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Background: Infectious diabetic foot ulcers (IDFU) are a widespread health issue that affects people all over the world. IDFU, like other medical disorders, can have negative implications if drug resistance develops. Clinicians will be able to choose the optimal antibiotics to treat impacted patients based on the antibiotic susceptibility pattern of bacterial strains. In this project, we attempted to evaluate the levels of extended-spectrum beta-lactamase (ESBL), carbapenemase, and MRSA in patients with diabetic foot ulcers. Methods: A sterile swab was used to collect a sample from the leg ulcer, while a sterile needle was used to collect the aspirated pus. Bacteria identification and antibiotic susceptibility tests are carried out based on conventional bacterial culture. The double-disc inactivation method and modified carbapenem (meropenem) were used to screen the production of ESBL and carbapenemase. Results: Of the 76 isolates tested, 53.9% (41/76) were phenotypically ESBL producers. K. pneumoniae 75% (6/8), Acinetobacter species 75% (9/12), Serratia species 75% (3/4), Pseudomonas species 64.3% (14/9), E. coli 57.8% (11/19), Citrobacter species 50% (2/4) and Proteus mirabilis 25% (1/4) had the highest frequency of ESBL production. Of the 68 GNB isolates tested, 27.9% (19/68) were carbapenemase-producing organisms. K. pneumoniae 62.5% (5/8), Serratia 50% (3/6), Acinetobacter species 40% (4/10), Pseudomonas species 23.5% (4/17) and E. coli 15.8% (3/19) are the top five major carbapenemase producers. In this study, 32 isolates of Staphylococcus aureus were tested for methicillin resistance. Among them, 81.3% (26/32) were methicillin-resistant Staphylococcus aureus (MRSA), and 18.7% (6/32) of the remaining isolates were methicillin-sensitive Staphylococcus aureus (MSSA). Conclusion: The result draws attention to the management of diabetic foot ulcer infections based on the results of microbiological analysis and drug susceptibility testing. [ABSTRACT FROM AUTHOR]

Metallo-β-lactamase-producing Pseudomonas aeruginosa (MPPA) is an important nosocomial pathogen that shows resistance to all β-lactam antibiotics except monobactams. There are various types of metallo-β-lactamases (MBLs) in carbapenem-resistant P. aeruginosa including Imipenemase (IMP), Verona integron-encoded metallo-β-lactamase (VIM), Sao Paulo metallo-β-lactamase (SPM), Germany imipenemase (GIM), New Delhi metallo-β-lactamase (NDM), Florence imipenemase (FIM). Each MBL gene is located on specific genetic elements including integrons, transposons, plasmids, or on the chromosome, in which they carry genes encoding determinants of resistance to carbapenems and other antibiotics, conferring multidrug resistance to P. aeruginosa. In addition, these genetic elements are transferable to other Gram-negative species, increasing the antimicrobial resistance rate and complicating the treatment of infected patients. Therefore, it is essential to understand the epidemiology, resistance mechanism, and molecular characteristics of MPPA for infection control and prevention of a possible global health crisis. Here, we highlight the characteristics of MPPA. [ABSTRACT FROM AUTHOR]

Background: Extended spectrum ß-lactamases (ESBLs) represent a major group of lactamases responsible for resistance, mostly produced by gram-negative bacteria, to newer generations of ß-lactam drugs currently being identified in large numbers worldwide. The present study was undertaken to see the frequency of ESBL producing Pseudomonas spp. isolated from six hundred clinical specimens (wound, pus, aural, urine, sputum, throat and other swabs) collected over a period of three years from two tertiary care hospitals in Bangladesh. Findings: Aerobic bacterial culture was performed on aseptically collected swabs and only growth of Pseudomonas was considered for further species identification and ESBL production along with serotyping of Pseudomonas aeruginosa. Antimicrobial susceptibility testing was carried out using the Kirby-Bauer agar diffusion method and ESBL production was detected on Mueller Hinton agar by double-disk synergy technique using Amoxicillin-Clavulanic acid with Ceftazidime, Cefotaxime, Ceftriaxone and Aztreonam. Culture yielded 120 Pseudomonas spp. and 82 of them were biochemically characterized for species. Pseudomonas aeruginosa was found to be the predominant (90.2%) species. Of 82 isolates tested for ESBL, 31 (37.8%) were ESBL positive with 29 (93.5%) as Pseudomonas aeruginosa, the remaining 2 (6.5%) were Stenotrophomonas maltophilia and Ralstonia pickettii. Antibiogram revealed Imipenem as the most effective drug (93.3%) among all antimicrobials used against Pseudomonas spp. followed by Aminoglycosides (63.7%). Conclusion: ESBL producing Pseudomonas spp. was found to be a frequent isolate from two tertiary care hospitals in Bangladesh, showing limited susceptibility to antimicrobials and decreased susceptibility to Imipenem in particular, which is a matter of great concern. [ABSTRACT FROM AUTHOR]

Twenty-nine IMP-type ββ-lactamases (IMPs) have been identified in at least 26 species of clinically important Gram-negative bacilli from more than 24 countries/regions. Most of blaIMP genes are harbored by class 1 integrons that are usually embedded in transposons and/or plasmids, footnoting their horizontal transfer and worldwide distribution. blaIMP genes usually co-exist with other resistance genes, such as aacA, catB, and blaOXA, resulting in multi-drug resistance. Compared to other gene cassettes, 76.3% of the blaIMP gene cassettes are located adjacent to Pc promoter of the class 1 integrons, indicating that the blaIMP genes are readily expressed in most of bacterial hosts. [ABSTRACT FROM AUTHOR]

Background: Pseudomonas aeruginosa is among the most important nosocomial bacterial infections with innate resistance to many antibiotics. This study was designed to evaluate the frequency of extended-spectrum beta-lactamase (ESBL) multidrug-resistance produced by P. aeruginosa isolated from clinical and environmental specimens in Kashan Shahid Beheshti hospital. Materials and Methods: This descriptive study was conducted on clinical isolates (n=76) of P. aeruginosa from Kashan Shahid Beheshti hospital during 2010-11. Antibiotic susceptibility testing for eight antimicrobial agents was carried out according to the clinical and laboratory standards institute (CLSI) guidelines and ESBL-producing strains were confirmed using double-disk diffusion test. MDR-isolates were defined as those resistant to three or more classes of antibiotics. Results: Among all P. aeruginosa isolates, the highest resistance was seen for piperacillin, imipenem, cefotaxime, ceftriaxone, gentamicin, ceftazidime, aztreonam and ciprofloxacin, respectively. Seven strains (9.2%) were ESBL-positive. Twenty-seven percent of the isolates were resistant to at least three classes of antibiotics; 8 out of 14 tracheal discharges; 4 out of 9 wound and 2 out of 3 blood samples were MDR. Conclusion: The study emphasizes the high frequency of MDR-P. aeruginosa in clinical and environmental specimens isolated from this hospital. Imipenem resistance in MDR-P. aeruginosa isolates is also high in this study. This calls for strict infection control measures to prevent further microbial spread. [ABSTRACT FROM AUTHOR]