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Key Points• Upper limb PTS in children depends on DVT pathogenesis (primary vs secondary) and on the age of the patient (neonates vs non-neonates).• DVT pathogenesis and thrombus resolution are independent predictors of upper limb PTS in children.Despite its relatively estimated high occurrence, the characterization of pediatric upper extremity deep vein thrombosis (UE-DVT) and of UE postthrombotic syndrome (PTS) is still lacking. We investigated the occurrence, characteristics, and predictors of UE-PTS in a cohort of children with objectively confirmed UE-DVT. Patients were analyzed in 3 groups according to DVT pathogenesis and neonatal status: primary (G1), secondary neonates (G2 neonates ), and non-neonates (G2 non-neonates ). A total of 158 children (23 G1, 25 G2 neonates , and 110 G2 non-neonates ) were included. The most common triggering factors were effort-related (87%) in G1 and central lines in G2 neonates (100%) and in G2 non-neonates (92%). PTS scores ‡1, as per the Modified Villalta Scale, were identified in 87% of primary patients, 16% of G2 neonates , and 49% of G2 non-neonates . Survival analysis showed that the time to PTS score ‡1 significantly differed among group (log-rank test P < .0001).A multivariable logistic regression showed that DVT pathogenesis and imaging-determined degree of thrombus resolution at the end of therapy were independent predictors of a PTS score ‡2. In conclusion, pediatric UE-PTS frequency and severity depend on UE-DVT pathogenesis (primary/secondary) and, within the secondary group, on patient's age. Line-related UE-PTS has a more benign course, particularly in neonates. (Blood. 2014;124(7):1166-1173

BackgroundThe aim of this paper is twofold: (1) to describe the fundamental differences between formative and reflective measurement models, and (2) to review the options proposed in the literature to obtain overall instrument summary scores, with a particular focus on formative models.MethodsAn extensive literature search was conducted using the following databases: MEDLINE, EMBASE, PsycINFO, CINAHL and ABI/INFORM, using “formative” and “reflective” as text words; relevant articles’ reference lists were hand searched.ResultsReflective models are most frequently scored by means of simple summation, which is consistent with the theory underlying these models. However, our review suggests that formative models might be better summarized using weighted combinations of indicators, since each indicator captures unique features of the underlying construct. For this purpose, indicator weights have been obtained using choice-based, statistical, researcher-based, and combined approaches.ConclusionWhereas simple summation is a theoretically justified scoring system for reflective measurement models, formative measures likely benefit from the use of weighted scores that preserve the contribution of each of the aspects of the construct.Electronic supplementary materialThe online version of this article (doi:10.1186/s13104-015-1561-6) contains supplementary material, which is available to authorized users.

Key Points• The frequency of PTS, PE, and DVT recurrence was higher in children with Non-LR DVT than in children with LR DVT.• Thrombus resolution, DVT triggering event, and sex were predictors of LE PTS in children.Pediatric lower extremity deep vein thrombosis (LE-DVT) can lead to postthrombotic syndrome (PTS) and other adverse events. We investigated the outcomes of LE-DVT in children. Three groups were compared: non-line-related (Non-LR) DVT, LR DVT in neonates (LR neonates ), and LR DVT in non-neonates (LR non-neonates ). A total of 339 children were included (Non-LR, n 5 56; LR neonates , n 5 95; and LR non-neonates , n 5 188). We found a statistically significant difference in the frequency of PTS (P 5 .04; 62.5%, 40.0%, and 46.3% in Non-LR, LR neonates , and LR non-neonates, respectively), of recurrent LE-DVT (P 5 .001; 10.7% and 2.0% in Non-LR and LR non-neonates, respectively), and pulmonary embolism (PE) (P < .001; 19.6% and 3.2% in Non-LR and LR non-neonates, respectively) among groups. There was no difference in DVT resolution (P 5 .41). Multivariable analysis showed that DVT resolution, triggering event, and sex predicted Modified Villalta Scale (MVS; for pediatric PTS) scores >1; there was an interaction between DVT triggering event and sex. The time to reach an MVS >1 was significantly different when comparing groups (log-rank test, P < .001). Moreover, we found a significant difference in baseline MVS scores among groups, but the difference did not appear to change over time. In conclusion, LR LE-DVT had more benign outcomes than Non-LR DVT. Sex, DVT triggering event, and DVT resolution predicted

CanadaTo cite this article: Avila ML, Shah V, Brandão LR. Systematic review on heparin-induced thrombocytopenia in children: a call to action. J Thromb Haemost 2013; 11: 660-9.Summary. Background: Heparin-induced thrombocytopenia (HIT) has increasingly been reported in children as an indication for use of new alternative anticoagulant drugs (NAADs). Objectives: To systematically review the literature regarding: (i) the incidence and prevalence of seroconversion and HIT and (ii) the clinical/laboratory findings and management of HIT in children. Design/ Methods: MEDLINE and EMBASE databases were searched for studies that reported pediatric cases of HIT. Methodological reliability assessment of studies was performed with the Loney scale. Results: The incidence of seroconversion in neonates ranged between 0% and 1.7%. There were no cases of neonatal HIT in the included cohorts. The incidence range of seroconversion in the non-neonatal population was 1.3-52%. The incidence of HIT in non-neonates after cardiopulmonary bypass was 0.33% (95%CI, < 0.01-2.04). Whereas more than half of pediatric cases labeled as HIT (30/52) did not include pivotal features of this syndrome, 80% of them received NAADs. Conclusion: The incidence of HIT is likely to have been overestimated in children, leading to potential misuse of NAADs in many cases. Clinical findings and laboratory assessment of pediatric cases are poorly described in the literature at present. Thorough laboratory investigation, proper reporting of cases and adequate design of studies are mandatory to elucidate the clinical/laboratory picture of pediatric HIT.

Background Postthrombotic syndrome (PTS) is a complication of deep vein thrombosis defined by the presence of characteristic signs and symptoms. We developed a discriminative and evaluative index for the assessment of upper extremity (UE) and lower extremity (LE) pediatric PTS. Methods The items to be included in the index were voted for by 26 pediatric thrombosis experts invited to participate in a Delphi survey. Subsequent item weighting was based on item importance elicited by the use of multicriteria decision analysis (MCDA); 122 healthcare providers and patients/parents were invited to participate in item weighting. The implications of the overall scores were explored by comparison with PTS diagnosis (independently assessed by two clinical experts) and parental satisfaction/dissatisfaction with their child's current condition. Results Items voted for inclusion by at least 70% of the Delphi survey respondents (81% response rate) were pain, paresthesia, swelling, heaviness, endurance, collateral circulation and arm circumference difference for the UE, and pain, paresthesia, swelling, heaviness, tightness, tired limb, redness/purple or blotchy skin, endurance, ulcers and thigh/calf circumference difference for the LE. Items were then weighted by the use of MCDA (82% response rate). The index had excellent discrimination for patients with/without PTS. For every 10-point increase in index scores (with higher scores being indicative of worse PTS), the odds of parental dissatisfaction increased by 75% and 92% in the UE and LE, respectively. Conclusion We report the development of the CAPTSure™ (index for the Clinical Assessment of Postthrombotic Syndrome in children), which reflects collective judgement of the severity of pediatric PTS. We also provide information on the meaning of the scores.

The role of thrombophilia testing in predicting catheter-related deep vein thrombosis (DVT) after an incident (ie, first) catheter-related DVT in children remains unclear. The present study investigated the association between thrombophilia and recurrent catheter-related DVT. Children with thrombophilia testing, performed according to the clinician's judgment and the family's preference, and a history of objectively confirmed catheter-related DVT were included in the study. Recurrent catheter-related DVT after placement of a new catheter was the main outcome. Thrombophilia was classified as minor, major, or none. Analysis was conducted using mixed effect logistic regression. A total of 245 patients had 1,365 catheters inserted; 941 of these catheters were placed after the incident catheter-related DVT. Anticoagulants as treatment or prophylaxis were administered in 78.1% of inserted catheters for at least 50% of the time they were in place. Minor thrombophilia was found in 12.7% of patients, whereas major thrombophilia was seen in 8.2% of children. The incidence rate of recurrent events was 0.23/100 catheter-days (95% confidence interval, 0.19-0.28 catheter-days); 34.3% (95% confidence interval, 28.6%-40.0%) of patients requiring a new catheter after their incident thrombotic event had at least 1 recurrent event. The incidence proportion of bleeding complications was 4.6/100 patients receiving anticoagulation. Young age of the patient at the time of catheter insertion and lack of administration of treatment or prophylactic doses of anticoagulant were predictive of recurrent events. In contrast, thrombophilia was not predictive of recurrent catheter-related DVT during subsequent catheter insertions among tested patients. Our findings suggest that thrombophilia testing to predict recurrence in these patients may be unnecessary.

Objective: Our goal was to conduct the generation and piloting of a discriminative and evaluative tool for pediatric post-thrombotic syndrome.Methods: We followed a formative model for the development of the tool, focusing on the signs/symptoms (items) that define post-thrombotic syndrome. For item generation, pediatric thrombosis experts and diagnosed with extremity post-thrombotic syndrome during childhood nominated items. In the piloting phase, items were cross-sectionally measured in children with limb deep vein thrombosis to examine the performance of the items.Result: Twenty-three experts and 16 subjects listed 34 items, which were then measured in 140 subjects with previous diagnosis of limb deep vein thrombosis (70 upper extremity and 70 lower extremity). The items with strongest correlation with post-thrombotic syndrome severity and largest area under the curve were pain (in older children), paresthesia, and swollen limb for the upper extremity group, and pain (in older children), tired limb, heaviness, tightness and paresthesia for the lower extremity group.Conclusion: Diagnostic properties and correlation with post-thrombotic syndrome severity of the different signs and symptoms varied according to the assessed venous territory.The information gathered in this study will help experts decide which item should be considered for inclusion in the new tool.