Differential diagnosis of an apparent failure of antifungal therapy:
(1) overwhelming fungal infection
(2) impaired host defenses (neutropenia, immunosuppression, etc)
(3) primary antifungal resistance
(4) acquired antifungal resistance (selection of resistant clones, other)
(5) wrong diagnosis
(6) mixed infection
(7) improper choice of antifungal therapy
(8) inadequate dose of the antifungal agent(s)
(9) poor delivery of antifungal agent to site of infection (poor perfusion, biofilm, other)
(10) drug-drug interaction negatively impacting drug delivery
(11) poor absorption or increased elimination of the antifungal agent (pharmacodynamic problem)
(12) immune reconstitution inflammatory syndrome (IRIS)
(13) adverse drug reaction
(14) clinical deterioration associated with severe comorbid conditions
(15) reaching the conclusion of failure too early (not enough time for effect to be manifest)
(16) failure to treat a surgical disorder (need to debride, remove an implant, etc)
