key: cord-0912576-bxygvh7q authors: Yilmaz Topal, Ozge; Metin, Ayse; Kulhas Celik, İlknur; Metbulut, Azize Pinar; Alim Aydin, Selma; Kanik Yuksek, Saliha; Ozkaya Parlakay, Aslinur title: Clinical characteristics of COVID‐19 in children and young adolescents with inborn errors of immunity date: 2021-09-24 journal: Pediatr Allergy Immunol DOI: 10.1111/pai.13661 sha: be7eb4d8eecf54f59f18cbb25d4f08b7047ecd9f doc_id: 912576 cord_uid: bxygvh7q The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread across the globe, and the World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a pandemic in mid-March of 2020. To the Editor, The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread across the globe, and the World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a pandemic in mid-March of 2020. In the pediatric age group, symptomatic COVID-19 has been mostly reported in children with inborn errors of immunity (IEI), chronic lung disease, and heart disease. 1 Patients with IEI can be expected to have more severe illness. Moreover, due to weak cellular immunity and viral control, more severe disease is expected in patients with combined immunodeficiencies than in those with humoral defects. 2 However, other authors have proposed that the opposite may be expected in immunocompromised patients. In children with IEI, the lack of the pro-inflammatory cytokine storm implicated in the pathogenesis of severe COVID-19 may protect these patients from multiple organ failure. 3 Therefore, we aimed to deter- Numbers and percentages were reported for discrete variables; continuous variables were expressed as mean and standard deviation for data with normal distribution and as median and interquartile range (IQR) for non-normally distributed data. The characteristics of the previously followed IEI patients who had COVID-19 infection are given in Table 1 . Contact status and test results of the patients are presented in Figure 1 . Therefore, a total of 10 (31.25%) of the 32 patients with confirmed SARS-CoV-2 infection were hospitalized. Among the hospitalized patients, 3 (30%) had predominantly antibody deficiency, 3 (30%) had congenital defects of phagocyte number or function, 2 (20%) had defects in intrinsic and innate immunity, 1 (10%) had combined immunodeficiencies with associated or syndromic features, and 1 patient (10%) had phenocopies of IEI. None of the patients died. It has been reported in the literature that the incidence of COVID-19 in children is lower than in adults. 4 In an international study, 94 COVID-19 patients with IEI (32 patients were <18 years old) were reported and 9 of them died. Two of the patients were in the pediatric age group; one had a phagocyte defect and another had immune dysregulation disorder. 11 These studies suggest that there is significant heterogeneity in disease severity among these patients. However, it seems that older age is consistently associated with poorer prognosis. The literature also includes a few articles reporting COVID-19 outcomes in patients followed up due to antibody deficiency. [12] [13] [14] Most of the patients with COVID-19 in our study were diagnosed with predominant antibody deficiency. In the literature, mortality was low in pediatric patients with IEI, similar to the other data related to children in our study. There is no financial support. Authors indicate no such interest. Due to the nature of this research, participants of this study did not agree for their data to be shared publicly, so supporting data is not available. Epidemiology of COVID-19 among children in China Impact of SARS-CoV-2 pandemic on patients with primary immunodeficiency COVID-19: consider cytokine storm syndromes and immunosuppression A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating personto-person transmission: a study of a family cluster Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: summary of a report of 72 314 cases from the Chinese Center for Disease Control and Prevention Epidemiological, Clinical, and Laboratory Features of Children With COVID-19 in Turkey Primary immunodeficiency diseases in COVID-19 pandemic: a predisposing or protective factor? COVID-19 in patients with primary and secondary immunodeficiency: The United Kingdom experience Clinical outcome, incidence, and SARS-CoV-2 infection-fatality rates in Italian patients with inborn errors of immunity Minor Clinical Impact of COVID-19 Pandemic on Patients With Primary Immunodeficiency in Israel Coronavirus disease 2019 in patients with inborn errors of immunity: An international study The clinical observation of a patient with common variable immunodeficiency diagnosed as having coronavirus disease 2019 A possible role for B cells in COVID-19? Lesson from patients with agammaglobulinemia Two X-linked agammaglobulinemia patients develop pneumonia as COVID-19 manifestation but recover