Jpn. J. Infect. Dis., 54, 2001

Laboratory and Epidemiology Communications

Epidemiological Survey of B‑Hemolytic Streptococci Isolated fromAcute Pharyngitis in a Private Pediatric PracticeTadahiro KarasawaI･ 2, Kentaro Takahashi2 and Shinichi NakamuraI *JDepartment of Bacteriology, Graduate School ofMedical Science, Kanazawa Un iversiO!.
Takara‑machi 13‑I. Kanazawa 920‑8640 and2Takahashi Pediatric Clin ic,

Hikos0‑machi I‑13‑28, Kanazawa 920‑0901
Communicated by Hiroshi Ybshikura(Accepted April 20, 200 I)

PharyngltlS is one of the most common illnesses seen in<50% oftotal colonies; 2+, 5 1‑200 BHS‑like colonies, <50%

the pnmary medical care of children. Most cases are of viraloftotal colonies; 3+, >200 BHS‑like colonies, <50% oftotalcolonies; 4+, >200 BHS‑like colonies, and 50‑100% of total

etiology, while others are mainly bacterial (I,2). The mostcolonies. Lancefield's grouplng and T serotyplng Wereprevalent bacterial pharyngitis is due to 8‑hemolytic strepto‑cocci (BHS), which are. responsible for suppurative andmissible. However, microbiologic data regarding streptococcal

perform;d using a latex agglutination kit (STREPT LASEIKEN; Denka Seiken Co., Ltd., Tokyo) and by group AT typ.ing sera (Denka Seiken)･ respectively. At least fivepharyngltlS in Japanese pediatric practices have been limitedcolonleS On the initial culture were examined for Lancefield's(3). The present study aimed at elucidating the microbiologic
status of streptococcal pharyngitis in pediatric outpatients.

grouplng and T serotyplng.

nonsuppurative complicat10nS and are potentially highly trans‑Patients were 2 months to 19 years of age. Of360 specimens

This study was conducted at a private outpatient practice

examined, 96 (26.7%) were BUS‑positive. Among them, 77

located in a metropolitan area of Kanazawa, Japan, between
November 1 996and July 1 998. Children withclimical diagnosis

samples were 4+, 1 1 samples 3+, 4 samples 2+, and 4 samplesof acute pharyngltlS Were enrolled. Patients who had beenyears, consistent with the observations of previous reports

treated with antibiotics in the previous 3 days or those who(4,5). The isolates were homogeneous for Lancefield's grouprefused swab sampling were excluded. A throat specimen &om

and T antigen･ Although groPp A was predominant (90each patient was collectedusing a cotton swab and immediately

isolates, 93･8%), groYps B (two Iso一ates, 2･ 1%), C (One isolate,spread over a 15% sheep blood agar. The agar plates were1.0%), and G (three lSOlates, 3. 1%) were also detected (Table1+. Age distribution of the BHS‑positive patients was 1‑14

incubated at 370C under an aerobic condition. Growth ofliHS1 ). Streptococcal pharyngitis was kequent during Novemberin the initial culture plate was categorized as fわllows: 1+,

to December 1997, when the most frequent isolate was T‑
untypable group A. There was a change in BHS serotypes

1 150 BHS‑like colony(S) (i.e., the colony exhibited B‑hemolysis,
the appearance of which was consistent with that ofBHS),

during late surrmer to autumn in 1997. T serotypes of isolates
were relatively diverse before the summer, while in the*Corresponding author: Tel: +8 1 ‑76‑265‑2200, Fax: +8 I ‑76‑234‑

autumn and later, T 1, T 2, and T 6 serotypes came to be

4230, E‑mail: nakamura@med.kanazawa‑U.acjp

isolated consistently. It is customary in Japan that families

76Jpn. J. Infect. Dis., 54, 2001
Table 1. Isolation of B‑hcmolytic streptococci
1996

1997

1998

Nov Dec Jam Fcb Mar Apr May Jun Jut Aug Sep Oct Nov Dec Jam Feb Mar Apr May Jun Jut Total
Lanceficld 's Tgroup

scrotypeA

1

12222/28 114121111211131112 0ノ 0 4 4 1 1 ‑1 2 3 2 1 つJ2ll11161121311 4/49

25
28

24

1383264

21UT2111

DU C G
1TotaINo.ofisolatesll

oNo･ofpaticntstestcd

0O

537104141821830

6230

17212314

1461121

25

1426

523

319. Agglutination was obserbed against both T‑2 and T‑28 antisera･
2UT, untypable.
3Each isolate was derived舟om a single β‑hcmolytic streptococcus‑positive paticnt･

With preschool‑ 0r elementary school‑aged chil血en spend aREFERENCES

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