Vitamin D and morbidity in children with Multisystem inflammatory syndrome related to Covid-19.

Background: Multisystem inflammatory syndrome (MIS-C) is a clinical presentation reported in children related to Coronavirus-19 infection who present with a toxic shock like syndrome. Vitamin D deficiency has been postulated to play a role with severity of coronavirus infection in adult patients and other viral respiratory infections. Objective: This study aims to investigate if severe vitamin D deficiency was associated with increased disease severity and cardiac involvement in MIS-C. Methods: This is a retrospective and single center study. We included hospitalized patients less than 18 years of age with diagnosis of MIS-C between March and July 2020. Severe vitamin D deficiency was defined as 25-OH vitamin D level < 10 ng/ml within 48 h of admission. The composite outcome severe disease included patients requiring inotropes, mechanical ventilation, and extracorporeal membrane oxygenation. Results: Of the 31 patients with MIS-C, 45% were male and 58% were African American. The median age was 8 (1-13) years. Ten patients had severe vitamin D deficiency with a mean level of 7.2 ng/ml. Ninety percent of patients with severe vitamin D deficiency had severe disease (P < 0.001). Patients with severe vitamin D deficiency had an increased risk of cardiac involvement (P < 0.001). Conclusions: We describe a potential association between severe vitamin D deficiency and severe disease in children presenting with MIS-C. Severe vitamin D deficiency predisposes patients for cardiovascular involvement and may play a critical role in the host immune response to COVID-19 infection. Future prospective studies at the basic science and clinical level should be pursued to better delineate this association.

Human blood CXCR5(+)CD4(+) T cells are counterparts of T follicular cells and contain specific subsets that differentially support antibody secretion.

Although a fraction of human blood memory CD4(+) T cells expresses chemokine (C-X-C motif) receptor 5 (CXCR5), their relationship to T follicular helper (Tfh) cells is not well established. Here we show that human blood CXCR5(+)CD4(+) T cells share functional properties with Tfh cells and appear to represent their circulating memory compartment. Blood CXCR5(+)CD4(+) T cells comprised three subsets: T helper 1 (Th1), Th2, and Th17 cells. Th2 and Th17 cells within CXCR5(+), but not within CXCR5(-), compartment efficiently induced naive B cells to produce immunoglobulins via interleukin-21 (IL-21). In contrast, Th1 cells from both CXCR5(+) and CXCR5(-) compartments lacked the capacity to help B cells. Patients with juvenile dermatomyositis, a systemic autoimmune disease, displayed a profound skewing of blood CXCR5(+) Th cell subsets toward Th2 and Th17 cells. Importantly, the skewing of subsets correlated with disease activity and frequency of blood plasmablasts. Collectively, our study suggests that an altered balance of Tfh cell subsets contributes to human autoimmunity.

Everything That Wheezes Is Not Asthma: A Case Report.

Background: This case report provides the general pediatrician with insight on a unique presentation of an already rare disease. Plastic bronchitis (PB) is an exceedingly rare disease that presents with the formation of casts in the endobronchial tree. This typically occurs in patients with congenital heart defects that have undergone repair, however, it is atypical to be seen in otherwise healthy patients. Influenza A, lymphatic abnormalities, and single ventricle physiology are the only proven causes of PB. Asthma, toxic inhalation, and acute chest syndrome, however, are a few of the many conditions that have been proposed to predispose patients toward developing PB. Case Presentation: Thus, it is important to discuss the case of a 9-year-old boy with a history of uncontrolled asthma who presented with cough, chills, weight loss, and fevers. This patient was initially treated with broad-spectrum antibiotics due to concerns for necrotizing pneumonia, but due to failure in improvement, a direct laryngoscopy and bronchoscopy was performed, revealing the diagnosis of PB. Although this patient had a history of uncontrolled asthma, this was the only predisposing respiratory condition that put him at risk of developing PB. This patient went on to be treated with corticosteroids, chest physiotherapy, inhaled fibrinolytics, and direct fibrinolytic therapy with marked improvement in symptoms and imaging. Conclusion: PB, though rare, is a condition that all pediatricians must keep in their minds when patients present with respiratory symptoms with an unclear etiology. The delay in diagnosis and treatment of patients with PB can be detrimental as expectoration of these casts can result in asphyxiation and death. This article goes on to remind all providers, at all levels, the importance of conducting a thorough history/physical examination, creating a broad differential, and treating each patient holistically.

Refeeding Syndrome with Hypoglycemia in a Severely Malnourished Infant.

A 5-mo-old severely malnourished 3.5 kg boy was brought to the emergency department with hypoglycemia, bradycardia, bradypnea, and hypothermia. His findings were likely due to severe malnutrition secondary to parental neglect. Resuscitation with dextrose containing intravenous fluids was promptly started. On day 2 of admission, refeeding was initiated. From that time, he had multiple hypoglycemic episodes along with hypophosphatemia, hypomagnesemia, and hypokalemia. Hypoglycemia was associated with the initiation of enteral feeding and an increase in calories and amounts of enteral feeding. Hypoglycemia associated with refeeding syndrome in infant has not been previously reported.

Cranial vault reduction cranioplasty in children with hydrocephalic macrocephaly.

Craniofacial surgeons are rarely presented patients with extreme hydrocephalic macrocephaly due to early diagnosis and treatment of the hydrocephalus. Macrocephaly can significantly limit or prohibit mobility, hygiene and can drastically change lifestyle and developmental issues. The authors herein report on four consecutive total cranial vault reduction cranioplasty procedures for correction of hydrocephalic macrocephaly. The patients had a reduction in cranial volume ranging from 111-641 mL. All patients survived the procedure. Improvement in head control and aesthetics were improved in all patients. All of the patients required at least one shunt revision following the procedure. We conclude that total cranial vault reshaping is safe and effective for the treatment of macrocephaly secondary to hydrocephalus.