Tissue and serum levofloxacin concentrations in diabetic foot infection patients.
OBJECTIVE
Levofloxacin has a high bioavailability and a broad antibacterial spectrum which covers the common pathogens found in acute and chronic diabetic foot infections. The purpose of our study was to determine the serum and tissue concentrations of levofloxacin when administered orally in patients with infected diabetic foot ulcers and to compare these values with microbiological findings.


METHODS
Ten outpatients with diabetes and ulcerations of the lower extremity were included. All patients received oral levofloxacin therapy at a dose of 500 mg once daily. Wound tissue and serum samples were collected and levofloxacin concentrations determined by HPLC with fluorescence detection. Additionally, microbiological cultures were performed from swabs and debrided wound tissue, both before and after treatment. MICs of levofloxacin for all bacterial isolates were determined using the Etest.


RESULTS
Following oral treatment with levofloxacin for an average of 10 +/- 3.8 days, all patients received debridement at the affected limbs. The levofloxacin concentrations in necrotic wound tissue were between 2.33-23.23 mg/kg and between 0.12-6.41 mg/L in serum. Tissue-to-serum ratios of levofloxacin concentrations for each patient were >1.0. The MIC values for all 17 initially isolated bacteria were < or = 2 mg/L. In half of our patients, fluoroquinolones were one of the few oral monotherapy options where the spectrum covered all initially isolated pathogens.


CONCLUSIONS
Our data showed good tissue penetration of levofloxacin in diabetic foot ulcers. In combination with adequate surgical debridement, levofloxacin seems well suited to the treatment of skin structure infections of diabetics caused by susceptible organisms.
Oberdorfer
K
K
Institute of Hygiene, University of Heidelberg, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany. Klaus_Oberdorfer@med.uni-heidelberg.de
Swoboda
S
S
Hamann
A
A
Baertsch
U
U
Kusterer
K
K
Born
B
B
Hoppe-Tichy
T
T
Geiss
H K
HK
von Baum
H
H
D000284:Administration, Oral; D000900:Anti-Bacterial Agents / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D001424:Bacterial Infections / Q000188:drug therapy* / Q000378:metabolism / Q000382:microbiology; D002851:Chromatography, High Pressure Liquid; D017719:Diabetic Foot / Q000188:drug therapy* / Q000378:metabolism / Q000382:microbiology; D006801:Humans; D064704:Levofloxacin; D008826:Microbial Sensitivity Tests; D015242:Ofloxacin / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D014018:Tissue Distribution
D000900:Anti-Bacterial Agents; D064704:Levofloxacin; D015242:Ofloxacin