Clinical And Laboratory Standards Institute Research Articles

Staphylococcus aureus Among Athletes In Zakho City, Kurdistan Region, Iraq: Nasal Carriage Rate, Risk Factors, and Antibiotic Sensitivity Profile

Background and aims: Staphylococcus aureus is a leading cause of infectious diseases and responsible for outbreaks among athletes’ team. The aims of this study were to determine the prevalence rate of S. aureus among athletes, and evaluate the antibiotic resistance and risk factors associated with S. aureus isolates.
 Materials and methods: We performed a cross-sectional study to determine the S. aureus nasal carriage rate among athletes practicing different sports. Swabs were collected from the anterior nares of 510 athletes aged between 14-55 years. Conventional bacteriological tests were used for the identification of the S. aureus isolates. The antibiotic sensitivity test was performed according to the Clinical and Laboratory Standards Institute (CLSI).
 Results:Out of recruited samples, S. aureus carriage rate among athletes was 156 (30.2%). The highest infection rate was reported among boxing athletes 8/24(33.33%) and gym 80/245 (32.65%). S. aureus colonization was significantly higher among the athletes who had low body mass index (p=0.001), longer duration of training/day (p=0.001) and higher number of training session /week (p=0.012). S. aureus carriage was significantly higher among male athletes 119 (77.27%) than female athletes 35 (22.73%) (p=0.002). The oxacillin resistance rate was estimated at 26.61%. S. aureus isolates were highly susceptible to rifampicin, gentamycin and fusidic acid.
 Conclusion: Nasal carriage of S. aureus is relatively high and this bacterial was predominant among male athletes and a relevant resistance to antibiotics used for treatment of S. aureus infection. It is recommended that the prevention control practices be implemented to reduce nasal colonization, and risk factors associated with S. aureus among athletes. Further studies on S. aureus carriage should include throat sampling among athletes

THE ANTIBIOTICS SENSITIVITY TEST ON STAPHYLOCOCCUS AND STREPTOCOCCUS FROM CHRONIC APICAL ABSCESS

Background: Prophylactic antibiotics are required as part of root canal therapy for patient with chronic apical abscess. Streptococcus and Staphylococcus are the most common bacteria found in root canals with chronic apical abscess. Resistance to amoxicillin, clindamycin and vancomycin has been increasing year after year, necessitating the use of a sensitivity test. The goal of this research was to determine the sensitivity of Streptococcus and Staphylococcus from root canals with chronic apical abscess to amoxicillin, clindamycin, and vancomycin to make scientific antibiotic selections. Method: Six isolates of Staphylococcus and one Streptococcus from root canals with chronic apical abscess were identified by Remel RapID and tested to 10 g amoxicillin, 2 g clindamycin, and 30 g vancomycin using Kirby-Bauer disk-diffusion sensitivity test. The diameter inhibition zone was measured and interpreted according to the CLSI (Clinical and Laboratory Standards Institute) standard. Result: Three of six Staphylococcus are resistant, one of six are intermediate, and two are sensitive to amoxicillin. While the Streptococcus is sensitive to amoxicillin. In contrast, all Staphylococcus and the Streptococcus are resistant to clindamycin. Whilst four of six Staphylococcus are resistant, two are intermediate, and the Streptococcus is resistant to vancomycin. Conclusion: Staphylococcus sensitivity to amoxicillin and vancomycin are diverse even though resistant to clindamycin. In comparison, the Streptococcus sensitivity to clindamycin and vancomycin is resistant but sensitive to amoxicillin.

Biomarker enrichment medium: A defined medium for metabolomic analysis of microbial pathogens.

Microbes have diverse metabolic capabilities and differences in these phenotypes are critical for differentiating strains, species, and broader taxa of microorganisms. Recent advances in liquid chromatography-mass spectrometry (LC-MS) allow researchers to track the complex combinations of molecules that are taken up by each cell type and to quantify the rates that individual metabolites enter or exit the cells. This metabolomics-based approach allows complex metabolic phenotypes to be captured in a single assay, enables computational models of microbial metabolism to be constructed, and can serve as a diagnostic approach for clinical microbiology. Unfortunately, metabolic phenotypes are directly affected by the molecular composition of the culture medium and many traditional media are subject to molecular-level heterogeneity. Herein, we show that commercially sourced Mueller Hinton (MH) medium, a Clinical and Laboratory Standards Institute (CLSI) approved medium for clinical microbiology, has significant lot-to-lot and supplier-to-supplier variability in the concentrations of individual nutrients. We show that this variability does not affect microbial growth rates but does affect the metabolic phenotypes observed in vitro—including metabolic phenotypes that distinguish six common pathogens. To address this, we used a combination of isotope-labeling, substrate exclusion, and nutritional supplementation experiments using Roswell Park Memorial Institute (RPMI) medium to identify the specific nutrients used by the microbes to produce diagnostic biomarkers, and to formulate a Biomarker Enrichment Medium (BEM) as an alternative to complex undefined media for metabolomics research, clinical diagnostics, antibiotic susceptibility testing, and other applications where the analysis of stable microbial metabolic phenotypes is important.

Antimicrobial Resistance Pattern of Escherichia coli Isolates from Small Scale Dairy Cattle in Dar es Salaam, Tanzania.

Simple SummaryDearth of information on antimicrobial resistance (AMR) in small-scale dairy cattle in Dar es Salaam, the commercial city of Tanzania, prompted us to conduct this study. The objective was to determine the different levels of resistance phenotypical patterns among Escherichia coli (E. coli) isolates from rectal swabs of apparently healthy cattle. Antimicrobial resistance occurs when microorganisms develop the ability to tolerate antimicrobial concentrations to which they were initially susceptible. It is a phenomenon of global concern, which is on the rise due to antimicrobial use in food-producing animals. In dairy farms, cattle carry high levels of AMR Escherichia coli (E. coli), and may act as a potential reservoir. The study revealed that resistance to ampicillin, cefotaxime, tetracycline and trimethoprim/sulfamethoxazole was the most frequent. Resistance to nalidixic acid, ciprofloxacin, chloramphenicol, and gentamycin was also observed among the E. coli isolates, but with lower percentages. E. coli resistant to third generation cephalosporins was also detected. The results of the current study give an insight into the status of antimicrobial resistance and multidrug resistance in small-scale dairy cattle in Dar es Salaam, Tanzania. The findings call for further research, prudent antimicrobial use, and surveillance initiatives.In Tanzania, information on antimicrobial resistance in small-scale dairy cattle is scarce. This cross-sectional study was conducted to determine the different levels and pattern of antimicrobial resistance (AMR), in 121 Escherichia coli isolated from rectal swab of 201 apparently healthy small-scale dairy cattle in Dar es Salaam, Tanzania. Isolation and identification of E. coli were carried out using enrichment media, selective media, and biochemical tests. Antimicrobial susceptibility testing was carried out using the Kirby–Bauer disk diffusion method on Mueller-Hinton agar (Merck), according to the recommendations of Clinical and Laboratory Standards Institute (CLSI). Resistance was tested against ampicillin, gentamicin, chloramphenicol, trimethoprim-sulfamethoxazole, tetracycline, nalidixic acid, ciprofloxacin and cefotaxime. Resistance to almost all antimicrobial agents was observed. The agents to which resistance was demonstrated most frequently were ampicillin (96.7%), cefotaxime (95.0%), tetracycline (50.4%), trimethoprim-sulfamethoxazole (42.1%) and nalidixic acid (33.1%). In this case, 20 extended-spectrum beta-lactamases (ESBLs) producing E. coli were identified. 74.4% (90/121) of the isolates were Multidrug resistant (MDR), ranging from a combination of three to 8 different classes. The most frequently observed phenotypes were AMP-SXT-CTX with a prevalence of 12.4%, followed by the combination AMP-CTX with 10.7% and TE-AMP-CTX and NA + TE + AMP + CTX with 8.3% each. The high prevalence and wide range of AMR calls for prudent antimicrobial use.

Species distribution and antifungal susceptibility of isolates from cases of health-care associated infections

Fungi have emerged as an important cause of health-care associated infections (HCAI) in last few decades. spp. is the most common cause of invasive fungal infections (IFI) in hospitalized individuals. The present study was conducted in a tertiary care teaching hospital with an aim to study species distribution and antifungal susceptibility pattern of isolates from cases of HCAI. isolates from cases of HCAI from medical intensive care unit were identified up to species level. Antifungal susceptibility testing of isolate was done by Clinical and Laboratory Standard Institute (CLSI) broth microdilution (BMD) method. The rate of CA-UTI due spp. was 0.3 per 1000 catheter associated days. The rate of catheter related BSI was 0.9 per 1000 catheter associated days. Predominance of non spp. over was noted. Fluconazole resistance was significantly high in NAC spp. compared to .

Prenylated Flavonoids in Topical Infections and Wound Healing.

The review presents prenylated flavonoids as potential therapeutic agents for the treatment of topical skin infections and wounds, as they can restore the balance in the wound microenvironment. A thorough two-stage search of scientific papers published between 2000 and 2022 was conducted, with independent assessment of results by two reviewers. The main criteria were an MIC (minimum inhibitory concentration) of up to 32 µg/mL, a microdilution/macrodilution broth method according to CLSI (Clinical and Laboratory Standards Institute) or EUCAST (European Committee on Antimicrobial Susceptibility Testing), pathogens responsible for skin infections, and additional antioxidant, anti-inflammatory, and low cytotoxic effects. A total of 127 structurally diverse flavonoids showed promising antimicrobial activity against pathogens affecting wound healing, predominantly Staphylococcus aureus strains, but only artocarpin, diplacone, isobavachalcone, licochalcone A, sophoraflavanone G, and xanthohumol showed multiple activity, including antimicrobial, antioxidant, and anti-inflammatory along with low cytotoxicity important for wound healing. Although prenylated flavonoids appear to be promising in wound therapy of humans, and also animals, their activity was measured only in vitro and in vivo. Future studies are, therefore, needed to establish rational dosing according to MIC and MBC (minimum bactericidal concentration) values, test potential toxicity to human cells, measure healing kinetics, and consider formulation in smart drug release systems and/or delivery technologies to increase their bioavailability.

Epidemiologic and Antifungal Susceptibility Profile of Candiduria Among Patients Hospitalized in The Nephrology and Intensive Care Unit Wards, Tehran, Iran

Background: One of the most prevalent infections in hospitalized patients is candiduria. As the prevalence of this infection is increasing, new epidemiologic and therapeutic data can be used as a guide for the management of patients. Objectives: This research aimed to determine the epidemiological and antifungal susceptibility profile of candiduria. Methods: A total of 104 patients admitted to the nephrology and ICU wards of Bu Ali and Labbafinezhad hospitals in Tehran, Iran, were studied in this cross-sectional investigation. Urine samples were examined using direct smear, culture, and PCR-sequencing techniques. The culture plates were subjected to colony count. The clinical and laboratory standards institute (CLSI) document M27 4th ed was used to assess susceptibility to amphotericin B, itraconazole, caspofungin, and fluconazole. Results: Out of 104 patients, 26 (25%) were diagnosed with candiduria. Most patients were between the ages of 64 - 79 years (n = 9, 34.61%) and female (n = 17, 23.94%). Stroke and urinary catheterization were the most common underlying diseases. Candida glabrata (n = 10, 38.64%) was the most common cause of candiduria. Caspofungin and amphotericin B were the most effective antifungal medicines. Conclusions: Candida glabrata has been identified as the most common cause of candiduria. Due to the increasing antifungal resistance in this species, proper treatment of patients is a crucial concern. Caspofungin exhibited potent antifungal activity against all tested isolates. Still, regardless of its favorable in vitro activity, due to its poor glomerular filtration or tubular secretion in vivo, it has sub-therapeutic antifungal concentrations in the urine.

Aryloxy Alkyl Theophylline Derivatives as Antifungal Agents: Design, Synthesis, Biological Evaluation and Computational Studies

AbstractInfectious diseases are still one of the leading causes of death and disability in human society. Synthetic antimicrobial agents have recently emerged as promising candidates against drug‐resistant pathogens. Here we described an efficient procedure for synthesis of aryloxyalkyl theophylline analouges as novel antimicrobial agents. Fourtheen new compounds were synthesized (5 a–5 n) and their chemical structures were approved by different spectroscopic methods. The synthesized compounds were screened for their antimicrobial activities by broth micro dilution method as recommended by Clinical and Laboratory Standards Institute (CLSI). Molecular docking studies were also performed to forecast their binding modes against cytochrome P450 lanosterol 14α‐demethylase as a main target. The results represented appropriate correlation between molecular docking and antimicrobial activity of the compounds. Based on biological results and in silico ADMET (absorption, distribution, metabolism, excretion, and toxicity) predictions, compound 5 g can be considered as an ideal antimicrobial agent for the future studies.

Prevalence of ESBL genes in Klebsiella pneumoniae from individuals with community-acquired urinary tract infection in rural communities of Enugu State, Nigeria

Background: The emergence and spread of extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae is now a major challenge in treating urinary tract infections. This study was conducted to determine the Prevalence of ESBL genes in Klebsiella pneumoniae and the influence of these genes on the antimicrobial susceptibility patterns of the isolates, obtained from community acquired urinary tract infection in Enugu state rural communities. Method: A total of 735 clean catch mid-stream urine samples were collected from February, 2021 to June, 2021. The urine samples were cultured and Klebsiella pneumoniae were identified morphologically, biochemically, and then typed down, using PCR, Gel electrophoresis, and Sanger Sequencing by Genewiz. Antibiotic susceptibility testing was done by modified Kirby-Bauer disc diffusion method and interpretation was done following Clinical and Laboratory Standard Institute (CLSI) guidelines. ESBL screening was done by the phenotypic method, using the standard disk diffusion method, whereas the phenotypic confirmation of ESBL producers was done by the double-disk synergy method, and interpreted according to CLSI guidelines. Multiplex PCR was used to detect the genes for SHV and CTX-M while conventional linear PCR was done for TEM and blas GES type ESBL genes. Results: A total of 77 isolates were identified as Klebsiella pneumoniae, and the prevalence of positive ESBL in them were 10(12.9%). Of the 77 isolates that were tested for antibiogram, 29 isolates were multidrug-resistance (MDR). Out of the MDR isolates, 10 were ESBL positive, whereas 19 were not. Of this 29 MDR isolates, 6 were extensively-drug resistant (XDR). Of the 6 XDR isolates, 3 do not possess ESBL enzymes, whereas 3 of them do. Age range of 31-40 contributed the highest prevalence of ESBL genes (60%), whereas age range of 10-20, 21-30, and 51-70 did not produce any ESBL gene. bla TEM gene was the most prevalent ESBL resistant genes with a prevalence of 10 (100%), followed by SHV 9(90%), whereas bla GES gene and bla CTX-M have the least prevalence of 4 (40%) each. Conclusion: Higher prevalence of MDR, XDR, and ESBL-producing Klebsiella pneumoniae were observed, thus the need for public health intervention for effective prevention and control of antimicrobial resistance, and proper treatment of UTIs.

Focused Commentary; About Revision of CLSI Antimicrobial Breakpoints, 2018-2021

In recent years, antimicrobial resistance has been on the rise and infectious disease specialists and other clinicians face several challenges when treating patients with antimicrobial resistant infections. Clinical and Laboratory Standards Institute (CLSI) annually publishes guidelines for antimicrobial resistance tests, including revised antimicrobial breakpoints, because of the rise in antimicrobial resistance and changes to nomenclature owing to advances in whole genome sequencing technology. However, many laboratories use historical guidelines and do not follow the revised breakpoints. Moreover, the current breakpoints have limitations. This study evaluated the changes in antimicrobial breakpoints over the last 4 years, from 2018 to 2021. Here, I describe the microbiological and clinical background of the CLSI breakpoint revision and evaluate the advantages and limitations of new breakpoints with a review of large study data. In addition, I reviewed problems associated with each antimicrobial breakpoint and made suggestions for how they might be improved, for example, increasing or decreasing the minimum inhibitory concentration (MIC) or zone diameter, deleting or adding an S, I, or R category, introducing new concepts (such as susceptible-dose dependent (SDD)), and requesting more evaluation methods. Conclusions; CLSI annually publishes guidelines for antimicrobial resistance tests. I reviewed problems associated with each antimicrobial breakpoint for last 4 years, and made suggestions for how they might be improved.

Development of Diagnostic Capabilities for Complications of Bacterial Infection in Diabetic Patients.

OBJECTIVE: Our objective was to assess the pattern of urine infections, the most common pathogen, and their susceptibility pattern to antibiotics among Saudi diabetic patients. METHODS: We performed a year-long cross-sectional study from January 2018 to January 2019 at KAAU Hospital in Riyadh, KSA. We cultured the urine specimens obtained from diabetic patients based on optimal aerobic and anaerobic microbiological methods. By adopting standard microbiological methods, we identified the bacterial isolates. We also followed the guidelines of the Clinical and Laboratory Standards Institute (CLSI) to do antibiotic susceptibility testing. RESULTS: A total of 100 isolates were evaluated, and a total of 22 organisms were isolated. The majority were multidrug-resistant organisms. Streptococcus haemolyticus was the most frequent organism and rated (15%). It was followed by Staphylococcus hominis (11%), Pseudomonas aeruginosa (9%), Enterococcus faecalis (9%), Enterococcus fiseum (7%), Escherichia coli (7%), Staphylococcus aureus (7%), Staphylococcus lantus (5%) and Klebsiella pneumoniae (5%). We also found multi-microbial infections. Most of the organisms were susceptible to tigecycline, gentamycin, and nitrofurantoin, rating (88%), (84%) and (78%), respectively. CONCLUSIONS: Our study revealed that a wide range of pathogens affects the diabetes patients. Staphylococcus haemolyticus is the most prevalent pathogen. We observed considerable antimicrobial resistance. Tigecycline had a wide sensitivity spectrum and was effective against most of the bacteria. Thus, it can be used as an empirical antibiotic.

Bacterial sensitivity pattern to antibiotics in acne vulgaris at Universitas Sumatera Utara Hospital Medan, Indonesia in 2019

Background: Acne vulgaris (AV) is a chronic inflammatory disorder of the pilosebaceous unit. Antibiotics play essential roles in the treatment of AV because of their antibacterial and anti-inflammatory properties. With the extensive use of antibiotics, antibiotic resistance patterns in AV lesions should be determined to ensure safe and appropriate administration of antibiotics for the treatment of AV. Methods: This cross-sectional study involved 80 specimens from AV lesions. Each specimen was cultured and underwent susceptibility tests to azithromycin, erythromycin, clindamycin, doxycycline, minocycline, tetracycline, levofloxacin and ciprofloxacin using disc diffusion methods that met Clinical and Laboratory Standard Institute (CLSI) standard. Results: From a total 97 bacterial colonies growth from 80 specimens, 12 species were identified, namely Cutibacterium acnes, Staphylococcus epidermidis, Staphylococcus hominis, Staphylococcus aureus, Staphyococcys haemolyticus, Leuconostoc mesenteroides, Micrococcus luteus, Kocuria varians, Staphylococcus vitulinus, Staphylococcus cohnii, Staphylococcus arlettae and Dermacoccus nishinomyaensis. Antibiotic with highest bacterial sensitivity rate was minocycline, followed by levofloxacin, ciprofloxacin, doxycycline, tetracycline, azithromycin, erythromycin, and clindamycin. Most of the species were intermediately sensitive to azithromycin, clindamycin, erythromycin, doxycycline, tetracycline, ciprofloxacin, and levofloxacin. Antibiotic with highest bacterial resistance rate was erythromycin, followed by clindamycin, azithromycin, tetracycline, doxycycline, ciprofloxacin, levofloxacin and minocycline. Conclusions: In cases of acne vulgaris, minocycline and levofloxacin were the two antibiotics with the highest bacterial sensitivity, while erythromycin and clindamycin were the two antibiotics with the highest bacterial resistance in AV lesions. Keywords: acne vulgaris, antibiotics, bacterial sensitivity

In vitro activity of 23 antifungal drugs against 54 clinical and environmental Aspergillus oryzae isolates

The treatment of invasive aspergillosis caused by cryptic species remains a challenge due to the lack of randomised clinical trials and investigation of the efficacy and safety of different therapeutic strategies. We aimed to evaluate the in vitro activity of 23 conventional and new antifungal drugs against 54 clinical and environmental Aspergillus oryzae isolates by using the Clinical and Laboratory Standards Institute (CLSI) standard M38-A3. The lowest geometric mean MIC values were found for luliconazole and lanoconazole (0.001 μg/ml), followed by anidulafungin (0.104 μg/ml), posaconazole (0.15 μg/ml), itraconazole (0.37 μg/ml), efinaconazole (0.5μg/ml), voriconazole (0.51 μg/ml), tavaborole (0.72 μg/ml), and amphotericin B (0.79 μg/ml). In contrast, ketoconazole, terbinafine, econazole, tioconazole, ravuconazole, miconazole, nystatin, clotrimazole, griseofulvin, sertaconazole, natamycin, tolnaftate, and fluconazole had no or low activity. Further studies are required to determine how well this in vitro activity translates into in vivo efficacy.

Prevalence and Antimicrobial Sensitivity Pattern of Gram Negative Rods in Blood Cultures: A Tertiary Care Hospital Study

Aim: Prevalence and antimicrobial susceptibility pattern of gram negative rods in blood cultures. Methods: Cross-sectional study performed in Pathology section, Pak Red Crescent Teaching hospital, Lahore for one year i.e. 01-11-2019 to 31-12-2020. After approval from ethical committee, 1100 blood samples were taken for C/S from various sections of the Hospital. The antimicrobial sensitivity was done by Kirby-Bauer disc diffusion method as approved by Clinical and Laboratory Standard Institute (CLSI). Results: Out of 1100 Blood samples, 65 samples of blood cultures were positive for Gram –ve Rods. The prevalence of Gram negative Rods in blood specimens was only 6%. Out of 6% gram –ve rods, 12% were E.coli, 9% Klebsiella, 3% Enterobacter cloacae, 45% Salmonella, 2% Proteus, 17% Pseudomonas, 10% Acinetobacter and 2% were serretia. Conclusion: The prevalence of Gram negative rods in blood specimens was only 6%. Keywords: Gram negative rods, blood cultures, Antibiotic sensitivity pattern

Etiological Agent and Their Antibiotic Susceptibility Pattern Causing Adult Septicaemia in a Critically Ill Patients in a Tertiary Care Setting

Objective: To determine bacterial profile in adult sepsis with their antimicrobial susceptibility pattern in our setup.
 Study Design: Cross-sectional study.
 Place and Duration of Study: Microbiology Department, Armed Forces Institute of Pathology, Rawalpindi Pakistan, from Dec 2018 to Dec 2019.
 Methodology: Paired blood culture was collected in automated bottles and was processed as per standard protocol. The isolates were further identified and their susceptibility was performed according to Clinical and Laboratory Standards Institute (CLSI) 2019 guidelines.
 Results: A total of 580 suspected septicaemia cases were taken into consideration. 169 (29.4%) were positive on blood cultures. Among culture-positive samples, Gram-negative bacilli (GNB) accounted for 113 (66.3%) isolates, while the remaining 56 (33.1%) were gram-positive isolates. Within gram-negative isolates, the most common species were 36 (31.8%) Klebsiella pneumonia, followed by 27 (23.8%) Acinetobacter species and 15 (13.2%) Escherichia coli. Multi-drug resistance (MDR) was observed in 98 (86.7%) isolates. Extended-spectrum beta-lactamase production (ESBL) was reported in 73 (64.6%) of enterobacterial. Among 56 Gram-positive bacterial isolates, 25 (44.6%) were Methicillin-resistant Staphylococcus aureus (MRSA), 23 (41%) were Methicillin-resistant coagulase-negative Staphylococcus (MR-CONS). Of the isolates, 8 (14%) were Methicillin sensitive Staphylococcus aureus (MSSA). None of the MR-CoNS and S. aureus strains was resistant to vancomycin.
 Conclusion: Gram-negative bacilli outnumbered Gram-positive organisms in adult septicaemic patients. The majority of these organisms were multidrug-resistant, necessitating the need for timely culture and adjusting antimicrobials according to susceptibility profile.

Diagnostic Accuracy of CHROMagar MRSA for Detection of Methicillin-Resistant Staphylococcus Aureus (MRSA) from Screening Swab Specimens

Objective: To determine the diagnostic accuracy of CHROMagar MRSA for detecting MRSA from screening swab specimens keeping the Cefoxitin disk diffusion test as the reference method.
 Study Design: A cross-sectional validation study.
 Place and duration of study: Department of Microbiology, Armed Forces Institute of Pathology (AFIP), Rawalpindi Pakistan, from Mar to Aug 2019.
 Methodology: A total of 243 screening swab specimens, e.g., axillary, nasal and web swabs, each of hospitalized patients and healthcare workers (HCW) submitted for MRSA screening were included in the study and were processed simultaneously on blood agar, MacConkey agar and CHROMagar MRSA. The agar plates were incubated at 35°C ± 2°C for 18-24 hours in ambient air. The cefoxitin disk diffusion test followed the isolation and identification of MRSA according to the latest Clinical and Laboratory Standards Institute (CLSI) guidelines. In CHROMagar MRSA screening, after incubation, plates were examined for the presence of mauve colonies (MRSA detected), and the results were obtained and validated against the reference method of Cefoxitin disk diffusion.
 Results: Overall, the diagnostic accuracy of CHROMagar MRSA for detecting MRSA was 97.53%. Diagnostic accuracy of CHROMagar MRSA was 95.1%, 97.5% and 100% in axillary, nasal and web specimens, respectively. The rate of MRSA detection was maximum in axillary swabs, i.e., 40.7%, followed by 29.6% and 9.8% in nasal and web swabs, respectively.
 Conclusion: CHROMagar MRSA is found to be accurate for the detection of MRSA. It is reliable, easy to perform, less timeconsuming, and cost-effective. It is an affordable alternative to the conventional..............

Molecular characterization of integrons and Genotyping of Salmonella enterica isolated from diarrheal animals and humans

Resistance to antibacterial drugs is a major health problem because of its impact . It is important to study the prevalence of antibiotic resistance genes in order to understand.Twenty five Salmonella enterica isolated from human and animal diarrhea. Traditional culture methods, biochemical methods, and molecular methods were used to characterize the samples during December to September 2020 to 2021. Disk diffusion method was used to determine antimicrobial susceptibility patterns of isolates identified as MDR by the Clinical and Laboratory Standards Institute (CLSI). The PCR amplification was used to show presence of class 1, 2 and 3 integrons. Class 1 integrons and class3 were detected in 100% of the multidrug-resistant Salmonella isolates,whlie class2 detected among 40%. RAPD-PCR fingerprinting regarded successfully as a reliable, reproducible, accurate and sensitive discriminatory method to Salmonella enterica. The results of RAPD-PCR amplification of Salmonella enterica isolates revealed that 24 isolates (96.%) also showed about one to six amplification bands per isolate, except one isolates were untypeble. The most frequent band was a 1400bp band (72%), while the lowest frequent band was 400bp (8%) among an individual isolates.

Extensively Drug-Resistant Typhoidal Salmonellae: Are These Bugs Swarming Into Suburban and Rural Areas of Pakistan?

BackgroundTyphoid is a serious public health concern with increasing antibiotic resistance. Early suspicion and choice of susceptible antibiotics are key to avoiding the morbidity and mortality associated with this disease. We have carried out this study to assess the antibiotic sensitivity of typhoidal salmonellae in Kharian, Pakistan.Materials and methodsThis cross-sectional study was carried out at Combined Military Hospital, Kharian, Pakistan, from January 2019 to September 2020. Blood culture specimens from patients clinically suspected of enteric fever were tested through the BacT/ALERT 3D automated blood culture system. Positive microbial growth was further identified by colony morphology, appropriate staining, biochemical testing, and Salmonella-specific grouping sera. Salmonella typhi and Salmonella paratyphi A-C were further analyzed for antimicrobial susceptibility using agar disc diffusion testing by the modified Kirby-Bauer technique. The Clinical and Laboratory Standards Institute (CLSI) guidelines (2018-2020) document M-100 was followed for antibiotic selection and assigning the sensitivity status of the isolates. Meropenem and azithromycin were additionally tested keeping in view the possibility of encountering isolates with extensive antimicrobial resistance.ResultsA total of 315 blood culture samples were received during the study period. Of these, 239 (75.9%) reported negative and 76 (24.1%) were positive. The mean age was 22.37 ± 12.39 years. There were 41 (53.9%) males and 35 (46.1%) females. Salmonella enterica (combined Salmonella typhi and Salmonella paratyphi A) was 100% sensitive to azithromycin, meropenem, and imipenem. Ampicillin and chloramphenicol have 28.9% sensitivity each. Ceftriaxone, co-trimoxazole, and ciprofloxacin revealed 64.5%, 23.7%, and 11.8% sensitivity, respectively. Among them, 11.84% of the isolates were pan-sensitive, 35.5% of the cultures were multidrug-resistant (MDR), and 35.5% of the cultures were extensively drug-resistant (XDR).ConclusionThe study demonstrates that polyresistant typhoidal salmonellae are no more confined to a couple of outbreaks in large cities of Pakistan. It is the tip of the iceberg, and the balance has tilted toward difficult-to-treat typhoid and paratyphoid fevers all across the country owing to significant resistance to the commonly used antityphoid antibiotics (cephalosporins and fluoroquinolones). Azithromycin and carbapenems are offering the last line of defense against the rampant Salmonella typhi and Salmonella paratyphi.

Molecular detection of mexXY-oprM, mexPQ-opmE Efflux pumps in multi-drug resistant Pseudomonas aeruginosa isolates in patients referred to teaching hospitals in Babylon province, Iraq

One of the global health issues is antibiotic resistance in Pseudomonas aeruginosa, a causative agent of bacterial infections due to multidrug resistance (MDR), which may be mediated by efflux pumps' overexpression.The present study investigated the prevalence of mexXY-oprM, mexPQ-opmE genes as encoding agents of efflux pumps and the determination of antibiotic resistance rate in clinical isolates of P. aeruginosa.Different clinical specimens of infectious patients, such as wounds, urine, blood, discharge, and abscesses except for stool, were examined. Identification of the isolates was performed using Pseudomonas chromogenic agar. A selective medium for the isolation of P. aeruginosa, used to screen 79 isolates. The results were validated by Polymerase chain reaction (PCR) utilizing particular primer pairs for the 16S rDNA gene of Pseudomonas spp. for identification of the isolates after incubation at 37°C for 24 hours. According to Clinical and Laboratory Standards Institute (CLSI) (2021) recommendations, a microbial susceptibility test was performed using the Kirby–Bauer disk diffusion method. P. aeruginosa was extremely resistant to ceftazidime (93.6%) and cefepime (77.2 %). In contrast, imipenem (77.2%) and meropenem (67%) showed high sensitivity. Finally, mexXY-oprM, mexPQ-opmE genes were investigated by PCR technique. Molecular investigation revealed mexX 43%, mexY 51.89%, oprM 48.1%, mexP 36.70% mexQ 46.83% and opmE 51.89%. The present study concluded that mexXY-oprM and mexPQ-opmE may have a role in P. aeruginosa resistance to various antibiotics. Identifying resistant isolates and antibiotic monitoring programs is essential to prevent the spread of MDR isolates.

Performance evaluation of a laboratory-developed light-initiated chemiluminescence assay for quantification of egg white-specific IgE.

BackgroundSpecific IgE (sIgE) testing has become one of the most important tools for diagnosing IgE‐mediated food allergy. Enzyme‐linked immunosorbent assay (ELISA) and dot‐enzyme‐linked immunosorbent assay (Dot‐ELISA) have been used to measure sIgE in clinical widely. Light‐initiated chemiluminescence assay (LICA) is a new method for measuring allergen‐sIgE. We aimed to establish a LICA method for quantitative detection of egg white‐sIgE and evaluate its performances.MethodsThe best chemibeads coupling method in detecting egg white‐sIgE was selected, and a LICA method for quantitative detection of egg white‐sIgE was established. The precision study was performed according to Clinical and Laboratory Standards Institute (CLSI) EP5‐A2. Detection capability which contains limit of blank (LoB), limit of detection (LoD), and limit of quantitation (LoQ) was evaluated according to National Health Commission of the People's Republic of China (NHC) WS/T 514–2017. Linear range was evaluated according to CLSI EP6‐A. All data were analyzed using SPSS software.ResultsPrecision contains repeatability and intermediate precision. The CV of repeatability ranged from 2.72% to 7.29%, and the CV of intermediate precision ranged from 4.93% to 8.64%. The LoB, LoD, and LoQ of the assay were 0.000 kUA/L, 0.053 kUA/L, and 0.076 kUA/L. The assay linear range was 0.076–34.125 kUA/L (r = 0.9979 ≥ 0.9900).ConclusionThis laboratory‐developed LICA method can detect egg white‐sIgE, and performance meets clinical requirements. This method shows rapid turnaround cycles and high sensitivity. It can be used as an alternative method for clinical detection of egg white‐sIgE.