[Pediatric refractory acute immune thrombocytopenic purpura secondary to asymptomatic SARS-CoV2]. / Face à la COVID-19. Purpura thrombopénique immunologique pédiatrique réfractaire secondaire à une infection asymptomatique à SARS-CoV2.

Acute immune thrombocytopenic purpura (ITP) has been revealed as an uncommon complication of COVID-19 in children. Severe bleeding may occur but is rarely life threatening. Management is based on the severity of bleeding symptoms and the degree of thrombocytopenia. We report the case of a 7-year-old girl with severe acute ITP secondary to a COVID-19 infection -without any respiratory symptoms. The initial clinical examination showed a large bulging mediodorsal hematoma, purpuric lesions, and posterior pharyngeal hemorrhage. The patient was monitored in a pediatric intensive care unit. Initial medical management consisted of intravenous immunoglobulins and systemic steroids. Despite this treatment, bleeding and thrombocytopenia worsened, and secondary macroscopic haematuria occurred, requiring 6-hourly platelet transfusions and increased steroid doses to obtain sufficient hemostasis. This case presents a rare and severe acute pediatric ITP secondary to asymptomatic SARS-COV2 which was refractory to initial management and opens the discussion to second line therapeutic interventions.

Le purpura thrombopénique immunologique aigu (PTI) s'est révélé comme une complication inhabituelle de la COVID-19 en pédiatrie. Une hémorragie sévère peut survenir, mais constitue rarement une menace vitale. La prise en charge dépend de la sévérité des signes hémorragiques et du niveau de la thrombopénie. Nous rapportons le cas clinique d'une enfant de 7 ans avec diagnostic de PTI sévère aigu secondaire à la COVID-19, sans symptôme respiratoire. L'examen clinique initial mettait en évidence un large hématome médiodorsal bombant, des lésions purpuriques, ainsi qu'un saignement pharyngé postérieur. Une surveillance en unité de soins intensifs avec administration d'immunoglobulines intraveineuses et de corticoïdes systémiques a été initiée. Malgré la thérapeutique, les saignements se sont intensifiés, avec apparition secondaire d'une hématurie macroscopique justifiant la réalisation de transfusions plaquettaires continues et la majoration des doses de corticoïdes jusqu'à l'obtention de l'hémostase. Ce cas clinique relate un cas rare et sévère de PTI aigu pédiatrique secondaire à une infection à SARS-COV2 réfractaire au traitement habituel et ouvre la discussion aux thérapeutiques de deuxième ligne.

Pancytopenia Due to Vitamin B12 and Folic Acid Deficiency-A Case Report.

We report a case of severe pancytopenia in a 15-year-old patient due to a severe deficiency in vitamin B12 and folic acid, probably of nutritional origin. The clinical and biological course was favorable after vitamin supplementation. With this case, we discuss the diagnostic approach of pancytopenia with megaloblastic anemia in children and adolescents, as well as the mechanisms involved in vitamin B12 and B9 deficiency. Hypovitaminosis B12 is known in its severe form but its diagnosis is often made difficult by insidious signs and symptoms. Traditional intramuscular replacement therapy has now proven to be effective orally. The clinical manifestations of folic acid deficiency are relatively similar to those of vitamin B12 deficiency, reflecting their intricate co-enzymatic functions. Its supplementation is administered orally.

Langerhans Cell Histiocytosis With Vertebral Involvement Diagnosed and Treated Over the Last 15 Years in a Single Canadian Pediatric Academic Institution.

We report 11 children with vertebral lesion of Langerhans cell histiocytosis (LCH) diagnosed and treated between 2000 and 2015. Vertebral lesions were usually present at LCH diagnosis. No child developed neurologic symptoms. Among 29 vertebral lesions, only 2 were unstable. Chemotherapy was used in all children but 3. A LCH recurrence was observed in 6 patients, involving vertebrae in 4 cases. All children were disease-free at their last follow-up. Sequelae were more often radiologic than clinical. Since potential recurrences and incomplete bone regeneration exist, discussion about optimal treatment and long-term follow-up of vertebral lesions are essential.

Gray Zone Lymphoma Arising in the Neck of a Teenager With a Germline Mutation in TP53.

Gray zone lymphoma is an aggressive disease for which appropriate management is still debated. We report a 15-year-old girl with a cervical mass, an enlarged ipsilateral tonsil, and anemia. Both sites showed hypermetabolism on F18-FG positron emission tomography/CT. Surgical resection was diagnostic of Epstein-Barr virus-negative gray zone lymphoma cervical and tonsillar involvement. No abnormality was found in cytogenetic analysis on tumor cells. However, exome sequencing in peripheral blood DNA revealed a germline mutation in TP53. Complete response was achieved after surgery and 6 cycles of rituximab with dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin regimen.