Jpn. J. Infect. Dis., 53, 2000

Laboratory and Epidemiology Commumications

Comparision of Genomic DNA Fingerprlntlng Using Pulsed‑Field
Gel Electrophoresis and Antibiotic Susceptibility of Clinical lsolatesof Methicillin‑Resistant Staphylococcus aureus
between Chiang Mai and Tbkyo
Prasit Tharavichitkull , Fumiko Kirikae2, Aki Kaneko2, Masahito Hashimoto2,
Kiminori Toyooka2, MitsuharuHasegawa2, Kuniko Iwata2, Tadatoshi Kuratsuji2,
Yoshio Yazaki2, Thira Sirisanthana3 and Teruo Kirikae2*JDepartment of Microbiology and 3Deparment of Medicine, Faculo, of Medicine, Chiang Mai UniversiOr,Chiang Mai 50200, Tlhailand and2International Medical Center ofJapan,
Toyama ll2111, Shinjuku, To砂0 162‑8655

Communicated by Hiroshi Yoshikura(Accepted May 26, 2000)

major nosocomial pathogen in both Thailand and Japan ( 1 ‑3)･

Bio‑Rad Laboratories, Hercules, Calif., USA), antibioticresistance (WalkAwayTM, Dade Behring, Deerfield, Ill., USA),

Genomic DNA fingerpnntlng uSlng Pulsed‑field gel electro‑

enterotoxin serotype (SET‑RPLA: Denka Seiken Cot, Tokyo),

Methicillin‑resistant Staphylococcus aureus (MRSA) is aphoresis (PFGE) is a powerful tool to investigate the source,

toxic shock syndrome toxin‑I (TSST‑1) production (TST‑transmission, and spread of MRSA infection (4).
Nine and sixteen MRSA isolates obtained respectively from

RPLA: Denka Seiken), and coagulase serotype (Denka

patients in a universlty hospital in Chiang Mai, Thailand

Isolates &om Chiang Maishowed 5 different PFGE patterns
and 7 different antibiotic pattems (Fig. 1 and Table 1). Band‑

Seiken).

(January to February 2000) and from patients in a hospital

based clusteranalysis of PFGE pattems (MolecularAnalystTM :(with about 900 beds) in Tokyo (February 1999 to February

BioIRad) revealed a more than 94% simiIarityamongthe five2000) were analyzed for chromosomal DNAtype (Contour‑clamped homogeneous electriCfield system; CHEF MapperTM:isolates (Fig. 2). Chiang Mai isolates with PFGE pattem A,

Table I. Antibiotic pattem classifled by MIC pattem of I 6antibiotics agalnSt MRSA
Antibiotic Antibiotics listed MIC (LLg/ml) of:patteminfootnote#EM

GM【■."■nuMINO

VCM

CLDMSTF0M

氏RRRR良R良氏臥氏II氏

RSR氏R氏SSSSSSSSSSSSSSSsR氏IssIssRssR氏

SSSSSSSRRRR氏R良R

R氏氏R氏R氏氏

RS良臥S臥SRS S I l I S T▲ S

SSSSSSSSsRR氏R氏礼氏

SSSSSSSSS氏RI氏RIS

等芸芸Tg

TJ

J‑

巾JbICIdIeIf1gI

PCG: benzyl‑penicillin, MPIPC: oxacillin, ABPC: ampicillin, PIPC:piperacillin, CEZ: cefazolin,

CMZ: cchetazole, CTM: cefotiam, IPM: imlPenem/cilastatin, EM: erythromycin, GM: gentamlCln,
OFLX: onoxacirL, MINO: minocycline, VCM: vancomysin, CLDM: clindamycin, ST: streptomycln,FOM: fosfomycin, R: resistant, S: susceptible, I:intermediate
Antibiotic pattem Ta is the same as pattem Ja.

#pCG, MPIPC, ABPC, PIPC, CEZ, CMZ, CTM, IPM, OFLX

*Corresponding author: Fax: +8 1 ‑3‑3202‑7364, E‑mail: tkirikae@ri. imcj. go.jp
86Jpn. J. Infect. Dis., 53, 2000
M 1 234567891011M

Table 2. Phenotypic and genotypic characterization of the S. au榔isolates

PFGE Antibiotic Enterotoxin
pattempatternATb,TcB

TrCTg+ rIlIA

一一一一一BrIIIITSST‑I CoagulaseC

DI‑一 l 一type

ⅣⅣⅣⅣⅣ

D Ta,Td, TeEFGHI∫KLMN0pqRsTU

TelCーe ∫ ∫ la Jh le le lC IC le lC IC lg ld Jd lb

L 一一 l 一 J 一一一一 l 一一一一一一 + 一一一一 l l 一 l 一一 l 一一 r

一+ + + + +十十+ 十十一 L I L E 一一一 l l l 一一一一一

ⅡⅡⅡⅡⅡⅡⅡⅡ

Fig. I. Pulsed‑field electrophoresis of SmaI‑digested genomic DNA&om MRSA isolates.

Lanes l19: MRSA isolatesfrom Chiang Mai, pattemsA, A, D, E, D,B, C, D, and D, respectively. Lanes 10 and ll: two Tokyo isolateswith pattems 0 and T

9095100%

ABCDEFGHI KLMNOpQRSTU

Mai and Tokyo isolates except for pattem Ta (Ja). MRSAs
isolatedinThailand and those isolatedinJapanwerethus quite
different in terms of their biological and genomic properties.

REFERENCES
1. Siriszmdlana, T., Thamvichitkul, P.and Baosoung, V. (1987):
Tolerance to cephalothin in strains of Staphylococcus

auTleuS isolated from blood cultures. J. Med. Assoc. Thai.
70, 228‑233.

2. Kaneko, A., Miyazawa, H., Kirikae, F., Toyooka, K.,
Hashimoto, M., Yamasaki, S., Hasegawa, M., Takeuchi,C., Kuratsuji, T., Sumlya, M., Kobori, 0., Yazaki, Y. andKirikae, T. (2000): Epidemiological analysis ofmethicillin‑resistant Staphylococcus aureus outbreaks ina neonatal intensive care unit by genomic DNA finger‑printing using Pulsed‑rleld gel electrophoresis. Jpn. J.

Fig. 2. Cluster analysis or MRSA isolates based on PFGE pattems.

Infect. Dis. 53, 82184.

3. Kaneko, A., Kimura, S., Kirikae, F., Toyooka, K.,
Hashimoto, M., Hasegawa, M., Mezaki, M., Kuratsuji, T.,
Sumiya, M., Kobori, 0., Yazaki, Y. and Kirikae, T. (2000):

but not those with other PFGE patterns, produced enterotoxin

EpidemiologlCal analysts Of a methicillin‑resistant(Table 2). The produced enterotoxin was type A. All theisolates produced coagulase type IV, but not TSST‑ I.
All the 16 isolates from Tokyo showed different PFGE

Staphylococcus aureus outbreak in a surgery ward bypatterns, yet the similaritywas more than94%. Eight different

genomic DNA fingerprinting uslng Pulsed‑field gelelectrophoresis. Jpn. J. Infect. Dis. 53, 84‑85.

antibiotic pattems were revealed (Fig. 2 and Table 1). Most

4. Ichiyama, S., Ohta, M., Shimokata, K., Kato, N. andTokyo isolates produced enterotoxintype C, coagulasetype

Takeuchi, J. (199 1): Genomic DNA flngerPrintings by

II, and TSSTl 1. The clusteranalysis ofPFGE pattem revealed
that similarity w仙in individual hospitals was high whilepulsed‑field gel electrophoresis as an epidemiologlCal
marker for study of nosocomial infections caused bysimilaritybetween Chiang Mai and Tokyo isolates was low

methicillin‑resistant Staphylococcus aureus. J. Clin.

(Fig. 2). Antibiotic pattems were different between Chiang

Microbio1., 29, 2690‑2695.

87