Pediatric thermal epiglottitis: insights from a tertiary center experience.

Thermal epiglottitis, a non-infectious cause of epiglottitis, is a rare entity that shares some clinical features with infectious epiglottitis. This study presents 16 years of experience in diagnosing and managing thermal epiglottitis. A retrospective descriptive study in a tertiary center in southern Israel included confirmed cases of thermal epiglottitis in children (0-18 years) between 2004 and 2020 by endoscopy. Of approximately 600,000 pediatric ER admissions between 2004 and 2020, seven children were diagnosed by endoscopy with thermal epiglottitis (mean age 24 months, 71% males). Clinical presentation included stridor, respiratory distress, and drooling. Four children had fever and elevated inflammatory markers at presentation and were treated with systemic antibiotics. All were treated with systemic steroids. The median length of stay in the PICU was five days, and four patients required intubations. All fully recovered without experiencing any sequelae.  Conclusion: Thermal epiglottitis stands as a potential contributor to acute upper airway obstruction. Although it's rarity, it should be discussed in any child with acute upper airway obstruction. It is essential to inquire directly about the accidental intake of hot beverages, particularly in cases lacking fever or elevated inflammatory markers. What is Known: • Thermal epiglottitis is a rare, non-infectious condition sharing clinical features with infectious epiglottitis. • Common presentations include stridor, respiratory distress, and drooling. What is New: • Thermal epiglottitis is a potential contributor to acute upper airway obstruction, urging consideration even in the absence of fever or elevated markers. • Direct inquiry about hot beverage intake for diagnosis is essential for diagnosis.

Neonatal diagnosis of primary ciliary dyskinesia in a high consanguinity population: a single tertiary center experience.

Though PCD usually presents after birth in term neonates, diagnosing PCD during the neonatal and infancy stages is uncommon, particularly in children who do not exhibit laterality defects. We report our recent experience with the diagnosis of PCD in the neonatal and early infantile period in a highly consanguine population. This was achieved by implementing a novel genetic-based diagnostic approach based on direct testing for recognized regional genetic variants. We conducted a retrospective analysis of children diagnosed with PCD at Soroka University Medical Center during the neonatal or early infantile period between 2020 and 2023. We included children under 3 months of age who had a genetic confirmation of PCD, as evidenced by the presence of two pathogenic variants in recognized genes. Genetic testing targeted regional genetic variants in previously identified PCD genes. Eight patients were included. The median age at diagnosis was 12.5 days. Three (38%) were born prematurely < 34 weeks gestational age. All patients were presented with respiratory distress and hypoxemia after birth. The median duration of oxygen support was 23 days, and upper lobe atelectasis was present in five patients (63%). Congenital cardiac malformation was present in four patients. Organ laterality defects were present in four patients. Genetic mutations identified were in the DNAAF5, DNAL1, DNAAF3, and DNAH1 genes.     Conclusion: Neonatal diagnosis of PCD is uncommon, especially in atypical presentations such as children without laterality defects or preterms. Focusing on a genetic diagnosis of the local tribal pathogenic variants promotes a potential cost-efficient test leading to earlier diagnosis. There is a need for a standardized protocol for earlier diagnosis of PCD in high-consanguinity areas. What is Known: • Primary ciliary dyskinesia (PCD) typically presents after birth in term neonates. • Diagnosing PCD during neonatal and infancy stages is challenging, particularly in children without laterality defects. What is New: • A novel genetic-based diagnostic approach was implemented on the neonatal population in a highly consanguine community, focusing on direct testing for regional genetic variants, leading to early and rapid diagnosis of PCD.

Stepwise genetic approach for the diagnosis of primary ciliary dyskinesia in highly consanguineous populations.

BACKGROUND: The American Thoracic Society guidelines for the diagnosis of primary ciliary dyskinesia (PCD) consider the presence of a bi-allelic pathogenic variant confirmatory for the diagnosis of PCD, with genetic testing recommended when other confirmatory diagnostic tests are less accessible. We present our experience with genetic testing as first line with a proposed algorithm for high consanguinity populations. METHODS: Patients with a suspected diagnosis of PCD underwent genetic testing according to a diagnostic algorithm composed of three steps: (1) patients with a previously known causative familial/Bedouin tribal pathogenic variant completed direct testing for a single variant; (2) if the initial test was negative or there was no known pathogenic variant, a PCD genetic panel was completed; (3) if the panel was negative, whole exome sequencing (WES) was completed. RESULTS: Since the implementation of the protocol, diagnosis was confirmed by genetic testing in 21 patients. The majority of them were of Bedouin origin (81%) and had a positive history of consanguinity (65%). Nine patients (43%) had a sibling with a confirmed diagnosis. Most patients (15/21, 71%) were diagnosed by direct pathogenic variant testing and the remainder by genetic panel (19%) and WES (10%). Disease-causing variants were found in nine genes, with DNAL1 (24%) and DNAAF3, DNAAF5, ZMYND10 (14% each) as the most prevalent ones. CONCLUSIONS: In highly consanguineous regions, a stepwise genetic testing approach is recommended. This approach may be particularly useful in areas where the ability to obtain confirmatory diagnostic tests through other modalities is less accessible.

Bronchodilator responsiveness in children with primary ciliary dyskinesia.

Background: Reversible airway obstruction is common in children with primary ciliary dyskinesia. However, the diagnostic value of adding bronchodilator (BD) response testing to routine spirometry is unclear. Methods: This is a retrospective analysis of pulmonary function test results obtained from children with primary ciliary dyskinesia seen as outpatients at the Hospital for Sick Children, Toronto. Spirometry results were collected for every appointment with BD response testing ("Visit", with pre-BD and post-BD measurements) as well as for the previous ("Baseline") and following ("Follow-up") encounters. Results: A positive BD response was seen in 86 out of 474 (18.1%) of the pulmonary function tests from 82 children with primary ciliary dyskinesia. BD responsiveness was associated with a significant absolute change (±sd) in % predicted forced expiratory volume in 1 s (FEV1) from Baseline to Visit pre-BD (-6.5±10.3%, p<0.001), but not from Baseline to Follow-up (0.4±10.8, p=0.757). Antimicrobial therapy was initiated more commonly following a Visit with a positive BD response (OR 3.8, 95% CI 2.2-6.6) compared to no BD response. Children with a positive BD response had a greater annual decline in FEV1 % predicted compared to those with no BD response (-0.9% per year versus -0.5% per year, p<0.001). The annual decline in FEV1 % predicted was greater in children with multiple compared to one measured positive BD responses (-1.3% per year versus -0.6% per year, p<0.001) and in those not treated with antibiotic therapy following a positive BD response compared to those treated with antibiotics (-1.1% versus -0.6%, p<0.001). Conclusion: A positive BD response in children with primary ciliary dyskinesia may help identify those at risk for accelerated lung disease progression.

Foreign body aspiration score (FOBAS)-a prospectively validated algorithm for the management and prediction of foreign body aspiration in children.

Foreign body aspiration (FBA) is a common cause of pediatric morbidity, but a standardized protocol to guide decision-making about bronchoscopy is lacking. We aimed to validate a new Foreign body aspiration score (FOBAS) for the pediatric emergency department (ED). Patients aged 0-18 years referred to the ED for suspected FBA were prospectively enrolled. FOBAS was calculated according to clinical features of a choking episode, sudden cough, exposure to nuts, absence of fever and rhinitis, stridor, and unilateral auscultatory and radiological findings. FBA risk was evaluated based on the total score (low, 1-3; moderate, 4-6; high, 7-10). Low-risk children were discharged from the ED and followed clinically. Moderate-risk children were hospitalized and evaluated by a pediatric pulmonologist, and high-risk children were referred directly for therapeutic bronchoscopy. Among the 100 enrolled children (59% males; median age 20 [interquartile range 11-39] months), a foreign body was diagnosed in 1/49 (2%), 14/41 (34.1%), and 9/10 (90%) with low, moderate, and high FOBAS, respectively (P < .001). Logistic regression indicated a higher risk for FBA with higher scores. The odds ratio for each additional point was 2.75 (95% confidence interval 1.78-4.24), and FOBAS showed a high predictive value for FBA (area under the curve 0.89). FOBAS implementation significantly reduced the rate of negative bronchoscopies, from 67.4% annually during 2016-2019 to 50% in 2020 (P = .042). CONCLUSION: FOBAS reliably predicts FBA in cases of suspected FBA and improves management and in-hospital decision-making. WHAT IS KNOWN: • Foreign body aspiration is a major cause of pediatric morbidity and mortality. • Currently, there is no unified protocol for children referred to the emergency department for suspected FBA, therefore, a well-defined algorithm is needed to improve the decision-making process. WHAT IS NEW: • The pediatric Foreign body aspiration score (FOBAS) is a new, prospectively validated clinical score that shows high sensitivity and specificity for the presence of FBA in children. • FOBAS reduces unnecessary admissions and invasive procedures and leads to better clinical outcomes.

Identification of obstructive sleep apnea in children with obesity: A cluster analysis approach.

BACKGROUND: Obstructive sleep apnea (OSA) is a heterogeneous disorder with a prevalence of 25%-60% in children with obesity. There is a lack of diagnostic tools to identify those at high risk for OSA. METHOD: Children with obesity, aged 8-19 years old, were enrolled into an ongoing multicenter, prospective cohort study related to OSA. We performed k-means cluster analysis to identify clinical variables which could help identify obesity related OSA. RESULTS: In this study, 118 participants were included in the analysis; 40.7% were diagnosed with OSA, 46.6% were female and the mean (SD) body mass index (BMI) and age were 39.7 (9.6) Kg/m², and 14.4 (2.6) years, respectively. The mean (SD) obstructive apnea-hypopnea index (OAHI) was 11.0 (21.1) events/h. We identified two distinct clusters based on three clustering variables (age, BMI z-score, and neck-height ratio [NHR]). The prevalence of OSA in clusters 1 and 2, were 22.4% and 58.3% (p = 0.001), respectively. Children in cluster 2, in comparison to cluster 1, had higher BMI z-score (4.7 (1.1) versus 3.2 (0.7), p < 0.001), higher NHR (0.3 (0.02) versus 0.2 (0.01), p < 0.001) and were older (15.0 (2.2) versus 13.7 (2.9) years, p = 0.09), respectively. However, there were no significant differences in sex and OSA symptoms between the clusters. The results from hierarchical clustering were similar to k-means analysis suggesting that the resulting OSA clusters were stable to different analysis approaches. INTERPRETATION: BMI, NHR, and age are easily obtained in a clinical setting and can be utilized to identify children at high risk for OSA.

Longitudinal Assessment of Curaçao Criteria in Children with Hereditary Hemorrhagic Telangiectasia.

OBJECTIVE: To assess the utility of the Curaçao criteria by age over time in children with hereditary hemorrhagic telangiectasia (HHT). STUDY DESIGN: This was a single-center, retrospective analysis of patients attending the HHT clinic at the Hospital for Sick Children (Toronto, Canada) between 2000 and 2019. The evaluation of the Curaçao criteria was completed during initial and follow-up visits. Screening for pulmonary and brain arteriovenous malformations was completed at 5 yearly intervals. RESULTS: A total of 116 patients with genetic confirmation of HHT were included in the analysis. At initial screening at a median (IQR) age of 8.4 (2.8, 12.9) years, 41% met criteria for a definite clinical diagnosis (≥3 criteria). In children <6 years at presentation, only 23% fulfilled at least 3 criteria initially. In longitudinal follow-up, 63% reached a definite clinical diagnosis, with a median (IQR) follow-up duration of 5.2 (3.2, 7.9) years (P = .005). Specifically, more patients met the epistaxis and telangiectasia criteria at last visit compared with initial (79% vs 60%; P = .006; 47% vs 30%; P = .02) but not for the arteriovenous malformation criterion (59% vs 57%; P = .65). CONCLUSIONS: In the pediatric population, most patients do not meet definite clinical criteria of HHT at initial presentation. Although the number of diagnostic criteria met increased over time, mainly due to new onset of epistaxis and telangiectasia, accuracy remained low during follow-up visits. Relying solely on clinical criteria may lead to underdiagnosis of HHT in children.

Treatment response to pulmonary exacerbation in primary ciliary dyskinesia.

INTRODUCTION: Pulmonary exacerbation (Pex) are common in pediatric primary ciliary dyskinesia (PCD), however changes in forced expiratory volume in 1 s precent predicted (FEV1pp) during Pex are not well described. AIM: To assess the evolution of FEV1pp during Pex and to define factors associated with failure to return to baseline lung function. METHOD: This was a retrospective study of patients with PCD between 2010 and 2022. Pex were defined as the presence of increased respiratory symptoms treated with intravenous (IV) antibiotics. The main outcomes were the changes in FEV1 during therapy and the proportion of patients (responders) achieving ≥90% of baseline FEV1pp values at the end of admission. RESULTS: The study included 52 Pex events in 28 children with PCD. The rate of responders was 32/41 (78%) at the end of admission. Nonresponse was associated with lower median body mass index (BMI) Z-score (-2.4 vs. -0.4, p < .01) and with a history of IV treated Pex in the previous year (p = .06). For the 22 Pex with available FEV1pp measurements at mid admission, the median relative and absolute improvement from admission to Day 7 was 9.1% and 6.2%, respectively (p- .001), and from Days 7 to 14 was 4.4% and 2.8%, respectively (p = .08). CONCLUSION: In children with PCD treated with IV antibiotics, the majority of lung function recovery happens during the first week of IV therapy. Lower BMI was associated with nonresponse to therapy.

Evaluation of Foreign body aspiration score (FOBAS) in children- A retrospective cohort study.

Foreign Body Aspiration (FBA) is a common medical emergency among young children, but the evaluation and management of a suspected FBA case can vary across physicians and centers. We aimed to identify which clinical, laboratory, and radiological findings can predict FBA in children and to evaluate a clinical score to improve FBA prediction. This is a retrospective cohort study of patients aged 0-18 years admitted to Soroka University Medical Center between 2010 and 2020 with suspected FBA. All patients underwent flexible bronchoscopy and were divided into positive and negative FBA groups. A newly developed foreign body aspiration score (FOBAS), based on medical history, physical examination, and chest X-ray findings, was evaluated for its predictability. The study included 412 children (median age 21 months, 56.8% females), of whom 154 (37.4%) had FBA and 258 (62.6%) did not. Multivariate regression analysis showed exposure to nuts/seeds, unilateral wheezing or decreased breath sounds, stridor, and suggestive findings on chest X-ray were significant risk factors for FBA (OR [95%CI] -1.994[1.290-3.082], 1.487[1.206-1.832], 1.883 [1.011-3.509] and 2.386[1.917-2.970], respectively). However, a choking episode, acute cough, and absence of fever and rhinorrhea did not predict FBA. FOBAS showed an increased risk of FBA for each additional point of the score, with an odds ratio of 1.572 (95% CI-1.389-1.799).  Conclusion: FOBAS is a good predictor for the presence of FBA in children. Once prospectively validated, FOBAS could aid in decision-making at the emergency department, enabling more standardized care, reducing unnecessary procedures, and leading to better clinical outcomes. What is Known: • The evaluation and management of a child with suspected foreign body aspiration (FBA) vary across physicians and centers, without a consensus regarding the indications and criteria for performing bronchoscopy. • Flexible bronchoscopy is the standard procedure for the diagnosis and sometimes treatment of FBA in children, but it may hold potential complications. What is New: • We propose a newly developed foreign body aspiration score (FOBAS), based on medical history, physical examination, and chest X-ray findings, for the prediction of FBA in children at the emergency department. • The FOBAS is a good predictor of FBA in children. The score enables more standardized care and may reduce unnecessary procedures.

Prevention and Treatment Strategies for Respiratory Syncytial Virus (RSV).

Respiratory syncytial virus (RSV) is a leading cause of severe lower respiratory tract disease, especially in young children. Despite its global impact on healthcare, related to its high prevalence and its association with significant morbidity, the current therapy is still mostly supportive. Moreover, while more than 50 years have passed since the first trial of an RSV vaccine (which unfortunately caused enhanced RSV disease), no vaccine has been approved for RSV prevention. In the last two decades, our understanding of the pathogenesis and immunopathology of RSV have continued to evolve, leading to significant advancements in RSV prevention strategies. These include both the development of new potential vaccines and the successful implementation of passive immunization, which, together, will provide coverage from infancy to old age. In this review, we provide an update of the current treatment options for acute disease (RSV-specific and -non-specific) and different therapeutic approaches focusing on RSV prevention.

The long-term outcomes of symptomatic congenital lobar emphysema patients.

INTRODUCTION: Surgical (OP) management for symptomatic congenital lobar emphysema (CLE) is the standard of care with nonoperative (NOP) approach applied for asymptomatic cases. The aim of this study is to report the outcomes for NOP approach to the care of symptomatic CLE infants. METHODS: A retrospective study of CLE patients treated 2000-2021 at a single institution. Patients with CLE and respiratory symptoms were included. RESULTS: Overall, 23 children had symptomatic CLE, and 12 had NOP management. The median age at diagnosis was 38.5 days (50) in the NOP group versus 25 days (20) in the OP group (p = 0.31). There was no significant difference in the location of the involved lobe, term birth, postnatal diagnosis and gender, and both groups required noninvasive support in 33% of the cases. There was a trend towards higher frequency of oxygen support in the OP group preoperatively (89% vs. 42%, p = 0.07). The median length of stay was 14 days in the NOP group compared to a median postsurgery stay of 7.5 days in the OP group. In follow-up, there was no significant difference in respiratory readmission in first year of life, growth delay, treatment with asthma medication or body mass index in the NOP versus OP group. None of the children in the NOP group required surgery during follow-up. CONCLUSIONS: A NOP approach for symptomatic CLE infants can have favorable long-term outcomes. Further studies will be required to identify markers to aid in clinical decision-making.

Efficacy of Antibiotic Eradication Therapy of Early Pseudomonas aeruginosa Infection in Children with Primary Ciliary Dyskinesia.

Rationale: Chronic infection with Pseudomonas aeruginosa (PsA) negatively impacts lung disease in patients with primary ciliary dyskinesia (PCD). There is currently limited evidence regarding the efficacy of PsA antibiotic eradication therapy (AET) in children with PCD. Objectives: To assess the effectiveness of AET of early PsA infection in children with PCD. Methods: This retrospective study included pediatric patients with a confirmed PCD diagnosis according to the American Thoracic Society guidelines at the Hospital for Sick Children between 2010 and 2022. Children with newly acquired PsA infection underwent AET using a stepwise protocol. The protocol included the following steps: step 1, 28 days of tobramycin inhalation solution (TIS); step 2, repeat TIS if culture positive after step 1; and step 3, 14 days of intravenous antibiotics followed by 28 days of TIS if culture positive after step 2. Step 3 was also used for patients who presented with pulmonary exacerbation symptoms. The main outcome was a PsA-negative culture result based on the microbiological results of the first culture after completion of each step of treatment. Results: During the study period, 31 children had a new PsA infection and underwent AET. Of the 27 children who had been asymptomatic at the time of the PsA infection, negative PsA culture results were achieved in 20 (74%) of 27, 1 (14%) of 7, and 5 (83%) of 6 after steps 1, 2, and 3 of AET, respectively. All four symptomatic patients who initially were treated with step 3 had successful clearance of PsA. The overall cumulative success rate of the protocol for negative culture results after AET was 97% (30 of 31). For patients in whom AET was successful, the probability of staying PsA free for at least 1 year was 70%. Conclusions: AET for early PsA infection is highly effective in PCD, with sustained efficacy in most individuals. These data suggest that AET should be considered in all children with PCD who have early PsA infection.

Foreign body aspiration in Israeli children during the COVID-19 pandemic.

BACKGROUND: Since the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, there has been a decline in pediatric emergency department visits. Our aim was to assess the pattern of pediatric foreign body aspiration (FBA) during the first year of the COVID-19 pandemic, in comparison to the prior years. METHODS: In this retrospective multicenter study, we compared the number of children who presented with FBA during the COVID-19 year (March 1, 2020 to February 28, 2021) to the annual average of the years 2016-2019. We also compared the lockdown periods to the postlockdown periods, and the percentage of missed FBA, proven FBA, and flexible bronchoscopy as the removal procedure. RESULTS: A total of 345 children with FBA from six centers were included, 276 in the pre-COVID-19 years (average 69 per year) and 69 in the COVID-19 year. There was no difference in the prevalence of FBA between the COVID-19 year and any of the prior 4 years. Examining the lockdown effect, the monthly incidence of FBA dropped from a pre-COVID-19 average of 5.75 cases to 5.1 cases during lockdown periods and increased to 6.3 cases in postlockdown periods. No difference in the percentage of missed FB or proven FB was observed. There was a significant rise in the usage of flexible bronchoscopy as the removal procedure (average of 15.4% vs. 30.4%, p = 0.001). CONCLUSION: There were fewer cases of pediatric FBA during lockdown periods, compared to post-lockdown periods, presumably related to better parental supervision, with no difference in the prevalence of FBA during the COVID-19 year.

Echis coloratus envenomation in children: a retrospective case series.

BACKGROUND: Antivenom has been used successfully to treat systemic and progressive, local manifestations of envenomations inflicted by Echis coloratus, the second most common cause of snake envenomation in Israel. There is a paucity of published data regarding the use of monovalent (equine) immunoglobulin G antivenom in children. This study describes outcomes from the regimen used in two large, tertiary care pediatric centers. METHODS: A retrospective chart review of children admitted with definite or probable signs of Echis coloratus envenomation to Sourasky (Tel Aviv) and Soroka (Be'er Sheva) Medical Centers from January 1st 2008-to June 1st 2019. Extracted data included age, location of bite, time to hospital arrival, laboratory test results, complications, time to antivenom administration if indicated, adverse effects of the antivenom, and outcomes. Indications for antivenom were: diagnosis of Echis coloratus as the etiology of envenomation, local and systemic signs e.g. skin puncture wounds, swelling of the involved limb, local hematoma, and abnormal coagulation blood test results. RESULTS: During the study period, 11 children were treated with intravenous Echis coloratus antivenom. Median age was 9 years and 10 of 11 patients were male. Two patients underwent fasciotomy; in one, compartment syndrome was diagnosed by pressure measurement, and in the second, clinically. One patient developed mild urticaria 30 min after initiation of the antivenom; the treatment was stopped and then restarted at a slower rate after he was treated with hydrocortisone and diphenhydramine. No further adverse reactions were observed. CONCLUSIONS: In children, Echis coloratus antivenom appeared to be effective and safe for the treatment of systemic and progressive local manifestations of envenomation by Echis coloratus.

Non-tuberculous mycobacteria infection treated with intermittently inhaled high-dose nitric oxide.

Mycobacterium abscessus is an emerging multidrug-resistant non-tuberculous mycobacterium (NTM) with high prevalence in patients with cystic fibrosis. However, studies on antimicrobial susceptibilities and effective treatments against M. abscessus are still limited. Nitric oxide (NO) is important in innate immune response to various infections, including mycobacterial infections. In this case study, we describe a compassionate treatment of inhaled NO (iNO) at 150-250 ppm for 4 weeks. The dosing strategy proposed for this treatment was selected to minimise the potential of adverse events, while maximising the antibacterial effectiveness of NO, and was found to be safe, well tolerated and resulted in positive clinical findings including improvement in patient well-being, CT scan values, quality of life and bacterial load. Taken together, these observations may indicate that iNO could play a crucial role and potentially serve as a reliable option in the treatment of patients with chronic refractory NTM lung infection.

Comparison of septic and nonseptic pulmonary embolism in children.

BACKGROUND: Septic pulmonary embolism (SPE) in children is a rare disease. Data are scarce regarding the clinical and laboratory manifestation of SPE compared with nonseptic pulmonary embolism (ns-PE). Furthermore, specific guidelines for the management of SPE in children are lacking. AIM: We compared the clinical course and outcome of children with SPE and ns-PE. METHODS: A retrospective, cohort study of hospitalized children, 2005-2020, with documented pulmonary embolism imaging. RESULTS: Sixteen children (eight SPE, eight ns-PE) were identified. Episodes of SPE occurred secondary to endocarditis, musculoskeletal and soft tissue infections, with Staphylococcus aureus (n = 4) and streptococcus spp. (n = 2) as the most common pathogens. Radiographically, SPE presented as a microvascular disease with parenchymatic nodules/cavitations, whereas ns-PE presented as larger vessel disease with filling defects. Risk factors (including thrombophilia) were noted in 0% and 87.5% of SPE and ns-PE patients, respectively (p < .01). Pulmonary embolism diagnosis was delayed in SPE compared with ns-PE (median: 8.5 days vs. 1 day). The SPE group had higher rates of fever (100% vs. 12.5%, p < .01), C-reactive protein (CRP levels; 18.49 vs. 4.37 mg/dl, p = .02), and fibrinogen levels (880 vs. 467 mg/dl, p < .001). Antithrombotic treatment for >4 months was administrated to 14.3% and 87.5% of SPE and ns-PE patients, respectively (p < .01). One ns-PE patient had a second thromboembolic event compared to none in the SPE group. CONCLUSIONS: SPE in children is a unique subgroup of PE with different clinical and laboratory findings that requires a different diagnostic approach and probably shorter duration of antithrombotic treatment.