Coagulation profiles and percentiles in neonates with hypoxic-ischemic encephalopathy undergoing therapeutic hypothermia: A step toward more accurate transfusion thresholds.

BACKGROUND: In the literature, there are no studies about the transfusion threshold for neonates with hypoxic-ischemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH). In order to facilitate accurate interpretation of coagulation results in these neonates, we aimed to generate specific reference intervals in this specific population. METHODS: This retrospective study included all HIE neonates admitted from 2014 to 2022 to undergo TH. All infants during TH underwent blood exams, including the coagulation profile. Our primary outcome was to assess the estimates of the 3rd, 10th, 25th, 50th, 75th, 90th, and 97th percentiles for each parameter on admission (before transfusion). By the receiver operating characteristic (ROC) analysis, the area under the ROC curve (AUC) and the best cut-off point were used to evaluate the ability of the prothrombin time expressed as international normalized ratio (PT-INR) to predict the risk of any bleeding. RESULTS: A total of 143 infants were included in this study. On admission, the median fibrinogen value was 205 mg/dL, prothrombin time 18.6 seconds, PT-INR 1.50, activated partial thromboplastin time 38.3 seconds, thrombin time 18.6 seconds, antithrombin 57.0%. The optimal cut-off of PT-INR in predicting the risk of any bleeding was greater than 1.84 (AUC .623, p = .024). CONCLUSION: For the first time, we proposed the percentiles of coagulation parameters in our cohort of neonates with HIE. Furthermore, we found that a PT-INR greater than 1.84 can significantly predict the risk of any bleeding. Further studies are needed to determine if a restrictive versus a liberal transfusion approach can be equally safer for these high-risk infants.

Otogenic lateral sinus thrombosis in children: proposal of an experience-based treatment flowchart.

PURPOSE: To describe the prevalent clinical, laboratory, and radiological features of otogenic lateral sinus thrombosis (OLST) in children; to identify clinical predictors of outcome; to propose a management algorithm derived from experience. METHODS: A retrospective review was conducted of the clinical records of patients with OLST, treated in a single tertiary care referral center for pediatric disease from 2006 to 2017. The inclusion criteria were pediatric age (0-16 years) and OLST diagnosis confirmed by a pre- and post-contrast CT or venography-MRI scan. Primary outcome measures were early (1-2 months) and late (6 months) sinus recanalization assessed by means of neuroimaging. RESULTS: Twenty-five patients (8 females and 17 males; mean age = 6 ± 3 years) were included. A genetic abnormality associated with thrombophilia was found in 24 (96%) patients. At diagnosis, anticoagulant treatment with low-molecular-weight heparin (LMWH) was started in all subjects, while surgical treatment (mastoidectomy and tympanostomy tube insertion) was performed in 16/25 (64%) patients. Follow-up neuroimaging showed lateral sinus recanalization in 12/25 (48%) patients after 1-2 months and in 17/25 (68%) after 6 months. At multivariate logistic regression analysis, no significant predictors of the early and late neuroradiological outcome were found. CONCLUSIONS: All children with OLST should be screened for thrombophilia to decide on treatment duration and to assess the need for future antithrombotic prophylaxis. Immediately after diagnosis, anticoagulant treatment with LMWH should be started according to the international guidelines. Instead, our experience suggests that surgical treatment should not be indicated in all patients, but decided on a case-to-case basis.

Kaolin-activated thromboelastography and standard coagulation assays in cyanotic and acyanotic infants undergoing complex cardiac surgery: a prospective cohort study.

BACKGROUND AND AIMS: Several studies report the use of thromboelatography (TEG) to monitor coagulation in pediatric cardiac surgery. The aim of this study was to compare baseline and intraoperative TEG, TEG-functional fibrinogen, and standard coagulation assays in children with cyanotic and acyanotic congenital heart disease (CHD) undergoing cardiac surgery. METHODS: This is a prospective observational study of 63 children aged <24 months undergoing cardiac surgery with cardiopulmonary bypass (CPB). Exclusion criteria included preoperative anticoagulant therapy and hepatic failure. We collected blood at anesthesia induction (T1), at lowest temperature after CPB start (T2), and after heparin neutralization (T3). Coagulation was evaluated by TEG (reaction time [R]), k, alpha-angle, maximum amplitude (MA), MA-fibrinogen (MA-fib), and by standard coagulation assays (prothrombin time, activated partial thromboplastin time, fibrinogen level, platelet [PLT] count). RESULTS: Sixty-three patients were enrolled (38 cyanotic and 25 acyanotic). Median age was 4 [IQR 2-6] months and median weight was 5 [IQR 3.7-6.5] kg. Most common surgeries were: ventricular septal defect repair (n = 13), Fallot correction (n = 11), and arterial switch operation (n = 10). Cyanotic and acyanotic children were well matched: R, k, MA, and MA-fib at T1, T2, and T3 were not significantly different between cyanotic and acyanotic children. At T2, significant correlations were showed between MA and PLT count (r = 0.4; P = 0.0008) and k and plasma fibrinogen level (r = -0.54; P < 0.0001). At T3, significant correlations were showed between MA and PLT count (r = 0.5; P < 0.0001), G and PLT count (r = 0.6; P < 0.0001), and MA-fib and plasma fibrinogen level (r = 0.5; P = 0.002). CONCLUSIONS: According to our findings, cyanosis does not affect TEG parameters in children with CHD. PLT count and plasma fibrinogen significantly correlated (are significantly associated) with MA and MA-fib respectively, suggesting that use of TEG after protamine administration may be prompted for improved hemostatic monitoring in the perioperative phase.

Antiplatelet Effect of Melatonin through Breastfeeding: A Pediatric Case Report.

We present a pediatric case of the antiplatelet effect of melatonin taken through breast milk in an 18-month-old child. The child was referred to our hematology outpatient clinic because of bleeding episodes that she presented since birth. Blood tests excluded the presence of blood coagulation diseases. The family history was negative for bleeding disorders. The child did not consume any drugs, food supplements, herbal teas or infusions. We performed an aggregation platelet test, which showed a reduced platelet aggregation. Shortly before, the baby had been breastfed. We speculated that breast milk could interfere with the result of the test; therefore, we decided to repeat the test in a fasting state. This time the test showed a normal platelet aggregation time. We learned that the child's mother was taking a mixture of valerian and melatonin. Thus, we decided to suspend maternal intake of melatonin and perform a new platelet aggregation test after three months. The test results were negative. After the suspension of melatonin, the patient did not present further bleeding events. In this case, melatonin, through the inhibition of platelet aggregation, had an important role on the hemostatic system of the child. Melatonin is considered as a dietary supplement and is mostly available as an alternative medicine without formal prescription and dosage regulation. It is important, especially during breastfeeding, to investigate personal and medication history, including also homeopathic remedies or dietary supplements.

Plasminogen Activator Inhibitor-1 and Vitamin D Association in the Overweight and Obese Pediatric Population.

BACKGROUND: Childhood overweight and obesity have been described by the World Health Organization as noncommunicable diseases and among the greatest public health threats since they have reached epidemic proportions. A child with obesity risks becoming an adult with obesity and developing metabolic and hemostatic disorders which are the basis for the development of coronary heart diseases. Recently, a number of clinical reports have demonstrated that both an increase in plasminogen activator inhibitor-1 (PAI-1) and a deficiency in 25OH-vitamin D3 (VD) are associated with an increase in thrombotic episodes. METHODS: PAI-1 and VD levels were measured in 259 clinically overweight and obese children aged between 2 and 18 years enrolled in the Nutritional Education Program of the Bambino Gesù Children's Hospital and Research Institute of Rome (Italy) and 80 normal-weight subjects. RESULTS: We observed increased HOMA-IR, PAI-1, and other inflammation indices associated with decreased VD levels when compared to normal-weight children. CONCLUSIONS: Our results demonstrated that overweight and obesity are correlated with higher levels of the inflammation index. Moreover, our patients show high PAI-1 and low VD levels, confirming the high thrombotic risk in our pediatric population.

Contribution of vitamin D3 and thiols status to the outcome of COVID-19 disease in Italian pediatric and adult patients.

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARSCoV-2), was declared a global pandemic by the World Health Organization (WHO) on March 2020, causing unprecedented disease with million deaths across the globe, mostly adults. Indeed, children accounted for only a few percent of cases. Italy was the first Western country struck by the COVID-19 epidemic. Increasing age, which is one of the principal risk factors for COVID-19 mortality, is associated with declined glutathione (GSH) levels. Over the last decade, several studies demonstrated that both vitamin D (VD) and GSH have immunomodulatory properties. To verify the association between VD, GSH and the outcome of COVID-19 disease, we conducted a multicenter retrospective study in 35 children and 128 adult patients with COVID-19. Our study demonstrated a hypovitaminosis D in COVID-19 patients, suggesting a possible role of low VD status in increasing the risk of COVID-19 infection and subsequent hospitalization. In addition, we find a thiol disturbance with a GSH depletion associated to the disease severity. In children, who fortunately survived, both VD and GSH levels at admission were higher than in adults, suggesting that lower VD and thiols levels upon admission may be a modifiable risk factor for adverse outcomes and mortality in hospitalized patients with COVID-19.

Reference Intervals for Coagulation Parameters in Developmental Hemostasis from Infancy to Adolescence.

Background: The objective of this study was to establish the age and sex-dependent reference intervals for coagulation assays evaluated in healthy children, ranging from 0 days to 16 years old. Methods: PT, aPTT, Fibrinogen (functional), Antithrombin activity, Protein C anticoagulant activity, Protein S free antigen, Thrombin time, D-Dimer, Von Willebrand Factor antigen, Lupus anticoagulant (screening), extrinsic and intrinsic pathway factors, and activated Protein C resistance were evaluated using STA-R Max2. Results: A total of 1280 subjects (671 males and 609 females) were divided into five groups, according to their age: 0-15 days (n = 280, 174 M and 106 F), 15-30 days (n = 208, 101 M and 107 F), 1-6 months (n = 369, 178 M and 191 F), 6-12 months (n = 214, 110 M and 104 F), and 1-16 years (n = 209, 108 M and 101 F). The 95% reference intervals and the 90% CI were established using the Harrell-Davis bootstrap method and the bootstrap percentile method, respectively. Conclusions: The present study supports the concept that adult and pediatric subjects should be evaluated using different reference intervals, at least for some coagulation tests, to avoid misdiagnosis, which can potentially lead to serious consequences for patients and their families, and ultimately the healthcare system.

Study of the Association between Thiols and Oxidative Stress Markers in Children with Obesity.

Obesity has reached epidemic proportions, and the World Health Organization defined childhood overweight and obesity as a noncommunicable disease that represents the most serious public health challenges of the twenty-first century. Oxidative stress, defined as an imbalance between oxidants and antioxidants causing an impairment of the redox signals, is linked to the development of metabolic diseases. In addition, reactive oxygen species generated during metabolic disorder could increase inflammation, causing the development of insulin resistance, diabetes, and cardiovascular disease. We analyze serum levels of cysteine (Cys), cysteinyl-glycine (Cys-Gly), homocysteine (Hcy), and glutathione (GSH), and other markers of oxidative stress, such as thiobarbituric acid reactive substances (T-BARS), 8-isoprostane, and protein carbonyl in our children with obesity. Total antioxidant status was also determined. We found lower GSH and Cys-Gly levels, and higher Hcy and oxidative stress markers levels. We also found a positive correlation between Body Mass Index (BMI), Cys, GSH, and Hcy levels, between insulin and Cys levels, and between BMI and the homeostasis model assessment-estimated insulin resistance (HOMA-IR) with 8-isoprostane levels. Finally, we found a correlation between age and GSH and Cys levels. The deficiency of GSH could be restored by dietary supplementation with GSH precursors, supplying an inexpensive approach to oppose oxidative stress, thus avoiding obesity complications.

Pediatric Mechanical Circulatory Support: Pathophysiology of Pediatric Hemostasis and Available Options.

Pediatric mechanical circulatory support (MCS) is considered a strategy for heart failure management as a bridge to recovery and transplantation or as a destination therapy. The final outcome is significantly impacted by the number of complications that may occur during MCS. Children on ventricular assist devices (VADs) and extracorporeal membrane oxygenation (ECMO) are at high risk for bleeding and thrombotic complications that are managed through anticoagulation. The first detailed guideline in pediatric VADs (Edmonton Anticoagulation and Platelet Inhibition Protocol) was based on conventional antithrombotic drugs, such as unfractionated heparin (UFH) and warfarin. UFH is the first-line anticoagulant in pediatric MCS, although its profile is not considered optimal in pediatric setting. The broad variation in heparin doses among children is associated with frequent occurrence of cerebrovascular accidents, bleeding, and thrombocytopenia. Direct thrombin inhibitors (DTIs) have been utilized as alternative strategies to heparin. Since 2018, bivalirudin has become the chosen anticoagulant in the long-term therapy of patients undergoing MCS implantation, according to the most recent protocols shared in North America. This article provides a review of the non-traditional anticoagulation strategies utilized in pediatric MCS, focusing on pharmacodynamics, indications, doses, and monitoring aspects of bivalirudin. Moreover, it exposes the efforts and the collaborations among different specialized centers, which are committed to an ongoing learning in order to minimize major complications in this special pediatric population. Further prospective trials regarding DTIs in a pediatric MCS setting are necessary and in specific well-designed randomized control trials between UFH and bivalirudin. To conclude, based on the reported literature, the clinical use of the bivalirudin in pediatric MCS seems to be a value added in controlling and maybe reducing thromboembolic complications. Further research is necessary to confirm all the results provided by this literature review.

Calibrated automated thrombogram values in infants with cardiac surgery before and after cardiopulmonary bypass.

INTRODUCTION: Impaired thrombin generation has been associated to increase bleeding after cardiac surgery with cardiopulmonary bypass (CPB), especially in children. The aim of this study was to evaluate standard coagulation assay, thrombin generation by calibrated automated thrombogram (CAT), thromboelastography (TEG) and procoagulant phospholipids (PPL) activity in infants undergoing cardiac surgery with CPB. MATERIALS AND METHODS: Prospective observational study performed in children aged <24months undergoing cardiac surgery with CPB. Exclusion criteria were preoperative coagulopathy or anticoagulant therapy. Coagulation was evaluated by standard coagulation assays (prothrombin time, activated partial thromboplastin time, fibrinogen level, platelet count), TEG, CAT and PPL at anaesthesia induction (T1) and after 12h (T2). Perioperative bleeding management was performed according to the institutional guidelines. RESULTS: Forty-nine children aged <24months were enrolled. At T1 ETP and peak height evaluated by CAT were significantly lower in infants aged <6months. Standard coagulation tests, TEG and PPL did not correlate with age. At T2 platelet count, plasmatic fibrinogen level, all TEG parameters, ETP and peak height by CAT were significantly impaired compared to baseline values (T1), despite allogeneic blood product transfusions. CONCLUSIONS: Thrombin generation is significantly impaired in children affected by congenital heart disease, compared to healthy children and adults. CAT parameters resulted age-dependent, and thrombin generation is lower in infants aged <6months. After cardiac surgery with CPB, a coaugulopathy, revealed by CAT, TEG, but not by PT and aPTT assays, is persistent 12h after surgery despite transfusions of blood products.

Novel plasminogen and hyaluronate sodium eye drop formulation for a patient with ligneous conjunctivitis.

PURPOSE: The development, analysis, and first clinical use of a novel eye drop formulation of plasminogen and hyaluronate sodium for the treatment of a patient with ligneous conjunctivitis (LC) are described. SUMMARY: LC is a chronic inflammatory disorder of the eye that can in rare cases lead to corneal involvement and subsequent blindness. Topically administered plasminogen is an effective treatment for LC; however, the lack of a specific and validated formulation of plasminogen for topical treatment can constitute a gap in the quality of care. A novel formulation of plasminogen and hyaluronate sodium for the treatment of LC was developed by combining commercially available products. Through a series of tests, including microbiological, viscosity, and pH analyses, the novel eye drop formulation was demonstrated to have constant activity (3.3 IU/mL or greater), to be microbiologically stable (i.e., sterile), and to be safe enough for daily administration. The first clinical application of the novel eye drop formulation was in the case of a nine-year-old girl with LC affecting both eyes. Initially, the girl's parents administered two drops every three hours to the left eye each day while the girl was awake. On examination after 30 days of daily use of the eye drop formulation, the patient was found to have a clear cornea and no membrane development on the conjunctiva; the formulation was subsequently administered in both eyes, with positive results. CONCLUSION: A new formulation of plasminogen plus hyaluronate sodium was developed, tested, and used successfully in a girl with LC.