Children with SARS-CoV-2 infection have been consistently described with milder clinical outcomes compared to adults. However, data pertaining to the clinical evolution of SARS-CoV-2 infection in children with cancer remain scarce. In this descriptive cohort study, we report the clinical characteristics and outcomes of 31 pediatric oncology patients with SARS-CoV-2 infection in the province of Quebec, Canada. Most patients were asymptomatic or had mild symptoms, with only 2 COVID-19-related hospitalizations and no COVID-19-related deaths. The favorable outcomes in our cohort may be explained by Quebec's universal access to health care and regionalization of pediatric oncology care in tertiary centers exclusively.

Congenital erythropoietic porphyria (CEP) is caused by a defect in the heme biosynthesis pathway of the enzyme uroporphyrinogen III synthase (UROS) leading to an accumulation of non-physiological porphyrins. The exposure of accumulated porphyrins to sunlight causes severe photosensitivity, chronic intravascular hemolysis and, eventually, irreversible mutilating deformities. Several supportive therapies such as strict sun avoidance, physical sunblocks, red blood cells transfusion, hydroxyurea and splenectomy are commonly used in the management of CEP. Currently, the only available curative treatment of CEP is HSCT. We present a child with a very early diagnosis of CEP, who became the youngest successful HSCT for CEP.

Thromboembolism is a major complication of nephrotic syndrome (NS). Hypoalbuminemia, loss of anticoagulant proteins, increased procoagulant proteins, hemoconcentration, and platelet activation contribute to a hypercoagulable state. Despite being well-described, the optimal management of thromboembolism in NS remains unclear. Rivaroxaban, a direct factor-Xa inhibitor has recently been shown to be safe and efficacious in treating pediatric venous thromboembolism but has not been well studied in NS. We present an adolescent with steroid-dependent NS, deep vein thrombosis and submassive pulmonary embolism successfully treated with rivaroxaban. We perform a systematic review of the reported safety and efficacy of direct factor-Xa inhibitor in this population.

Background/Objectives: A striking procoagulant state induced by SARS-CoV-2 (COVID-19) infection has been reported in adults, with many hospitalized patients developing thrombosis despite prophylactic anticoagulation. Reports on the characteristics of COVID-19-associated coagulopathy are scarce in the pediatric population and thromboprophylaxis use is heterogeneous across pediatric centers. To characterize laboratory and clinical outcomes of COVID-19-associated coagulopathy in children and to assess prophylactic anticoagulation use. Design/Methods: Prospective multicenter observational cohort study including all patients from 0 to 18 years of age admitted to one of the pediatric university health centers in the province of Québec, Canada, with confirmed COVID-19 infection from February 1 to July 1, 2021. Patient-level data including laboratory parameters, treatment and outcomes were obtained via chart review. Results: Included were 79 children hospitalized with COVID-19-related symptoms, multisystem inflammatory syndrome in children or an incidental finding of asymptomatic infection. When assessed, hemostatic parameters demonstrated elevation in D-dimers in 94.7%, fibrinogen in 60%, prothrombin time in 51.9%, and activated thromboplastin time in 18.5%. Platelet counts were normal in 91.3% of patients. Ten patients (12.3%) received thromboprophylaxis with low molecular weight heparin, 7 (8.9%) with aspirin and 1 (1.3%) with both. We observed one thrombosis and one major bleed, both attributable to an alternate diagnosis other than COVID-19 infection. Conclusion: The most consistent abnormal hemostatic parameters observed in this study were elevated D-dimers and fibrinogen. No thrombosis ascribable to COVID-19 infection has been observed in this pediatric cohort, despite relatively infrequent anticoagulant prophylaxis. There have been no bleeding events attributable to thromboprophylaxis.