Jpn. J. Infect. Dis., 55, 2002

Laboratory and Epidemiology Communications

Reproducibility of Oral Bacterial lsolation in the Elderly
Hidenobu Senpuku*, Akio Tadal, Masanari Takada2,Tsutomu Sato2 and Nobuhiro Hanada3

Department ofBacterioloBy, National Institute ofInfectious Diseases, and3Department of Oral Health, National Institute of Public Health,
7Toyama 1‑23‑1, Shinjuku‑ku, 7Tolg)0 1 62‑8640,

JChiba Cio; Health Center:

Saiwai 1‑3‑9, Mihama‑ku, Chiba 261‑8755 and2Department of Preventive and CommunityDentist77), Nl'ppon Dental UniversiO?,Fujimi 1‑9‑20, Chiyoda‑ku, ToIvo 1 02‑8159

Communicated by Hamo Watanabe(Accepted June 7, 2002)

Aspiration pneumonia is a major Cause Of death among

enrolled in the present study which was conducted in Julyelderly persons (1) because dysphagia and decreased c?ughand August, 2001.

renex are oRen associatedwith aging. Oral bacterial Dora lS anSamples were taken舟om dental plaque on the upper molar

important factor of the occurrence of aspiration pneumonia

teeth or upper molar portions of dentures. The plaque samples(2). Oral bacterial flora is composed of both aerobic andwere placed in transport nuid (0.4% agar, 0. 1 5%thioglycollate/anaerobic bacteria species due to the complex structure of thephosphate buffered saline) and sent to Bio Medical Labora‑oral cavity. Data regarding pathogenic aerobic bacteria in the

tory (Tokyo) for?nalysis･ For the detection and identification

oral cavityofthe elderly (3) and the association ofperiodontalof aerobic bactena species, each sample was poured directly

disease‑causing anaerobic bacteria with pneumonia (4) haveonto chocolate agar, OPA staphylococcus, and Drigalski agar

been reported. This report fわcuses on the detection rates oforal anaerobic bacteria measured at two different times inplates (Nippon Becton Dickinson Co., Ltd., Tokyo) using astick. The plates were incubated in an atmosphere of5% CO2

elderly subjects.

in H2 gas at 37oC f♭r 24‑48 h. Representative microbial

Thirty‑three elderly people (73,4士5.6 year‑old in average),colonies &om each plate were examined for appearance, gram

12 males and 21 females, from Saitama Prefecture werestain, bemolytlC, CatalytlC, and oxidase reaction characters

Table 1 ･ Detection rate ofmicrobial pathogens in dental plaque舟om the elderly( 1 ) aerobic microorganisms

No. positives No. positives at 2md exam
at lst exam (% total)(I)among positives at lst exam II/I (%)(ⅠⅠ)

Candida sp.

14 (42.4)

HaemophiluS Parainjluenzae

13 (39.4)

4/13 (30.8)

A cinetobacler calcoaceticus

74422011

7/14 (50.0)

10 (30.3)

4/10 (40,0)Coワ,nebacterium sp.

7 (21.2)

2/7 (28.6)

B(7(.i/ILLS SP.

6 (18.2)

2/6 (33.3)

Enlerobacte7･ Cloacae

4(12.1)0/4 (0)

Coagulase (‑) Staphylococcus

4(12.1)

1/4 (25.0)

Klebsiella pneumoniae

4(12.1)

1/4 (25.0)(2) anaerobic bacteria species

No. positives No. positives at 2md exam
at lst exam (% total)(Ⅰ)

among positives at lst exam II/I (%)(H)

Capnocytophaga sp.

23 (69.7)

Prevotella melam'nogen ica

22 (66.7)

Prevotella oriS

10 (30.3)

9/10 (90.0)

Fusobacterium mLCleattLm

10 (30.3)

9/10 (90.0)

231 2997330

23/23 (100)12/22 (54.5)

PrevoteIla inlen77edia

7 (21.2)

7/7 (100)

Fusobacterium necrophonLm

5 (15.2)

3/5 (60.0)

Prevolella denticola

3(9,1)

3/3 (100)

FusobacteritLm SP.

3(9,1)

0/3 (0)*Co汀eSpOmding author: Tel: +81‑3‑5285‑1 1 1 1, Fax: +81‑3‑5285‑

1 1 72, E‑mail: hsenpuku@nih,goJp

61

Jpn. J. Infect. Dis., 55, 2002
retained anaerobic species (except Fusobacterium sp･) detected(5). The bacteria identified were methicillin‑sensitive (MSSA)
and ‑resistant Staphylococcus aureus (MRSA), (detected byPS latex, rabbit plasma, and MRSA screening plates [Nipponin the first examination, Anaerobes appeared more stable in
the elderly persons'oral norathan did aerobes probably because

Becton Dickinson]), Pseudomonas sp. (detected by VITEKof the bio別m in the oral cavlty Which provides anaerobeswith an optimal environment.

lBioMerieux Vitek Japan, Tokyo]), Haemophilus injluenzae(H. injluenzae) (detected by a Haemophilus ID4 plate (Nippon
Becton Dickinson), and Candida sp. (detected by Candida

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62