High Melphalan Exposure Increases the Risk of Graft-Versus-Host Disease in Pediatric Patients Undergoing Alpha-Beta T-Cell Depleted Haploidentical Transplantation.

Background: Melphalan is often used as the backbone agent for conditioning prior to A/B-T-cell depleted (A/B-TCD) hematopoietic cell transplant (HCT) due to lower rates of organ toxicity compared to busulfan or total-body irradiation, albeit with significant mucosal injury. Traditional dosing based on body-surface-area (BSA) may result in non-optimal melphalan exposure among certain patient subsets.

Objectives: As mucosal injury is linked to initiation of alloreactivity, we hypothesized that high exposure of melphalan predicted via a pharmacokinetic (PK) model would be associated with an increased risk of acute graft-versus-host disease (aGVHD).

Younger children with nonmalignant disease have increased incidence of mixed myeloid chimerism after allogeneic hematopoietic cell transplantation with busulfan-based conditioning.

Successful allogeneic hematopoietic cell transplantation (HCT) for genetic nonmalignant diseases (NMD) is dependent upon elimination of host hematopoietic stem cells (HSCs) and replacement with donor HSCs in stable numbers sufficient to correct the underlying disease. Donor myeloid chimerism (DMC) in peripheral blood (PB) is a surrogate marker for bone marrow HSC engraftment due to the rapid turnover of PB myeloid cells. Busulfan is commonly used during conditioning for patients with NMD, though its optimal exposure to avoid inadequate DMC is not fully known.

Prevent Acute Chest Syndrome checklist (PACScheck): A quality improvement initiative to reduce acute chest syndrome.

Background: Acute chest syndrome (ACS) is a life-threatening complication of sickle cell disease (SCD). The Prevent Acute Chest Syndrome checklist (PACScheck) was created to drive appropriate ordering of opioids, incentive spirometry (IS), intravenous fluids (IVF), evaluation of oxygen desaturation, and bronchodilator use.

Objectives: Decrease the development of ACS by 5% in a hospitalized pediatric SCD population.

Recurrent Atypical Hemolytic Uremic Syndrome in Children With Acute Lymphoblastic Leukemia Undergoing Maintenance Chemotherapy.

Chemotherapy-associated myelosuppression and renal dysfunction is not uncommon during childhood acute lymphoblastic leukemia (ALL) therapy. Here we report 2 cases of atypical hemolytic uremic syndrome (aHUS) presenting with pancytopenia and renal dysfunction that developed during maintenance chemotherapy characterized by hypocomplementemia. Both cases experienced recurrence after resolution of the initial aHUS episode upon resumption of chemotherapy, raising a possible contributory role for chemotherapy in the disease pathogenesis.