Ciprofloxacin-resistant Salmonella enterica Typhimurium and Choleraesuis from pigs to humans, Taiwan.
We evaluated the disk susceptibility data of 671 nontyphoid Salmonella isolates collected from different parts of Taiwan from March 2001 to August 2001 and 1,261 nontyphoid Salmonella isolates from the National Taiwan University Hospital from 1996 to 2001. Overall, ciprofloxacin resistance was found in 2.7% (18/671) of all nontyphoid Salmonella isolates, in 1.4% (5/347) of Salmonella enterica serotype Typhimurium and in 7.5% (8/107) in S. enterica serotype Choleraesuis nationwide. MICs of six newer fluoroquinolones were determined for the following isolates: 37 isolates of ciprofloxacin-resistant (human) S. Typhimurium (N = 26) and Choleraesuis (N = 11), 10 isolates of ciprofloxacin-susceptible (MIC <1 mg/mL) (human) isolates of these two serotypes, and 15 swine isolates from S. Choleraesuis (N = 13) and Typhmurium (N = 2) with reduced susceptibility to ciprofloxacin (MIC >0.12 microg/mL). Sequence analysis of the gryA, gyrB, parC, parE, and acrR genes, ciprofloxacin accumulation, and genotypes generated by pulsed-field gel electrophoresis with three restriction enzymes (SpeI, XbaI, and BlnI) were performed. All 26 S. Typhimurium isolates from humans and pigs belonged to genotype I. For S. Choleraesuis isolates, 91% (10/11) of human isolates and 54% (7/13) of swine isolates belonged to genotype B. These two genotypes isolates from humans all exhibited a high-level of resistance to ciprofloxacin (MIC 16-64 mg/mL). They had two-base substitutions in the gyrA gene at codons 83 (Ser83Phe) and 87 (Asp87Gly or Asp87Asn) and in the parC gene at codon 80 (Ser80Arg, Ser80Ile, or Ser84Lys). Our investigation documented that not only did these two S. enterica isolates have a high prevalence of ciprofloxacin resistance nationwide but also that some closely related ciprofloxacin-resistant strains are disseminated from pigs to humans.
Hsueh
Po-Ren
PR
Department of Laboratory Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan. hsporen@ha.mc.ntu.edu.tw
Teng
Lee-Jene
LJ
Tseng
Sung-Pin
SP
Chang
Chao-Fu
CF
Wan
Jen-Hsien
JH
Yan
Jing-Jou
JJ
Lee
Chun-Ming
CM
Chuang
Yin-Ching
YC
Huang
Wen-Kuei
WK
Yang
Dine
D
Shyr
Jainn-Ming
JM
Yu
Kwok-Woon
KW
Wang
Li-Shin
LS
Lu
Jang-Jih
JJ
Ko
Wen-Chien
WC
Wu
Jiunn-Jong
JJ
Chang
Feng-Yee
FY
Yang
Yi-Chueh
YC
Lau
Yeu-Jun
YJ
Liu
Yung-Ching
YC
Liu
Cheng-Yi
CY
Ho
Shen-Wu
SW
Luh
Kwen-Tay
KT
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D002939:Ciprofloxacin / Q000494:pharmacology*; D004351:Drug Resistance / Q000235:genetics*; D006801:Humans; D007223:Infant; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D015995:Prevalence; D012480:Salmonella Infections / Q000188:drug therapy / Q000453:epidemiology*; D012481:Salmonella Infections, Animal / Q000188:drug therapy / Q000453:epidemiology*; D012476:Salmonella arizonae / Q000187:drug effects* / Q000302:isolation & purification; D019779:Salmonella enterica / Q000187:drug effects* / Q000302:isolation & purification; D013552:Swine; D013624:Taiwan / Q000453:epidemiology
D000890:Anti-Infective Agents; D002939:Ciprofloxacin