60th NMC – National Mastitis Council Association between antimicrobial use and antimicrobial resistance of Streptococcus uberis causing clinical mastitis Larissa Martins¹, Renata de Freitas Leite 1 , Juliano Leonel Gonçalves 1 , Tiago Tomazi 2 , Marcos Veiga dos Santos 1 1 School of Veterinary Medicine and Animal Science, University of Sao Paulo 2 Department of Population Medicine and Diagnostic Sciences, Cornell University January, 2021
24
Embed
Association between antimicrobial use and antimicrobial ...
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
60th NMC – National Mastitis Council
Association between antimicrobial use and antimicrobial resistance of Streptococcus uberis
1 School of Veterinary Medicine and Animal Science, University of Sao Paulo2Department of Population Medicine and Diagnostic Sciences, Cornell University
Antimicrobial use (AMU) and Antimicrobial resistance (AMR)
• Saini et al., 2012: Staphylococcus aureus
• Saini et al., 2013: Gram-negative
• Nobrega et al., 2018: non-aureus staphylococci
Streptococcus uberis
https://qualileite.org/
2. Objectives
Oliv
ia d
e R
iva
z
2. Objectives
➢The aim of this study was to investigate theassociation between AMU and AMR evaluatingthe susceptibility profile of Strep. uberis toantimicrobials commonly used in CM treatment
✓Cow´s identification✓Affected mammary quarter✓Date✓Antimicrobial commercial name✓Number of administrations✓Description of protocol changes during
the treatment
3. Material and Methods
Antimicrobial consumption data (17 dairy herds)
• Number of defined daily doses (DDD)
• Antimicrobial Treatment Incidence (ATI)
https://qualileite.org/
✓ Intramammary and Systemic antimicrobials
ATI = Total amount of active substance (mg) used in a givenmonth
DDD X number of lactating cows in a givenmonth x days in a monthx 1,000
✓ Estimated for each farm and expressed as the number of DDD used for CM treatmentper 1,000 lactating cow-days at risk
3. Material and Methods
Statistical Analysis
• MIC Assays
• AMU and AMR
https://qualileite.org/
✓ Susceptible or Resistant✓ PROC FREQ– SAS✓ P<0.05
✓ Association between the overall use of antimicrobials and resistance of isolates toeach antimicrobial used in the susceptibility test
✓ Association between antimicrobial use stratified by class and the antimicrobialresistance of the isolates to the same antimicrobial class
✓ PROC GLIMMIX - SAS✓ P<0.05
4. Results
Oliv
ia d
e R
iva
z
4. Results
https://qualileite.org/
Antimicrobial Susceptible2 Resistant3
Gentamicin 15.68% 84.32%
Cefalexin 71.09% 28.91%
Ceftiofour 89.15% 10.85%
Lincomicin 26.49% 73.51%
Erythromycin 19.28% 80.72%
Amoxicillin 79.52% 20.48%
Ampicillin 79.51% 20.49%
Penicillin 36.14% 63.86%
Ciprofloxacin 68.67% 31.33%
Enrofloxacin 93.97% 6.03%
Oxitetracycline 4.84% 95.16%
Tetracycline 48.17% 51.83%
Percentage of Streptococcus uberis classified as susceptible orresistant by antimicrobial tested¹
1In vitro tests considering (n = 83) Streptococcus uberis isolates2Susceptible, high probability of therapeutic success according to the standard dosing related to the pathogen3Resistant, high probability of therapeutic fail even with adjustments in the exposure of the pathogen to the antimicrobial
4. Results
https://qualileite.org/
Percentage of Streptococcus uberis classified as susceptible orresistant by antimicrobial classes¹
1In vitro tests considering (n = 83) Streptococcus uberis isolates2Susceptible, high probability of therapeutic success according to the standard dosing related to the pathogen3Resistant, high probability of therapeutic fail even with adjustments in the exposure of the pathogen to the antimicrobial
≥3 antimicrobial classes
Antimicrobial class Susceptible2 Resistant3
Tetracyclines 26.51 73.49
Quinolones 62.72 37.28
Cephalosporins 79.76 20.24
Macrolides 19.05 80.95
Aminoglycosides 19.05 80.95
Penicillins 69.4 30.96
Lincosamides 26.49 73.51
85%Multi-resistant
4. Results
https://qualileite.org/
Antimicrobial class Number of herdsATI (DDD x 1,000 )
Average SD
Tetracyclines 15 5.0 5.8
Quinolones 14 4.7 6.0
Cephalosporins 16 3.8 6.0
Macrolides 7 3.2 6.3
Aminoglycoside 8 2.4 4.8
Penicillins 16 1.8 3.6
Antimicrobial treatment incidence (ATI) and frequency of herdswith reported use of antimicrobial classes administered byintramammary and systemic routes in 17 dairy herds fromSoutheastern Brazil
4. Results
https://qualileite.org/
Antimicrobial class Number of herdsATI (DDD x 1,000 )
Average SD
Tetracyclines 15 5.0 5.8
Quinolones 14 4.7 6.0
Cephalosporins 16 3.8 6.0
Macrolides 7 3.2 6.3
Aminoglycoside 8 2.4 4.8
Penicillins 16 1.8 3.6
Antimicrobial treatment incidence (ATI) and frequency of herdswith reported use of antimicrobial classes administered byintramammary and systemic routes in 17 dairy herds fromSoutheastern Brazil
• ATI = 23.7 DDD x 1,000 lactating dairy cows
5 – 55.4
https://qualileite.org/
Antimicrobials tested Antimicrobial class Estimate SE1 P-value OR2 95% CI3
Association between overall antimicrobial treatment incidence stratified by class and resistance ofStreptococcus uberis to antimicrobials used for susceptibility testing
The overall use of antimicrobial was not associated with the overall resistance of Strep. uberis
BUT...
5. Conlusions
Oliv
ia d
e R
iva
z
5. Conclusions
✓ Cephalosporins and penicillins were the most common antimicrobialsused by the 17 herds evaluated in the present study
✓ Although some isolates presented resistance to antimicrobials, theoverall use of antimicrobials was not associated to the overallresistance of Strep. uberis
✓ However, when the data were stratified according to the antimicrobialclasses there was an increase of Strep. uberis resistance to tetracyclines