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BACKGROUND Pandrug-resistant (PDR) Klebsiella pneumoniae has been reported sporadically in many countries and remains rare in Brazil. OBJECTIVES This study unravelled the genetic determinants involved with the PDR background of a clinical ST11 K. pneumoniae recovered in the Brazilian Amazon Region, where K. pneumoniae genomic and epidemiological information is scarce. METHODS Kp196 was submitted to the antimicrobial susceptibility test by the disk-diffusion method and minimum inhibitory concentration (MIC) determination. The whole genome sequencing was obtained and the sequence type was determined by core genome multilocus sequence typing (cgMLST). Its intrinsic and acquired resistome was assessed by Comprehensive Antibiotic Resistance Database (CARD) and comparison with wild-type genes. FINDINGS The analyses revealed that Kp196 belonged to the pandemic ST11 and presented the PDR phenotype. Its acquired resistome was composed of a huge set of clinically relevant resistance determinants, including bla CTX-M-15 and bla NDM-1, all found in the vicinity of mobile platforms. Considering its intrinsic resistome, the multidrug resistance, especially to colistin, tigecycline and fluoroquinolones, was multifactorial and attributed to modifications (indels, missense mutations, and gene disruption) in several housekeeping genes (arnT/phoQ/mgrB/ramR/acrB/gyrA/parC/ompK35-36-37). The Kp196 intrinsic resistome was also observed in a ST11 environmental strain, although harbouring distinct acquired resistomes. CONCLUSIONS An accumulation of different resistance mechanisms regarding the intrinsic resistome accounts for a more stable resistome, strongly contributing to the Kp196 PDR phenotype.
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Objective To study the homology and clinical distribution of tigecycline-resistant Acinetobacter baumannii (A.baumannii )in a hospital.Methods Multidrug-resistant A.baumannii (MDRAB,n = 88 )from specimens from clinical departments of a hospital in 2013-2014 were collected and detected susceptibility to tigecy-cline;homology of tigecycline-resistant strains were detected by pulsed-field gel electrophoresis (PFGE),clinical characteristics and distribution of infected patients were analyzed.Results 88 patients didn’t use tigecycline before MDRAB were isolated.Of 88 MDRAB strains,4 (4.55%)were resistant to tigecycline,which were No.10,31 , 33,and 87 strains.PFGE results revealed that No.31 ,33,and 87 strains were of the same genotype,and with high homology,which distributed in three different departments;No.31 strain was detected from general intensive care unit (ICU),No.33 strain was detected from emergency ICU,although strains were detected from different depart-ments,patients were transferred before strains were isolated,and were admitted to departments of gastrointestinal surgery and emergency ICU during the same period;No.87 strain was detected from neurosurgical ICU and patient had never been transferred,the detection time was 7-8 months later than No.31 and 33 strains.No.10 strain was isolated from emergency ICU,patient was not transferred.Conclusion Of MDRAB isolated in this hospital,tigecy-cline-resistant strains are low,most strains are homologous,cross infection may be exists in different departments.