Multidrug-resistant Isolates Research Articles

The Hidden Threat of Antimicrobial Resistance: A Case Study from A Private Hospital in Jordan

Antibiotic resistance is considered a widespread problem with global health implications, leading to increased patient morbidity and impacting the selection of effective antibiotics, consequently influencing patient recovery. This study aimed to assess antibiogram resistance patterns of bacterial records at the Islamic Hospital in Jordan using a retrospective study during the period 2020-2022. A total of 9369 samples obtained from different patients were cultured. Data were processed and analyzed with SPSS v.23.0. The results showed that 2841 (30.3%) samples were positive for bacterial infections. Microbial profiles of positive samples indicated the highest proportion for Escherichia coli, 39%, followed by Klebsiella pneumoniae 12% were the most frequent Gram-negative bacterial isolates, whereas Staphylococcus aureus 13% and Streptococcus pneumoniae 4% were the most common Gram-positive bacterial isolates. Interestingly, multidrug-resistant bacteria comprised 61.7% of the isolates. The percentage of multi-drug resistance in isolates of Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae was 68.7%, 73.1%, and 72%, respectively. Escherichia coli was most resistant to ampicillin (89%) and most sensitive to imipenem (100%). Klebsiella pneumoniae showed a 100% sensitivity to meropenem but 49% resistance to ceftriaxone. Pseudomonas aeruginosa was the most sensitive to amikacin and colistin (86% and 100%, respectively). Staphylococcus aureus isolates have resistance rates of 78% for ciprofloxacin, 35.6% for clindamycin and an overall resistance rate of 68.7%. These findings indicate multiple resistance for isolated bacteria. Therefore, antimicrobial resistance should be monitored continuously, and patients should be treated based on anti-microbial susceptibility tests.

A multidimensional assessment of in-host fitness costs of drug resistance in the opportunistic fungal pathogen Candida glabrata.

Drug-resistant microbes typically carry mutations in genes involved in critical cellular functions and may therefore be less fit under drug-free conditions than susceptible strains. Candida glabrata is a prevalent opportunistic yeast pathogen with a high rate of fluconazole resistance (FLZR), echinocandin resistance (ECR), and multidrug resistance (MDR) relative to other Candida. However, the fitness of C. glabrata MDR isolates, particularly in the host, is poorly characterized, and studies of FLZR isolate fitness have produced contradictory findings. Two important host niches for C. glabrata are macrophages, in which it survives and proliferates, and the gut. Herein we used a collection of clinical and lab-derived C. glabrata isolates to show that FLZR C. glabrata isolates are less fit inside macrophages than susceptible isolates and that this fitness cost is reversed by acquiring ECR mutations. Interestingly, dual-RNAseq revealed that macrophages infected with drug-resistant isolates mount an inflammatory response whereas intracellular drug-resistant cells downregulate processes required for in-host adaptation. Furthermore, drug-resistant isolates were outcompeted by their susceptible counterparts during gut colonization and in infected kidneys, while showing comparable fitness in the spleen. Collectively, our study shows that macrophage-rich organs, such as the spleen, favor the retention of MDR isolates of C. glabrata.

Genetic Characterization of Multidrug-Resistant Acinetobacter baumannii and Synergy Assessment of Antimicrobial Combinations

Background/Objectives: A. baumannii is a prominent nosocomial pathogen due to its drug-resistant phenotype, representing a public health problem. In this study, the aim was to determine the effect of different antimicrobial combinations against selected multidrug-resistant (MDR) or extensive drug-resistant (XDR) isolates of A. baumannii. Methods: MDR or XDR A. baumannii isolates were characterized by assessing genes associated with drug resistance, efflux pumps, porin expression, and biofilm formation. The activities of antimicrobial combinations including tigecycline, ampicillin/sulbactam, meropenem, levofloxacin, and colistin were evaluated using checkerboard and time-to-kill assays on isolates with different susceptibility profiles and genetic characteristics. Results: Genetic characterization of MDR/XDR strains (n = 100) included analysis of OXA-24/40 gene carbapenemase (98%), genes encoding aminoglycoside-modifying enzymes (44%), and parC gene mutations (10%). AdeIJK, AdeABC, and AdeFGH efflux pumps were overexpressed in 17–34% of isolates. Omp33-36, OmpA, and CarO membrane porins were under-expressed in 50–76% of isolates; CarO was overexpressed in 22% of isolates. Isolates showed low biofilm production (11%). Synergistic activity was observed with levofloxacin-ampicillin/sulbactam and meropenem-colistin, which were able to inhibit bacterial growth. Conclusions: Genetic characteristics of A. baumannii were highly variable among the strains. Synergistic activity was observed with meropenem-colistin and levofloxacin-ampicillin/sulbactam combinations in the checkerboard method, but not in the time-to-kill assays. These discrepancies among both methods indicate that further studies are needed to determine the best therapeutic combination for treating infections by A. baumannii.

Serotypes, Antimicrobial Susceptibility, and Potential Mechanisms of Resistance Gene Transfer in Erysipelothrix rhusiopathiae Strains from Waterfowl in Poland

Erysipelas is a significant problem in the waterfowl farming in Poland, and information on the characteristics of the Erysipelothrix rhusiopathiae strains causing this disease is limited. In this study, we determined the serotypes, antimicrobial susceptibility, and potential mechanisms of resistance gene transfer in E. rhusiopathiae isolates (n = 60) from domestic geese and ducks. We also developed a multiplex PCR for the detection of resistance genes. The antimicrobial susceptibility of the isolates was assessed using the broth microdilution method. Resistance genes, integrative conjugative element (ICE)-specific genes, phage-specific genes, and serotype determinants were detected by PCR. Multilocus sequence typing (MLST) was performed for selected resistant strains. The comparative analyses included 260 E. rhusiopathiae strains whose whole genome sequences (WGSs) are publicly available. E. rhusiopathiae isolates represented 7 serotypes, among which serotypes 5 (38.3%) and 1b (28.3%) were the most common. All strains were susceptible to β-lactams, and the vast majority of them were resistant to tetracycline (85%) and enrofloxacin (80%). The percentages of isolates resistant to other antimicrobials used ranged from 3.3% to 16.7%. Ten isolates (16.7%) were found to be multidrug resistant (MDR). The genotypic resistance profiles of the E. rhusiopathiae strains corresponded to their phenotypic resistance, and the amplification patterns obtained using the 10-plex PCR developed in this study were fully consistent with the results of single PCRs. The most prevalent resistance gene was tetM. In enrofloxacin-resistant strains, nonsynonymous mutations in the gyrA and parC genes were identified. The presence of ICE-specific genes was confirmed in resistant strains, and in MDR isolates of serotype 8 that represented sequence type (ST) 113, prophage DNA (Javan630-like) linked to the lsaE gene was additionally detected. The results indicate that β-lactam antibiotics should be the first choice for the treatment of waterfowl erysipelas in Poland. ICEs, including a transposon from the Tn916/Tn1545 family, and bacteriophages are most likely responsible for the transfer of resistance genes in E. rhusiopathiae.

Extended-spectrum beta-lactamase-producing Enterobacterales in human health: Experience from the tricycle project, Ghana.

Vulnerable groups, such as pregnant women, are at increased risk of potentially life-threatening infections with extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E) for both mother and newborn. However, data regarding ESBL-E carriage and associated risk factors in Ghanaian pregnant women remain scarce. This study aimed to determine the prevalence of ESBL-E carriage and its associated risk factors among pregnant women attending the antenatal clinic at the Korle Bu Teaching Hospital. A systematic sample of 700 pregnant women with gestational age ≥ 34 weeks attending the antenatal clinic at Korle Bu Teaching Hospital was included in the study. After administering a structured questionnaire to assess potential risk factors associated with ESBL-E carriage, patients were given a sterile stool container to submit at least 1 g of stool specimen. Recovered isolates from faecal specimens were identified using MALDI-TOF-MS technology. These isolates were then subjected to susceptibility testing and ESBL identification. A random subset of 24 ESBL-producing Escherichia coli isolates was whole-genome sequenced on the MiSeq Illumina platform. Risk factors associated with ESBL-E carriage were determined using multivariable logistic regression analysis. Among the 700 pregnant women, 42% (294) carried ESBL-E. The predominant ESBL-producing Enterobacterales were Escherichia coli (95%). Fifty percent (50%) of ESBL-E were multidrug resistant isolates (MDRs). Whole-genome sequencing of 24 ESBL-producing E. coli isolates revealed that blaCTX-M-15 (96%) was the most prevalent ESBL gene type. Notably, most isolates belonged to commensal phylogenetic groups (A, B1, and C; 88%). Having a primary level of education (aOR 1.45, 95% CI 1.05-1.96) and consuming legumes as the main source of protein (aOR 0.17, 0.40-0.83) were significantly associated with intestinal carriage of ESBL-E. This study identified a high prevalence of ESBL-E and MDR-ESBL-E carriage among pregnant women. Our findings underscore the urgent need for public health interventions to control the spread of AMR.

Coexistence of the blaZ gene and selected virulence determinants in multidrug-resistant Staphylococcus aureus: insights from three Nigerian tertiary hospitals.

Infections caused by β-lactamase-producing strains of Staphylococcus aureus have become increasingly difficult to treat due to the expression of multiple virulence factors. This has heightened concerns about managing S. aureus-related infections. This study was conducted to characterize the blaZ gene and selected virulence determinants in β-lactam resistant S. aureus from human sources in three Nigerian tertiary hospitals. Three hundred and sixty samples were collected for the study. S. aureus was isolated and characterized following standard microbiological protocols and nuc gene amplification. Antibiotic susceptibility and minimum inhibitory concentration tests were performed using the disk diffusion method and E-tests, respectively. Biofilm formation and β-lactamase production were assessed using Congo red agar and nitrocefin kits, while the blaZ gene was examined using conventional PCR. Capsular polysaccharide genotyping, accessory gene regulator (agr) detection, Panton-valentine leucocidin (PVL), and PVL proteins were performed using PCR and Western blotting. S. aureus was recovered from 145 samples, 50 (34.5%) of these isolates exhibited multidrug resistance, with MICs ranging from 0.125 to 1.00µg/mL, and showed significant resistance to aminoglycosides, fluoroquinolones, and β-lactams. Of these, 31 strains produced β-lactamases, 30 of which carried the blaZ gene in combination with cap8 (80%) or cap5 (20%). Biofilm formation and PVL gene were observed in 85% of the 20 randomly selected blaZ-positive multidrug-resistant (MDR) strains. The agr2 allele was predominant, found in 70% of the selected MDR strains. No significant difference in the occurrence of the blaZ gene was found among the three clinical sources (p ≤ α0.05). The co-occurrence of the blaZ gene with PVL, capsular polysaccharide genes, and agr alleles is associated with biofilm formation, indicating a high risk of β-lactam-resistant S. aureus infections. Our findings highlight the need for continuous molecular surveillance to enhance infection management, treatment options, and patient outcomes in the study locality. A limitation of this study is the random selection of MDR isolates, which may affect the comprehensiveness of the analyses.

FOSFOMYCIN SUSCEPTIBILITY IN MULTIDRUG-RESISTANT UROPATHOGENS: A RETROSPECTIVE STUDY IN THE ERA OF ANTIMICROBIAL RESISTANCE

Objective: Urinary tract infection (UTI) is one of the most prevalent clinical entities affecting people worldwide. The accelerating rate of Antimicrobial resistance due to the unimpeded and rampant use of antimicrobials with over-the-counter availability of drugs has limited the therapeutic options for the treatment of UTIs. Fosfomycin, an old broad-spectrum antimicrobial with good pharmacokinetics has regained importance for the treatment of multidrug-resistant (MDR) isolates. The purpose of this study was to determine the in vitro Fosfomycin susceptibility of common uropathogens and to study the resistance pattern of these organisms against commonly prescribed antimicrobial agents. Methods: A retrospective cross-sectional study was conducted in the Bacteriology section of the Microbiology laboratory at Adesh Institute of Medical Sciences and Research, Bathinda, Punjab for duration of 6 months from December 2022 to May 2023 from urine samples received from all clinically suspected cases of UTI. Samples were processed immediately as per standard microbiological techniques, followed by culture by a semi-quantitative method. Kass criteria was followed for interpretation of significant bacteriuria according to which significant growth was considered if the colony count was more than 105 colony forming units (CFU)/mL. Culture positives were analyzed by Gram staining and on the basis of colony characteristics, Gram staining, final identification, and Antimicrobial Susceptibility were done through Vitek 2 compact system. Results: A total of 2292 urine samples received in the Microbiology laboratory were processed and cultured during the study period, which yielded 509 significant bacterial isolates i.e.509/2292 (22.2%) culture positivity. Among 509 culture-positive samples, Escherichia coli 235/509 (46.1%) was the most common uropathogens isolated followed by Klebsiella pneumoniae 107/509 (21.1%), Enterococcus species 40/509 (7.8%). Fosfomycin depicted good in vitro susceptibility of a minimum of 94% in both Gram-negative and Gram-positive uropathogens as compared to Nitrofurantoin, which showed sensitivity of 74% and 85%, respectively. Maximum resistance was observed toward Cephalosporins i.e., Ceftriaxone in E. coli (60%) and K. pneumoniae (64%), respectively, followed by 50% in Acinetobacter baumannii. Maximum resistance to Ciprofloxacin (62%) was seen in case of A. baumannii. 172/405(42.4%) isolates of Enterobacteriaceae family were extended-spectrum β-lactamase (ESBL) producers with an average Fosfomycin susceptibility of 95.9%. Among the total isolated uropathogens, 135/509 (26.5%) were MDR, out of which 116/135 (85.9%) depicted Fosfomycin susceptibility. Metallo-beta-lactamase (MBL) production was seen in 14.3% of the isolated Gram-negative uropathogens. 63/73(86.3%) of the MBL producers were found susceptible to Fosfomycin. Conclusion: Fosfomycin has emerged as an effective alternative for the treatment of common uropathogens including the MDRs, ESBL producers, and the MBLs in the era of increasing antimicrobial resistance. It has the potential to act as a promising oral agent for the treatment of UTI in both community and healthcare setups.

A peptide targeting outer membrane protein A of Acinetobacter baumannii exhibits antibacterial activity by reducing bacterial pathogenicity.

The World Health Organization has classified multidrug-resistant (MDR) Acinetobacter baumannii as a significant threat to human health, necessitating the urgent discovery of new antibacterial drugs to combat bacterial resistance. Outer membrane protein A of A. baumannii (AbOmpA) is an outer membrane-anchored β-barrel-shaped pore protein that plays a critical role in bacterial adhesion, invasion, and biofilm formation. Therefore, AbOmpA is considered a key virulence factor of A. baumannii. Herein, we screened three phage display peptide libraries targeting AbOmpA and identified several peptides. Among them, P92 (amino acid sequence: QMGFMTSPKHSV) exhibited the highest binding affinity with AbOmpA, with a KD value of 7.84 nM. In vitro studies demonstrated that although P92 did not directly inhibit bacterial growth, it significantly reduced the invasion and adhesion capabilities of multiple clinical isolates of MDR A. baumannii and concentration-dependently inhibited biofilm formation by acting on OmpA. Furthermore, the polymerase chain reaction results confirmed a significant positive correlation between the antibacterial effect of P92 and OmpA expression levels. Encouragingly, P92 also displayed remarkable therapeutic efficacy against A. baumannii infection in various models, including an in vitro cell infection model, a mouse skin infection model, and a mouse sepsis model. These results highlight P92 as a novel and highly effective antimicrobial molecule specifically targeting the virulence factor AbOmpA.

Characterization of Extended Spectrum Beta-lactamase Uropathogens Isolated from Refugees with Urinary Tract Infections in Nakivale Refugee Settlement Camp, Southwestern Uganda

The World Health Organization estimates one in four individuals has had at least one urinary tract infection (UTI) episode requiring treatment with an antimicrobial agent. At Nakivale refugee camp, the overwhelming number of refugees often associated with poor living conditions predispose the refugees to urinary tract infections. This study determined the prevalence of UTIs, the antimicrobial susceptibility pattern of the isolated bacterial pathogens, the prevalence of Extended-Spectrum Beta-Lactamase (ESBL) bacteria, and the molecular characterization of genes encoding ESBLs among refugees in the Nakivale refugee settlement. This was a cross-sectional study that involved 216 outpatients who visited Nakivale Health Centre III between July and September 2020. The urine samples were received and examined at the microbiology laboratory of Mbarara University of Science and Technology. The urine samples were cultured and identified. Antibiotic susceptibility was carried out following CLSI recommended guidelines while the presence of genes encoding ESBL was detected using conventional PCR amplification. The prevalence of UTI was 24.1% (52/216). Staphylococcus aureus was the most prevalent causative agent, accounting for 22/52 (42.31%) of total isolates, followed by Escherichia coli 21/52(40.38%). Multidrug-resistant isolates accounted for 71.15% (37/52). A total of twenty-one isolates (70.0%) were extended spectrum beta-lactamase producing bacteria. The most prevalent genes were TEM beta-lactamase (blaTEM) and CTX-M beta-lactamase (blaCTX-M). The prevalence of UTI among refugees in the Nakivale settlement was high which calls for continuous epidemiological surveys to determine the prevalence of multi-drug resistance uropathogens including ESBL-producing organisms across refugee camps in Uganda.

Genomic diversity of Campylobacter jejuni and Campylobacter coli isolates recovered from human and poultry in Australia and New Zealand, 2017 to 2019.

We used genomic and epidemiological data to assess and compare the population structure and origins of Campylobacter, a major foodborne pathogen, in two neighbouring countries with strong trade and cultural links, similar poultry production systems and frequent movement of people and food products. The most common sequence types (STs) differed between Australia and New Zealand, with many unique to each country. Over half of all STs were represented by a single isolate. Multidrug-resistant (MDR) genotypes were detected in 0.8% of all samples, with no MDR isolates detected in poultry. Quinolone and tetracycline resistant ST6964 was prevalent in New Zealand (10.6% of C. jejuni). Closely related isolates suggested some similar food sources or contacts. We have shown that there is little genetic overlap in human and poultry STs of Campylobacter between the countries, which highlights that this common foodborne pathogen has domestic origins in Australia and New Zealand.

Bacterial isolates and antibiotic sensitivity in canine bacterial keratitis in Korea.

To analyze bacterial isolates associated with canine bacterial keratitis and their antibiotic susceptibility patterns in Korea, focusing on multidrug resistance (MDR) and identifying effective antibiotic combinations for clinical treatment. A total of 146 dogs diagnosed with suspected bacterial keratitis between October 2022 and October 2023 in Korea, with 157 eye samples collected for analysis. Eye samples were cultured to isolate bacteria, and antibiotic susceptibility testing was performed using the minimum inhibitory concentration (MIC) method. Bacterial identification was conducted using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF). The study assessed the efficacy of individual antibiotics and combination therapies. Bacteria were isolated in 55.4% of the samples. The most common genera were Staphylococcus species (48.5%, 48/99), Streptococcus species (13.1%, 13/99), Pseudomonas species (9.1%, 9/99), and Escherichia coli (9.1%, 9/99). Amikacin (84.8%) showed the highest antibiotic susceptibility, while doxycycline exhibited the lowest (17.2%). The most effective antibiotic combinations were amikacin-moxifloxacin (93%). MDR isolates accounted for 52.5% (52/99) of the total bacterial samples. Staphylococcus species were the most common isolates, with 52.5% showing MDR, underscoring the need to curb antibiotic misuse. While antibiotics like amikacin demonstrated high susceptibility rates, their use should be reserved for resistant infections to prevent further resistance development. Rather than focusing solely on finding effective combinations of antibiotics, it is crucial to consider alternative treatment strategies that offer more sustainable solutions. Rather than relying on antibiotic combinations, attention should shift to sustainable alternatives to treat bacterial keratitis and reduce antibiotic dependence in clinical practice.

Linear and Polyvalent Peptides with Potent Antimicrobial Activity Against Sensitive and Multidrug-Resistant E. coli Clinical Isolates.

Peptides containing the sequences 20RRWQWR25 and 20RRWQWRMKKLG30 derived from Bovine lactoferricin (LfcinB) were synthesized and their antibacterial effect against reference strains and sensitive and resistant clinical isolates of E. coli was evaluated. Tetra-branched multiple antigen peptide (MAP) ((RRWQWR)2-K-Ahx-C)2 exhibited significant antibacterial activity against sensitive, resistant, and multidrug-resistant clinical isolates of E. coli. Peptide 3: RRWQWR-Nal-KKLG; MIC=16 µM, 26[F]: (RRWQWRFKKLG)2-K-Ahx; MIC=15 µM, 17: (RRWQWRFK)2-K-Ahx; MIC=9 µM, and LfcinB (20-25)2: (RRWQWR)2-K-Ahx; MIC=11 µM exhibited the highest antibacterial activity against E. coli strains, with bactericidal effect and haemolytic effect at MIC less than 5% and a therapeutic index >1. A synergistic effect of peptides 26[F] and 17 with ciprofloxacin (CIP) or ceftriaxone (CEF) was observed. Prolonged treatment of E. coli ATCC 25922 with sublethal concentrations of CIP induced resistance in this strain, whereas some peptides did not induce resistance. These peptides can be considered to be promising candidates for treating infections caused by resistant strains of E. coli.

Multicentre Study of Candida parapsilosis Blood Isolates in Türkiye Highlights an Increasing Rate of Fluconazole Resistance and Emergence of Echinocandin and Multidrug Resistance.

Worldwide emergence of clonal outbreaks caused by fluconazole-resistant (FLCR) and the recent emergence of echinocandin- and multidrug-resistant (ECR and MDR) Candida parapsilosis isolates pose serious threats to modern clinics. Conducting large-scale epidemiological studies aimed at determining the genetic composition and antifungal resistance rates is necessary to devise antifungal stewardship and infection control strategies at international, national and local levels. Despite being severely hit by outbreaks due to FLCR C. parapsilosis isolates, such knowledge at the national level is lacking in Türkiye. Herein, we conducted a prospective multicentre study involving five major clinical centres in Türkiye to determine antifungal resistance rates, underlying mechanisms and genetic composition of all isolates. In total, 341 isolates were collected from 265 patients including clinical information. Antifungal susceptibility testing against common antifungals was performed in addition to sequencing of ERG11 and FKS1. Last, isolates were genotyped with short tandem repeat (STR) genotyping to investigate potential nosocomial transmission. The FLCR rate was 26.7% (91/341), out of which 75.8% (69/91) harboured the ERG11Y132F mutation. Patients infected with FLCR isolates had a higher mortality rate compared to their susceptible counterparts (49% for FLCR vs. 42% for susceptible). ECR rate was 2.1% (7/341) and isolates carried FKS1F652L/R658G/W1370R mutations. Concerningly, four ECR isolates were MDR. FLCR isolates grouped in distinct clusters without evidence of inter-hospital transmission, whereas large clusters containing susceptible isolates from all centres were noted. Overall, the increasing prevalence of FLCR C. parapsilosis at national level and the emergence of ECR and MDR isolates pose serious clinical challenges in Türkiye. Therefore, conducting large-scale epidemiological studies are critical to determine the trend of antifungal resistance and to tailor pertinent antifungal stewardship and infection control strategies to effectively curb the spread of drug-resistant C. parapsilosis.

Identification and antimicrobial susceptibility profiles of Campylobacter isolated from camel at municipal abattoirs in eastern Ethiopia

Campylobacteriosis is an infectious zoonotic disease caused by the genus Campylobacter. The disease is transmitted from animals to humans predominantly through the consumption of contaminated food and water. However, the lack of information on the status of Campylobacter makes it difficult to quantify the role of camel meat in the dissemination of the pathogen. A cross-sectional study was conducted from June 2022 to August 2023 to investigate the occurrence of Campylobacter and associated risk factors and to determine the antimicrobial susceptibility profiles of Campylobacter species from camels slaughtered at municipal abattoirs in the towns of Harar, Babile, Jigjiga and Dire Dawa in eastern Ethiopia. A total of 324 (146 carcass swabs, 146 camel feces and 32 abattoir environmental swab samples) were collected and analyzed using TaqMan real-time PCR and culture techniques following standard procedures. In addition, antimicrobial susceptibility tests were performed using the disk diffusion method for eight antimicrobial agents according to the Clinical Laboratory Standards Institute. The overall prevalence of Campylobacter was 7.7%. Campylobacter was more frequently detected from carcasses and surface contact environmental swabs. We isolated Campylobacter at the genus level from approximately half of the PCR-positive samples, representing 54.2% (13 out of 24) of the total. The isolation levels of C. jejuni and C. coli were also 5.56% and 2.2%, respectively, which varied significantly (p = 0.037) based on sample type and site. The odds of occurrence of C. jejuni in samples collected from abattoir environments was 7.52 times greater than those in carcass and fecal samples. We detected resistance to chloramphenicol (78.6%), followed by amoxicillin (71.4%). However, 93%, 78.6%, and 71.4% of the isolates were susceptible to ceftriaxone, ciprofloxacin, and nalidixic acid, respectively. Multidrug resistance (MDR) was detected in 60% of the isolates. Of these MDR isolates, 9 (75%) were C. jejuni and 3 (25%) were C. coli. This study revealed that a considerable proportion of multidrug-resistant Campylobacter species circulate in both camel meat and abattoir environments. This indicates possible carcass cross-contamination by Campylobacter during slaughtering that can pose a threat to humans and limit therapeutic options, which could be prevented by applying good hygienic practices at abattoirs. Therefore, abattoir workers need to be aware of abattoir hygienic standard operating procedures. Regular coordinated actions should be implemented for the rational use of veterinary and medical drugs at the national level, together with training and awareness of hygienic practices.

Antifungal resistance, clinical outcome and clinico-microbiological correlation in ocular infections due to common melanized fungi Curvularia lunata and Lasiodiplodia theobromae in South India.

Aim. Melanized fungi were rarely studied for their antifungal resistance (AFR) or clinical outcome, despite rising incidence of melanized fungal ocular infections and AFR in general. We report the antifungal resistance patterns, clinical outcome and clinico-microbiological correlation in two commonly isolated melanized fungi from ocular infections, Curvularia lunata and Lasiodiplodia theobromae, at a tertiary eyecare centre in South India.Gap statement. Despite melanized fungi accounting for a significant proportion of ocular fungal infections in the Indian subcontinent, and despite there being a limited selection of effective antifungal agents available for these infections, the existing data and studies on these issues remain sparse. Therefore, this study aimed to investigate the prevalence of antifungal resistance in two of the most common melanized fungal pathogens in ocular infections, Curvularia lunata and Lasiodiplodia theobromae and correlate it with the treatment given and the clinical outcome in patients.Methodology. Electronic medical records provided the clinical data. Standard broth microdilution was performed for antifungal susceptibility testing (AFST) in 30 isolates (17 C. lunata and 13 L. theobromae) for amphotericin B and natamycin (polyenes): voriconazole, ketoconazole, posaconazole, itraconazole and fluconazole (azoles) and caspofungin (echinocandin). Multidrug resistance (MDR) was defined as resistance to more than or equal to two classes of antifungals. DNA sequencing was performed for the isolates for species confirmation. The multivariate analysis was done for determining poor prognostic factors.Results. AFST showed highest susceptibility of study isolates for voriconazole (83.3% isolates), followed by natamycin (80%), fluconazole (80%), itraconazole (76.7%), ketoconazole (70%), posaconazole (66.7%), caspofungin (66.7%) and lastly amphotericin B (63.3%). All patients empirically received topical natamycin; additional oral ketoconazole/intraocular voriconazole was administered in select few. MDR was strongly associated with poor clinical outcome (multivariate analysis: P = 0.03, odds ratio = 7.8). All patients had microbial keratitis, one progressed to endophthalmitis. Additionally, therapeutic penetrating keratoplasty was required in 40% of cases. Globe salvage was possible in 80% patients, though good visual outcome was seen in only half of them. Both, anatomical and visual outcomes, were poor in 20% of patients. DNA sequencing showed C. lunata as the highest study species.Conclusion. C. lunata and L. theobromae showed varying in vitro antifungal susceptibility and clinical outcome in ocular infections. Voriconazole had significantly higher activity, while amphotericin B had lower activity in vitro for these melanized fungi. MDR isolates showed poorer clinical outcome.

Genetic Insights on Meropenem Resistance Concerning Klebsiella pneumoniae Clinical Isolates

The transferable genetic elements are associated with the dissemination of virulence determinants amongst Klebsiella pneumoniae. Thus, we assessed the correlated antimicrobial resistance in carbapenem-resistant Klebsiella pneumoniae clinical isolates. Each isolate’s ability to biosynthesize biofilm, carbapenemase, and extended-spectrum β-lactamase were examined. Genotypically, the biofilm-, outer membrane porin-, and some plasmid-correlated antimicrobial resistance genes were screened. About 50% of the isolates were multidrug-resistant while 98.4% were extended-spectrum β-lactamase producers and 89.3% were carbapenem-resistant. Unfortunately, 93.1% of the multidrug-resistant isolates produced different biofilm levels. Additionally, fimD and mrkD genes encoding adhesins were detected in 100% and 55.2% of the tested isolates, respectively. Also, the blaKPC, blaOXA-48-like, and blaNDM-encoding carbapenemases were observed in 16.1%, 53.6%, and 55.4% of the tested isolates, respectively. Moreover, the blaSHV and blaCTX-M extended-spectrum β-lactamase-associated genes were detected at 95.2% and 61.3%, respectively. Furthermore, aac(3)IIa, qnrB, and tetB resistance-correlated genes were observed in 38.1%, 46%, and 7.9% of the tested isolates, respectively. Certainly, the tested antimicrobial resistance-encoding genes were concurrently observed in 3.2% of the tested isolates. These findings confirmed the elevated prevalence of various antimicrobial resistance-associated genes in Klebsiella pneumoniae. The concurrent transferring of plasmid-encoding antimicrobial resistance-related genes could be associated with the possible acquisition of multidrug-resistant Klebsiella pneumoniae phenotypes.

Prevalence, Risk Factors, and Antimicrobial Resistance of Staphylococcus and Streptococcus Species Isolated from Subclinical Bovine Mastitis.

Subclinical mastitis (SCM) is a prevalent serious disease among dairy cows worldwide. It poses a significant challenge to the dairy industry, animal welfare, and a threat to public health. The present study aimed to investigate the molecular detection, prevalence, and antimicrobial resistance of Staphylococcus spp. and Streptococcus spp. isolated from raw composite milk samples obtained from SCM dairy cattle in Bangladesh. A total of 612 quarters milk samples obtained from 153 cows were analyzed for SCM using the California Mastitis Test. Bacterial isolation and identification were carried out and bacterial species were confirmed using molecular polymerase chain reaction methods. Antimicrobial susceptibility testing was performed using disc diffusion method. The findings revealed that the prevalence of SCM was 70.3% (26/37), 35.95% (55/153), and 23.04% (141/612) in the herd, cow, and quarter levels, respectively. Among the positive samples, 92.7% (51/55) were Staphylococcus spp. (S. aureus, S. chromogenes, and S. simulans) and the remaining isolates were 7.3% (4/55) Streptococcus spp. (Streptococcus agalactiae and Streptococcus dysgalactiae). The most prevalent species was S. chromogenes, accounting for 67.3% (37/55). Antimicrobial susceptibility testing showed that 65.5% of isolates were susceptible to cefoxitin, whereas, 89.1% were resistant to penicillin. Overall, 12 isolates (21.8%) out of 55 were resistant to more than three classes of antimicrobials and were defined as multidrug-resistant isolates. Methicillin-resistance gene was detected in 61.1% of the cefoxitin-resistant isolates. A multivariate logistic regression analysis identified five potential risk factors including the lack of post-milking teat disinfection (OR: 3.06), absence of immediate feeding after milking (OR: 9.81), poor udder hygiene (OR: 7.83), tick infestation (OR: 13.76), and absence of dry cow therapy (OR: 3.31). The findings of the current study underscore the urgent requirement for targeted interventions, considering the identified factors to effectively manage and control SCM in dairy cows.

Detection of Efflux pump MexX and MexY genes in Multidrug Resistant Pseudomonas aeruginosa

High antibiotic resistance among Pseudomonas aeruginosa could be viewed as the primary cause of nosocomial infections. In this study, 60 isolates of Pseudomonas aeruginosa were isolated from urine, sputum, burn, ear and wounds swab. The major goal was to determine the relationship between MexX and MexY and the resistance of MDR P. aeruginosa to many drugs. Prevalence of multidrug resistant (MDR) Pseudomonas aeruginosa was 22 isolates (36.66%) and 38 isolates (63.34%) were found to be non-MDR isolates. Moreover, molecular detection of MexX and MexY genes was done for MDR isolates.MexY gene was found in all MDR isolates and MexX gene was detected in 20 (90.9%) MDR isolates. Susceptibility test showed highly significant differences p≤0.01. Highest resistance was found against piperacillin/sulbactam (45%), followed by ceftazidime/avibactam with 33.33%, and by ceftolozane/tazobactam and levofloxacin which shared same percentage at 31.67%. Almost 23.33% were less resistant to both doripenem and colistin, and 25% to tobramycin. All these findings confirmed a positive correlation between the presence of MexX and MexY genes and an increase in the resistance for all antibiotics used in this study the results of which were highly significant at p≤0.01 for all antibiotics. The study found that some antibiotics that had not been studied previously, also had a relationship with the presence of these genes and the resistance of bacteria to antibiotics such as penicillin, unlike it was previously believed that they do not have relation with the efflux pump mechanism in P. aeruginosa and that this bacterium use other mechanisms to resist them.

Characterization of bla NDM in two Escherichia coli ST1193 clinical isolates in the Gulf region.

Escherichia coli ST1193 is an emerging high-risk clone associated with the production of plasmid-mediated CTX-type extended-spectrum β-lactamases. However, this clone has seldom been found to contain plasmids carrying carbapenemase genes. We report two epidemiologically unlinked multidrug-resistant (MDR) clinical isolates of E. coli ST1193 with plasmids harbouring NDM-type carbapenemase genes from the Gulf region. The isolates were identified by MALDI-TOF MS and antibiotic susceptibility testing was performed using the VITEK 2/Phoenix system. A conjugation experiment was performed to assess the transferability of the resistance plasmids. Genomic DNA of both isolates was subject to Illumina sequencing; one isolate was also sequenced using Oxford Nanopore technology. Bioinformatics analyses were performed to detect antimicrobial resistance genes, and to annotate the genetic context of the NDM genes. Both isolates were resistant to carbapenems using phenotypic tests. Conjugation experiment confirmed that NDM-5-encoding plasmids of both strains could be transferred to the recipient cells. The completed NDM-5-encoding plasmid of E. coli isolate FQ71 was highly similar to several plasmids from ST410 isolates in the NCBI database. Genomic analysis revealed the presence of transposase genes and transposons in the flanking regions of the NDM genes in the plasmids. Since carbapenems constitute first-line agents for the treatment of serious infections caused by ESBL producers, E. coli ST1193 isolates co-producing ESBL and NDM-type carbapenemases represent a serious challenge for antimicrobial stewardship and infection control programmes.

Bacterial etiology, antibiotic susceptibility pattern, and treatment modality of surgical site infections among post-caesarean delivery women: A 2019 cross-sectional study conducted in Iringa, Tanzania

Background: Surgical site infection (SSI) is a common complication after cesarean section in Tanzania, with high rates of infection and multidrug-resistant isolates reported. Understanding bacterial etiology and antibiotic susceptibility patterns is crucial for effective treatment and prevention. Therefore, this study aimed to determine the bacterial etiology, antibiotic susceptibility patterns, and treatment modalities of SSI among post-cesarean delivery women in the Iringa region. Methods: A cross-sectional study involving 162 women with SSI was conducted across five hospitals in Iringa. Data on demographics were collected using a structured questionnaire, and wound discharge samples were taken for culture and sensitivity testing. Definitive treatment modalities were identified from patients’ files. Data analysis was performed using SPSS version 20, with chi-square tests used to identify associations, and a p-value < 0.05 considered significant. Results: Among 162 participants, 59.7% had superficial SSIs and 35.2% had deep SSIs. Culture positivity was 96.3%, with 53.2% being gram-positive and 37.2% gram-negative. Staphylococcus aureus was the most commonly isolated pathogen (40.1%), with 64.6% of cases being methicillin-resistant (MRSA). Resistance to vancomycin and chloramphenicol among gram-positive isolates was 3.1% and 13.8%, respectively. Non-surgical management was provided to 58% of the participants, while Staphylococcus aureus infections were significantly associated with surgical intervention (OR = 1.38, p = 0.001). Conclusion: Staphylococcus aureus, particularly MRSA, was the most prevalent pathogen in post-cesarean SSIs. Antibiotic resistance was common, and surgical intervention was significantly associated with Staphylococcus aureus infections.