Bacterial diversity in surgical site infections: not just aerobic cocci any more.
OBJECTIVE
To evaluate the microbial diversity in chronic surgical site infections (SSIs).


METHODS
Bacterial populations in 23 chronic SSIs were identified using bacterial tag-encoded FLX amplicon pyrosequencing (bTEFAP),which is an universal bacterial identification method.These results were then validated using quantitative polymerase chain reaction (qPCR).


RESULTS
bTEFAP identified two previously uncharacterised Bacteroidales in all of the SSIs and showed that it was the predominant population in the majority of these chronic wounds. Other bacteria identified included Corynebacterium spp., Peptoniphilus spp., Staphylococcus spp., Staphylococcus aureus, Serratia marcescens, Prevotella spp. and Pseudomonas aeruginosa. Rarefaction analysis of the data indicated that, on average, six genera occurred in any given SSI, suggesting that such infections are multispecies. On average, over 60% of the bacteria evaluated in the SSIs were anaerobic bacilli. The previous literature indicates that aerobic cocci predominate in such wounds.


CONCLUSIONS
This modern molecular survey indicates that our previous understanding of which bacteria cause SSIs may be faulty. The high prevalence of anaerobic bacilli and the overwhelming predominance of two previously uncharacterised Bacteroidales suggest that such bacteria may be a leading contributor to such infections. Further research on the identification and treatment of such bacteria are warranted.
Southwest Regional Wound Care Centre, Lubbock,Texas, USA.
R D
RD
Wolcott
V
V
Gontcharova
Y
Y
Sun
A
A
Zischakau
S E
SE
Dowd
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001424:Bacterial Infections / Q000453:epidemiology / Q000382:microbiology*; D015373:Bacterial Typing Techniques; D001439:Bacteroides / Q000235:genetics; D018441:Biofilms / Q000254:growth & development; D002908:Chronic Disease; D016000:Cluster Analysis; D003352:Corynebacterium / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D015999:Multivariate Analysis; D016133:Polymerase Chain Reaction; D015995:Prevalence; D011549:Pseudomonas / Q000235:genetics; D016324:Sequence Tagged Sites; D013210:Staphylococcus / Q000235:genetics; D013530:Surgical Wound Infection / Q000453:epidemiology / Q000382:microbiology*; D013781:Texas / Q000453:epidemiology
D004269:DNA, Bacterial