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Kahin MA, Mohamed AH, Mohomed AA, Hassan MA, Gebremeskel HF, Kebede IA. Occurrence, antibiotic resistance profiles and associated risk factors of Klebsiella pneumoniae in poultry farms in selected districts of Somalia Reginal State, Ethiopia. BMC Microbiol 2024; 24:137. [PMID: 38658825 PMCID: PMC11040913 DOI: 10.1186/s12866-024-03298-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 04/08/2024] [Indexed: 04/26/2024] Open
Abstract
BACKGROUND Klebsiella pneumoniae is an opportunistic infection that causes production losses and death in the chicken industry. A cross-sectional study was conducted on exotic chicken breeds reared at the Jigjiga poultry farm from November 2022 to May 2023 to estimate the occurrence, associated risk factors, and antimicrobial susceptibility profiles of Klebsiella pneumoniae. The chickens were selected using systematic random sampling techniques. A total of 384 cloacal swabs were collected aseptically and transported to the laboratory for analysis. For statistical analysis, STATA® version 14.0 statistical software was used. RESULTS From 384 examined faecal samples, 258 (67.2%) prevalences of Klebsiella pneumoniae were found. Furthermore, the association of the study's risk factors with the prevalence of Klebsiella pneumoniae was explored, and no statistically significant association was identified between sex and age. Nonetheless, relative prevalence at the age level was higher in chickens aged 12 months (67.6%) and Sasso breeds (90.0%). Similarly, male chickens and those raised for meat and egg production had a high prevalence rate of 72.5 and 75.8%, respectively. A total of 30 isolated Klebsiella pneumoniae colonies were tested in vitro for antibiotic sensitivity for six drugs, and it was shown that Klebsiella pneumoniae is moderately sensitive to Penicillin G (43.3%) while having higher resistance to Oxytetracycline (80.0%). CONCLUSIONS The current findings revealed that the research area had the highest prevalence of Klebsiella pneumoniae, and the isolates were resistant to commonly used drugs in the study area. Thus, a long-term intervention plan, thorough research to determine a nationwide status, as well as further multi-drug resistance patterns and molecular characterization, were urged.
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Affiliation(s)
| | | | | | | | | | - Isayas Asefa Kebede
- School of Veterinary Medicine, Ambo University, P. O. Box 19, Guder, Ethiopia.
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Hosny RA, El-Badiea ZA, Elmasry DMA, Fadel MA. Efficacy of ceftiofur N-acyl homoserine lactonase niosome in the treatment of multi-resistant Klebsiella pneumoniae in broilers. Vet Res Commun 2023; 47:2083-2100. [PMID: 37430152 DOI: 10.1007/s11259-023-10161-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 06/26/2023] [Indexed: 07/12/2023]
Abstract
In this study, the efficiency of the ceftiofur N-acyl homoserine lactonase niosome against multi-resistant Klebsiella pneumoniae in broilers was evaluated. Fifty-six K. pneumoniae isolates previously recovered from different poultry and environmental samples were screened for the ahlK gene. The lactonase enzyme was extracted from eight quorum-quenching isolates. The niosome was formulated, characterized, and tested for minimal inhibitory concentration (MIC) and cytotoxicity. Fourteen-day-old chicks were assigned to six groups: groups Ӏ and П served as negative and positive controls, receiving saline and K. pneumoniae solutions, respectively. In groups Ш and IV, ceftiofur and niosome were administrated intramuscularly at a dose of 10 mg/kg body weight for five consecutive days, while groups V and VI received the injections following the K. pneumoniae challenge. Signs, mortality, and gross lesions were recorded. Tracheal swabs were collected from groups П, V, and VI for counting K. pneumoniae. Pharmacokinetic parameters were evaluated in four treated groups at nine-time points. The niosome was spherical and 56.5 ± 4.41 nm in size. The viability of Vero cells was unaffected up to 5 × MIC (2.4 gml-1). The niosome-treated challenged group showed mild signs and lesions with lower mortality and colony count than the positive control group. The maximum ceftiofur serum concentrations in treated groups were observed 2 h following administration. The elimination half-life in niosome-treated groups was longer than that reported in ceftiofur-treated groups. This is the first report of the administration of N-acyl homoserine lactonase for the control of multi-resistant K. pneumoniae infections in poultry.
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Affiliation(s)
- Reham A Hosny
- Reference Laboratory for Veterinary Quality Control On Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza, Egypt.
| | - Zeinab A El-Badiea
- Reference Laboratory for Veterinary Quality Control On Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza, Egypt
| | - Dalia M A Elmasry
- Nanomaterials Research and Synthesis Unit, Animal Health Research Institute, Agriculture Research Center, Giza, Egypt
| | - Mai A Fadel
- Pharmacology and Pyrogen Unit, Department of Chemistry, Toxicology, and Feed Deficiency, Animal Health Research Institute, Agriculture Research Center, Giza, Egypt
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Moftian N, Rezaei-Hachesu P, Arab-Zozani M, Samad-Soltani T, Esfandiari A, Tabib MS, Mirnia K. Prevalence of gram-negative bacteria and their antibiotic resistance in neonatal sepsis in Iran: a systematic review and meta-analysis. BMC Infect Dis 2023; 23:534. [PMID: 37582726 PMCID: PMC10426195 DOI: 10.1186/s12879-023-08508-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 08/03/2023] [Indexed: 08/17/2023] Open
Abstract
BACKGROUND Neonatal sepsis, particularly gram-negative (GN) bacteria-induced, is a significant cause of morbidity and mortality in newborns. Healthcare professionals find this issue challenging because of antibiotic resistance. This study aims to combine findings to identify the prevalence of GN bacteria and their antibiotic resistance in Iranian neonates with sepsis. METHODS This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The literature search was performed through international databases, including (PubMed/MEDLINE, EMBASE, Scopus, and Web of Science), Iranian local databases (Magiran, Iranmedex, Irandoc, Scimed, and SID), and the first 100 records of Google Scholar. Analytical cross-sectional study checklist from the Joanna Briggs Institute (JBI) was used for the quality assessment of included studies. Comprehensive Meta-Analysis Software Version 2 was used to conduct the meta-analysis. The between-study heterogeneity was investigated by I2 statistics. RESULTS The prevalence of GN bacteria was estimated to be 53.6% [95% CI: 45.9- 61.1: P = 0.362] in Iranian neonates with sepsis, based on 31 studies with a sample size of 104,566. klebsiella pneumoniae (K.pneumonia) (23.2% [95% CI: 17.5-30.0, P < 0.001]) followed by Escherichia coli (E.coli) (13.5% [95% CI: 9.4-18.9, P < 0.001]) were more prevalent among GN bacteria. The highest resistance in K.pneumoniae was observed in Cefixime (80.6%, [95% CI: 56.3-93.1, P = 0.018]). E.coli showed greater resistance to Ampicillin (61.8%, [95% CI: 44.2-76.5, P = 0.188]. The prevalence of GN bacteria in Iranian neonates with sepsis has a decreasing trend based on the year, as shown by a meta-regression model (P < 0.0004). CONCLUSION GN pathogens, particularly K.pneumoniae, and E.coli, are the leading cause of neonatal sepsis in Iran. GN bacteria showed the highest resistance to Third-generation cephalosporin and Aminoglycosides.
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Affiliation(s)
- Nazila Moftian
- Department of Health Information Technology, Faculty of Management and Medical Informatics, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Peyman Rezaei-Hachesu
- Department of Health Information Technology, Faculty of Management and Medical Informatics, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Morteza Arab-Zozani
- Social Determinants of Health Research Center, Birjand University of Medical Sciences, Birjand, Iran
| | - Taha Samad-Soltani
- Department of Health Information Technology, Faculty of Management and Medical Informatics, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Atefeh Esfandiari
- Department of Health Policy & Management, Faculty of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran
| | - Mohammad Saleh Tabib
- Department of Pediatrics, School of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran
| | - Kayvan Mirnia
- Children Medical Center, Tehran University of Medical Sciences, Tehran Province, Keshavarz Blvd, P94M+85P, Tehran, 14197 33151, Iran.
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Zong S, Xu D, Zheng X, Zaeim D, Wang P, Han J, Qu D. The diversity in antimicrobial resistance of MDR Enterobacteriaceae among Chinese broiler and laying farms and two mcr-1 positive plasmids revealed their resistance-transmission risk. Front Microbiol 2022; 13:912652. [PMID: 35992687 PMCID: PMC9387725 DOI: 10.3389/fmicb.2022.912652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
This research aimed to investigate the microbial composition and diversity of antimicrobial resistance genes (ARGs) found in Chinese broiler and layer family poultry farms. We focused on the differences in resistance phenotypes and genotypes of multidrug-resistant Enterobacteriaceae (MDRE) isolated from the two farming environments and the existence and transmissibility of colistin resistance gene mcr-1. Metagenomic analysis showed that Firmicutes and Bacteroides were the dominant bacteria in broiler and layer farms. Many aminoglycoside and tetracycline resistance genes were accumulated in these environments, and their absolute abundance was higher in broiler than in layer farms. A total of 526 MDRE were isolated with a similar distribution in both farms. The results of the K-B test showed that the resistance rate to seven antimicrobials including polymyxin B and meropenem in broiler poultry farms was significantly higher than that in layer poultry farms (P ≤ 0.05). PCR screening results revealed that the detection rates of mcr-1, aph(3’)Ia, aadA2, blaoxa–1, blaCTX–M, fosB, qnrD, sul1, tetA, and catA1 in broiler source MDRE were significantly higher than those in layers (P ≤0.05). A chimeric plasmid p20432-mcr which carried the novel integron In1866 was isolated from broiler source MDRE. The high frequency of conjugation (10–1 to 10–3) and a wide range of hosts made p20432-mcr likely to play an essential role in the high detection rate of mcr-1, aph(3’)-Ia, and aadA2 in broiler farms. These findings will help optimize disinfection and improve antimicrobial-resistant bacteria surveillance programs in poultry farms, especially broilers.
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Affiliation(s)
- Shuaizhou Zong
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Dingting Xu
- The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xiner Zheng
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Davood Zaeim
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Peng Wang
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Jianzhong Han
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Daofeng Qu
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
- *Correspondence: Daofeng Qu,
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Detection of Quorum Sensing N-Acyl-Homoserine Lactone Molecules Produced by Different Resistant Klebsiella pneumoniae Isolates Recovered from Poultry and Different Environmental Niches. Appl Biochem Biotechnol 2021; 193:3351-3370. [PMID: 34196919 DOI: 10.1007/s12010-021-03605-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 06/21/2021] [Indexed: 10/21/2022]
Abstract
This study aimed to detect and identify the N-acyl-homoserine lactones molecules (AHLs) produced by different resistant Klebsiella pneumoniae isolates recovered from poultry and environmental samples using a modified validated high-performance liquid chromatography method. A total of 56 K. pneumoniae isolates were recovered, investigated for their antibiotic susceptibility, and screened for AHLs production using the Agrobacterium tumefaciens NTL4 biosensor system and a validated high-performance liquid chromatography method. The results revealed the detection of different short- and long-chain AHLs molecules among 39 K. pneumoniae isolates recovered from poultry and environmental samples. All environmental isolates produced nine peaks with retention times for C4-HSL, C6-HSL, C12-HSL, C8-HSL, C14-HSL, C8-oxo-HSL, C10-HSL, C6-oxo-HSL, and C7-HSL. The most quantifiable AHL signal molecules in poultry isolates were C4-HSL, C6-HSL, and C12-HSL. No statistical correlation between the AHL-producing ability of K. pneumoniae isolates and antibiotic resistance was reported. To the best of our knowledge, this study provides the first detailed report on the detection and identification of AHLs in K. pneumoniae isolates recovered from poultry and environmental samples. Furthermore, it provides a new insight available tool other than LC-MS/MS for detection and identification of AHL molecules.
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Elmonir W, Abd El-Aziz NK, Tartor YH, Moustafa SM, Abo Remela EM, Eissa R, Saad HA, Tawab AA. Emergence of Colistin and Carbapenem Resistance in Extended-Spectrum β-Lactamase Producing Klebsiella pneumoniae Isolated from Chickens and Humans in Egypt. BIOLOGY 2021; 10:biology10050373. [PMID: 33926062 PMCID: PMC8146310 DOI: 10.3390/biology10050373] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/21/2021] [Accepted: 04/22/2021] [Indexed: 12/26/2022]
Abstract
Simple Summary Carbapenems and colistin are reserved as the last-resort treatments of multidrug-resistant (MDR) infections in humans. Consequently, the emergence of carbapenem and colistin-resistant Klebsiella pneumoniae (K. pneumoniae) in poultry, contact workers and hospitalized patients is of grave concern for therapeutic options, and no data are available supporting this assumption on a regional or countrywide scale. We investigated the frequency and typing of extended-spectrum β-lactamase (ESBL) and carbapenemase-producing K. pneumoniae (ESBLK and CPK) in hospitalized patients, chickens from 10 poultry farms and their environment (water, food and litter) and farm workers in Egypt. All isolates from patients (13/90, 14.4%), workers (5/22, 22.7%), chickens (9/100, 9%) and the environment (10/60, 16.7%) harbored a single or multiple β-lactamase genes, blaSHV, blaTEM, blaCTX-M1 and blaOXA-1, often in combination with carbapenemase genes (blaVIM, blaNDM-1 or blaIMP; 45.9%), the mcr-1 gene (18.9%) or both (13.5%). Enterobacterial repetitive intergenic consensus (ERIC)-PCR genotyping highlighted potential inter and intraspecies clonal dissemination in the study area. The increased frequency and genetic relatedness of ESBLK and CPK from chickens and humans pose a public health threat that urges more prudent use of antimicrobials in chicken farms to avoid the propagation and expansion of both ESBLK and CPK from the chicken sources to humans. Abstract This study investigated the frequency of carbapenem and colistin resistance in ESBL-producing K. pneumoniae (ESBLK) isolates recovered from chickens and their environment, contact farm workers and hospitalized patients in Egypt. Further, the phenotypic and genotypic relationships between the community and hospital-acquired K. pneumoniae isolates in the same geographical area were investigated. From 272 total samples, 37 (13.6%) K. pneumoniae isolates were identified, of which 20 (54.1%) were hypervirulent. All isolates (100%) were multidrug-resistant (MDR) with multiple antibiotic resistance (MAR) indices ranging from 0.19 to 0.94. Colistin-resistant isolates (18.9%) displayed colistin MIC values >2 μg/mL, all harbored the mcr-1 gene. All isolates from patients (13/90, 14.4%), workers (5/22, 22.7%), chickens (9/100, 9%) and the environment (10/60, 16.7%) harbored a single or multiple β-lactamase genes, blaSHV, blaTEM, blaCTX-M1 and blaOXA-1, often in combination with carbapenemase genes (blaVIM, blaNDM-1 or blaIMP; 45.9%), the mcr-1 gene (18.9%) or both (13.5%). Enterobacterial repetitive intergenic consensus (ERIC)–PCR genotyping revealed 24 distinct ERIC types (ETs) with a discrimination index of 0.961. Six ETs showed clusters of identical isolates from chicken and human sources. The increased frequency and genetic relatedness of ESBLK and carbapenemase-producing K. pneumoniae (CPK) from chickens and humans pose a public health threat that urge more prudent use of antimicrobials in chicken farms to avoid the propagation and expansion of both ESBLK and CPK from the chicken sources to humans.
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Affiliation(s)
- Walid Elmonir
- Department of Hygiene and Preventive Medicine (Zoonoses), Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt
| | - Norhan K Abd El-Aziz
- Department of Microbiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44511, Egypt
| | - Yasmine H Tartor
- Department of Microbiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44511, Egypt
| | - Samar M Moustafa
- Department of Zoonoses, Faculty of Veterinary Medicine, Benha University, Benha 13518, Egypt
| | - Etab M Abo Remela
- Department of Bacteriology, Mycology and Immunology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt
- Department of Biology, College of Science, Taibah University, Madina 42353, Saudi Arabia
| | - Radwa Eissa
- Department of Microbiology and Immunology, Faculty of Medicine, Tanta University, Tanta 31527, Egypt
| | - Hosam A Saad
- Department of Chemistry, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia
| | - Ahmed Abdel Tawab
- Department of Microbiology, Faculty of Medicine, Al Azhar University, Cairo 11884, Egypt
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Hardiati A, Safika S, Wibawan IWT, Indrawati A, Pasaribu FH. Isolation and detection of antibiotics resistance genes of Escherichia coli from broiler farms in Sukabumi, Indonesia. J Adv Vet Anim Res 2021; 8:84-90. [PMID: 33860017 PMCID: PMC8043354 DOI: 10.5455/javar.2021.h489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 12/06/2020] [Accepted: 12/18/2020] [Indexed: 01/12/2023] Open
Abstract
OBJECTIVE This study aimed to isolate and identify Escherichia coli from broiler samples from Sukabumi, Indonesia. Also, antibiogram studies of the isolated bacteria were carried out considering the detection of the antibiotic resistance genes. MATERIALS AND METHODS Cloaca swabs (n = 45) were collected from broilers in Sukabumi, Indonesia. Isolation and identification of E. coli were carried out according to standard bacteriological techniques and biochemical tests, followed by confirmation of the polymerase chain reaction targeting the uspA gene. Antibiotic sensitivity test, using several antibiotics [tetracycline (TE), oxytetracycline (OT), ampicillin (AMP), gentamicin (CN), nalidixic acid (NA), ciprofloxacin (CIP), enrofloxacin (ENR), chloramphenicol, and erythromycin] was carried out following the Kirby-Bauer disk diffusion method. Detection of antibiotic resistance coding genes was carried out by PCR using specific oligonucleotide primers. Statistical analysis was carried out with one-way analysis of variance. RESULTS The results showed that 55.6% (25/45) of the samples were associated with the presence of E. coli. Antibiotic sensitivity test showed that the E. coli isolates were resistant to TE (88%; 22/25), OT (88%; 22/25), AMP (100%; 25/25), CN (64%; 16/25), NA (100%; 22/25), CIP (88%; 22/25), ENR (72%; 18/25), chloramphenicol (0%; 0/25), and erythromycin (92%; 23/25). On the other hand, the antibiotic resistance coding genes were tetA (86.4%; 19/22), blaTEM (100%; 25/25), aac(3)-IV (0%; 0/16), gyrA (100%; 25/25), and ermB (13%; 3/23). It was found that chloramphenicol is markedly different from other antibiotic treatment groups. CONCLUSION Escherichia coli was successfully isolated from cloacal swabs of broiler in Sukabumi, Indonesia. The bacteria were resistant to TE, OT, AMP, CN, NA, CIP, ENR, and erythromycin. Chloramphenicol was more sensitive and effective than other antibiotics in inhibiting the growth of E. coli. The antibiotic resistance genes detected were tetA, blaTEM, gyrA, and ermB.
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Affiliation(s)
- Aprilia Hardiati
- Department of Animal Infectious Diseases and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University, Bogor, Indonesia
| | - Safika Safika
- Department of Animal Infectious Diseases and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University, Bogor, Indonesia
| | - I Wayan Teguh Wibawan
- Department of Animal Infectious Diseases and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University, Bogor, Indonesia
| | - Agustin Indrawati
- Department of Animal Infectious Diseases and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University, Bogor, Indonesia
| | - Fachriyan Hasmi Pasaribu
- Department of Animal Infectious Diseases and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University, Bogor, Indonesia
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Lenchenko E, Blumenkrants D, Sachivkina N, Shadrova N, Ibragimova A. Morphological and adhesive properties of Klebsiella pneumoniae biofilms. Vet World 2020; 13:197-200. [PMID: 32158172 PMCID: PMC7020135 DOI: 10.14202/vetworld.2020.197-200] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 12/23/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND AND AIM The study of biofilm-forming ability of Gram-negative microflora has great practical importance for assessing the effectiveness of antibiotic therapy and finding new ways to diagnose and inhibit the growth of biofilms. This is because poor penetration of antibacterial drugs into the biofilm can lead to the selection of resistant strains and has a consequence evident by the occurrence of relapse of infection in animals. This study aimed to evaluate morphological and densitometric indicators of biofilm formation as well as adhesive properties of Klebsiella pneumoniae. MATERIALS AND METHODS K. pneumoniae was cultured at 37°C for 2-144 h in vitro. The specimens for optical microscopy were prepared by fixation with a 1:1 alcohol-ether mixture for 10 min and stained with a 0.5% solution of gentian violet for 2 min, and the optical density index was evaluated at a wavelength of 490 nm. Further, the adhesive properties of the microorganisms were determined at a concentration of 1 billion/ml and a suspension of ram erythrocytes at a concentration of 100 million/ml when cultured at 37°C for 24 h. Blood smears were prepared and stained with 0.5% gentian violet. RESULTS K. pneumonia cultured at 37°C after 24 h on the meat peptone agar formed large, convex, mucous, and white colonies (d=3.0-6.0 mm). With the growth in the meat and peptone broth, uniform turbidity of the medium was observed. Analyzing the optical density indices (density, D), it was found that K. pneumoniae were good producers of biofilms (D=0.528±0.31). Data for indicators of adhesive properties of K. pneumoniae were as follows: Average adhesion index, 4.56±0.14; adhesion coefficient, 1.07±0.52; and adhesion index, 4.26±0.07. The studied bacteria had high adhesive activity. A direct correlation dependence (R=0.94) of the optical density of biofilms (D≥0.514-0.551) and AAI (4.15±0.28-4.76±0.75) was established. CONCLUSION This study has demonstrated that K. pneumoniae had high adhesive activity, was strong producer of biofilms, and the optical density of the sample exceeded the optical density of the control by more than 4 times.
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Affiliation(s)
- Ekaterina Lenchenko
- Department of Veterinary Medicine, Moscow State University of Food Production, Moscow, Russia
| | - Dmitry Blumenkrants
- Department of Veterinary Medicine, Moscow State University of Food Production, Moscow, Russia
| | - Nadezhda Sachivkina
- Department of Microbiology and Virology, Medical Institute, Peoples’ Friendship University of Russia, Moscow, Russia
| | - Nadezhda Shadrova
- Department of Veterinary Medicine, Agrarian Technological Institute, Peoples’ Friendship University of Russia, Moscow, Russia
| | - Alfia Ibragimova
- Department of Foreign Languages, Agrarian Technological Institute, Peoples’ Friendship University of Russia, Moscow, Russia
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