Association Of Antibiotic Resistance Research Articles

Association of Blaoxa-1 Gene with Multidrug Resistance in K. pneumoniae Clinical Isolates

OBJECTIVES This study aimed to isolate K. pneumoniae from patients samples and find an association of the plasmid-mediated bla-OXA-1 gene with multidrug-resistant K. pneumoniae. METHODOLOGY This cross-sectional study was conducted at Mardan Medical Complex and Khyber Medical University Peshawar. K. pneumoniae was isolated from pus, urine and blood samples by culture and confirmed by biochemical techniques. Antibiotic susceptibility was done by disc diffusion according to the CLSI 2022 guidelines. A polymerase chain reaction was done for the gene after extraction and amplification of plasmid DNA. Furthermore, an association of antibiotic resistance was confirmed with blaOXA-1. RESULTSA total of 160 K. pneumoniae isolates were cultured from the patient’s samples, including pus (135, 84.37%), urine (15, 9.37%) and blood (10, 6.26%). There were 154 (96.3%) isolates resistant to Penicillin-G, followed by Ceftriaxone 151 (94.4%), Cefepime 143 (89.4%), Amoxicillin 125 (78.1%), Tigecycline 110 (68.8%), Imipenem 92 (57.6%) and Ertapenem 75(49.9%). However, Tetracycline had 1.9% resistance. The blaOXA-1 gene was positive in 41(25.62%) isolates with a different pattern of antibiotics resistance to Penicillin-G, Ceftriaxone, Cefepime, Amoxicillin, Tigecycline, Imipenem and Ertapenem as compared to the negative isolates. Among the blaOXA-1 gene-positive K. pneumoniae isolates, resistance to Penicillin-G was 100%, followed by Ceftriaxone (92.7%), Cefepime and Amoxicillin (80.5%), respectively. However, resistance to Imipenem and Ertapenem was 46.3% and 41.5%, respectively, and Tetracycline was not resistant. CONCLUSION Our data suggest that the presence of plasmid associated blaOXA-1 gene in K. pneumoniae isolates may contribute to multidrug resistance in beta lactamase-containing antibiotics along with other internal mechanisms of resistance present in these bacteria.

SCREENING OF ANTIBIOTIC RESISTANCE BETWEEN BIOFILM PRODUCER AND NON-BIOFILM PRODUCER OF KLEBSIELLA PNEUMONIAE ISOLATES

Background: Klebsiella pneumoniae is a common cause of nosocomial infections. Antibiotic resistance and the ability to form biofilm, as two key virulence factors of K. pneumoniae, are involved in the persistence of infections. Aim: determine the rate of (10) antibiotics activity against isolated K. pneumoniae then evaluate the ability of isolated bacteria to produce biofilm by using Congo red agar method and studying the antibiotic resistance pattern between biofilm producer and non-biofilm producer of K. pneumoniae isolates. Material and methods: over a period of 4 months a total of 37 k. pneumoniae isolates were collected. Antibiotic susceptibility was determined by the disc diffusion method according to CLSI. Biofilm production was assessed by Congo red agar method. Results: Antibiotic susceptibility profile showed a variable level of resistance. The highest resistance was reported with tetracycline (56.8%). And the highest susceptibility was reported with imipenem (85.6%) and meropenem (85.6%). Biofilm by Congo red agar method was detected in 19 isolates with a percentage of (51.35%) however, 18 (48.65%) of isolates were non biofilm producer. The association of antibiotic resistance between biofilm-producing and non-biofilm-producing K. pneumoniae isolates was evaluated by the Chi-square test and the p-value was found to be 0.97 (statistically non-significant). Conclusion: our study revealed that the K. pneumoniae isolates differed in their responses against used antibiotics, moreover they are varied in their ability to produce biofilm and the resistance pattern between biofilm producer and non-producer was no significant. More studies are needed to characterize the pattern of antibiotic resistance between biofilm producer and non-biofilm producer of K. pneumoniae isolates and universal efforts should be increased to prevent the prevalence of multi- antibiotic resistant bacteria and eliminate the hospital born bacteria that are causing a great rise in mortality. Keywords: Klebsiella Pneumoniae, Antibiotic Resistance, Biofilm

Enterobacter Cloacae: The association of antibiotic resistance, integron class I and carbapenemase genes

The opportunistic pathogen, E. Cloacae has been reported to carry carbapenemas genes worldwide. Our objective was assessing the association of antibiotic resistance, integron class I and carbapenemase genes among E. Cloacae. Herein, 200 E. Cloacae were collected and identified. The antibiotic resistance of them was evaluated using Kirby Bauer method. The existence of class I integron, carbapenemase genes was investigated using polymerase chain reaction (PCR). Of the 200 E. Cloacae isolates collected, 120 isolates (60%) were from male and 80 isolates (40%) were from females. Of them, 110 isolates (55%) showed a pattern of MDR phenotype. Of these, 18 isolates (9%) showed resistance to imipenem. Based on PCR test, 134 isolates (67%) had class I integrons. Also, out of 110 MDR isolates, 52 isolates (72%) were positive in terms of the presence of class I integrons. Isolates with integrons were mostly from urinary (61%) and blood (44%) and from ICU settings (46%) and inpatients (38%). A significant relationship was observed between the presence of integron and resistance to ciprofloxacin, imipenem, meropenem, and norfloxacin antibiotics. The prevalence of blaIMP, blaOXA-48 were 18% and 4%, respectively, but none of other carbapenemase genes were detected. The existence of class I integron was high among E. Cloacae from Baghdad city. The carriage of genes resistance to carbapenems were significantly associated to the class I integrin.

Association of Antibiotic Resistance, Cell Adherence, and Biofilm Production with the Endemicity of Nosocomial Klebsiella pneumoniae.

Klebsiella pneumoniae is a leading cause of multiple nosocomial infections, some of which are associated with high mortality. The increasing prevalence of antibiotic-resistant strains highlights their clinical importance and how complicated managing treatment can be. In this study, we investigated antimicrobial resistance, cell adherence, and biofilm production of nosocomial K. pneumoniae strains isolated from surveillance studies in a Mexican tertiary hospital and evaluated the potential association of these phenotypes with endemicity. The great majority of the clones exhibited adhesion to cultured epithelial cells and were strong biofilm producers. A direct relationship between adhesion phenotypes, biofilm production, and endemicity was not always apparent. Biofilm formation and production of ESBL did not appear to be directly associated. Notably, all the endemic strains were multidrug-resistant. This study emphasizes that while endemic strains possess various virulence-associated properties, antimicrobial resistance appears to be a determining factor of their endemicity.

Characteristics of Dogs with Biofilm-Forming Escherichia Coli Urinary Tract Infections.

BackgroundBacterial urinary tract infections (UTIs) are common in companion animals. Increasing awareness of biofilm‐forming bacteria raises concern regarding the appropriate diagnosis, treatment, and prognosis of UTIs associated with these organisms.Hypothesis/ObjectivesTo (1) describe the population of dogs with UTIs associated with biofilm‐forming Escherichia coli and (2) determine whether or not clinical differences exist between dogs with biofilm‐forming E. coli UTIs and dogs with nonbiofilm‐forming E. coli UTIs. We hypothesized that there would be no difference in the population characteristics, but that biofilm‐formation would be more prevalent in dogs with chronic, complicated, and asymptomatic UTIs.AnimalsSeventy‐six client‐owned dogs with E. coli UTIs, divided into 2 groups based on the biofilm‐forming capability of stored bacterial isolates as assessed by the crystal violet assay.MethodsRetrospective cross‐sectional study. Medical records of the affected dogs were reviewed and their population and infection characteristics were compared.ResultsMost (52.6%) E. coli isolates were capable of forming biofilms. Biofilm‐forming E. coli had a lower likelihood (P < .001) of multidrug resistance than did nonbiofilm‐forming E. coli. No statistically significant differences were identified between the population or infection characteristics of the 2 groups of dogs.Conclusions and Clinical Importance Escherichia coli isolated from canine urinary tracts are frequently capable of forming biofilms. Because no reliable clinical features allowed exclusion of biofilm formation, the potential for biofilm formation should be considered whenever E. coli UTI is diagnosed. The association of antibiotic resistance and biofilm potential may affect treatment of UTIs, but additional investigation is warranted.

Biofilm Formation and β-Lactamase Production in Burn Isolates of Pseudomonas aeruginosa.

Background:Pseudomonas aeruginosa is an important nosocomial pathogen characterized by its innate resistance to multiple antimicrobial agents. Plasmid-mediated drug resistance also occurs by the production of extended-spectrum β-lactamases (ESBL), metallo β-lactamases (MBL), and AmpC β-lactamases. Another important factor for establishment of chronic infections by P. aeruginosa is biofilm formation mediated by the psl gene cluster.Objectives:The aim of this study was to evaluate biofilm formation and presence of the pslA gene in burn isolates of P. aeruginosa as well as the association of antibiotic resistance, MBL, ESBL and AmpC β-lactamase production with biofilm formation among the isolates.Materials and Methods:Sixty-two burn isolates of P. aeruginosa were obtained from Shahid Motahari Hospital in Tehran from August to October 2011. Antibiotic susceptibility was determined by the disc diffusion assay. MBL, AmpC and ESBL production were screened using the double disc synergy test, AmpC disc test and combined disc diffusion assay, respectively. The potential to form biofilm was measured using the microtiter plate assay and pslA gene was detected using specific primers and PCR.Results:Biofilm formation was observed in 43.5% of the isolates, of which 66.7% produced strong and 33.3% formed weak biofilms. All biofilm-positive and 14.2% of biofilm-negative isolates harbored the pslA gene. MBL, AmpC and ESBL production were significantly higher in the biofilm-positive isolates (70.3%, 62.9% and 33.3%, respectively) compared to the biofilm-negative strains (31.4%, 34.2% and 20%, respectively). Overall, 19 isolates (30.6%) co-produced MBL and AmpC, among which the majority were biofilm-positive (63.1%). Finally, four isolates (6.4%) had all three enzymes, of which 3 (75%) produced biofilm.Conclusions:Biofilm formation (both strong and weak) strongly correlated with pslA gene carriage. Biofilm formation also correlated with MBL and AmpC β-lactamase production. More importantly, multiple-β-lactamase phenotype was associated with formation of strong biofilms.

Epidemiology and pattern of antibiotic resistance in Helicobacter pylori: scenario from Saudi Arabia.

Helicobacter pylori is recognized as a major cause of gastritis, peptic ulcer, gastric cancer, and mucosa-associated lymphoma. Infection with this gram-negative microaerophile has been treated using combination of antibiotics and proton pump inhibitors for different gastrointestinal diseases. The most commonly used treatment is triple therapy which consists of administration of a proton pump inhibitor, clarithromycin, and amoxicillin. Many factors contribute to treatment failure, but one of the main reasons is development of bacterial antibiotic resistance. The percent prevalence of antibiotic resistance varies among different countries; it appears to be partly determined by the geographic factors and its ability to undergo frequent homologous recombination. The aim of this paper is to review the prevalence of H. pylori infection, association of clinical outcomes with H. pylori genotypes, and current status of antibiotic resistance in H. pylori in Saudi Arabia. It also discusses the different alternative approaches for the treatment of H. pylori using antibiotics. In addition, association of antibiotic resistance with H. pylori virulent genotypes in Saudi population and its underlying resistance mechanism will also be discussed.

Association of Antibiotic Resistance in Agricultural Escherichia coli Isolates with Attachment to Quartz

Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance in agricultural isolates. We evaluated 203 Escherichia coli isolates collected from swine facilities for attachment to quartz, resistance to 13 antibiotics, and the presence of genes encoding 13 attachment factors. The genes encoding type I, EcpA, P pili, and Ag43 were detected, though none was significantly related to attachment. Quartz attachment was positively and significantly (P < 0.0038) related to combined resistance to amoxicillin/streptomycin/tetracycline/sulfamethazine/tylosin/chlortetracycline and negatively and significantly (P < 0.0038) related to combined resistance to nalidixic acid/kanamycin/neomycin. These results provide clear evidence for a link between antibiotic resistance and attachment to quartz in agricultural isolates. We propose that this may be due to encoding by the responsible genes on a mobile genetic element. Further exploration of the relationship between antibiotic resistance and attachment to environmental particles will improve the understanding and modeling of environmental transport processes, with the goal of preventing human exposure to antibiotic-resistant or virulent microorganisms.

Association of antibiotic resistance and higher internalization activity in resistant Helicobacter pylori isolates

Helicobacter pylori resistance to antibiotics is the main factor for therapy failure, while other features remain largely unknown. The aims of this study are to investigate the relationship of antibiotic resistance and in vitro internalization activity between cure and failure isolates and to determine whether failures are associated with persistence of the same predominant strain. Fifty-three isolates from forty-seven patients (cure group, n = 31; failure group, n = 16) receiving one of two lansoprazole-based therapies before and/or after therapy were investigated. Antibiotic susceptibility was determined by Etest. Genotyping was determined by cagA, babA, vacA and RAPD analyses. Target cells of internalization assay were AGS cells. Five of six paired pre- and post-treatment isolates had the same predominant genetic profiles and exhibited similarly high internalization activities. The A2143G point mutation of the 23S rRNA gene conferred clarithromycin resistance. Moreover, increased antibiotic resistance after therapy was found for these five cases. Pre-treatment isolates from the failure group (n = 11) had higher level of internalization activity than those from the cure group (n = 31) (P = 0.00005). Antibiotic-resistant strains were significantly associated with higher internalization activity than were susceptible strains (metronidazole, P < 0.005; clarithromycin, P < 0.005). Our results suggest that resistant H. pylori strains are associated with antibiotic resistance and superior internalization activity, protecting them against antibiotic treatment.