Quick Update: Is this the End of Humanity? - Ceftriaxone and Azithromycin "Resistant" Neis
Leading photo: microbeonline.com
UPDATE: they finally determined endpoint MICs
CRO = 0.5
AZT > 256
This is the real deal y'all.
Public Health England reported an imported case of N. gonorrhoeae infection with treatment failure (CRO only, followed by SPT)
Not treated with double regimen (CRO+AZT)
Genital infection was cured, but throat was persistently positive
Not a surprise since throat infections are harder to get rid of, and ALL reported cases of CRO failure so far have exclusively been pharyngeal infections
Caused by a bug with:
CRO MIC > 0.125
EUCAST breakpoint for R: >0.125
CLSI breakpoint for R: >0.25
AZT MIC > 0.5
EUCAST breakpoint for R: >0.5
CLSI epidemiological cutoff (ECV) for NWT: >=2
End point MICs were not reported, so we don't know if this bug would be considered R/NWT for both drugs when using CLSI breakpoints/ECVs
Currently treated with ETP IV: based on MIC 0.032, but no breakpoint exists
Is this terrifying? Yes, but there are things to consider
Hawaii Department of Public Health has reported isolates with CRO MICs 0.125 by agar dilution and AZT MIC > 256, yet these infections were successfully treated with double regimen
Hawaii paper did not specify whether these include pharyngeal infections, and if so, whether treatment was successful
Would this UK case have been successfully treated with the double regimen? We'll never know
UK uses EUCAST BPs, which are lower than CLSIs
Let's wait and see how this turns out.......