Method of detecting β-lactam antibiotic induced vancomycin resistant MRSA (BIVR)

Journal of Infection and Chemotherapy

et al. 2006

Section: Identification Of Bivr Among Mrsasmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Nosocomial infection of β-lactam antibiotic-induced vancomycin-resistant Staphylococcus aureus (BIVR)

Hososaka

Journal of Infection and Chemotherapy

et al. 2006

“…BIVR and non-BIVR MRSA strains were isolated from clinical materials according to a method described elsewhere previously using Mu3 agar (Nippon Becton-Dickinson, Tokyo, Japan) (13). Among these, a representative BIVR strain, K744, showed stable VAN resistance in the presence of 1 g/ml of ceftizoxime (ZOX).…”

Section: Methodsmentioning

confidence: 99%

“…However, the combination therapy of VAN and a ␤-lactam antibiotic caused the emergence of VAN-resistant MRSA (15,26), designated ␤-lactaminduced VAN-resistant MRSA (BIVR) (12,14). Currently, about 20% of MRSA strains isolated from septicemia patients have been reported to be BIVR (13). A stereochemical specificity of ␤-lactam antibiotics for the BIVR induction was not found, as 46 species of ␤-lactam antibiotics have been tested so far (13).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Rapid Depletion of Free Vancomycin in Medium in the Presence of β-Lactam Antibiotics and Growth Restoration in Staphylococcus aureus Strains with β-Lactam-Induced Vancomycin Resistance

Antimicrob Agents Chemother

Matsui

et al. 2009

Growth of the BIVR cells to an absorption level of ϳ0.3 at 578 nm required about 24 h in the presence of vancomycin alone at the MIC (4.0 g/ml). However, growth was achieved in only about 10 h when 1/1,000 to 1/2,000 the MIC of ␤-lactam antibiotic was added 2 h prior to the addition of vancomycin, suggesting that the ␤-lactams shortened the time to recovery from vancomycin-mediated growth inhibition. Free vancomycin in the culture medium decreased to 2.3 g/ml in the first 8 h in the culture containing vancomycin alone, yet cell growth was undetectable. When the vancomycin concentration dropped below ϳ1.5 g/ml at 24 h, the cells began to grow. In the culture supplemented with the ␤-lactam 2 h prior to the addition of vancomycin, the drug concentration continuously dropped from 4 to 0.5 g/ml in the first 8 h, and the cells began to grow at a vancomycin concentration of ϳ1.7 g/ml or at 4 h of incubation. The gene encoding the enzyme involved in D-Ala-D-lactate synthesis was undetectable. Based on these results, we concluded that BIVR is attributable mainly to a rapid depletion of vancomycin in the medium triggered or promoted by ␤-lactam antibiotics.

show abstract

Investigation of β-lactam antibiotic-induced vancomycin-resistant MRSA (BIVR)

Yamaguchi

Journal of Infection and Chemotherapy

et al. 2005