Infection Characteristics
The type of infection was reported for 81% of infections (n=255/315). Of these, most infections were reported as upper respiratory infections or “viral infections” (n=137, 54%), followed by pneumonia (n=52, 20%), and cutaneous infections (n=20, 8%). Within the pneumonia category, one patient was reported to havePneumocystis jiroveciipneumonia (PJP).25 This patient was 4 months old with a diagnosis of KHE with Kasabach-Merritt Phenomenon (KMP), receiving treatment with sirolimus at 0.05 mg/kg per dose twice a day with a trough goal of 8 to 15 ng/mL. At 2 months of age, this patient was treated with vincristine, prednisolone, and propranolol. At 3 months of age, the patient discontinued vincristine and propranolol, started sirolimus, and began a steroid wean. Four weeks after initiation of sirolimus therapy, the patient developed PJP. Sirolimus was temporarily held, and the pneumonia was treated successfully with sulfamethoxazole-trimethoprim and methylprednisolone. Notably, this patient had not received PJP prophylaxis. Four cases of bacteremia (1%) were reported. Common Terminology Criteria for Adverse Events (CTCAE) grading was reported for 91% of infections. Most infections were grade 1 to 2 (n=194, 66%), and 32% (n=95) were grade 3 to 4. Six patients (n=2%) had grade 5 infections (i.e., they died as a result of infection). Most patients received antibiotic prophylaxis against PJP (n=175, 80%), while 42 (19%) did not receive prophylaxis. Of note, prophylaxis was not specified for 73 patients.