New primary immunodeficiencies 2021 context and future.

PURPOSE OF REVIEW: Primary immunodeficiency diseases (PIDs), also called inborn errors of immunity (IEI), are genetic disorders classically characterized by an increased susceptibility to infection and/or disruption in the regulation of an immunologic pathway. This review summarizes and highlights the new IEI disorders in the IUIS 2019 report and 2020 interim report and discusses the directions for the future management of PIDs. RECENT FINDINGS: Since 2017, the International Union of Immunologic Societies (IUIS) IEI committee has updated the IUIS classification of IEIs with 88 new gene defects and 75 new immune disorders. The increased utilization of genetic testing and advances in the strategic evaluation of genetic variants have identified, not only novel IEI disorders, but additional genetic causes for known IEI disorders. Investigation of potential immune susceptibilities during the ongoing COVID-19 pandemic suggests that defects in Type I interferon signalling may underlie more severe disease. SUMMARY: The rapid discovery of new IEIs reflects the growing trend of applying genetic testing modalities as part of medical diagnosis and management.In turn, elucidating the pathophysiology of these novel IEIs have enhanced our understanding of how genetic mutations can modulate the immune system and their consequential effect on human health and disease.

Clinical and Laboratory Characteristics of Children With SARS-CoV-2 Infection

PURPOSE OF THE STUDY: To characterize demographic, clinical, and laboratory characteristics of children with suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and to evaluate coinfections with common respiratory tract pathogens. STUDY POPULATION: Included 422 participants ages 0 to 18 years with household exposure or contact with someone with SARS-CoV-2 or with respiratory symptoms who presented to a pediatric emergency department in an academic center in Turkey between March 23rd and July 23rd, 2020. METHODS: This cross-sectional study assessed SARS-CoV-2 suspected cases per guidelines set by the Turkish Ministry of Health during this time period. Demographic information, SARS-CoV-2 exposure, preexisting comorbidities, and disposition information was collected. Quantitative real time reverse transcriptase polymerase chain reaction test and panel testing for other common respiratory pathogens in nasopharyngeal secretions were performed in asymptomatic cases with SARS-CoV-2 exposure in the prior 14 days. Complete blood count, C-reactive protein, serum electrolytes, procalcitonin, liver function tests, creatine phosphokinase levels, creatinine, and coagulation parameters were assessed in subjects requiring hospitalization. Chest x-ray (CXR), as well as chest computed tomography (CT) in the event of a negative CXR, was performed in the symptomatic suspected cases. COVID-19 disease severity was classified according to the published literature in 2020. RESULTS: There were 57.6% (n = 243) boys and 42.4% (n = 179) girls. Of the 18.4% who were SARS-CoV-2 positive, 78.2% had a positive adult household contact and 29.5% were asymptomatic. All but 3 did not have an underlying comorbidity. The SARS-CoV-2 positive group (median 132.6 months) was older than the SARS-CoV-2 negative group (median 51.9 months). Fever was the most common sign in 51.2% of SARS-CoV-2 positive subjects followed by cough, myalgia or weakness, headache, sore throat, nausea or vomiting, and diarrhea. Rhinorrhea was seen only in the SARS-CoV-2 negative group. Most (89.4%) of the positive cases were asymptomatic or mild, and 29.5% were admitted. No critical cases and no mortality was reported. In the SARS-CoV-2 positive cases, 8 had an abnormal CXR and 11 had an abnormal chest CT. More SARS-CoV-2 negative cases had a CT-positive pneumonia than positive cases (18% vs 14%). SARS-CoV-2 positive cases had significantly lower white blood cell and platelet counts and significantly higher acute phase reactants, lactate dehydrogenase (LDH), and creatine phosphokinase. The rate of viral coinfection with SARS-CoV-2 was 16.4% (n = 21) with the most common copathogen being rhinovirus, followed by human metapneumovirus, adenovirus, bocavirus, respiratory syncytial virus, and both respiratory syncytial virus and rhinovirus. CONCLUSIONS: SARS-CoV-2 infection generally caused mild symptoms in children with a favorable clinical course in those admitted to the hospital. One third of the positive cases were asymptomatic. Fever and cough were common, but rhinorrhea was typically absent. Most of the SARS-CoV-2 positive patients had a normal CXR and chest CT.