Table 3

Performance of echinocandin breakpoints and FKS mutations in predicting therapeutic failure

Variablea% sensitivityb% specificitycLikelihood ratio
CLSI breakpoints (intermediate isolates considered to be resistantd)
    Caspofungin BP > 0.12 μg/ml100 (10/10)0 (0/29)NAe
    Anidulafungin BP > 0.12 μg/ml30 (3/10)97 (28/29)8.7
    Micafungin BP > 0.06 μg/ml30 (3/10)90 (26/29)2.9
CLSI breakpoints (intermediate isolates considered to be sensitived)
    Caspofungin BP > 0.25 μg/ml100 (10/10)0 (0/29)NA
    Anidulafungin BP > 0.25 μg/ml30 (3/10)97 (28/29)8.7
    Micafungin BP > 0.12 μg/ml20 (2/10)97 (28/29)5.8
Epidemiologic cutoff values
    Caspofungin BP > 0.12 μg/ml100 (10/10)0 (0/29)NA
    Anidulafungin BP > 0.25 μg/ml30 (3/10)97 (28/29)8.7
    Micafungin BP > 0.03 μg/ml40 (4/10)90 (26/29)3.9
Cutoffs determined by ROC
    Caspofungin MIC > 0.5 μg/ml60 (6/10)86 (25/29)4.3
    Anidulafungin BP > 0.06 μg/ml50 (5/10)97 (28/29)14.5
    Micafungin BP > 0.03 μg/ml40 (4/10)90 (26/29)3.9
FKS genotype
    Presence of mutation60 (6/10)97 (28/29)17.4
  • a BP, breakpoint.

  • b Sensitivity is defined as the number of tests positive for the individual variable listed in the first column, divided by the number of patients who failed echinocandin therapy (n = 10) × 100%.

  • c Specificity is defined as the number of tests negative for the individual variable listed in the first column, divided by the number of patients in whom echinocandin therapy was successful (n = 29) × 100%.

  • d CLSI breakpoints define C. glabrata strains as susceptible (≤0.12 μg/ml for caspofungin and anidulafungin and ≤0.06 μg/ml for micafungin), intermediate (0.25 μg/ml for caspofungin and anidulafungin and 0.12 μg/ml for micafungin), or resistant (>0.25 μg/ml for caspofungin and anidulafungin and >0.12 μg/ml for micafungin).

  • e NA, not applicable.