Anaerobic culture of diabetic foot infections: organisms and antimicrobial susceptibilities.
BACKGROUND
The prevalence of diabetes mellitus is high in Singapore. Infections of the lower limb are significant causes of morbidity in this population. Although the aerobic bacteriology of these infections is well-documented, there is less data available on the anaerobic pathogens involved. This study sets out to describe the anaerobic bacteria associated with diabetic foot infections, and evaluates the susceptibility to 3 antimicrobials with anaerobic activity.


METHODS
Anaerobic culture was performed on operative samples taken from diabetic foot infections. Organisms were identified through standard microbiological methods and commercial identification kits. Antimicrobial susceptibility testing to clindamycin, metronidazole and imipenem was performed by agar dilution.


RESULTS
One hundred and two strains of strict anaerobic bacteria were isolated from 30 unique specimens. The predominant anaerobic isolates were Peptostreptococcus spp. (46%) and Bacteroides fragilis group (19%). Antibiotic resistance was detected for clindamycin (18%), metronidazole (1%) and imipenem (2%).


CONCLUSIONS
Multiple anaerobic species can be isolated from diabetic foot infections. A significant proportion of isolates are resistant to clindamycin, while resistance to imipenem and metronidazole remains low.
Ng
Lily S Y
LS
Division of Laboratory, Changi General Hospital, Singapore.
Kwang
Lee Ling
LL
Yeow
Susan C S
SC
Tan
Thean Yen
TY
D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001420:Bacteria, Aerobic / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D004269:DNA, Bacterial / Q000032:analysis; D017719:Diabetic Foot / Q000601:surgery*; D024901:Drug Resistance, Multiple, Bacterial; D004359:Drug Therapy, Combination; D006801:Humans; D021141:Nucleic Acid Amplification Techniques; D012189:Retrospective Studies; D013530:Surgical Wound Infection / Q000188:drug therapy / Q000382:microbiology*
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial