Background: Pediatric hematology-oncology (PHO) and bone marrow transplantation (BMT) units have high use of antimicrobials. Objectives: To survey antimicrobials used in Greek PHO and BMT units before and after an intervention involving education on the 2017 clinical practice guidelines (CPG) for the management of febrile neutropenia in children with cancer and hematopoietic stem cell transplant recipients. Methods: Antibiotic prescribing practices were prospectively recorded between June 2016 and November 2017. In December 2017, education for the CPG took place and antibiotic prescribing practices were followed for one more year. For antibiotic stewardship, days of therapy and length of therapy were calculated. Results: Five of six PHO units and the single pediatric BMT unit covering >92% of children with hematologic and oncologic diseases in Greece participated. Administration of ≥ 4 antibiotics simultaneously and of antibiotics with overlapping activity for ≥ 2 days was significantly more common in PHO units located in general compared to pediatric hospitals. Use of at least one antifungal was recorded in approximately 47% of the patients before and after the intervention. De-escalation and/or discontinuation of antibiotics on day 6 of initial treatment increased significantly from 43% to 53.5% (p=0.032). Although the number of patients requiring support in the intensive care unit for sepsis did not change, a significant drop was noted in all-cause mortality after the intervention (p=0.008). Conclusion: Our surveillance was able to accurately document the antibiotic prescribing practices of Greek PHO and BMT units. Moreover, it identified areas in immediate need for improvement in antibiotic stewardship.

Immune thrombocytopenia (ITP) is well described in children and commonly associated to recent viral infections. We present a 15-year-old male and a 3.5-year-old female with ITP secondary to COVID-19. Both patients presented with bruises, epistaxis and low platelet count. Both were successfully treated with a single dose of intravenous immunoglobulin. They had a history of asymptomatic (the first) and mild (the second), molecularly confirmed, COVID-19 infection three and five weeks prior to thrombocytopenia respectively, raising the possibility of a causal association between SAR-COV-2 and ITP. This linkage is rare and remains a field to be further explored.