Successful Treatment of Patient With Ewing Sarcoma in the Setting of Inherited Cholestatic Liver Disease.

Progressive familial intrahepatic cholestasis type 1 (PFIC1) is an inherited, progressive cholestatic liver disease. Here, we present an approach to the treatment of Ewing sarcoma in a patient with PFIC1. The diagnosis of PFIC1 presents a unique challenge in the treatment of Ewing sarcoma, as the standard-of-care vincristine, doxorubicin, cyclophosphamide/ifosfamide and etoposide chemotherapy backbone for Ewing sarcoma therapy treatment relies heavily on intact hepatic metabolism. In addition, we report prolonged lymphopenia and severe infectious complications in this patient, both of which may be attributed to more severe immunosuppression in setting of poor hepatic metabolism of chemotherapeutic agents.

A Pilot Study of Continuous Infusion of Mycophenolate Mofetil for Prophylaxis of Graft-versus-Host-Disease in Pediatric Patients.

Mycophenolate mofetil (MMF), an ester prodrug of mycophenolic acid (MPA), is used increasingly for graft-versus-host disease (GVHD) prophylaxis. Empiric fixed-dose-escalation strategies in pediatric hematopoietic cell transplantation (HCT) recipients have failed to achieve target MPA exposure. We evaluated the safety and feasibility of a pharmacokinetics-based dosing approach using a novel continuous infusion (CI) method of administration of MMF in pediatric HCT recipients. All patients received a myeloablative conditioning with cyclosporine A and MMF for GVHD prophylaxis. MMF was initiated on day 0 at a dose of 15 mg/kg every 8 hours. Based on steady-state pharmacokinetics, MMF was converted to CI to target a total MPA AUC(0-24) of 40 to 80 µg·hour/mL. The MMF dose was adjusted to maintain a total MPA steady-state concentration (Css) of 1.7 to 3.3 µg/mL. During the CI schedule, MPA AUC(0-24) was maintained at a mean of 40.1 µg·hour/mL (range, 20.6 to 63.8), and 17 of 19 patients (89%) achieved MPA Css within target of 1.7 to 3.3 µg/mL. Eighteen of 19 patients (95%) achieved neutrophil engraftment at a median of 13 days (range, 8 to 41) post-transplant and platelet engraftment at 39 days (range, 17 to 298) days post-transplant. Six of 18 assessable patients (33%) developed stages II to IV acute GVHD and 2 of 15 (13%) developed chronic GVHD. The MMF dose was reduced in 9 patients due to gastrointestinal symptoms (n = 6), low blood counts (n = 4), and viral infection (n = 3). Five patients with acute lymphoblastic leukemia relapsed, of whom 4 have died. Fifteen of 19 patients are alive with a median follow-up of 2.4 years (range, .4 to 4.9), with 3-year event-free and overall survival rates of 68% and 79%, respectively. In this pilot study of pharmacokinetically directed MMF dosing, we observed no toxic deaths, excellent engraftment, and low rates of grades III to IV acute and chronic GVHD. We found significantly lower half-life and higher drug clearance in pediatric HCT recipients compared with stable pediatric renal transplant patients or adult transplant patients. This regimen deserves further validation in a larger cohort of pediatric patients undergoing myeloablative transplantation.

The addition of sirolimus to tacrolimus/methotrexate GVHD prophylaxis in children with ALL: a phase 3 Children's Oncology Group/Pediatric Blood and Marrow Transplant Consortium trial.

Sirolimus has activity against acute lymphoblastic leukemia (ALL) in xenograft models and efficacy in preventing acute graft-versus-host disease (aGVHD). We tested whether addition of sirolimus to GVHD prophylaxis of children with ALL would decrease aGVHD and relapse. Patients were randomized to tacrolimus/methotrexate (standard) or tacrolimus/methotrexate/sirolimus (experimental). The study met futility rules for survival after enrolling 146 of 259 patients. Rate of Grade 2-4 aGVHD was 31% vs 18% (standard vs experimental, P = .04), however, grade 3-4 aGVHD was not different (13% vs 10%, P = .28). Rates of veno-occlusive disease (VOD) and thrombotic microangiopathy (TMA) were lower in the nonsirolimus arm (9% vs 21% VOD, P = .05; 1% vs 10% TMA, P = .06). At 2 years, event free survival (EFS) and overall survival (OS) were 56% vs 46%, and 65% vs 55% (standard vs experimental), respectively (P = .28 and .23). Multivariate analysis showed increased relapse risk in children with ≥0.1% minimal residual disease (MRD) pretransplant, and decreased risk in patients with grades 1-3 aGVHD (P = .04). Grades 1-3 aGVHD were associated with improved EFS (P = .02), whereas grade 4 aGVHD and extramedullary disease at diagnosis led to inferior OS. Although addition of sirolimus decreased aGVHD, survival was not improved. This study is registered with ClinicalTrials.gov as #NCT00382109.

Phototoxic dermatoses in pediatric BMT patients receiving voriconazole.

We investigated the incidence of phototoxic skin reactions in pediatric BMT recipients treated with voriconazole. Nine out of 40 patients (22.5%), all Caucasian, developed skin lesions in sun-exposed distributions. Dermatologic findings included sunburn-like erythema, pseudo-porphyria, linear papulovesicular lesions, severe erosive cheilitis, dermatoheliosis and lentigines. Patients were treated with sun avoidance, high-potency sunscreens, and topical steroids with significant improvement in all cases. Prolonged voriconazole use requires close monitoring for chronic skin toxicities. Long-term risks including the risk of skin cancer need to be investigated.

A Quality Assessment of a Collaborative Model of a Pediatric Antimicrobial Stewardship Program.

BACKGROUND: Infectious Diseases Society of America guidelines recommend that key antimicrobial stewardship program (ASP) personnel include an infectious disease (ID) physician leader and dedicated ID-trained clinical pharmacist. Limited resources prompted development of an alternative model by using ID physicians and service-based clinical pharmacists at a pediatric hospital. The aim of this study was to analyze the effectiveness and impact of this alternative ASP model. METHODS: The collaborative ASP model incorporated key strategies of education, antimicrobial restriction, day 3 audits, and practice guidelines. High-use and/or high-cost antimicrobial agents were chosen with audits targeting vancomycin, caspofungin, and meropenem. The electronic medical record was used to identify patients requiring day 3 audits and to communicate ASP recommendations. Segmented regression analyses were used to analyze quarterly antimicrobial agent prescription data for the institution and selected services over time. RESULTS: Initiation of ASP and day 3 auditing was associated with blunting of a preexisting increasing trend for caspofungin drug starts and use and a significant downward trend for vancomycin drug starts (relative change -12%) and use (-25%), with the largest reduction in critical care areas. Although meropenem use was already low due to preexisting requirements for preauthorization, a decline in drug use (-31%, P = .021) and a nonsignificant decline in drug starts (-21%, P = .067) were noted. A 3-month review of acceptance of ASP recommendations found rates of 90%, 93%, and 100% for vancomycin, caspofungin, and meropenem, respectively. CONCLUSIONS: This nontraditional ASP model significantly reduced targeted drug usage demonstrating acceptance of integration of service-based clinical pharmacists and ID consultants.

Ketamine PCA for treatment of end-of-life neuropathic pain in pediatrics.

Control of neuropathic pain (NP) for children at end of life is challenging. Ketamine improves control of NP, but its use in children is not well described. We describe a retrospective case review of 14 children with terminal prognoses treated with ketamine patient-controlled analgesia (PCA) for management of opioid-refractory NP at the end of life. Median ketamine dose was 0.06 mg/kg/h (range 0.014-0.308 mg/kg/h) with a 0.05 mg/kg (range 0.03-0.5mg/kg) demand dose available every 15 minutes (range 10-60 minutes). All patients noted subjective pain relief with ketamine, and 79% had no adverse effects. Benzodiazepines limited neuropsychiatric side effects. Ketamine treatment arrested dose escalation of opioids in 64% of patients, and 79% were discharged to home hospice. Ketamine PCA is an effective, well-tolerated therapy for opioid-refractory NP in pediatric end-of-life care.