Invasive fungal infections are responsible for one-fifth of the infectious deaths in children with ALL.

The following report will discuss in detail all lethal invasive fungal infections (IFI) that occurred in a group of 2021 children with acute lymphoblasic leukaemia (ALL). The German ALL-Berlin-Frankfurt-Muenster (BFM) study group is one of the largest cooperation for the treatment of childhood ALL. Between 1995 and 2000, 2021 children with ALL received chemotherapy according to the German BFM 95 protocols (ALL-BFM 95). This population was retrospectively screened, whether a lethal fungal infection occurred: totally, in this group, 43 of 2021 (2.1%) children died because of infections. Nine of 43 (21%) patients died in the context of an IFI: six fatal Aspergillus infections and three fatal yeast infections were reported. The following report will focus on the nine children with ALL who died from IFI. The underlying risk factors (RF) included neutropenia (seven of nine patients) and steroid medication (nine of nine patients). Seven of nine children had additional medical complications (e.g. liver failure, haemolytic uraemic syndrome and acute renal failure). In six of nine children the fungal infection was progressive despite intravenous antimycotic therapy, three patients received no antifungal therapy, as IFI was not considered. The progression of IFI despite antimycotic therapy illustrates the inherent problems of diagnosis and the need for innovative therapeutic modalities. The high percentage (21%) of death from IFI among lethal infections in paediatric ALL patients illustrates the relevance of fungi in this group of patients. On the contrary, the total number of IFI in paediatric ALL patients remains to be determined, as only lethal infections were included in this report.