MedElevator
Войти в исследования Journal of global antimicrobial resistance · 2026
Association between the blaZ gene and the cefazolin inoculum effect among bloodstream isolates of methicillin-susceptible Staphylococcus aureus.
СтатьяНазвание и аннотация: Перевод в очереди
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Zhu Wenyan, Yang Qing, Xiao Yanyan, Jia Huiqiong, Chen Yuqing, Gu Yaxi, Li Shengchao, Qu Yahong
Аннотация
OBJECTIVE: Investigating the incidence of the cefazolin inoculum effect (CzIE) in methicillin-susceptible Staphylococcus aureus and its correlation with the blaZ gene.
METHODS: Genotyping and blaZ gene detection using Sanger sequencing were conducted on 113 methicillin-susceptible S. aureus (MSSA) isolates from bloodstream infections at a tertiary hospital in Hangzhou, Zhejiang Province, collected from January 2021 to October 2024. Cefazolin susceptibility was determined using the broth microdilution method under standard (5 × 105 CFU/mL) and high (5 × 107 CFU/mL) inoculum conditions. Statistical analysis was performed using SPSS Statistics 29.0.
RESULTS: Among the 113 MSSA strains, 94 carried the blaZ gene, with the highest proportion being type C (57/94, 60.6%), followed by type A (21/94, 22.4%), type B (16/94, 17.0%), and no type D was detected. The overall CzIE prevalence was 12.4% (14/113). blaZ type A isolates exhibited a significantly higher CzIE rate (42.9%, 9/21) compared to type B (0%, 0/16) and type C (9.8%, 5/57) (P < 0.0167).
CONCLUSIONS: The incidence of CzIE in MSSA was 12.4%. While blaZ type C was the most common, blaZ type A exhibited the most significant correlation with CzIE. Clinicians must remain alert for blaZ type A strains, as their significant inoculum effect may elevate the probability of cefazolin treatment failure in severe MSSA infections.
METHODS: Genotyping and blaZ gene detection using Sanger sequencing were conducted on 113 methicillin-susceptible S. aureus (MSSA) isolates from bloodstream infections at a tertiary hospital in Hangzhou, Zhejiang Province, collected from January 2021 to October 2024. Cefazolin susceptibility was determined using the broth microdilution method under standard (5 × 105 CFU/mL) and high (5 × 107 CFU/mL) inoculum conditions. Statistical analysis was performed using SPSS Statistics 29.0.
RESULTS: Among the 113 MSSA strains, 94 carried the blaZ gene, with the highest proportion being type C (57/94, 60.6%), followed by type A (21/94, 22.4%), type B (16/94, 17.0%), and no type D was detected. The overall CzIE prevalence was 12.4% (14/113). blaZ type A isolates exhibited a significantly higher CzIE rate (42.9%, 9/21) compared to type B (0%, 0/16) and type C (9.8%, 5/57) (P < 0.0167).
CONCLUSIONS: The incidence of CzIE in MSSA was 12.4%. While blaZ type C was the most common, blaZ type A exhibited the most significant correlation with CzIE. Clinicians must remain alert for blaZ type A strains, as their significant inoculum effect may elevate the probability of cefazolin treatment failure in severe MSSA infections.