F female, M male, HSCT: hematopoietic stem cell transplant, PID primary immunodeficiency, B-ALL: B cell acute lymphoblastic leukemia, T-ALL T cell acute lymphoblastic leukemia, Tx transplant, HCQ hydroxychloroquine, IS immunosuppressors, LPV/Rtv lopinavir/ritonavir, O2 oxygen; HLH hemophagocytic lymphohistiocytosis. MMF mycophenolate
*HCQ was initiated in patients 1, 3, 4, and 8 once confirmation of positive SARS-CoV-2 with a nasal swab was obtained (< 24 h from consultation at our hospital). Patients 1, 3, and 8 attended the Emergency Department in the first 24 h after onset of symptoms. Patient 4 had fever of 4 days when the nasal swab was obtained, and patient 7 received 5 days of LPV/Rtv initially and due to persistent symptoms was switched to HCQ. According to our guidelines, the oral dose was as follows: HCQ 6.5 mg/kg/day (dosing q12 h) in 6 year-olds, and HCQ 10 mg/kg/day (dosing q12 h) in children > 6 years (maximum daily dose 400 mg) for 5 days
**Remdesivir was given for a total of 7 days on patient 1 and 10 days on patient 4, at an intravenous dose of 5 mg/kg on day 1, followed by a maintenance dose of 2.5 mg/kg from days 2 to 9 (patients <40 kg) or 200 mg/iv on day 1 followed by 100 mg/iv on days 2-9 (for patients >40 kg)
***Dexamethasone was given as per the HLH 2004 trial, although with a shorter duration: 10 mg/m2/day for 7 days, followed by 5 mg/m2/day for another 7 days, followed by 2.5 mg/m2 for 7 days and 1.25 mg/m2 for 2 days and then a tapering dose with hydrocortisone