Efficacy Of Cefazolin Research Articles

Efficacy of Cefazolin in the Treatment of Pregnancy and Vaginal GBS Infection and Its Influence on Inflammation and Maternal and Infant Outcomes

Efficacy of Cefazolin in the Treatment of Pregnancy and Vaginal GBS Infection and Its Influence on Inflammation and Maternal and Infant Outcomes

Triazolylthioacetamides Confer Inhibitory Efficacy against Metallo-β- Lactamase IMP-1

Background: : The appearance of antibiotic resistance caused by metallo-β-lactamases (MβLs) is a global public health threat. Developing MβLs inhibitor is an effective way to overcome antibiotic resistance. Recently, azolylthioacetamides were reported to be promising MβLs inhibitors. Methods:: Triazolylthioacetamides were synthesized and tested for inhibition activity against the purified MβL IMP-1. Antimicrobial activities of these inhibitors in combination with cefazolin were evaluated. Isothermal Titration Calorimetry (ITC) was employed to characterize the binding of the inhibitor to IMP-1, and their action mechanism was studied by molecular docking. Results: Twenty compounds exhibited specific inhibitory activity against IMP-1 with an IC50 value in the range of 3.1-62.5 μM. Eight of the compounds can restore the antibacterial efficacy of cefazolin against E. coli BL21 strain producing IMP-1 by 2-4 fold. ITC monitoring showed that 1c exhibited dose-dependent inhibition on IMP-1. Docking studies revealed that the triazole group in 1c and 2d played an essential role in the inhibition activity. Cytotoxicity assay showed that 1c and 2d have low toxicity in L929 mouse fibroblastic cells. Conclusion: : The triazolylthioacetamides are efficient inhibitors of IMP-1 in vitro and in vivo.

Prevalence of a Cefazolin Inoculum Effect Associated with blaZ Gene Types among Methicillin-Susceptible Staphylococcus aureus Isolates from Four Major Medical Centers in Chicago.

The efficacy of cefazolin with high-inoculum methicillin-susceptible Staphylococcus aureus (MSSA) infections remains in question due to therapeutic failure inferred as being due to an inoculum effect (InE). This study investigated the local prevalence of a cefazolin InE (CInE) and its association with staphylococcal blaZ gene types among MSSA isolates in the Chicago area. Four medical centers in Chicago, IL, contributed MSSA isolates. Cefazolin MICs (C-MIC) were determined at 24 h by the broth microdilution method using a standard inoculum (SI; 5 × 105 CFU/ml) and a high inoculum (HI; 5 × 107 CFU/ml). The CInE was defined as (i) a ≥4-fold increase in C-MIC between SI and HI and/or (ii) a pronounced CInE, i.e., a nonsusceptible C-MIC of ≥16 μg/ml at HI. PCR was used to amplify the blaZ gene, followed by agarose gel electrophoresis and sequencing to determine the gene type. Approximately 269 MSSA isolates were included. All but one isolate were susceptible to cefazolin at SI, and 97% remained susceptible at HI. A total of 196 isolates (73%) were blaZ positive, with the blaZ types led by gene type C (40%). CInE was seen in 45 blaZ-positive isolates (23%), with 44 (22%) presenting a ≥4-fold increase in C-MIC (SI to HI) and 5 (3%) a pronounced CInE. Four of the five met both definitions of CInE, two of which expressed the type A gene. The prevalence of a pronounced CInE associated with the type A blaZ gene from MSSA isolates in Chicago is low. Our predilection for cefazolin use, even early in the management of hospitalized MSSA infections, is tenable.

Inoculum effect of high concentrations of methicillin-susceptible Staphylococcus aureus on the efficacy of cefazolin and other beta-lactams.

The existence of a cefazolin inoculum effect (InE) of methicillin-susceptible Staphylococcus aureus (MSSA), which is speculated to be a reason for cefazolin treatment failure in MSSA infections, is controversial. In Japan, although cefazolin is one of the therapeutic choices for patients with MSSA infection, there are few reports of this effect. Additionally, the association between InE and blaZ type in beta-lactams other than cefazolin has not been well documented. In this study, we confirmed an MSSA InE in several beta-lactams, including cefazolin, and its relationship with blaZ, using 52 MSSA isolates from blood cultures. Three isolates (5.8%) that possessed type A blaZ showed a pronounced cefazolin InE. Five isolates (9.6%) showed pronounced InE with sulbactam/ampicillin; four isolates had type C blaZ and one had type A blaZ. However, we confirmed InE in MSSA isolates with blaZ not only type A and C but also B and D. For cefotaxime, ceftriaxone, imipenem, and meropenem, regardless of the presence of blaZ, we did not observe a significant increase in MICs at a high inoculum of MSSA. Hence, our results suggest that the above four beta-lactams are good alternatives to cefazolin if InE leads to treatment failure in a patient.

Validation of Cefazolin as Initial Antibiotic for First Upper Urinary Tract Infection in Children

To validate the policy of administering cefazolin (CEZ) as a first-line antibiotic to children who are hospitalized with their first febrile urinary tract infection (UTI), we evaluated microbial susceptibility to CEZ and the efficacy of CEZ. The 75 enrolled children with febrile UTI were initially treated with CEZ. Switching CEZ was not required in 84% of the patients. The median fever duration, prevalence of bacteremia, prevalence of UTI caused by extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, and median duration of hospitalization were significantly higher in the CEZ-ineffective group. The risks of vesicoureteral reflux, indication of operation, and renal scarring are not increased, even when CEZ is ineffective as a first-line antibiotic. CEZ is effective in more than 80% of pediatric patients with their first febrile UTI, but it should be switched to appropriate antibiotics considering sepsis or the ESBL-producing Enterobacteriaceae pathogen, when fever does not improve within 72 hours.

Prevalence of blaZ Gene Types and the Inoculum Effect with Cefazolin among Bloodstream Isolates of Methicillin-Susceptible Staphylococcus aureus

We sought to define the prevalence of blaZ gene types and the inoculum effect to cefazolin among methicillin-susceptible Staphylococcus aureus (MSSA) bloodstream infections. The blaZ gene was present in 142/185 (77%) isolates. A total of 50 (27%) isolates had a ≥4-fold increase in the cefazolin MIC from a standard to a high inoculum, and 8 (4%) demonstrated a nonsusceptible cefazolin MIC, all type A blaZ strains. The efficacy of cefazolin in the presence of the inoculum effect requires further study.

In Vitro and In Vivo Activity of First Generation Cephalosporins Against Leptospira

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.

In vitro efficacy of cefazolin and povidone‐iodine 5% in eradicating microbial organisms adhered to broad scleral buckles

<i>In vitro</i> efficacy of cefazolin and povidone‐iodine 5% in eradicating microbial organisms adhered to broad scleral buckles

Efficacy of Cefazolin in Promoting Ovine Tracheal Epithelial Repair

Inhalation of toxic materials has been shown injurious to the upper airways. Because secondary infection can slow the repair process, we undertook this study to determine the efficacy of antibiotic therapy in promoting the healing process of acute tracheal wounds. In 18 anesthetized sheep, a portion of the cervical trachea was exposed to smoke from smoldering cotton cooled to 38 degrees C. Nine received the broad-spectrum antibiotic, cefazolin, while none received saline placebo. At 13 days after injury, nonciliated and ciliated cell counts were 75% and 33% respectively of noninjured trachea receiving placebo, while in those receiving cefazolin, nonciliated and ciliated cell counts increased to 93% and 114% of paired noninjured trachea, respectively. We suggest that cefazolin therapy allows cell proliferation and differentiation to proceed more rapidly than observed with placebo therapy and thus may be a helpful augmentor to the healing of an acute airway injury.

Comparative prophylactic efficacy of cefazolin and vancomycin in a guinea pig model of Staphylococcus aureus wound infection.

The increasing prevalence of methicillin-resistant Staphylococcus aureus as a wound pathogen in some institutions has prompted the use of vancomycin for surgical prophylaxis, although clinical data comparing vancomycin and cephalosporins are not available. A guinea pig model was used to compare the efficacy of vancomycin and cefazolin in preventing intermuscular abscess formation by 7 S. aureus strains. Both antibiotics were administered to achieve peak serum levels at the time of bacterial inoculation, and each remained > 1 micrograms/mL for a comparable duration. Vancomycin provided equivalent protection from infection by 1 methicillin-susceptible strain and significantly better protection against 4 methicillin-susceptible and both methicillin-resistant S. aureus strains. For most strains, the bacterial inoculum with a 50% probability of causing an abscess was 2 to 4 log10-fold higher with vancomycin than cefazolin prophylaxis. Prophylaxis with vancomycin is superior to cefazolin in preventing intermuscular infection by methicillin-susceptible and -resistant S. aureus.