Laboratory Standards Institute Research Articles

Evaluation of Fosfomycin in-vitro susceptibility among gram negative isolates from urine culture in a tertiary care hospital in Lucknow

The rise of bacteria that are Multidrug- resistant or Extended Drug Resistant (MDR or XDR) and the lack of novel antibiotics have wreaked havoc on patient treatment options. Fosfomycin has just recently come to light because of the development of resistance to existing drugs. This study aims to evaluate the Fosfomycin susceptibility of Gram- negative isolates in vitro. A prospective study done in the Department of Microbiology, Integral Institute of Medical Sciences of Research, Lucknow, over a period of six months from April 2023 to September 2023. A total of 1328 urine samples were processed in microbiology lab and after identification of urinary isolates, antibiotic susceptibility testing was performed, and results were interpreted following the Clinical and Laboratory Standards Institute guidelines (CLSI). Fosfomycin sensitivity was tested by the Kirby-Bauer disc diffusion method. 353 of the 1328 processed urine samples showed a growth of pathogens. 184 (52.1%) of the isolates were Gram-negative, while 169 (47.8%) were Gram-positive. Fosfomycin (7%) and Nitrofurantoin (13%) showed lower rates of resistance among these isolates. Relatively higher rates of resistance were observed for Doripenem (17%), Meropenem (17%), Imipenem (18%), Amikacin (18%), Gentamicin (27.9%). Norfloxacin, Aztreonam, Cefepime, Ciprofloxacin and Levofloxacin and Cotrimoxazole showed a high resistance rate of 46.2%, 48.8%, 50%, 60.4%, 61% and 70% respectively. Fosfomycin's low resistance (7%) to the antibiotic indicates that it works well as a urinary antibiotic. Uropathogenic Enterobacteriaceae isolates exhibited an excellent level of in vitro susceptibility to Fosfomycin. These in vitro results highlight the unexplored possibilities of Fosfomycin as a superior therapeutic option for the treatment of UTIs, and it has a good chance of expanding into a safe and effective oral alternative treatment that can be used in inpatient as well as outpatient settings.

Nitrofurantoin susceptibility profile versus other antibiotics tested in uropathogens- a retrospective study from India

Introduction. Urinary Tract Infection (UTI) is one of the most common bacterial infections encountered by clinicians worldwide. The emergence of multidrug-resistant uropathogens necessitates a review of their susceptibility profiles. This study aims to assess the susceptibility trends of uropathogens to a panel of drugs, with special emphasis on Nitrofurantoin (NFT). Methods. A retrospective analysis was conducted on 2,099 mid-stream clean catch urine samples processed by standard microbiological methods. Clinical and Laboratory Standards Institute (CLSI) guidelines (2019) were followed. Statistical analysis was performed. Results. Out of all samples, 212 were culture positive. Escherichia coli (34.9%) and Enterococcus spp. (15.1%) were the most common Gram-negative and Gram-positive organisms, respectively. Gram-negative isolates were most susceptible to Colistin (97.38%), followed by NFT (69.35%). Gram-positive uropathogens were most sensitive to Linezolid (100%), followed by Vancomycin and NFT, each with 92.45% susceptibility. Conclusion. The increase in antibiotic resistance among various uropathogens underscores the need for surveillance data to inform the appropriate selection of antibiotics. Our study highlights that, among the panel of antibiotics tested, NFT appears to be a viable alternative for treating multidrug-resistant uropathogens.

Assessment of in vitro antimicrobial activity of ceftazidime-avibactam and phenotypic synergy testing with aztreonam against carbapenem resistant Gram-negative bacilli in a tertiary care hospital

Objectives: Ceftazidime avibactam (CZA) is a drug used against carbapenemase producing Gram-negative bacterial infections. Avibactam (AVI) is a non-beta-lactam-beta-lactamase inhibitor which has no action against metallo-β-lactamase (MBL) enzymes. This inadequacy is counteracted by combining CZA with aztreonam (ATM). The present study aims to denote the in vitro susceptibility pattern of the CZA and CZA-ATM combination in our area. Materials and Methods: In this study conducted prospectively from January to June 2023, the samples growing Enterobacterales and Pseudomonas aeruginosa were proceeded for carbapenemase detection by phenotypic testing for EDTA carbapenem inactivation method and modified carbapenem inactivation method. The minimum inhibitory concentration MIC of CZA was determined by E-strip and interpreted as per clinical and laboratory standard institute (CLSI) guidelines, while synergy testing of CZA and ATM was performed using ATM discs. Statistical Analysis: All data were entered in Microsoft Excel and analyzed for basic statistics. Results: The study included 150 carbapenem resistant organisms (131 Enterobactarales and 19 P. aeruginosa). Among these Enterobacterale strains, 72 (54.9%) were MBL producers. CZA resistance was detected in 69.3% of Klebsiella spp., 61.53% of Escherichia coli, and 50% of Serratia spp. Among Klebsiella spp. and E. coli, 88.9% and 65.2% of MBL isolates showed in vitro synergy to CZA-ATM. Conclusions: The study highlights a good in vitro sensitivity pattern of the CZA and ATM combination. However, we also highlight a growing percentage of non-synergistic interactions that need further genetic evaluation.

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.

Comparative study of antifungal susceptibility testing methods for clinical Candida albicans isolates

PurposeCandida albicans is the second most common cause of candidemia in Malaysia. The Clinical and Laboratory Standards Institute (CLSI) broth microdilution method is the gold standard for determining its minimum inhibitory concentration (MIC); however, it is laborious and time-consuming. This study was conducted to evaluate the usefulness of alternative methods, namely Sensititre YeastOne (SYO), VITEK 2 system, and E-test for determining the MIC of clinical C. albicans isolates. Materials and methodsThe susceptibilities of 95 C. albicans isolates were compared between SYO, VITEK 2 system, and E-test with CLSI broth microdilution method. The categorical agreement (CA), essential agreement (EA), very major errors (VME), major errors (ME) and minor errors (MiE) were calculated. ResultsOur finding showed the CA varied for SYO from 96.8% to 100%, while the EA ranged from 91.6% to 100%. The SYO method showed 1.1% of VME and ME, and up to 3.2% of MiE. Next, the CA and EA ranges for the VITEK 2 system were 97.8%–100% and 23.2%–100%, respectively. In the VITEK 2 technique, 1.1% of VME were found. For the E-test, the CA varied from 83.2% to 100% while the EA ranged from 64.2% to 98.9%. The E-test method showed 1.1% of VME and up to 16.8% of MiE. ConclusionsIn conclusion, SYO and VITEK 2 (except flucytosine) could be potential alternatives to the CLSI broth microdilution method in determining the MIC of C. albicans.

Susceptibility of Neisseria gonorrhoeae against a dual treatment antibiotics regimen in primary health centres in Surabaya, Indonesia.

There were 82.4 million new gonorrhoea cases worldwide in 2020. Dual treatment with ceftriaxone or cefixime and azithromycin or doxycycline is currently recommended for gonorrhoea in Indonesia. However, reduced susceptibility and resistance to cephalosporins and azithromycin are increasing. We evaluated the susceptibility pattern of Neisseria gonorrhoeae to cefixime, ceftriaxone, azithromycin and doxycycline. N. gonorrhoeae isolates were obtained from 19 male participants with clinically and laboratory-confirmed gonorrhoea. Antibiotic susceptibility testing was conducted by disc diffusion and interpreted according to Clinical and Laboratory Standards Institute and Centers for Disease Control and Prevention criteria. Reduced susceptibility or resistance was observed against doxycycline in 19 isolates (100%), cefixime in six (31.6%), ceftriaxone in three (15.8%) and azithromycin in zero (0%) isolates. A dual treatment regimen with ceftriaxone and azithromycin can still be recommended as first-line therapy for gonorrhoea in Indonesia. Antibiotic susceptibility surveillance of N. gonorrhoeae should be routinely conducted.

Retrospective study on the occurrence of Salmonella serotypes in veterinary specimens of Atlantic Canada (2012-2021).

This study aimed to summarize the frequency and the antimicrobial susceptibility profiles of the Salmonella serotypes identified from the specimens of companion animals, livestock, avian, wildlife and exotic species within Atlantic Canada. The retrospective electronic laboratory data of microbiological analyses of a selected subset of samples from 03 January 2012 to 29 December 2021 submitted from various animal species were retrieved. The frequency of Salmonella serotypes identified, and their antimicrobial susceptibility results obtained using the disk diffusion or broth method were analysed. The test results were interpreted according to the Clinical and Laboratory Standards Institute standard. The Salmonella serotypes were identified by slide agglutination (Kauffman-White-Le-Minor Scheme) and/or the Whole Genome Sequencing for the Salmonella in silico Serovar Typing Resource-based identification. Of the cases included in this study, 4.6% (n=154) had at least one Salmonella isolate, corresponding to 55 different serovars. Salmonella isolation was highest from exotic animal species (n=40, 1.20%), followed by porcine (n=26, 0.78%), and canine (n=23, 0.69%). Salmonella subsp. enterica serovar Typhimurium was predominant among exotic mammals, porcine and caprine samples, whereas S. Enteritidis was mostly identified in bovine and canine samples. S. Typhimurium of porcine origin was frequently resistant (>70.0%) to ampicillin. In contrast, S. Typhimurium isolates from porcine and caprine samples were susceptible (>70.0%) to florfenicol. S. Oranienburg from equine samples was susceptible to chloramphenicol, but frequently resistant (>90.0%) to azithromycin. In avian samples, S. Copenhagen was susceptible (>90.0%) to florfenicol, whereas Muenchen was frequently resistant (>90.0%) to florfenicol. S. subsp. diarizonae serovar IIIb:61:k:1,5 of ovine origin was resistant (50.0% isolates) to sulfadimethoxine. No significant changes were observed in the antibiotic resistance profiles across the study years. This report provides data for surveillance studies, distribution of Salmonella serotypes and their antimicrobial resistance among veterinary specimens of Atlantic Canada.

Specific reference interval for high-sensitivity cardiac troponin I among healthy children in Wuhan, China.

Troponin (Tn) is of an important biomarker for the diagnosis and prognosis of myocardial injury and for evaluating the severity of cardiac involvement due to other systemic diseases in children. Unfortunately, high-sensitivity cardiac troponin I (hs-cTnI) specific reference intervals (RIs) are extremely limited. This study aimed to establish a preliminary pediatric hs-cTnI RI for newborns, children, and adolescents in Wuhan, China. A total of 1,355 healthy participants (1 day to 19 years) were recruited from a cross-sectional study implemented in Wuhan Children's Hospital from September 2022 to August 2023. Serum hs-cTnI levels were detected via the Mindray automated chemiluminescence immunoassay analyzer (CL-6000i). Specific serum hs-cTnI RIs were established according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. The RIs were defined by the nonparametric median (P50), and 2.5th, 97.5th [P50 (P2.5-P97.5)] intervals. Of the 1,355 pediatric participants, serum hs-cTnI concentrations of 1,332 children were measured. The serum overall P50 and 95% interval range (P2.5-P97.5) of serum hs-cTnI was 0.41 (0.00, 44.31) ng/L. This was higher in males of 0.47 (0.00, 44.90) ng/L than in females of 0.36 (0.00, 44.17) ng/L (P<0.01). Age- and sex-specific differences in hs-cTnI levels were observed. The levels were highly variable in children under 1 year of age (especially in newborns), deriving a P50 (P2.5-P97.5) of 22.06 (1.04, 154.22) ng/L, and gradually narrowed and decreased with increasing age, with a markedly lower established P50 (P2.5-P97.5) of 0.36 (0.00, 2.16) ng/L. However, the levels began to increase slightly at the age of 9-12 years and reached a small peak at the age range of 15 to 18 years in males with 0.71 (0.03, 3.29) ng/L, while females were less affected by puberty. Sex- and age-specific RIs for hs-cTnI were established: 5 age-specific RIs in males, 1 day-1 month: 30.16 (8.67, 171.81) ng/L; >1-12 months: 13.20 (0.63, 61.91) ng/L; >1-15 years: 0.36 (0.00, 1.86) ng/L; >15-18 years: 0.71 (0.03, 3.29) ng/L; >18-19 years: 0.52 (0.00, 1.92) ng/L; and 4 age-specific RIs in females, 1 day-1 month: 43.93 (18.82, 146.38) ng/L; >1-12 months: 5.22 (0.92, 42.54) ng/L; >1-6 years: 0.54 (0.00, 2.74) ng/L; >6-19 years: 0.23 (0.00, 1.56) ng/L. This study preliminarily established age- and sex-specific serum hs-cTnI RIs using the Mindray CL-6000i system in healthy children in Wuhan, China.

Asymptomatic colonization of stray dogs and domestic cats with Trichophyton mentagrophytes II* in Northern Iran

BackgroundDespite changes in the epidemiology of dermatophyte infections, the incidence of fungal infections associated with Trichophyton species still remains high among dogs and cats. The objective of the present study was to isolate and characterize dermatophytes from dogs and cats in Iran. Method:From December 2022 to May 2023, skin and hair samples were collected from symptomatic and asymptomatic cats and dogs in Mazandaran, a northern province of Iran. The samples were then inoculated into Mycosel™ Agar. Dermatophyte isolates were identified by sequencing the internal transcribed spacer region. Antifungal susceptibility tests were conducted using the Clinical and Laboratory Standards Institute (CLSI-M38-A3). ResultOf the 250 samples collected (from 200 dogs and 50 cats), 20 (from 19 dogs and one cat) (8.0 %) were positive for dermatophyte growth. Based on sequence and phylogenetic analysis, all isolates belonged to T. mentagrophytes II*. Of these positive samples, 14 (70.0 %), 3 (15.0 %), 2 (10.0 %), and 1 (2.0 %) were isolated from asymptomatic stray dogs, symptomatic stray dogs, symptomatic domestic dogs, and symptomatic cats, respectively. Luliconazole and terbinafine displayed potent activity against all T. mentagrophytes isolates, with Minimum inhibitory concentration (MIC) values of 0.016 µg/ml. Miconazole and griseofulvin demonstrated higher MIC (1 and 8 µg/ml). ConclusionThe present study indicated that T. mentagrophytes II* asymptomatic carriage is frequent in stray dogs in Iran. The potential risk to public health needs to be evaluated However, T. mentagrophytes genotype VIII, considered as an endemic and emerging human pathogenic clone in several countries, was not detected during the present survey.

Comparison of Colistin Susceptibility via Two Different Methods in Gram-Negative Extensive Drug-Resistance Isolates from ICU Patients.

To compare the susceptibility of colistin by two methods in extensive drug-resistant (XDR) Gram-negative isolates from ICU patients. Cross-sectional comparative analysis. Place and Duration of the Study: Department of Microbiology, Combined Military Hospital Karachi, Pakistan, from August 2022 to February2023. A total of 100 clinical specimens received from the intensive care unit yielded growth of extensively drug-resistant gram-negative bacteria, which were evaluated for polymyxin E susceptibility. The agar dilution method was compared with the reference broth microdilution (BMD) method. Minimum inhibitory concentration (MIC) was noted for both methods. Comparison of the MIC method by agar dilution showed a 90% correlation with the reference method of broth microdilution. With MICs within the acceptable range of the clinical and laboratory standards institute (CLSI) recommendations, 89 isolates were susceptible to colistin, whereas only 11 remained resistant. Polymyxin E's MIC 50 and MIC 90 were determined to be 1 and 2 µg/ml, respectively, with 97% susceptibility. Agar dilution susceptibility method can be used for screening purposes for the susceptibility testing of polymyxin E. This method is reliable and can easily identify the heteroresistance. Extensively drug-resistant, Broth microdilution, Multidrug-resistant, Agar dilution, Minimum inhibitory concentration, Colony forming unit.

Inverted amino acids reduce the adhesion and biofilm biomass of early oral colonizers.

Early colonizers adhere to the dental surface and facilitate the initial adhesion of secondary colonizers to form oral biofilms, which may cause oral infections. This study aimed to determine the antimicrobial, anti-adhesion and antibiofilm potency of inverted amino acids on early colonizer streptococci and their mixed species. The following test strains were used: Streptococcus gordonii (American Type Culture Collection (ATCC) 35105); Streptococcus mitis (ATCC 49456); Streptococcus oralis (ATCC 10557); Streptococcus salivarius (ATCC 7073); and Streptococcus sanguinis (ATCC BAA-1455). The concentration-dependent antimicrobial potency of d-alanine (d-ala), d-arginine (d-arg), d-leucine (d-leu), d-methionine (d-met), and d-tryptophan (d-try) was determined using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method with AlamarBlue modification. The adhesion of primary colonizers in the presence of 25-mM d-amino acids (dAAs) was assessed using the colony forming unit (CFU) assay. The CFU assay was conducted on 24-h flow cell bacterial biofilm models after exposure to 25-mM inverted dAAs. No minimum inhibitory concentration (MIC) point was detected at any concentration tested. The minimum bactericidal concentration (MBC) point was not observed. The adhesion of S. mitis, S. oralis and mixed species was reduced by all tested dAAs. No adverse effects were observed on S. gordonii with any of the tested dAAs. The biofilm biomass of test strains under flow conditions was significantly reduced after a 5-min exposure to all tested dAAs at 25-mM concentration. D-amino acids did not inhibit bacterial growth and did not show bactericidal or bacteriostatic effects on test strains at any concentration tested (ranging from 6.25 mM to 100 mM). However, dAAs effectively inhibit the adhesion of early colonizers, thereby preventing the formation of oral biofilm.

Analytical validation of the Mindray CL1200i analyzer high sensitivity cardiac troponin I assay: MERITnI study.

This study performed an analytical validation study of the Mindray high-sensitivity cardiac troponin I (hs-cTnI) assay addressing limit of blank (LoB), limit of detection (LoD), precision, linearity, analytical specificity and sex-specific 99th percentile upper reference limits. LoB, LoD, precision, linearity and analytical specificity were studied according to Clinical and Laboratory Standards Institute. We used one reagent lot and one CL1200i analyzer. Skeletal troponin I and T, cardiac troponin T, troponin C, actin, tropomyosin, myosin light chain, myoglobin and creatine kinase (CK-MB) were studied for cross-reactivity. Interference with biotin was examined. Lithium heparin samples (one freeze thaw cycle) from healthy males and females were measured to determine the 99th percentiles by using the non-parametric method. Analyses were performed before and after excluding subjects with clinical conditions and/or increased surrogate biomarkers. The Mindray hs-cTnI assay met criteria to be considered as a hs-cTn assay. LoB and LoD was <0.1 ng/L and 0.1 ng/L, respectively. Repeatability had a coefficient of variation 1.2-3.8 %, and within-laboratory imprecision 1.7-5.0 %. The measuring interval ranged from 1.1 to 28,180 ng/L. The analytical specificity was clinically acceptable for the interferents studied. After exclusions, the 99th percentile URLs obtained were 10 ng/L overall, 5 ng/L for females and 12 ng/L for males. Analytical observations of the Mindray hs-cTnI assay demonstrated excellent LoB, LoD, precision, linearity and analytical specificity, that were in alignment with the manufacturer's claims and regulatory guidelines for hs-cTnI. The assay is suitable for clinical investigation for patient-oriented studies.

Photopolymerization and characterization of vinyl imidazole based allyl derivative polymers; Cr3+ and Cd2+ metal adsorption and antibacterial studies

AbstractA new type polymeric adsorbent, poly(allylphenol‐co‐hydroxyethyl methacrylate‐co‐vinyl imidazole) (PAHV), is synthesized in this study. 2‐Hydroxyethyl methacrylate is used as complementary monomers along with 1‐vinyl imidazole and allylphenol monomers. The photopolymerization method is preferred as a synthesis method and benzophenone is used as the photoinitiator. The effectiveness of the PAHV against bacterial species such as Escherichia coli and Staphylococcus aureus is investigated by the Clinical and Laboratory Standards Institute (CLSI) disk diffusion method. The inhibition areas of PA1H1V3 and PA1H1V1 derivatives against E. coli and S. aureus are measured as 25 mm ± 0.25 mm and 7 mm ± 0.1 mm; 20 mm ± 0.25 mm, and 5 mm ± 0.1 mm, respectively. Sorption efficiencies (%) at pH = 6 (selected optimum pH) for 100 μg/L Cd and Cr of the PA1H1V1, PA1H3V1, and PA1H1V3 derivatives are found to be 69.0 ± 2.7 and 58.3 ± 6.7, 66.8 ± 6.2 and 75.8 ± 5.5, and 97.2 ± 3.7 and 97.7 ± 3.2 (n = 3), respectively. Adsorption studies revealed that the PA1H1V3 polymer can be used as an alternative for the sorption of cadmium and chromium. The pseudo‐second‐order model and Langmuir isotherm model fits for both adsorption processes. The adsorption capacities obtained from the Langmuir isotherm model for chromium and cadmium sorption are 52.63 and 68.49 μg g−1, respectively.

Invasive group A streptococcal disease surveillance in Canada, 2021-2022.

Invasive group A streptococcal (iGAS, Streptococcus pyogenes) disease has been a nationally notifiable disease in Canada since 2000. This report summarizes the demographics, emm types, and antimicrobial resistance of iGAS isolates collected in Canada in 2021 and 2022. The Public Health Agency of Canada's National Microbiology Laboratory collaborates with provincial and territorial public health laboratories to conduct national surveillance of invasive S. pyogenes. Emm typing was performed using the Centers for Disease Control and Prevention emm sequencing protocol or extracted from whole-genome sequencing data. Antimicrobial susceptibilities were determined using Kirby-Bauer disk diffusion according to Clinical and Laboratory Standards Institute guidelines or predicted from whole-genome sequencing data based on the presence of resistance determinants. Overall, the incidence of iGAS disease in Canada was 5.56 cases per 100,000 population in 2021, decreasing from the peak of 8.6 cases per 100,000 population in 2018. A total of 2,630 iGAS isolates were collected during 2022, representing an increase from 2021 (n=2,179). In particular, there was a large increase in isolates collected from October to December 2022. The most predominant emm type overall in 2021 and 2022 was emm49, at 21.5% (n=468) and 16.9% (n=444), respectively, representing a significant increase in prevalence since 2018 (p<0.0001). The former most prevalent type, emm1, increased from 0.5% (n=10) in 2021 to 4.8% (n=125) in 2022; similarly, emm12 increased from 1.0% (n=22) in 2021 to 5.8% (n=151) in 2022. These two types together accounted for almost 25% of isolates collected in late 2022 (October to December). Antimicrobial resistance rates in 2021 and 2022 included: 14.9%/14.1% erythromycin resistance, 4.8%/3.0% clindamycin resistance, and <1% chloramphenicol resistance. The increase of iGAS isolates collected in Canada is an important public health concern. Continued surveillance of iGAS is critical to monitor expanding emm types and antimicrobial resistance patterns.

Effect of Incubation Time on Zone Size of Antimicrobials by Disk Diffusion Method for Pseudomonas Aeruginosa

Background: Pseudomonas aeruginosa is a prominent pathogen in healthcare settings, notorious for its rapid development of resistance to multiple antimicrobial agents. Effective susceptibility testing is critical for managing infections caused by this bacterium. This study investigates the impact of varying incubation times on the efficacy of the disk diffusion method. Objective: To evaluate the influence of incubation time on the zone sizes of antimicrobials against Pseudomonas aeruginosa using the disk diffusion method in a tertiary care setting. Methods: Conducted at the Microbiology Department of Combined Military Hospital, Lahore, from October 2022 to March 2023, this descriptive study included 71 clinical isolates of Pseudomonas aeruginosa. Samples were inoculated on Mueller Hinton Agar and incubated at 35°C ±2°C for 6, 10, and 24 hours. Antimicrobial susceptibility was tested using a panel of clinically relevant antibiotics in triplicate, with zone sizes interpreted according to Clinical and Laboratory Standards Institute guidelines. Results: Among the isolates, 59.15% were from males and 40.85% from females. The most affected age group was 15-60 years, comprising 59.52% of cases. Antimicrobial response varied with incubation times: Ceftazidime, Piperacillin-Tazobactam, and Cefepime showed increased zone sizes over time, while Tobramycin’s zones steadily enlarged. Colistin consistently produced the largest zones at all time points. Conclusion: The study highlights the significance of incubation time in disk diffusion testing for Pseudomonas aeruginosa. Adjusting incubation times can expedite results without incurring additional costs, enhancing the efficiency of antimicrobial susceptibility testing in clinical settings.

A Mini-Review of In Vitro Data for Candida Species, Including C. auris, Isolated during Clinical Trials of Three New Antifungals: Fosmanogepix, Ibrexafungerp, and Rezafungin.

This mini-review summarizes the clinical outcomes and antifungal susceptibility results, where available, for three new antifungals, including fosmanogepix, ibrexafungerp, and rezafungin, against Candida isolates cultured from patients in clinical trials. When reported, most of the data were generated by the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method or by both the CLSI and European Committee on Antimicrobial Susceptibility Testing (EUCAST) methodologies. For fosmanogepix, we summarize the in vitro data for C. auris isolates from 9 patients and for Candida spp. cultured from 20 patients in two clinical trials. Ibrexafungerp has also been evaluated in several clinical trials. From conference proceedings, a total of 176 Candida isolates were evaluated in the FURI and CARES studies, including 18 C. auris isolates (CARES study). However, MIC data are not available for all clinical isolates. Results from the ReSTORE rezafungin phase 3 clinical study also included in vitro results against Candida spp., but no patients with C. auris infections were included. In conclusion, this mini-review summarizes insights regarding clinical outcomes and the in vitro activity of three new antifungals against Candida spp. cultured from patients in clinical trials.

Antibacterial and Antibiofilm Potential of Bacterial Cellulose Hydrogel Containing Vancomycin against Multidrug-Resistant Staphylococcus aureus and Staphylococcus epidermidis.

The present study aimed to evaluate the in vitro antibacterial and antibiofilm activity of bacterial cellulose hydrogel produced by Zoogloea sp. (HYDROGEL) containing vancomycin (VAN) against bacterial strains that cause wound infections, such as multidrug-resistant (MDR) Staphylococcus aureus and Staphylococcus epidermidis. Initially, HYDROGEL was obtained from sugar cane molasses, and scanning electron microscopy (SEM) was performed to determine morphological characteristics. Then, VAN was incorporated into HYDROGEL (VAN-HYDROGEL). The antibacterial activity of VAN, HYDROGEL, and VAN-HYDROGEL was assessed using the broth microdilution method to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) against methicillin-sensitive S. aureus (MSSA) ATCC 25923, methicillin-resistant S. aureus (MRSA) ATCC 33591, S. epidermidis INCQS 00016 (ATCC 12228), five clinical isolates of MRSA, and nine clinical isolates of methicillin-resistant S. epidermidis, following the Clinical and Laboratory Standards Institute (CLSI) guidelines. Additionally, the antibacterial activity of VAN, HYDROGEL, and VAN-HYDROGEL was studied using the time-kill assay. Subsequently, the antibiofilm activity of VAN, HYDROGEL, and VAN-HYDROGEL was evaluated using crystal violet and Congo red methods, as well as SEM analysis. VAN and VAN-HYDROGEL showed bacteriostatic and bactericidal activity against MRSA and methicillin-resistant S. epidermidis strains. HYDROGEL did not show any antibacterial activity. Analysis of the time-kill assay indicated that HYDROGEL maintained the antibacterial efficacy of VAN, highlighting its efficiency as a promising carrier. Regarding antibiofilm activity, VAN and HYDROGEL inhibited biofilm formation but did not demonstrate biofilm eradication activity against methicillin-resistant S. aureus and S. epidermidis strains. However, it was observed that the biofilm eradication potential of VAN was enhanced after incorporation into HYDROGEL, a result also proven through images obtained by SEM. From the methods carried out in this study, it was possible to observe that HYDROGEL preserved the antibacterial activity of vancomycin, aside from exhibiting antibiofilm activity and enhancing the antibiofilm effect of VAN. In conclusion, this study demonstrated the potential of HYDROGEL as a candidate and/or vehicle for antibiotics against MDR bacteria that cause wound infections.

Determine the Prevalence of Pathogens and Their Antibiotics Sensitivity for Patients Suffering from Urinary Tract Infections in Babylon, Iraq

Background: Urinary tract infections (UTIs) are considered one of the most common infectious diseases, affecting most people of all age. Objectives: This study was conducted to determine the types of common bacteria causing UTIs and to measure the sensitivity of antibiotics to different bacteria. Materials and Methods: The current study included 208 of young group patients (aged 18 - 50 years) clinically suspected of having a UTIs. Out of 208 samples, the culture results showed that only 100 samples were positive for the presence of significant bacteria. Samples (midstream urine) were collected in a sterile tube, and significant results were shown for the isolated bacteria on selective media, identified by the VITEK-2 system. Then the Kirby-Bauer method was used to perform antibiotic susceptibility testing according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: The most common bacteria identified included; Escherichia coli (68.3%), Staphylococcus aureus (7.8%), Enterococcus faecalis (6.7%), Klebsiella pneumoniae (5.8%), (3.8%) for both Pseudomonas aeruginosa and Staphylococcus saprophyticus, While Streptococcus agalactiae accounted for (1.9%), Proteus mirabillus and Serratia marcescens (0.9%) for all of them. Moreover, there was mixed bacterial growth. Results revealed E. coli was sensitive to Imipenem, Ciprofloxacin and resistant to Tobramycin and Amikacin. Meanwhile, K. pneumoniae was completely sensitive to Imipenem and Ciprofloxacin with utterly resistant to Piperacillin. P. aeruginosae was sensitive to Imipenem, Meropenem and resistant to Azithromycin, Tobramycin, Ceftriaxone and levofloxacin. Whereas, S.aureus was sensitive to Ciprofloxacin and Levofloxacin and resistant to Trimethoprim and Azithromycin, E. faecalis was sensitive to Vancomycin with resistant to Azithromycin and Ciprofloxacin. Conclusions: The study concluded that females are more susceptible to UTIs than to males. In addition, females with UTIs tend to be younger than males. E. coli is the most common isolate among bacteria that cause UTIs. Study revealed that Imipenem remains the most potent treatment for inhibiting most types of bacteria causing UTIs, in addition, Meropenem, Ciprofloxacin, and Levofloxacin can be considered a potential treatment option.

Gram Positive Cocci Associated Urinary Tract Infections, their Prevalence and Antibiotic Susceptibility Patterns

Background: Urinary tract infections (UTIs) are the third most common type of infection in humans globally. Gram-positive bacteria are said to be responsible for ten percent of urinary tract (UTI) infections. The study's goal was to profile gram-positive cocci-associated UTIs and their antibiogram, as they were observed at LASUTH. Methods: This was a retrospective assessment of the Medical Microbiology Laboratory records of the LASUTH to review the in vitro antibiotic susceptibility patterns of gram-positive urinary bacterial isolates between April 2020 and March 2021. The bacteria were isolated and identified from routine urine samples using standard bacteriological methods and the API. In vitro antibiotic susceptibility test (AST) was routinely performed by the modified Kirby-Bauer disk diffusion test and susceptibility breakpoints were determined using the Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: 2,253 urine samples were processed in the medical microbiology laboratory over the one year and 662 (29.4%) samples yielded Positive cultures. Of the 662 isolates, 494 (74.6%) were gram-negative bacteria. 164 (24.8%) were gram-positive cocci while 4 (0.6%) were gram positive rod. Among the gram-positive cocci’s isolated Enterococcus faecalis had the highest frequency 58 (35.4%). Aminoglycosides (Gentamycin and Amikacin) and Linezolid antibiotics were found to be the most effective drugs against gram-positive cocci bacteria except Enterococcus spp. For empirical treatment of Enterococcus spp in our facility Fosfomycin and Tigecycline are the best options, while for Streptococcus agalactiae associated UTI, Amikacin, Cefuroxime, Linezolid, and levofloxacin can be used for empirical treatment. Conclusion: The prevalence rate of gram-positive cocci associated UTI in this study was 7.3% (164/2253). The emergence of drug resistance in these pathogens to commonly used antibiotics is a thing of concern. Therefore, efficient antimicrobial stewardship programmes must be in place.

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.