title: In vitro and in vivo activity of first generation cephalosporins against Leptospira.
abstract: Third generation cephalosporins are commonly used in the treatment of leptospirosis. The efficacy of first generation cephalosporins has been less well-studied. Susceptibility testing of 13 Leptospira strains (11 serovars) to cefazolin and cephalexin was conducted using broth microdilution. Median minimal inhibitory concentration (MIC) for cefazolin and cephalexin ranged from < 0.016 to 2 μg/mL (MIC(90) = 0.5 μg/mL) and from 1 to 8 μg/mL (MIC(90) = 8 μg/mL), respectively. Efficacy of cefazolin and cephalexin in an acute lethal hamster model of leptospirosis was studied. Survival rates for cefazolin were 80%, 100%, and 100%, and survival rates for cephalexin were 50%, 80%, and 100% (treated with 5, 25, and 50 mg/kg per day for 5 days, respectively). Each treatment group showed improved survival compared with no treatment (P < 0.01), and none of the therapies, regardless of dose, was statistically significantly different than doxycycline. These results support a potential role for first generation cephalosporins as alternative therapies for leptospirosis.
authors: Department of Medicine, Wilford Hall Medical Center, Lackland Air Force Base, Texas, USA. brande.harris.1@us.af.mil
authors: Brande M
authors: BM
authors: Harris
authors: Peter J
authors: PJ
authors: Blatz
authors: Mary K
authors: MK
authors: Hinkle
authors: Suzanne
authors: S
authors: McCall
authors: Miriam L
authors: ML
authors: Beckius
authors: Katrin
authors: K
authors: Mende
authors: Janelle L
authors: JL
authors: Robertson
authors: Matthew E
authors: ME
authors: Griffith
authors: Clinton K
authors: CK
authors: Murray
authors: Duane R
authors: DR
authors: Hospenthal
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002511:Cephalosporins / Q000494:pharmacology*; D006224:Cricetinae; D004318:Doxycycline / Q000627:therapeutic use; D024881:Drug Resistance, Bacterial; D005260:Female; D007919:Leptospira / Q000187:drug effects*; D007922:Leptospirosis / Q000188:drug therapy*; D008647:Mesocricetus; D008826:Microbial Sensitivity Tests
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D004318:Doxycycline