Objectives: To assess the safety of enteral nutrition (EN) in children on extracorporeal membrane oxygenation (ECMO). To describe nutritional status and the characteristics of the nutritional support in this population. Methods: A retrospective single-center analysis (2006–2016) including children <18 years on ECMO. Demographic data, nutritional status, characteristics of nutritional support, and development of gastrointestinal (GI) complications were recorded. Results: One hundred children, with a median age of 9.7 months (interquartile range [IQR] 3.9–63.1) were enrolled. Undernutrition was prevalent among children on ECMO (33.3%) mainly in patients <2 years ( P = 0.042). Most patients (64%) received EN at some point during ECMO therapy. EN was administered in the first 48 hours after ECMO initiation (48HEN) to 60.3% of the children. Mortality rate in the Pediatric Intensive Care Unit was lower in patients who received EN as the initial artificial nutrition support (ANS) (37.7 vs 51%, P = 0.005) and in children on 48HEN (34% vs 50%, P = 0.04). In the logistic regression analysis, duration of ECMO support and low cardiac output indication were the only factors associated with mortality. Although most patients on ECMO (45%) developed digestive complications, they were mostly mild, being constipation the most prevalent. In the logistic regression analysis, EN was not associated with an increase in GI complications ( P = 0.09). Only three patients developed intestinal ischemia (one without EN and two on EN). Conclusions: Undernutrition is prevalent among children on ECMO, mainly in infants <2 years. EN is not associated with severe gastrointestinal complications or higher mortality in these children.

Introduction: Calreticulin (CALR) is a multifunctional protein regulated by calcium that is located in the endoplasmic reticulum. Recently, mutations in the calreticulin gene have been described in patients with the diagnosis of essential thrombocytemia (ET) and primary myelofibrosis (PMF), mainly in JAK2-negative cases. CALR mutations are localized to exon 9 and generate deletions or insertions that lead to a frameshift change resulting in a mutant protein. The detection of these mutations helps in the actual diagnosis of JAK2 mieloproliferative syndromes (MPN). Our aim is to assess the utility of the determination of these mutations in the management of patients with diagnosis of MPN in our center. Patients and methods: This study includes 94 patients with diagnosis of JAK2-negative MPN retrospectively selected following clinical and analytical criteria between 2008 and 2014 in our center (Table 1, 2). CALR mutations were performed with the use of fluorescent PCR following the methods described by Klampf et al. (NEJM, 2013). Results: 94 patients were analyzed, 77 of them had the diagnosis of TE, 8 of PMF and 9 of others disorders of myelodisplastic/mieloproliferative. 22% of the cases of ET had mutations in CALR (Table 1). In these mutations, a total of 53% were type I mutations (52-bp deletion) and 47% were type II mutations (5-bp insertion). Only one mutation was infrequent, a 46-pb deletion. We have found statistical correlation in the number of platelets depending on the presence of the mutation and in the largest number of platelets in type II mutations. 33% of the cases of PMF had mutations in CALR, all of them type I. Among other diseases not included in MPN, one of them had a type I mutation (data not shown). Conclusions: Our results are close to recently published results regarding the frequency of mutation and as the largest number of platelets in type II mutations with respect to mutation type I. This study confirms the importance of CALR mutations determination in the diagnosis of JAK2-negative ET and PMF with high clinical suspicion. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.