Background Genetic deficiencies of immune system, referred to as inborn errors of immunity (IEI), serve as a valuable model to study human immune responses. In a multicenter prospective cohort, we evaluated the outcome of SARS‐CoV‐2 infection among IEI subjects and analyzed genetic and immune characteristics that determine adverse COVID‐19 outcomes. Methods We studied 34 IEI patients (19M/15F, 12 [min: 0.6‐max: 43] years) from six centers. We diagnosed COVID‐19 infection by finding a positive SARS‐CoV‐2 PCR test ( n = 25) and/or a lung tomography scoring (CORADS) ≥4 ( n = 9). We recorded clinical and laboratory findings prospectively, fitted survival curves, and calculated fatality rates for the entire group and each IEI subclass. Results Nineteen patients had combined immune deficiency (CID), six with predominantly antibody deficiency (PAD), six immune dysregulation (ID), two innate immune defects, and one in the autoinflammatory class. Overall, 23.5% of cases died, with disproportionate fatality rates among different IEI categories. PAD group had a relatively favorable outcome at any age, but CIDs and IDs were particularly vulnerable. At admission, presence of dyspnea was an independent risk for COVID‐related death (OR: 2.630, 95% CI; 1.198–5.776, p < .001). Concerning predictive roles of laboratory markers at admission, deceased subjects compared to survived had significantly higher CRP, procalcitonin, Troponin‐T, ferritin, and total‐lung‐score ( p = .020, p = .003, p = .014, p = .013, p = .020; respectively), and lower absolute lymphocyte count, albumin, and trough IgG ( p = .012, p = .022, p = .011; respectively). Conclusion Our data disclose a highly vulnerable IEI subgroup particularly disadvantaged for COVID‐19 despite their youth. Future studies should address this vulnerability and consider giving priority to these subjects in SARS‐Cov‐2 therapy trials.

Specific protocols define eligibility, conditioning, donor selection, graft composition and prophylaxis of graft vs. host disease for children and young adults undergoing hematopoietic stem cell transplant (HSCT). However, international protocols rarely, if ever, detail supportive care, including pharmaceutical infection prophylaxis, physical protection with face masks and cohort isolation or food restrictions. Supportive care suffers from a lack of scientific evidence and implementation of practices in the transplant centers brings extensive restrictions to the child's and family's daily life after HSCT. Therefore, the Board of the Pediatric Diseases Working Party (PDWP) of the European Society for Blood and Marrow Transplantation (EBMT) held a series of dedicated workshops since 2017 with the aim of initiating the production of a set of minimal recommendations. The present paper describes the consensus reached within the field of infection prophylaxis.

Background Despite the increasing performance of allogeneic hematopoietic cell transplantation over the last decades, graft‐versus‐host disease (GVHD) remains the main cause of morbidity and mortality. The efficacy of ruxolitinib against GVHD has been demonstrated in adult studies; however, very few studies have been conducted in children. Procedure This study aimed to evaluate the efficacy of ruxolitinib in 29 children with steroid‐refractory acute or chronic GVHD. Twenty‐five (87%) patients received at least three different immune modulator agents, including methylprednisolone, before initiating ruxolitinib. Results All grade 2 acute GVHD patients completely responded to ruxolitinib treatment; 82% of high‐grade (3‐4) acute GVHD patients and 80% of chronic GVHD (moderate‐severe) patients had at least a partial response. Of seven patients with bronchiolitis obliterans, five had a partial response after ruxolitinib. Of 29 patients, 22 were administered steroids at any time in the first month of acute GVHD or the first three months of chronic GVHD during ruxolitinib usage, which was significantly tapered by the end of the observation period. Conclusion Steroid‐refractory acute and chronic pediatric GVHD patients treated with ruxolitinib had a high overall response rate, with the additional benefit of steroid sparing.

Dornase alfa, the recombinant form of the human DNase I enzyme, breaks down neutrophil extracellular traps (NET) that include a vast amount of DNA fragments, histones, microbicidal proteins and oxidant enzymes released from necrotic neutrophils in the highly viscous mucus of cystic fibrosis patients. Dornase alfa has been used for decades in patients with cystic fibrosis to reduce the viscoelasticity of respiratory tract secretions, to decrease the severity of respiratory tract infections, and to improve lung function. Previous studies have linked abnormal NET formations to lung diseases, especially to acute respiratory distress syndrome (ARDS). It is well known that novel Coronavirus disease 2019 (COVID-19) pneumonia progresses to ARDS and even multiple organ failure. High blood neutrophil levels are an early indicator of COVID-19 and predict severe respiratory diseases. Also it is reported that mucus structure of COVID-19 is very similar to cystic fibrosis due to the accumulation of excessive NET in the lungs. In this study, we showed the recovery of three COVID-19 patients after including Dornase alfa in their treatment. We followed clinical improvement in the radiological analysis (2-of-3 cases), oxygen saturation (SpO 2 ), respiratory rate, disappearing of dyspnea, coughing and a decrease in NET formation and SARS-CoV-2 viral load after the treatment. Also here, we share our preliminary results suggesting that Dornase alfa has an anti-viral effect against SARS-CoV-2 infection in a green monkey kidney cell line, Vero, and a bovine kidney cell line, MDBK without determined cytotoxicity on healthy peripheral blood mononuclear cells.

The novel coronavirus pneumonia, which was named later as coronavirus disease 2019 , is caused by the severe acute respiratory syndrome coronavirus 2, namely SARS-CoV-2. It is a positive-strand RNA virus that is the seventh coronavirus known to infect humans. The COVID-19 outbreak presents enormous challenges for global health behind the pandemic outbreak. The first diagnosed patient in Turkey has been reported by the Republic of Turkey Ministry of Health on March 11, 2020. In May, over 150,000 cases in Turkey, and 5.5 million cases around the world have been declared. Due to the urgent need for a vaccine and antiviral drug, isolation of the virus is crucial. Here, we report 1 of the first isolation and characterization studies of SARS-CoV-2 from nasopharyngeal and oropharyngeal specimens of diagnosed patients in Turkey. This study provides an isolation and replication methodology,and cell culture tropism of the virus that will be available to the research communities.