Naslov (srp)

Fenotipske i genotipske karakteristike sojeva Acinetobacter baumannii izolovanih u bolnicama sekundarnog i tercijarnog nivoa u Republici Srbiji : doktorska disertacija

Autor

Luković, Bojana, 1978-, 53745417

Doprinosi

Ranin, Lazar, 1958-, 12512359
Vučković Opavski, Nataša, 1963-, 12647527
Mijač, Vera, 1972-, 12841063
Milenković, Marina, 1963-, 12630631
Kocić, Branislava, 1954-, 4547175
Šmitran, Aleksandra, 1977-, 61750793

Opis (srp)

Uvod: Poslednjih godina dolazi do dramatičnog porasta rezistencije Acinetobacter baumannii na karbapeneme i klonskog širenja karbapenem rezistentnih A. baumannii (CRAB) sojeva širom sveta. Metod: U ovoj studiji analizirani su klinički uzorci pacijenata hospitalizovanih širom Srbije tokom 2018. godine. Kriterijum za uključivanje sojeva u studiju bila je izolacija nerepetitivnih bakterija Acb kompleksa iz kliničkih uzoraka inficiranih pacijenata. A. baumannii je identifikovan detekcijom blaOXA-51 gena. Testiranje osetljivosti na antibiotike izvršeno je disk difuzionom i bujon mikrodilucionom metodom. CRAB izolati su testirani na prisustvo stečenih karbapenemaza (OXA-24, OXA-23, OXA-58, OXA-143, IMP, VIM, GIM, SPM, SIM, NDM, GES i KPC) PCR metodom i Sangerovim sekvenciranjem. Klonska povezanost kliničkih izolata ispitana je PFGE, MLST i WGS metodom. Rezultati: Od testiranih 280 bakterija Acb kompleksa njih 237 identifikovano je kao A. baumannii. Prevalencija CRAB izolata iznosila je 93,7%. Iako su izolati pokazali visoku osetljivost na kolistin (95,7%) i tigeciklin (75,1%), deset sojeva je bilo panrezistentno. Detektovani su sledeći geni koji kodiraju stečene karbapenemaze: blaOXA-24 (44,2%), blaOXA-23 (34,5%) i blaNDM-1(3,2%). PFGE je definisao šest različitih klastera. MLST analizom CRAB izolatima su dodeljena tri tipa sekvence: ST2, ST492 i ST636. WGS je ukazao na visok stepen genetičke srodnosti testiranih sojeva koji se grupišu u četri glavna klastera. Zaključak: Ova studija svedoči o visokoj prevalenciji rezistencije A. baumannii na karbapeneme. Ona je rezultat prisustva blaOXA-72, blaOXA-23 i blaNDM-1 gena među CRAB izolatima i njihove klonske propagacije u bolnicama širom Srbije.

Opis (srp)

Medicina - Molekularna medicina / Medicine- Molecular medicine Datum odbrane: 28.09.2021.

Opis (eng)

Background: The worldwide emergence and clonal spread of carbapenem-resistant Acinetobacter baumannii (CRAB) is of great concern. Methods: Non-redundant clinical samples obtained from hospitalized patients throughout Serbia were included in the multicenter study conducted in 2018. Acb complexes recovered from clinical samples obtained from inpatients with confirmed bacterial infections were further evaluated for the presence of A. baumannii. Identification to the species level was done by the detection of the blaOXA-51 gene. Susceptibility testing was done by disk diffusion and broth microdilution method. CRAB isolates were tested for the presence of acquired carbapenemases (OXA-24, OXA-23, OXA-58, OXA-143, IMP, VIM, GIM, SPM, SIM, NDM, GES and KPC) by PCR and Sanger sequencing. Clonal relatedness was assessed by PFGE, MLST and WGS. Results: Overall, A. baumannii was identified in 237 out of 280 Acb complex (84.6%). CRAB prevalence was found to be 93.7%. Although susceptibility was high for colistin (95.7%) and tigecycline (75.1%), ten isolates were classified as pandrug-resistant. The following carbapenemases-encoding genes were found: blaOXA-24 (44.2%), blaOXA-23 (34.5%) and blaNDM-1(3.2%). PFGE analysis revealed six different clusters. MLST analysis identified three STs: ST2, ST492 and ST636. WGS suggested high genetic relatedness among the tested isolates belonging to the four clusters. Conclusion: This study revealed extremely high proportions of carbapenem resistance among A. baumannii clinical isolates due to the emergence of blaOXA-72, blaOXA-23, and blaNDM-1 genes among CRAB isolates in Serbia and their clonal propagation.

Jezik

srpski

Datum

2021

Licenca

Ovo delo je licencirano pod uslovima licence
Creative Commons CC BY-NC 2.0 AT - Creative Commons Autorstvo - Nekomercijalno 2.0 Austria License.

http://creativecommons.org/licenses/by-nc/2.0/at/legalcode

Predmet

OSNO - Opšta sistematizacija naučnih oblasti, Medicinska mikrobiologija

Acinetobacter baumannii, CRAB, blaOXA-23, blaOXA-72, blaNDM-1, ST492, ST636

616.9:579.61(043.3)

OSNO - Opšta sistematizacija naučnih oblasti, Medicinska mikrobiologija

Acinetobacter baumannii, CRAB, blaOXA-23, blaOXA-72, blaNDM-1, ST492, ST636