Study variables
The clinical and analytical variables were underlying disease, weight, height, age, sex, dose of micafungin administered and presence of toxicity during the prophylaxis phase.
Adverse events were analyzed according to the NCI Common Terminology Criteria for Adverse Events. Grade I/II allergic reactions consisted of skin reactions, whereas symptomatic bronchospasm requiring parenteral medication and anaphylaxis were graded as grade III and IV adverse events, respectively. Creatinine levels up to 1.5 and >1.5 (3 times the upper limit of normal (ULN)) were categorized as grade I and II adverse events, respectively, whereas levels >3–6 · ULN and >6 · ULN were categorized as grade III and IV adverse events (29).
Breakthrough fungal infection
Additionally, in children with clinical suspicion of breakthrough IFI, blood cultures and/or sterile liquid cultures were performed, as were imaging and galactomannan testing and fungal cultures of bronchoalveolar lavage samples. Galactomannan tests were not used for IFI detection because of their limited usefulness (30). Proven or probable IFIs according to the definitions of the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) were considered prophylaxis failure (breakthrough IFI) (31).