Related Experiment Videos
Aminoglycoside resistance among blood culture isolates
Abstract:
A total of 633 blood culture isolates were collected from 1981 to 1982 from seven major Finnish hospitals, including all university central hospitals. Susceptibility of the strains to gentamicin, tobramycin, amikacin, and netilmicin was determined by the Sensititre microtiter procedure. Resistance against any of these agents occurred in 1.3 to 6.5% of all strains studied. In the Turku University Central Hospital, an increased number of tobramycin- and gentamicin-resistant Staphylococcus epidermidis were found; the frequency of strains resistant to tobramycin was 57% and to gentamicin was 29% versus frequencies of 16 and 18%, respectively, which were observed in the other hospitals. An explanation for this might be a change in the use of aminoglycosides in the Turku University Central Hospital; within 3 years, 1979 to 1981, the consumption of tobramycin and amikacin had increased 330 and 290%, respectively, whereas the use of gentamicin had decreased to 24% of that in the beginning of the period. Resistance against tobramycin was mediated by enzymes APH(2")-AAC(6') and ANT(4').
Insights
High rates of tobramycin and gentamicin resistance in Staphylococcus epidermidis were observed in one Finnish hospital, potentially linked to increased aminoglycoside use. This study highlights the impact of antibiotic consumption on antimicrobial resistance patterns.
Area of Science:
- Clinical Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Aminoglycoside antibiotics are crucial for treating serious bacterial infections.
- Monitoring antimicrobial resistance patterns is essential for effective treatment strategies.
- Staphylococcus epidermidis is a common cause of hospital-acquired infections.
Purpose of the Study:
- To determine the prevalence of resistance to gentamicin, tobramycin, amikacin, and netilmicin in blood culture isolates.
- To investigate regional variations in aminoglycoside resistance, particularly in Staphylococcus epidermidis.
- To explore the potential correlation between aminoglycoside consumption and resistance development.
Main Methods:
- Collected 633 blood culture isolates from seven major Finnish hospitals between 1981 and 1982.
- Determined antimicrobial susceptibility using the Sensititre microtiter procedure.
- Analyzed aminoglycoside consumption data from Turku University Central Hospital.
Main Results:
- Overall resistance to the tested aminoglycosides ranged from 1.3% to 6.5%.
- Turku University Central Hospital showed significantly higher rates of tobramycin (57%) and gentamicin (29%) resistance in Staphylococcus epidermidis compared to other hospitals (16% and 18%, respectively).
- Increased consumption of tobramycin (330%) and amikacin (290%) and decreased gentamicin use were noted in Turku prior to the resistance findings.
- Tobramycin resistance was mediated by specific aminoglycoside-modifying enzymes: APH(2")-AAC(6") and ANT(4").
Conclusions:
- A localized increase in aminoglycoside use may drive the emergence of resistant Staphylococcus epidermidis strains.
- Continuous surveillance of antibiotic resistance and consumption is vital to guide antimicrobial stewardship.
- Understanding resistance mechanisms is key to developing strategies against emerging antimicrobial resistance.