No abstract

There is a paucity of information about the clinical characteristics and long‐term outcomes of pediatric epithelioid hemangioendothelioma (EHE), a rare vascular neoplasm commonly presenting in adulthood. In our case series of 24 patients with EHE aged 2‐26 years, the majority presented with multi‐organ disease. Progression was seen in 63% of patients with a mean time to progression of 18.4 months (range: 0‐72). Three patients treated with sirolimus achieved stable disease or partial response for >2.5 years. Longitudinal prospective pediatric studies are needed to develop standardized approaches to surgical and medical management.

Background: Postthrombotic syndrome (PTS) is a significant complication of pediatric deep venous thrombosis (DVT). There is a gap in the understanding of the risk factors associated with the development of pediatric PTS preventing the early identification of those patients at greatest risk, and the development of risk-stratified interventions. Objectives: To conduct a systematic review and meta-analysis of the literature on prognostic factors for PTS development in pediatric patients. Methods: A systematic search of MEDLINE, EMBASE, and the Cochrane Library from 1960 to December 2018 was performed. Eligible studies reported at least one prognostic factor for PTS development in patients < 21 years of age with a radiographically confirmed DVT. To be included in the meta-analysis, prognostic factors had to be reported in at least three published studies. Results and conclusions: Twelve studies (n = 1160 patients) met criteria for inclusion. Ninety-three percent of patients with an extremity DVT (n = 1076) were assessed for PTS. PTS developed in 40% (n = 434) of these patients. Central venous catheter-associated DVT (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.08-2.98), complete venoocclusion (OR, 1.89; 95% CI, 1.04-3.46), and incomplete DVT resolution (OR, 2.07; 95% CI, 1.4-3.07) were identified as candidate prognostic factors for pediatric PTS. These findings should be interpreted in the context of the heterogeneity of the included studies and the limitations of current pediatric PTS assessment tools. Further, the predictive value of these prognostic factors will need to be validated in future collaborative prospective multicenter studies that maximize the homogeneity of pediatric DVT patients.

Epithelioid hemangioendothelioma (EHE) is a rare malignant vascular tumor with no standardized treatment. The mammalian target of rapamycin inhibitor, sirolimus, has been used successfully in adult EHE and other vascular tumors in children but has not been studied in pediatric EHE. The aim of this retrospective case series is to discuss the results of sirolimus for treatment in 6 pediatric patients with EHE. Four of 6 patients demonstrated partial response or disease stabilization with sirolimus treatment. No treatment dosing, trough goals, or duration of treatment recommendations can be made. Prospective studies are warranted to further investigate the use of sirolimus in treatment of EHE.

Rituximab and eculizumab, monoclonal antibodies that deplete most B cells and activate the terminal complement, respectively, are used to treat nonmalignant hematologic disorders (NMHDs), sometimes with unfavorable effects on the immune system. Hypogammaglobulinemia and neutropenia have been reported with variable prevalence in patients treated with rituximab. Neutropenia is mild and transient, and serious infectious complications are uncommon, so treatment is not indicated. Hypogammaglobulinemia is of greater concern. There is a lack of agreement on a standardized definition, and pre- and posttreatment immunoglobulin (Ig) levels are not routinely obtained. The association among low Ig levels, infectious risk, and mortality and morbidity in this population is unclear. There are also no formal guidelines on indication, risk factors, and threshold level of IgG to prompt Ig replacement therapy (IgRT). Among patients with NMHD, preexisting or persistent hypogammaglobulinemia (PH) after treatment with rituximab has been linked to underlying primary immunodeficiency disorders; therefore, a high index of suspicion should be maintained, and immunologic and genetic evaluation should be considered. Overall, important strategies in managing patients who are receiving rituximab include routine monitoring of pre- and posttreatment IgG levels, immune reconstitution (eg, B-cell subsets), assessment of vaccination status and optimization before treatment, and individualized consideration for IgRT. Accordingly, we discuss immunizations. Eculizumab, most commonly used in the treatment of paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome, poses increased risk of meningococcal infections. To decrease the risk of infection, a meningococcal vaccination series is recommended before initiating therapy, and prophylactic antibiotics are preferred during the course of treatment.