• 한국임상수의학회지
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• 제38권5호
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• pp.225-230
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• 2021

A 4-year-old gelding Thoroughbred racehorse, which had been undergoing antibiotic therapy at a local veterinary clinic, was referred to the KRA veterinary center with a 20-day history of continuous right nasal discharge. Patient's history, endoscopic examination, and radiographic examination revealed primary maxillary sinusitis. Under sedation, surgical intervention was performed to collect samples and remove the accumulated mucopurulent exudate in the sinus. Swab samples were collected from the sinus during surgery for cytology and antimicrobial susceptibility testing. Only one type of bacteria was cultured, and molecular analyses of 16S ribosomal RNA gene sequences identified it as Staphylococcus aureus (S. aureus). The isolate was resistant to multiple antibiotics, which are frequently used in equine practice. Trimethoprim-sulfamethoxazole was chosen based on antibiotic susceptibility test, trephination, and sinus lavage using saline were applied to treat bacterial sinusitis. The clinical signs improved after 1 month and the patient resumed training. This report describes S. aureus isolated from bacterial maxillary sinusitis in a horse and its antibiotic susceptibility.

• 대한수의학회지
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• 제63권3호
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• pp.29.1-29.5
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• 2023

An adult raccoon dog with extensive, deep, and contaminated wounds on the right hip and multiple fractures was rescued. The open wound was managed daily by debridement and flushing for 3 weeks. Modified active drainage was then performed, and antibiotics administered according to the antibiotic susceptibility test. After 2 weeks, the exudate disappeared and the drain was removed. After monitoring for 1 month, the animal was released in to the wild. This case shows that even if infection remains, rapid wound repair is possible if appropriate antibiotic selection through regular examination and active drainage are combined.

• 한국미생물·생명공학회지
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• 제50권1호
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• pp.147-156
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• 2022

Urinary tract infections (UTIs) are one of the most common infections in different age groups, including children. Bacteria are the main etiological agents of UTIs. The aim of the present study was to isolate, identify, and determine the antibiotic susceptibility of bacteria isolated from children with UTIs from Baghdad, Iraq. Three hundred and two urine samples were collected from children aged 6 months to 12 years. The samples were cultured on blood agar and MacConkey agar. The selected colonies were subjected to biochemical tests and antibiotic susceptibility analysis using the Vitek^® 2 Compact automated microbial identification system. In this sample, 299 bacteria were identified, of which, 267 were gram-negative bacteria, and 32 were gram-positive bacteria. Escherichia coli (56%) was the most commonly isolated gram-negative bacteria, followed by Pseudomonas aeruginosa (14%), Enterobacter spp. (10.48%), Klebsiella pneumoniae (9.36%), Proteus spp. (7.8%), Acinetobacter baumannii (1.5%), and Morganella morganii (0.37%). Enterococcus faecalis (62.5%) was the most commonly detected gram-positive bacteria, followed by Staphylococcus aureus (37.5%). E. coli and P. aeruginosa were the most antibiotic-resistant bacteria. Among the tested antibiotics, meropenem showed 100% sensitivity, followed by imipenem (97.4%), amikacin (91.8%), and tobramycin (83.5%). In contrast, the high frequencies of resistance were observed with cefixime (93.2%), cefotaxime (78.7%), and ceftriaxone/cefotaxime (71.2%). In conclusion, carbapenems and aminoglycosides are highly recommended for the empirical treatment of UTIs, while, Quinolones, penicillins, and cephalosporins are not suggested. Frequent antibiotics susceptibility testing are warranted to determine the resistance pattern of UTI bacteria.

• 한국어병학회지
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• 제28권2호
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• pp.71-78
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• 2015

In this study, we conducted to the development of a rapid antimicrobial susceptibility test method using WST-1 which is known to water-soluble tetrazolium salt, in order to rapidly response against bacterial diseases in fish. Eight of antibiotics which are permissioned for marine organism from government were used to rapid antimicrobial susceptibility testing using the WST-1. As a result, a similar tendency was verified compare to conventional antibiotic susceptibility test results. Generally, the antibiotic susceptibility test method required about 3 days (72 hours) for determine the effective antibiotics, however, we have confirmed that the our method using WST-1 was required at least 36 hours in this study. Consequentially, our method will contribute to development of rapid antimicrobial susceptibility testing for bacterial diseases in fish.

• Journal of Microbiology and Biotechnology
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• 제10권5호
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• pp.685-689
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• 2000

Due to the uncultivable nature of Mycobacterium leprae in vitro, the fast, easy, and accurate measurement of the antimicrobial drug susceptibility of this microbe has been difficult. Conventional methods for such testing are subjective, cumbersome, and expensive in some cases. Here, the utility of a reverse transcriptase-PCR (RT-PCR)-based assay for testing was examined and compared with a Buddmeyer-type radiorespirometric assay. The susceptibility of M. leprae to rifampin was determined by probing the presence of M.leprae-specific 18 kDa gene mRNA in M. leprae-infected IC-21 macrophage cells after drug treatment. The results showed that, as the refampin concentration was increased, the 360-bp cDNA products generated by the RT-PCR-based assay decreased in a dose-dependent manner as in the drug susceptibility observed in the Buddmeyer-type assay. The drug susceptibility testing of M. leprae by the RT-PCR based assay was found to be not only faster but also nearly $10^4$-fold more sensitive than the Buddmeyer-type assay. Moreover, it was also found that, unlike the RT-PCR based assay, the same testing by a DNA-PCR resulted in no differences in the 360-bp signal, regardless of the rifampin concentrations used. Accordingly, these results demonstrated that the drug susceptibility of M. leprae can be determined effectively by an RT-PCR-based assay, thereby providing a new, fast, and sensitive testing method.

• 대한임상검사과학회지
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• 제45권1호
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• pp.21-25
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• 2013

Acinetobacter baumannii is an aerobic, gram-negative and glucose-non-fermenting bacterium, which has emerged as a serious opportunistic pathogen. Many clinical microbiology laboratories use the Vitek 2 system for the routine antimicrobial susceptibility testing process, including testing on A. baumannii isolates. However, in case of amikacin, it is now recommended to perform additional antimicrobial susceptibility testing for A. baumannii strains due to the relatively lower minimum inhibitory concentration (MIC) in the Vitek 2 system compared to conventional reference methods. In our study, we assessed MIC for amikacin susceptibility testing of A. baumannii isolates in the Vitek 2 system, the agar dilution, Etest, and disk diffusion method. We collected 40 gentamicin-resistant, A. baumannii strains (amikacin MIC by Vitek 2:${\leq}2{\mu}g/mL$, 2 isolates; $4{\mu}g/mL$, 34 isolates; $8{\mu}g/mL$, 4 isolates) from a University hospital and compared the Vitek 2 system to other reference methods for testing susceptibility to amikacin. The Vitek 2 system showed major errors in all of the 40 isolates, yielding a low MIC. The results of our study strongly suggested that the Vitek 2 system was not a reliable method to test the MICs of gentamicin; ranging from ${\geq}16{\mu}g/mL$ for amikacin susceptibility. Other tests, such as agar dilution, Etest, or disk diffusion methods, should be paralleled to determine the MIC of amikacin in A. baumannii.

• 한국연초학회지
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• 제18권1호
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• pp.54-59
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• 1996

Erwinia carotovora subsp. Carotovora (Ecc), a pathogen of tobacco hollow stalk disease, was isolated for testing susceptibility to streptomycin from diseased plants in burley tobacco growing area. Of 157 isolates tested, 17 isolates (108%) were resistant to the antibiotic at the antibiotic from field soils, which streptomycin had been used continuously for three years for control of the disease was three times higher than those of non-used. There was no difference in virulence and generation time between streptomycin-sensitive and resistant strains.

• 대한임상검사과학회지
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• 제46권4호
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• pp.136-139
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• 2014

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the severe nosocomial infectious agents. The traditional diagnostic methods including biochemical test, antibiotic susceptibility test and PCR amplification are time consuming and require much work. The Surface enhanced Raman spectroscopy (SERS) biosensor is a rapid and powerful tool for analyzing the chemical composition within a single living cell. To identify the biochemical and genetic characterization of clinical MRSA, all isolates from patients were performed with VITEK2 gram positive (GP) bacterial identification and Antibiotic Susceptibility Testing (AST). Virulence genes of MRSA also were identified by DNA based PCR using specific primers. All isolates, which were placed on a gold coated nanochip, were analyzed by a confocal Raman microscopy system. All isolates were identified as S. aureus by biochemical tests. MRSA, which exhibited antibiotic resistance, demonstrated to be positive gene expression of both femA and mecA. Furthermore, Raman shift of S. aureus and MRSA (n=20) was perfectly distinguished by a confocal Raman microscopy system. This novel technique explained that a SERS based confocal Raman microscopy system can selectively isolate MRSA from non-MRSA. The study recommends the SERS technique as a rapid and sensitive method to detect antibiotic resistant S. aureus in a single cell level.

• Pediatric Infection and Vaccine
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• 제27권3호
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• pp.147-157
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• 2020

목적: 최근 β-lactam 계 항생제에 대한 내성을 보이는 Haemophilus influenzae가 증가하고 있다. 본 연구는 최근 5년간 서울아산병원 어린이 병원에서 분리된 H. influenzae 균주의 항생제 내성 양상을 분석하고자 한다. 방법: 2014년 3월부터 2019년 4월까지 서울아산병원 어린이병원을 내원한 18세 미만의 소아청소년 환자의 임상 검체에서 분리된 H. influenzae 균주를 대상으로 항생제 내성 양상을 분석하였다. 결과: 최근 5년간 총 69례의 H. influenzae가 분리되었으며 이들 환자의 연령 중앙값은 5.0 (2.8-8.6)세였다. 총 69례 중 3례(4.3%)가 혈액 배양에서 분리되었으며, 66례(95.7%)가 비침습성 균주로서 대부분 호흡기 검체(59례)에서 분리되었다. 항생제 감수성 분포는 ampicillin (AMP) 감수성/amoxicillin-clavulanate (AMC) 감수성 균주 15례(21.7%), AMP 내성/AMC 감수성 21례(30.4%), AMP 내성/AMC 내성 33례(47.8%)였으며, 최근 5년에 걸쳐 AMP 내성/AMC 내성 균주는 지속적으로 증가하는 경향을 보였다 (2014-2015: 42.1% [8/19], 2016-2017: 46.4% [13/28], 2018-2019: 54.5% [12/22], P for trend=0.342). 2014-2015년에 비해 2018-2019년 기간에는 cefuroxime과 ceftriaxone에 대한 내성률은 각각 31.6%에서 77.3% 및 0.0% 에서 59.1% 로 유의하게 증가하였다(P for trend 0.003 및 <0.001). 결론: 최근 국내의 3차 의료기관에 입원한 소아에서 분리되는 H. influenzae 균주는 AMP및 AMC에 대해 모두 내성인 경우가 흔하며, cefuroxime 및 ceftriaxone 에 대한 내성률이 유의하게 증가하였다. 이러한 균주의 내성 기전 분석과 함께 이의 출현과 확산을 최소화하기 위한 노력이 필수적이다.

• Journal of Microbiology and Biotechnology
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• 제33권5호
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• pp.668-679
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• 2023

Edwardsiella tarda is one of the most significant fish pathogens, causes edwardsiellosis in a variety of freshwater fish species, and its antibiotic resistance against multiple drugs has made it a health risk worldwide. In this study, we aimed to investigate the antibiotic resistance (ABR) genes of E. tarda and establish its antibiotic susceptibility. Thus, 540 fish (299 Oreochromis niloticus, 138 O. mossambicus, and 103 O. aureus) were collected randomly from twelve fish farms in three districts of Punjab in Pakistan. E. tarda was recovered from 147 fish showing symptoms of exophthalmia, hemorrhages, skin depigmentation, ascites, and bacteria-filled nodules in enlarged liver and kidney. Antimicrobial susceptibility testing proved chloramphenicol, ciprofloxacin, and streptomycin effective, but amoxicillin, erythromycin, and flumequine ineffective in controlling edwardsiellosis. Maximum occurrence of qnrA, blaTEM, and sul3 genes of E. tarda was detected in 45% in the liver, 58%, and 42% respectively in the intestine; 46.5%, 67.2%, and 55.9% respectively in O. niloticus; 24%, 36%, and 23% respectively in summer with respect to fish organs, species, and season, respectively. Motility, H₂S, indole, methyl red, and glucose tests gave positive results. Overall, E. tarda infected 27.2% of fish, which ultimately caused 7.69% mortality. The Chi-squared test of independence showed a significant difference in the occurrence of ABR genes of E. tarda with respect to sampling sites. In conclusion, the misuse of antibacterial agents has led to the emergence of ABR genes in E. tarda, which in association with high temperatures cause multiple abnormalities in infected fish and ultimately resulting in massive mortality.