Ligamentous laxity in children with achondroplasia: Prevalence, joint involvement, and implications for early intervention strategies.

Achondroplasia (ACH), the most common form of skeletal dysplasia, is characterized by severe disproportionate short stature, rhizomelia, exaggerated lumbar lordosis, brachydactyly, macrocephaly with frontal bossing and midface hypoplasia. Ligamentous laxity has been reported as a striking feature of ACH, but its prevalence and characteristics have not been systematically evaluated yet. There is growing evidence that ligamentous laxity can be associated with chronic musculoskeletal problems and may affect motor development leading to abnormal developmental trajectories. This study aimed to assess the prevalence of ligamentous laxity in children with ACH through standardized tools, the Beighton scale and its modified version for preschool-age children. A total of 33 children (mean age 6.4 ± 3.2 years; age range 1-12.5 years) diagnosed with ACH by the demonstration of a pathogenic variant in the FGFR3 gene and 33 age- and sex-matched healthy controls were included in the study. Both ligamentous laxity assessment and neurological examinations were performed; medical history was also collected from caregivers. Children with ACH showed a 2 times higher risk of ligamentous laxity than the group without skeletal dysplasia (OR = 2.2; 95% CI = 1.0 to 4.7), with 55% of children meeting the diagnostic criteria for hypermobility. No significant difference in ligamentous laxity was observed between males and females. Joint involvement analysis revealed characteristic patterns, with knee hypermobility observed in 67% of patients, while rare was elbow hypermobility. Longitudinal assessments indicated a decreasing trend in ligamentous laxity scores over time, suggesting a potential decrease in hypermobility issues during adulthood. The findings of this study provide valuable insights into the prevalence and characteristics of ligamentous laxity in ACH. Implementation of standardized ligamentous laxity assessments might guide patients' follow-up and facilitate early interventions, helping to prevent pain and improve outcomes and quality of life for such patients. Further prospective studies are needed to explore the natural history of ligamentous laxity in ACH and investigate the potential impact of emerging pharmacological treatments upon hypermobility.

Utility of Rapid Nasopharyngeal Swab for Respiratory Pathogens in the Diagnosis of Viral Infections in Children Hospitalized with Fever: A Prospective Validation Study to Improve Antibiotic Use.

Introduction: Fever is among the most common reason for medical assessment and antibiotic prescription in practice. The aim of this study was to evaluate positive and negative predictive values of rapid nasopharyngeal swabs for respiratory pathogens to discriminate viral from bacterial infections. Methods: We prospectively tested children with signs and/or symptoms of infections (e.g., fever, cough, wheezing, suspected urinary tract infection) admitted to a paediatric department. Following discharge, clinical phenotypes were assigned defining a cohort of children having probable/certain viral infection, probable/certain bacterial infection, other inflammatory conditions or healthy controls. Results: In this study, 190 children were enrolled (50.5% females, median age 30.5 (8-86) months). In total, 102 patients (53.7%) were affected by respiratory viral infections, 16 (8.4%) by bacterial infections, 29 (15.3%) were healthy controls and 43 (22.6%) were affected by another pathological condition manifested with fever. In total, 84.3% of patients classified as viral infection tested positive for viruses, compared with 18.8% of patients with bacterial infection (p < 0.001), 18.6% of patients with other condition (p < 0.001) and 17.2% of control patients (p < 0.001). The positive predictive value of NPSs in the diagnosis of viral infection was 88.6% and the negative predictive value was 75.0%. Conclusion: Our findings suggest that rapid NPS tests for respiratory viruses are a useful tool to confirm viral infections in children with fever and improve antibiotic use.

Persisting Gastrointestinal Symptoms in Children with SARS-CoV-2: Temporal Evolution over 18 Months and Possible Role of Lactoferrin.

BACKGROUND AND AIM: Persisting gastrointestinal symptoms are reported to be relatively common in children with long COVID; however, their detailed characterization and long-term outcomes have not yet been described. METHODS: We performed a retrospective study aiming to investigate the temporal evolution of gastrointestinal symptoms in children with SARS-CoV-2, from acute infection to 18-months follow-up. To further investigate possible therapeutic strategies, we evaluated the role of lactoferrin in improving gastrointestinal symptoms in these children, compared with those not treated. RESULTS: A total of 1224 patients (47.7% females) were included. Of these participants, 246 (19.8%) were vaccinated and 143 (11.5%) presented with comorbidities. A total of 175 patients (14.1%) presented gastrointestinal symptoms during acute infection, 54 (4.4%) at three months, 23 (1.9%) at six months, 6 (3.3%) at twelve months, and 2 (2.3%) at eighteen months follow-up. At six months follow-up, children who were treated with 3 months oral lactoferrin had less persisting symptoms compared to those who did not receive lactoferrin, although this difference was not statistically significant (three patients (25%) in the lactoferrin group vs. fourteen patients (33.3%) not treated, p = 0.73), probably due to the low number of patients with persisting GI symptoms. CONCLUSIONS: GI symptoms are relatively common during acute SARS-CoV-2 infection in children, and a non-negligible proportion of these children reported persisting symptoms for up to 12-18 months after the acute infection. In addition, we found a trend even if statistically nonsignificant toward faster improvement of persisting gastrointestinal symptoms in children with long COVID treated with lactoferrin. Despite the limitations relating to the present study's design, given the significant burden of gastrointestinal symptoms in children with long COVID, our findings provide the basis to perform a prospective, placebo-controlled study.

Validation and cross-cultural adaptation of the Italian version of the paediatric eating assessment tool (I-PEDI-EAT-10) in genetic syndromes.

BACKGROUND: The Pediatric Eating Assessment Tool (PEDI-EAT-10) is a reliable and valid tool for rapid identification of dysphagia in patients aged 18 months to 18 years. AIMS: To translate and adapt the PEDI-EAT-10 into the Italian language and evaluate its validity and reliability. METHODS & PROCEDURES: The translation and cross-cultural adaptation of the tool consisted of five stages: initial translation, synthesis of the translations, back translation, expert committee evaluation and test of the prefinal version. The internal consistency of the translated tool was analysed in a clinical group composed of 200 patients with special healthcare needs aged between 18 months and 18 years. They were consecutively enrolled at the Rare Disease Unit, Paediatrics Department, Fondazione Policlinico Agostino Gemelli-IRCCS, Rome. For test-retest reliability, 50 caregivers filled in the PEDI-EAT-10 questionnaire for a second time after a 2-week period. Construct validity was established by comparing data obtained from patients with data from healthy participants (n = 200). The study was approved by the local ethics committee. OUTCOMES & RESULTS: Psychometric data obtained from patients (104 M; mean age = 8.08 ± 4.85 years; median age = 7 years) showed satisfactory internal consistency (Cronbach's α = 0.89) and test-retest reliability (Pearson r = 0.99; Spearman r = 0.96). A total of 30% of children were classified as having a high risk of penetration/aspiration. The Italian PEDI-EAT-10 mean total score of the clinical group was significantly different from that resulting from healthy participants. CONCLUSIONS & IMPLICATIONS: The PEDI-EAT-10 was successfully translated into Italian, validated and found to be a reliable one-page rapid screening tool to identify dysphagia in children and adolescents with special needs. WHAT THIS PAPER ADDS: What is already known on the subject The PEDI-EAT-10 is a valid and reliable quick discriminative paediatric tool for identifying penetration/aspiration risks. What this paper adds to the existing knowledge In the present study we successfully translated and adapted the PEDI-EAT-10 into the Italian language. What are the potential or actual clinical implications of this work? This translation and adaptation increase access to valid feeding and swallowing assessment for children of Italian-speaking families. In addition, the I-PEDI-EAT-10 can suggest further assessment of patients' swallowing abilities.

Persistent respiratory symptoms associated with post-Covid condition (Long Covid) in children: a systematic review and analysis of current gaps and future perspectives.

INTRODUCTION: There is increasing evidence that also children can develop Long Covid. However, there are no specific reviews providing a clear description of reported respiratory symptoms and potential diagnostics. AREAS COVERED: We performed on PubMed a systematic search of studies conducted on children aged less than 18 years with previous SARS-CoV-2 infection complaining about persistent respiratory symptoms; the aim of our review is to characterize the incidence, pattern and duration of respiratory symptoms after the acute infection in pediatric population. EXPERT OPINION: Children can develop persisting respiratory symptoms, as documented by several follow-up studies both including or not control groups of non-infected children. However, the methodological variabilities of the analyzed studies does not allow to provide firm conclusions about the rate, type and best diagnostics for children with persistent respiratory symptoms. Future studies should investigate on larger pediatric cohorts the role of noninvasive diagnostics and new biomarkers as well as investigating therapeutic options both during acute infection or when Long Covid has been diagnosed.

How pain affect real life of children and adults with achondroplasia: A systematic review.

The clinical features of achondroplasia can cause acute self-limited pain that can evolve into chronic pain. Pain causes a low quality of life, in terms of physical, emotional, social, and school functioning in both adult and children with achondroplasia. We conducted a systematic review according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement to describe prevalence, assessment tools, causes and management strategies of pain in this rare disease. We found that shoulder and knee pain is typically referred during infancy, while knee pain is generally referred around 5-6 years of age. The prevalence of general pain in adolescence can be as high as 90%. Chronic pain in the achondroplasia population increases with age, with up to 70% of adults reporting general pain and back pain. Recognizing the multiple determinants of acute and chronic pain in patients with achondroplasia may enable physicians to better understand and manage this burden, particularly with the advent of new drugs that may modify some of the striking features of achondroplasia.

Social Stigma in Children with Long COVID.

There is growing evidence that adults with Long COVID suffer from different sets of stigmata related to their condition. In children with Long COVID, this aspect has never been investigated. This study aims to investigate if children with Long COVID also experience stigma. METHODS: Children with a previous SARS-CoV-2 infection evaluated at 3 month follow-ups in a pediatric post COVID unit were asked to fill in an online Long COVID Stigma Scale survey before they were assessed by a pediatrician. Doctors were unaware of children's responses when they performed a diagnosis of Long COVID or full recovery from previous infection, according to the World Health Organization definition of pediatric Long COVID. Responses to the Stigma scale were then compared in the two cohorts of children. RESULTS: 224 patients responded to the questionnaire; 40 patients were diagnosed with Long COVID. Children with Long COVID significantly more frequently felt embarrassed about having Long COVID (p 0.035), felt embarrassed about having physical limitations (p < 0.001), felt they were valued less due to Long COVID (p 0.003), felt they were different from other peers due to Long COVID (p 0.033), felt significantly more frequently that people behaved differently towards them because they might be lying since the diagnosis of Long COVID (p 0.006), that they were less respected by others due to Long COVID (p 0.017), that other people thought that Long COVID is not a real disease (p 0.007), that other people thought that developing Long COVID is a sign of weakness (p 0.008), and that other people might judge them negatively due to their diagnosis of Long COVID (p < 0.001). CONCLUSIONS: Children with Long COVID, similar to adults, are suffering from stigmata due to their condition,. These data may have implication and should be used by the public, policy makers, and healthcare professionals regarding pediatric Long COVID.

The "FEEDS (FEeding Eating Deglutition Skills)" over Time Study in Cardiofaciocutaneous Syndrome.

Feeding, eating and deglutition difficulties are key concerns in patients with cardiofaciocutaneous syndrome (CFCS). This study intends to quantify the development of feeding skills from birth to adulthood in patients with CFCS. Twenty-seven patients (eight males; mean age: 16.7 ± 8.3 years; median age: 15 years, age range: 1.5-38 years) with molecularly confirmed clinical diagnosis of CFCS were prospectively recruited from the Rare Disease Unit, Paediatrics Department, Fondazione Policlinico Agostino Gemelli-IRCCS, Rome, Italy, over a one-year period. Pathogenic variants along with key information regarding oro-motor features were collected. Sialorrhea was quantified using the Drooling Quotient 5. Feeding abilities were screened using the Italian version of the Montreal Children's Hospital Feeding Scale (I-MCH-FS). The oral sensory processing section of the Sensory Profile completed the assessment. Mild-to-profuse drooling was experienced by 25% of patients, and food taste selectivity was a constant during infancy (65%), with persistence even beyond adolescence. Nineteen percent of participants with long-term enteral feeding dependency had BRAF, KRAS and MAP2K1 mutations. These findings document that mealtime challenges in CFCS do not remain restricted only to the paediatric age, and that supportive care until adulthood plays a key role.

Role of Lung Ultrasound in the Follow-Up of Children with Previous SARS-CoV-2 Infection: A Case-Control Assessment of Children with Long COVID or Fully Recovered.

Lung ultrasound (LUS) can detect lower respiratory tract involvement in children with acute SARS-CoV-2 infection. However, its role in follow-up assessments is still unclear. To describe LUS findings in children after SARS-CoV-2 infection, we conducted a prospective study in a population of pediatric patients referred to the post-COVID unit in a tertiary center during the study period from February 2021 to May 2022. Children were classified as recovered from acute infection or with persisting symptoms. LUS was performed in all children and a LUS score (ranging from 0 to 36 points) was calculated according to the Italian Academy of Thoracic Ultrasound. Six hundred forty-seven children (304 females, 47%) were enrolled. The median follow-up evaluation was two months. The median age was 7.9 (IQR: 6) years. At the follow-up evaluation, 251 patients (38.8%) had persistent symptoms, of whom 104 (16.1%) had at least one respiratory symptom. The median LUS level was 2 (IQR: 4). LUS findings and LUS scores did not differ in children with Long COVID compared to the group of children fully recovered from the initial infection. In conclusion, after SARS-CoV-2 infection, LUS was mostly normal or showed minimal artifacts in all groups of children.

Lung perfusion assessment in children with long-COVID: A pilot study.

BACKGROUND: There is increasing evidence that chronic endotheliopathy can play a role in patients with Post-Covid Condition (PCC, or Long Covid) by affecting peripheral vascularization. This pilot study aimed at assessing lung perfusion in children with Long-COVID with 99m Tc-MAA SPECT/CT. MATERIALS AND METHODS: lung 99m Tc-MAA SPECT/CT was performed in children with Long-COVID and a pathological cardiopulmonary exercise testing (CPET). Intravenous injections were performed on patients in the supine position immediately before the planar scan according to the EANM guidelines for lung scintigraphy in children, followed by lung SPECT/CT acquisition. Reconstructed studies were visually analyzed. RESULTS: Clinical and biochemical data were collected during acute infection and follow-up in 14 children (6 females, mean age: 12.6 years) fulfilling Long-COVID diagnostic criteria and complaining of chronic fatigue and postexertional malaise after mild efforts, documented by CPET. Imaging results were compared with clinical scenarios during acute infection and follow-up. Six out of 14 (42.8%) children showed perfusion defects on 99m Tc-MAA SPECT/CT scan, without morphological alterations on coregistered CT. CONCLUSIONS: This pilot investigation confirmed previous data suggesting that a small subgroup of children can develop lung perfusion defects after severe acute respiratory syndrome coronavirus 2 infection. Larger cohort studies are needed to confirm these preliminary results, providing also a better understanding of which children may deserve this test and how to manage those with lung perfusion defects.

Risk factors for post-COVID-19 condition (Long Covid) in children: a prospective cohort study.

Background: Adults and children can develop post-Covid-19 condition (PCC) (also referred to as Long Covid). However, existing evidence is scarce, partly due to a lack of a standardised case definition, short follow up duration, and heterogenous study designs, resulting in wide variation of reported outcomes. The primary aim of this study was to characterise risk factors for PCC and longitudinal rates of recovery in a cohort of children and young people using a standardised protocol. Methods: We performed a prospective "disease-based" cohort study between 01/02/2020 to 31/10/2022 including children aged 0-18 years old, with a previous diagnosis of Covid-19. Children with microbiologically confirmed SARS-CoV-2 infection, were invited for an in-clinic follow-up assessment at a paediatric post-covid clinic in Rome, Italy, at serial intervals (3-, 6-, 12- and 18-months post-onset). PCC was defined as persistence of otherwise unexplained symptoms for at least three months after initial infection. The statistical association between categorical variables was obtained by Chi-squared tests or Fisher's exact tests. Multivariable logistic regressions are presented using odds ratios (OR) and 95% confidence interval (CI). Survival analysis was conducted using the Kaplan-Meier method. Findings: 1243 children were included, median age: 7.5 (4-10.3) years old; 575 (46.3%) were females. Of these, 23% (294/1243) were diagnosed with PCC at three months post-onset. Among the study population, 143 patients remained symptomatic at six months, 38 at 12 months, and 15 at 18 months follow up evaluation. The following risk factors were associated with PCC: >10 years of age (OR 1.23; 95% CI 1.18-1.28), comorbidities (OR 1.68; 95% CI 1.14-2.50), and hospitalisation during the acute phase (OR 4.80; 95%CI 1.91-12.1). Using multivariable logistic regression, compared to the Omicron variant, all other variants were significantly associated with PCC at 3 and 6 months. At least one dose of vaccine was associated with a reduced, but not statistically significant risk of developing PCC. Interpretation: In our study, acute-phase hospitalisation, pre-existing comorbidity, being infected with pre-Omicron variants and older age were associated with a higher risk of developing PCC. Most children recovered over time, but one-in-twenty of those with PCC at three months reported persistent symptoms 18 months post-Sars-CoV-2 infection. Omicron infection was associated with shorter recovery times. We did not find a strong protective effect of vaccination on PCC development. Although our cohort cannot be translated to all Italian children with PCC as more nationwide studies are needed, our findings highlight the need of new strategies to prevent and treat pediatric PCC are needed. Funding: This study has been funded by Pfizer non-competitive grant, granted to DB (# 65925795).

Risk Factors for Persistent Anosmia and Dysgeusia in Children with SARS-CoV-2 Infection: A Retrospective Study.

BACKGROUND: Olfactory and gustative dysfunctions are two of the most common post-acute sequelae of SARS-CoV-2 infection in children, which can have a negative impact on the routines of children and families. As several children have had COVID-19 since the Omicron variant, it is important to investigate if this increase in infections is reflected in higher olfactory/taste disfunctions. The primary aim of this study was to characterize the presence of olfactory/gustative problems in a cohort of children, its evolution, and its association with risk factors such as COVID-19 variant, hospitalization, presence of olfactory/gustative dysfunction during the acute phase, and vaccination. METHODS: This was a retrospective analysis of children with microbiologically confirmed SARS-CoV-2 infection evaluated in person at a referral pediatric post-COVID-19 clinic in Rome, Italy. We included children younger than 19 years old, evaluated from the beginning of the pandemic up to October 2022. At specific timepoints, we investigated the presence of olfactory/taste disfunctions and evaluated them according to the SARS-CoV-2 variants circulating at the time of infection. RESULTS: A total of 1250 children (650 females; 52.0%) with a mean age of 6.77 (±4.12) years were included in the study. At 3, 6, 12, and 18 months, 12 (9.6%), 7 (5.6%), 2 (1.6%), and 1 (0.8%) of the children reported anosmia and dysgeusia post-COVID-19 infection, respectively. The presence of anosmia and dysgeusia during the acute phase of infection and being infected with a pre-Omicron variant were found to be significant risk factors for persistent olfactory and gustatory dysfunction during all follow-up periods. CONCLUSIONS: anosmia and dysgeusia symptoms tended to decrease gradually over time, but not all children recovered quickly.

Ultrasound Imaging for Diaphragm Function in a Population of Healthy Infants: A Short Observational Report.

INTRODUCTION: Diaphragm ultrasound is increasingly used in adults, and more recently in pediatric practice. However, normal diaphragm parameters in healthy infants are unknown. This was a prospective observational pilot study aiming to define the normal diaphragm ultrasound characteristics in healthy infants during the first 6 months of life. METHODS: We recruited healthy neonates at 7 to 15 days of life, who were followed until the sixth month of life, undergoing five assessments in different time points. The measurements included diaphragm thickness at end expiration (TEE) and at end inspiration (TEI). The thickening fraction (TF) was calculated as (TEI-TEE)/TEE and expressed as a percentage, and as (TEI-TEE)/TEI. RESULTS: A total of 37 toddlers, 16 of which were females (43.2%), were enrolled. Thirty-four children (91.9%) were of Caucasian ethnicity and the median gestational age was 38.4 (35.7-40) weeks. Normal TEE, TEI, and TF have been provided for each time point. CONCLUSION: We provided new insight regarding data about thickness and thickening function in healthy children to be used for future physiologic and pathologic pediatric studies.

What to Expect of Feeding Abilities and Nutritional Aspects in Achondroplasia Patients: A Narrative Review.

Achondroplasia is an autosomal dominant genetic disease representing the most common form of human skeletal dysplasia: almost all individuals with achondroplasia have identifiable mutations in the fibroblast growth factor receptor type 3 (FGFR3) gene. The cardinal features of this condition and its inheritance have been well-established, but the occurrence of feeding and nutritional complications has received little prominence. In infancy, the presence of floppiness and neurological injury due to foramen magnum stenosis may impair the feeding function of a newborn with achondroplasia. Along with growth, the optimal development of feeding skills may be affected by variable interactions between midface hypoplasia, sleep apnea disturbance, and structural anomalies. Anterior open bite, prognathic mandible, retrognathic maxilla, and relative macroglossia may adversely impact masticatory and respiratory functions. Independence during mealtimes in achondroplasia is usually achieved later than peers. Early supervision of nutritional intake should proceed into adolescence and adulthood because of the increased risk of obesity and respiratory problems and their resulting sequelae. Due to the multisystem involvement, oral motor dysfunction, nutrition, and gastrointestinal issues require special attention and personalized management to facilitate optimal outcomes, especially because of the novel therapeutic options in achondroplasia, which could alter the progression of this rare disease.

Prognostic Value of the Area of Lung Involved in Severe and Non-Severe Bronchiolitis: An Observational, Ultrasound-Based Study.

BACKGROUND: Point of care lung ultrasound (LUS) has a definite role in viral bronchiolitis when combined with clinical data. Previous data showed a bigger involvement of the superior lung zones in more severe cases. The aim of the present study is to describe whether different lung areas are implicated to different degrees in patients admitted to a Pediatric Intensive Care Unit (PICU) and needing ventilation compared to those with less severe forms. METHODS: observational, prospective study. LUS scores of single lung areas and clinical data were collected for all children aged 0-12 months presenting with bronchiolitis to the participating centers and used as covariates for logistic regression having "PICU admission" as outcome. A subsequent analysis was carried out to investigate factors concurring with different lung zones' involvement. RESULTS: 173 patients were enrolled. Difficulty in feeding, presence of wheezing, SpO2 were all risk factors for PICU admission. Superior lung areas' LUS scores presented higher Odds Ratios for PICU admission and need for ventilation than inferior ones. Age and prematurity concurred in determining their higher LUS scores. CONCLUSIONS: Superior lobes' greater involvement could be favored by the geometrical distribution of relative bronchi, exiting with an acute angle from mainstem bronchi in small children where airway caliber is small and only small volumes of secretions can be occlusive.

Extended coagulation profile of children with Long Covid: a prospective study.

Emerging data suggests that endotheliopathy changes can be associated with post covid condition (PCC) in adults. Research on the matter in children is lacking. We analyzed an extended coagulation profile including biomarkers of endothelial damage in children with PCC and compared it with a control group of children that fully recovered post- SARS-CoV-2 infection. A case-control study enrolling children below 18 years of age with previous microbiologically confirmed SARS-CoV-2 infection in a pediatric post-covid unit in Italy ≥ 8 weeks after the initial infection. Samples were taken at 8 and 12 weeks after the SARS-CoV-2 diagnosis and analyzed for coagulation profiling (fibrinogen, prothrombin time, international normalized ratio, activated partial thromboplastin time, d-dimers, factor VIII coagulant activity, plasma von Willebrand factor (VWF) antigen and VWF ristocetin cofactor (RC)). We compared coagulation profiles in samples from children identified with PCC (at least one, or three or more symptoms, which could not be explained by an alternative diagnosis, at the 8- and 12-week follow-up assessment using the pediatric Long Covid International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) survey. Seventy-five children were enrolled, 49.3% were females, the median age was 10.2 (IQR 4.9) years. Forty-six (61%) of the children had at least one persisting symptom at the eight weeks post-onset, (PCC8); 39/75 (52%) had persistent symptoms for more than 12 weeks (PCC12) and 15/75(32%) had at least three persisting symptoms (PCC ≥ 3) at 12 weeks. Children with PCC presented more frequently with abnormal D-Dimer levels above the reference range compared to children that had fully recovered at the 8-12 weeks (39.1% vs. 17.2%, p = 0.04), and 12 week follow up or more (41% vs. 17.2%, p = 0.05), and in children with three or more symptoms at 12 weeks follow up compared to those that had recovered (64.3% vs. 22.2%, p = 0.002). For the other coagulation profiles, there were abnormal values detected for VWF, FVIII, RC and Fibrinogen but no significant differences between children with PCC compared to controls. Although the majority of children in our cohort showed coagulation profile within or close to normal ranges, we found that a higher proportion of children with PCC, and specifically those with a more severe spectrum characterized with three or more persisting symptoms, had abnormal D-dimer levels compared to other children that fully recovered from an acute SARS-CoV-2 infection.