TY - JOUR
T1 - Comparison of prevalence of virulence factors for Klebsiella pneumoniae liver abscesses between isolates with capsular K1/K2 and non-K1/K2 serotypes
AU - Yu, Wen Liang
AU - Ko, Wen Chien
AU - Cheng, Kuo-Chen
AU - Lee, Ching Chien
AU - Lai, Chien-Cheng
AU - Chuang, Yin Ching
N1 - Funding Information:
This work was supported by a research grant (95CM-TMU-10) from Taipei Medical University, Taipei, and Chi-Mei Medical Center, Tainan, Taiwan. The authors thank Chang-Phone Fung (Section of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan) for assistance with capsular serotyping and Chin-Li Lu (Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan) for assistance with statistical analysis.
PY - 2008/9
Y1 - 2008/9
N2 - Hypermucoviscosity, rmpA (regulator of mucoid phenotype), aerobactin (an iron siderophore), kfu (an iron uptake system), allS (associated with allantoin metabolism), and K1/K2 capsules are important virulence determinants in Klebsiella pneumoniae for liver abscesses. We determined the prevalence of these virulence factors of 50 nonrepeat K. pneumoniae isolates recovered from patients with primary liver abscesses who were treated at 2 medical centers in Taiwan. Virulence genes were surveyed by polymerase chain reaction analysis. The prevalence of hypermucoviscosity phenotype, plasmid-born rmpA, aerobactin, kfu, and allS genes revealed 96%, 100%, 100%, 100%, and 100% in 26 capsular K1 isolates; 90%, 100%, 100%, 0%, and 0% in 10 K2 isolates; and 79%, 86%, 93%, 50%, and 0% in 14 non-K1/K2 isolates; respectively. When injected into mice intraperitoneally, regardless of any capsule K serotype, K. pneumoniae isolates with hypermucoviscosity phenotype as well as presence of rmpA and aerobactin genes exhibited high virulence for mouse lethality (LD50, 2 CFU). Without significant difference in the prevalence of expressing hypermucoviscosity phenotype and carriage of rmpA and aerobactin genes, these virulent non-K1/K2 isolates are as capable as K1/K2 isolates of causing primary liver abscesses.
AB - Hypermucoviscosity, rmpA (regulator of mucoid phenotype), aerobactin (an iron siderophore), kfu (an iron uptake system), allS (associated with allantoin metabolism), and K1/K2 capsules are important virulence determinants in Klebsiella pneumoniae for liver abscesses. We determined the prevalence of these virulence factors of 50 nonrepeat K. pneumoniae isolates recovered from patients with primary liver abscesses who were treated at 2 medical centers in Taiwan. Virulence genes were surveyed by polymerase chain reaction analysis. The prevalence of hypermucoviscosity phenotype, plasmid-born rmpA, aerobactin, kfu, and allS genes revealed 96%, 100%, 100%, 100%, and 100% in 26 capsular K1 isolates; 90%, 100%, 100%, 0%, and 0% in 10 K2 isolates; and 79%, 86%, 93%, 50%, and 0% in 14 non-K1/K2 isolates; respectively. When injected into mice intraperitoneally, regardless of any capsule K serotype, K. pneumoniae isolates with hypermucoviscosity phenotype as well as presence of rmpA and aerobactin genes exhibited high virulence for mouse lethality (LD50, 2 CFU). Without significant difference in the prevalence of expressing hypermucoviscosity phenotype and carriage of rmpA and aerobactin genes, these virulent non-K1/K2 isolates are as capable as K1/K2 isolates of causing primary liver abscesses.
KW - Hypermucoviscosity
KW - Klebsiella pneumoniae
KW - Liver abscess
KW - Virulence
KW - rmpA gene
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U2 - 10.1016/j.diagmicrobio.2008.04.007
DO - 10.1016/j.diagmicrobio.2008.04.007
M3 - Article
C2 - 18486404
AN - SCOPUS:49549090466
SN - 0732-8893
VL - 62
SP - 1
EP - 6
JO - Diagnostic Microbiology and Infectious Disease
JF - Diagnostic Microbiology and Infectious Disease
IS - 1
ER -
