title: Microbiological and Clinical Characteristics of HypermucoviscousKlebsiella pneumoniaeIsolates Associated with Invasive Infections in China.
abstract: A distinctive syndrome caused by hypermucoviscousKlebsiella pneumoniae(HMKP) including pyogenic liver abscess (PLA) is now becoming a globally emerging disease. In the present study, 22.8% (84/369) ofK. pneumoniaeclinical isolates associated with various types of invasive infections were identified as HMKP, with 45.2% associated with PLA. Multivariate regression analysis showed that male patients with 41-50 years, PLA, diabetes mellitus, and hypertension were independent risk factors for HMKP infections. K2 (42.9%, 36/84) was the most common capsular serotype among HMKP isolates, followed by K1 (23.8%, 20/84). Seventy-five percentage of K1 HMKP isolates were associated with PLA, while K2 HMKP isolates accounted for more types of invasive infections. The positive rates ofiutA, mrkD, aerobactin, iroN, andrmpAamong HMKP isolates were significantly higher than those among non-HMKP isolates (p< 0.05). There was a correlation betweenmagA, ybtS, alls, andwcaGand K1 isolates. Interestingly,mrkDwas exclusively detected among HMKP (32.1%, 27/84) and K2 isolates (65.9%, 27/41). All K1 and K2 HMKP and non-HMKP isolates were positive forrmpA.Aerobactinwas found among 95.0 and 97.5% of K1 and K2 isolates. ST23 was found to be the most prevalent ST among 69 HMKP isolates with K1, K2, K5, K20, and K57 (27.5%, 19/69) and was only found among K1 isolates. ST65 was the second most prevalent ST (26.1%, 18/69) and was also only found among K2 isolates. ST23-K1 HMKP isolates (84.2%, 16/19) were associated with PLA, while ST65-K2 isolates were correlated with more types of infections relative to ST23-K1 isolates. PFGE results showed that the homology of 84 HMKP isolates was diverse. Only five PFGE clusters with more than 75% similarity accounted for more than three isolates. These five PFGE clusters only accounted for 35 (41.7%, 35/84) isolates. In conclusion, our study first found that hypertension and male patients with 41-50 years old were independent risk factors. The composition of ST types and PFGE clusters amongK. pneumoniaeK2 isolates was more diverse than K1 isolates. K1 and K2 HMKP isolates had respective specific profiles of virulence-associated genes.
authors.affiliation: Department of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Yinjuan
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Department of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhan
authors.affiliation: Department of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Department of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Duan
authors.affiliation: Department of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Zhihao
authors.initials: Z
authors.lastname: Hao
authors.affiliation: Department of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Jingnan
authors.initials: J
authors.lastname: Lv
authors.affiliation: Department of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Xiuqin
authors.initials: X
authors.lastname: Qi
authors.affiliation: Public Health Research Institute Tuberculosis Center, New Jersey Medical School, Rutgers University Newark, NJ, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.affiliation: Public Health Research Institute Tuberculosis Center, New Jersey Medical School, Rutgers University Newark, NJ, USA.
authors.forename: Barry N
authors.initials: BN
authors.lastname: Kreiswirth
authors.affiliation: Department of Respiratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Liangxing
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University Wenzhou, China.
authors.forename: Fangyou
authors.initials: F
authors.lastname: Yu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002681:China / Q000453:epidemiology; D015897:Comorbidity; D005260:Female; D006801:Humans; D007710:Klebsiella Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D010641:Phenotype; D010802:Phylogeny; D015995:Prevalence; D012307:Risk Factors; D065288:Serogroup; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D037521:Virulence Factors
keywords: Klesiella pneumonia; characteristics; epidemiology; hypermucoviscosity