxacin and cefotaxime while resistance to gentamicin was 91.1%, chloramphenicol 89.2%, nitrofurantoin 78.4%, and cotrimoxazole 94.6%. A 100% sensitivity to imipenem was also observed. ESBL-producing E.coli are present in Kano metropolis and are resistant to commonly prescribed antibiotics. We, therefore, suggest screening and confirmation for ESBL, to prevent treatment failure.

Microbial Contamination and Antibiotic Resistance in Food and Water: Assessing the Threat of Staphylococcus aureus in Lahore Metropolitan

Background: The research project in Lahore, Pakistan, seeks to detect S. aureus in drinking water, raw milk, and yogurt samples due to health concerns. S. aureus is a pathogenic bacterium with potential risks if present in food and water sources.Method: In this study, 300 samples of raw milk, yogurt, and drinking water were collected in Lahore. The presence of S. aureus was determined through morphological, microscopic, and biochemical methods. The biochemical analysis included testing for specific features of S. aureus. Disk diffusion technology was employed to assess the antimicrobial susceptibility of the isolates, following the recommendations of the Clinical Laboratory Standards Institute. Molecular confirmation was achieved through 16S rRNA sequence analysis using universal and specific primers.Results: The investigation uncovered that 6% of drinking water samples, 9% of yogurt samples and 58% of raw milk samples were tainted with S. aureus. These findings were further validated through 16S rRNA sequence analysis, affirming their reliability. S. aureus exhibited notable resistance rates, with 100% resistance to penicillin and 95% resistance to erythromycin. Conversely, resistance to ciprofloxacin and gentamicin was lower, at 10% and 5% each, indicating the potential efficacy of these antibiotics in treating S. aureus infections.Conclusion: The study emphasizes the risk of S. aureus infection from raw milk consumption in Lahore, Pakistan, due to inadequate sanitary practices. It stresses the necessity of implementing stricter measures in dairy production and water treatment to ensure public safety and reduce multidrug-resistant bacteria prevalence. Continuous monitoring and preventive actions are vital for safeguarding public health.Keywords: S. aureus; Antibiotic resistance; Food and water; Lahore, Pakistan; Sanitary measures

Antibiotic susceptibility profile of Pseudomonas species isolated from clinical specimens to access, watch and reserve drugs across various hospital settings at a tertiary care hospital of central India

Background and Objectives: Over the last decade, hospital-acquired infections, particularly in the critical care setting, have become more common, with Gram-negative bacterial infections having the highest prevalence. This study aims to determine the prevalence and antibiotic susceptibility pattern of Pseudomonas species to WHO’s, aware class of antibiotics, which are commonly prescribed across various ICU’s, medical and surgical wards of our tertiary care teaching hospital. Materials and Methods: This prospective study conducted from January 2021 to June 2022 at a tertiary care centre of cen- tral India identified Pseudomonas species from clinical samples using standard procedures and antimicrobial susceptibility testing performed as per Clinical Laboratory Standards Institute (CLSI) guidelines (M100; 32th Edition). Results: A total of 1490 non duplicate Pseudomonas species isolates were grown from 21,019 culture positive clinical sam- ples, of which 1247 were Pseudomonas aeruginosa. Out of these 1247 Pseudomonas aeruginosa 384 were MDR (30.7%). Pseudomonas aeruginosa were most commonly isolated from the pus samples (85%). ICU isolates were significantly more resistant to antibiotics than those from other units. P. aeruginosa strains from ICUs showed the highest rates of resistance to ceftazidime (93.9%). Reserve drug colistin showed good susceptibility (98.2%). All the 18 colistin resistant strains were found to be negative for plasmid mediated mcr-1,2,3 genes. Conclusion: The study shall help to generate and disseminate the data so that proper antibiotic policy can be made for judi- cious use of Access, Watch and Reserve antibiotics and antibiotic de-escalation plan can be put forth.

Molecular epidemiology of carbapenem-resistant gram-negative bacilli in Ecuador

IntroductionCarbapenem-resistant gram-negative bacilli are a worldwide concern because of high morbidity and mortality rates. Additionally, the increasing prevalence of these bacteria is dangerous. To investigate the extent of antimicrobial resistance and prioritize the utility of novel drugs, we evaluated the molecular characteristics and antimicrobial susceptibility profiles of carbapenem-resistant Enterobacterales, Pseudomonas aeruginosa and Acinetobacter baumannii in Ecuador in 2022.MethodsNinety-five clinical isolates of carbapenem non-susceptible gram-negative bacilli were collected from six hospitals in Ecuador. Carbapenem resistance was confirmed with meropenem disk diffusion assays following Clinical Laboratory Standard Institute guidelines. Carbapenemase production was tested using a modified carbapenemase inactivation method. Antimicrobial susceptibility was tested with a disk diffusion assay, the Vitek 2 System, and gradient diffusion strips. Broth microdilution assays were used to assess colistin susceptibility. All the isolates were screened for the blaKPC,blaNDM,blaOXA-48,blaVIM and blaIMP genes. In addition, A. baumannii isolates were screened for the blaOXA-23, blaOXA-58 and blaOXA-24/40 genes.ResultsCarbapenemase production was observed in 96.84% of the isolates. The blaKPC, blaNDM and blaOXA-48 genes were detected in Enterobacterales, with blaKPC being predominant. The blaVIM gene was detected in P. aeruginosa, and blaOXA-24/40 predominated in A. baumannii. Most of the isolates showed co-resistance to aminoglycosides, fluoroquinolones, and trimethoprim/sulfamethoxazole. Both ceftazidime/avibactam and meropenem/vaborbactam were active against carbapenem-resistant gram-negative bacilli that produce serin-carbapenemases.ConclusionThe epidemiology of carbapenem resistance in Ecuador is dominated by carbapenemase-producing K. pneumoniae harbouring blaKPC. Extensively drug resistant (XDR) P. aeruginosa and A. baumannii were identified, and their identification revealed the urgent need to implement strategies to reduce the dissemination of these strains.

Simultaneous determination of inflammatory factors SAA and LTF based on stable element labeling and inductively coupled plasma mass spectrometry to aid in the diagnosis of infection

ObjectiveThe clinical value of Serum amyloid A (SAA) and Lactoferrin (LTF) has received significant attention, but their detection methods are inadequate, which limits their application. This study aims to develop a dual detection method based on stable element labeling strategies and inductively coupled plasma mass spectrometry (ICP-MS) for SAA/LTF and to assess whether it can be widely used in clinical practice. MethodsA duplex immunoassay system based on sandwich method was constructed. After optimization, methodological evaluation was performed with the guidelines of Clinical Laboratory Standards Institute (CLSI). Finally, 131 plasma samples were collected to analyze whether the new method is suitable for clinical detection. ResultsThe LoB, LLoQ, ULoQ, and linear range of the assay were 1.09 ng/mL, 3 ng/mL, 1500 ng/mL, 3–1500 ng/mL for SAA and 0.85 ng/mL, 2 ng/mL, 1200 ng/mL, 2–1200 ng/mL for LTF respectively. The recovery rates were 95.01% to 106.26%, the intra-batch precision of low, intermediate, and high-level samples was <8%, and the inter-batch of them was <11%, the deviation of interference test results was less than±10%. The Area Under the Curve (AUC) was 0.9809 for SAA, 0.8599 for LTF, and 0.9986 for combination. ConclusionThe quantitative duplex immunoassay for SAA/LTF has high accuracy, good precision, and high specificity, which meets the clinical testing requirements and can be widely used in clinical practice.

Pathogenic Aspergillus Strains Identification and Antifungal Susceptibility Analysis of 452 Cases with Otomycosis in Jingzhou, China.

To study the distribution of pathogenic Aspergillus strains of otomycosis in central China and the identification of their antifungal sensitivity. We collected external ear canal secretions clinically diagnosed as otomycosis from April 2020 to January 2023 from the Department of Otolaryngology-Head and Neck Surgery in central China. The pathogenic Aspergillus strains were identified through morphological examination and sequencing. The antifungal sensitivity was performed using the broth microdilution method described in the Clinical Laboratory Standard Institute document M38-A3. In the 452 clinical strains isolated from the external ear canal, 284 were identified as Aspergillus terreus (62.83%), 92 as Aspergillus flavus (20.35%), 55 as Aspergillus niger (12.17%). In antifungal susceptibility tests the MIC of Aspergillus strains to bifonazole and clotrimazole was high,all the MIC90 is > 16 ug/mL. However, most Aspergillus isolates show moderate greatly against terbinafine, itraconazole and voriconazole. A. terreus is the most common pathogenic Aspergillus strain in otomycosis in central China. The selected topical antifungal drugs were bifonazole and clotrimazole; the drug resistance rate was approximately 30%. If the infection is persistent and requires systemic treatment, terbinafine and itraconazole can be used. The resistance of Aspergillus in otomycosis to voriconazole should be screened to avoid the systemic spread of infection in immunocompromised people and poor compliance with treatment. However, the pan-azole-resistant strain of Aspergillus should be monitored, particularly in high-risk patients with otomycosis.

Frequency of drug-resistant bacterial isolates among pregnant women with UTI in maternity and children’s hospital, Bisha, Saudi Arabia

Urinary tract infections (UTIs) are one of the most prevalent bacterial infections affecting humans, with a higher incidence among women. Pregnant women are at an increased risk of developing UTIs, which can have detrimental consequences for both the mother and fetus. UTIs can be caused by various bacteria, and the prevalence of drug-resistant UTIs in maternity and children’s hospitals is a cause for concern due to the potential for severe complications if left untreated. The primary objective of the current study was to determine the distribution of UTI-causing bacteria and investigate the antibiotic sensitivity patterns of isolated cultures obtained from pregnant women with UTIs at the Maternity and Children’s Hospital, Bisha, Saudi Arabia. This cross-sectional study was conducted from October 2021 to October 2023, involving the analysis of urine samples collected from 321 participants who acquired UTIs during pregnancy. Using biochemical tests and standard cultures, the urine samples were examined for pathogenic bacteria and their anti-microbial sensitivity patterns. The study analyzed susceptibility results according to the Clinical Laboratory Standards Institute guidelines (M100, 28th Edition, 2018). Bacterial strains demonstrating resistance to three or more antibiotics were classified as multidrug-resistant (MDR). This study revealed the distribution of UTI-causing bacteria to be as follows: Escherichia coli, 57.01%; Klebsiella pneumoniae, 24.61%; Pseudomonas aeruginosa, 4.36%; Proteus mirabilis and Enterobacter cloacae, 3.74%; Streptococcus agalactiae, 3.11%; Enterococcus faecalis, 2.18%; and Staphylococcus aureus, 1.24%. Antimicrobial susceptibility testing varied among gram-positive and gram-negative bacteria. Gentamicin demonstrated the highest sensitivity among both gram-positive and gram-negative bacteria; piperacillin-tazobactam was the second most effective drug against gram-negative bacteria. The bacterial isolates showed varying susceptibility to different antibiotics, with Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa being mainly sensitive to gentamicin, piperacillin-tazobactam, and ciprofloxacin, respectively. The strategies for reducing the risk of UTIs need to be improved to limit the spread of MDR bacteria. These strategies may include promoting hygienic practices and administering appropriate antibiotics to prevent the emergence and spread of drug-resistant bacteria. Further research is required to monitor the trends in antibiotic resistance among UTI-causing bacteria and develop effective strategies for managing this public health menace.

The antimicrobial effect of different vitamin D compounds on Streptococcus mutans and their impact on glycosyltransferase expression

ABSTRACT Background Streptococcus mutans is a virulent microorganism associated with dental caries. This in vitro study aimed to investigate the antimicrobial effects of Cholecalciferol (D3) and Doxercalciferol (D2), against S. mutans and on glycosyltransferase gene expression. Methods Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of D3 and D2 for S. mutans were determined according to the Clinical Laboratory Standards Institute guidelines. The effect of the compounds on environmental pH in 1% w/v and 5% w/v sucrose broth cultures after 24 hours were assessed colorimetrically. Additionally, their impact on glycosyltransferases gene expression (GtfB, GtfC, GtfD) in 5% w/v sucrose culture was evaluated using quantitative real-time PCR. Results The MBCs of D3 and D2 were 83 µg/ml and 166 µg/ml respectively. Both compounds were effective in preventing the local pH drop <5.5 at ≥166 µg/ml in sucrose supplemented cultures. However, the compounds did not inhibit pH drop at MIC values. Notably, D2 upregulated GtfD expression significantly (p < 0.05) and downregulated GtfB and GtfC. Conclusion Vitamin D2 and D3 inhibited S. mutans mediated pH drop in sucrose supplemented cultures and altered glycosyltransferase expression, suggesting potential therapeutic roles in dental caries prevention. Further research is needed to assess their full impact on S. mutans survival under environmental stresses.

Differences in the system accuracy acceptability of four types of blood glucose monitoring systems against five different standards

AbstractObjectiveThis study aimed to evaluate the system accuracy of four types of blood glucose monitoring systems (BGMSs) and explore the differences in the system accuracy acceptability of each BGMS against five different standards.MethodsThe glucose measurement values obtained from four types of BGMSs (Roche Accu‐Chek® Performa, Bayer Contour™ TS, Sinomedisite Glupad® H1 Plus, and Sinocare® Gold‐Accu) were evaluated against the reference values obtained from the biochemical analyzer of the central laboratory. The system accuracy acceptability of each BGMS was determined using the criteria specified in five standards, namely the International Organization for Standardization (ISO) 15197:2003, Clinical Laboratory Standards Institute (CLSI) POCT12‐A3, ISO 15197:2013, Chinese Society of Laboratory Medicine (CSLM) consensus, and US Food and Drug Administration (FDA) guidelines.ResultsFrom 2018 to 2022, 10,980 pairs of measurement values were obtained from 366 glucose meters of four types of BGMSs. Significant correlations were observed between the glucose measurement values from the BGMSs and the reference values from the biochemical analyzer of the central laboratory. The correlation coefficient r was 0.995 for Roche Accu‐Chek® Performa, 0.994 for Bayer Contour™ TS, 0.983 for Sinomedisite Glupad® H1 Plus, and 0.997 for Sinocare® Gold‐Accu. The acceptability criteria specified in ISO 15197:2003 were met by 100.00% (135/135) of the glucose meters of Roche Accu‐Chek® Performa, 100.00% (109/109) of Bayer Contour™ TS, 81.61% (71/87) of Sinomedisite Glupad® H1 Plus, and 100.00% (35/35) of Sinocare® Gold‐Accu. Whereas, the acceptability criteria specified in ISO 15197:2013 were met by 99.26% (134/135) of the glucose meters of Roche Accu‐Chek® Performa, 88.07% (96/109) of Bayer Contour™ TS, 58.62% (51/87) of Sinomedisite Glupad® H1 Plus, and 91.43% (32/35) of Sinocare® Gold‐Accu.ConclusionsAmong the four types of BGMSs evaluated, the glucose meters of Roche Accu‐Chek® Performa exhibited superior system accuracy. The system accuracy acceptability of each BGMS varied significantly against the acceptability criteria specified in the five different standards.

Fosfomycin susceptibility testing and resistance mechanisms in Enterobacterales in South Africa.

Fosfomycin treatment of urinary tract infections is increasingly attractive due to escalating antibiotic resistance rates among urinary pathogens. Standard antibiotic susceptibility testing methods perform poorly for fosfomycin as there is poor correlation between susceptibility results and clinical outcomes in urinary pathogens other than Escherichia coli. We evaluated the performance of fosfomycin susceptibility testing in E. coli and Klebsiella pneumoniae to determine whether fosfomycin susceptibility is associated with molecular resistance mechanisms. Forty-six each of E. coli and K. pneumoniae clinical isolates were obtained from a tertiary hospital in South Africa, from 01 June 2017 to 31 January 2018. Agar dilution, disk diffusion, and gradient diffusion were performed and interpreted using the Clinical Laboratory Standards Institute and European Committee on Antimicrobial Susceptibility Testing guidelines. Molecular resistance mechanisms were identified by whole genome sequence analysis. Disk diffusion and gradient diffusion were accurate alternatives for fosfomycin susceptibility testing in E. coli (98% categorical agreement), but not in K. pneumoniae (47% categorical agreement). All E. coli isolates contained at least one resistance mechanism, but only one isolate with a fosA gene was resistant. In K. pneumoniae, 63% (29/46) and 70% (32/46) of isolates were susceptible to fosfomycin, using Clinical Laboratory Standards Institute and European Committee on Antimicrobial Susceptibility Testing breakpoints, respectively, despite all isolates containing a fosA gene and a uhpT mutation. A better understanding of fosfomycin susceptibility and improved antibiotic susceptibility testing tools could improve diagnostic capability and clinical guidelines for fosfomycin treatment of urinary tract infections. This study highlights the importance of adhering to interpretive guidelines when performing antimicrobial susceptibility testing and the need for simplified, accurate and standardised susceptibility testing methodology and interpretation for fosfomycin in Enterobacterales organisms.