Safety of mRNA-based COVID-19 vaccination in paediatric patients with a PEG-asparaginase allergy.

Background: Children treated for a malignancy are at risk to develop serious illness from a COVID-19 infection. Pegylated E. coli asparaginase (PEG-asparaginase) is used in the treatment of acute lymphoblastic leukemia. Allergy to this drug is common and both asparaginase and polyethylene glycol (PEG) are identified as possible antigens. The mRNA-based vaccines against COVID-19 contain PEG as a stabilizing component. Methods: We developed a protocol to be able to safely vaccinate children with a PEG-asparaginase allergy. All patients with a history of allergy to PEG-asparaginase have been included and skin prick testing for various PEGs was performed before vaccination with the mRNA Pfizer-BioNTech COVID-19 vaccine. Results: Twelve children between six and 16 years old were vaccinated, without allergic reaction. None of them got a positive skin prick test for PEG. Ten patients had pre-existing IgG or IgM antibodies against PEG. Conclusion: Children with a PEG-asparaginase allergy can be safely vaccinated against COVID-19 with mRNA vaccines containing PEG irrespective of IgG/IgM antibodies to PEG-asparaginase. Routine skin prick testing in patients with PEG-asparaginase allergy does not seem to be of added value.

Safety and effectiveness of omalizumab for the treatment of chronic urticaria in pediatric patients.

BACKGROUND: Evidence on safety and effectiveness of omalizumab for treatment of chronic urticaria in pediatric patients is scarce and limited to case reports. In particular, drug survival of omalizumab has not yet been investigated, which is a key element in the evaluation of its clinical performance. The aim of this study was to investigate safety, effectiveness, and drug survival rates of omalizumab in a daily practice cohort of pediatric patients with chronic urticaria (CU). METHODS: This is a multicenter study including all pediatric patients from an academic center (Wilhelmina Children's Hospital) and a general center (Diakonessenhuis Hospital) in the Netherlands, who started omalizumab treatment before the age of 18 years. Data on safety, effectiveness, time to discontinuation, and reasons for discontinuation of treatment were assessed. Drug survival of omalizumab was estimated using the Kaplan-Meier survival analysis. RESULTS: A total of 38 patients, who started treatment between January 2014 and January 2020, were included. Most patients (68.4%) used omalizumab without reporting any side effects and a complete or good response to treatment was achieved in 76.3% of patients. The 1- and 2-year drug survival rates were 62% and 50%, respectively, with well-controlled disease activity as the most frequent reason for discontinuation in 69.2% of patients, followed by ineffectiveness in 23.1% and side effects in 7.7% of patients. CONCLUSIONS: This study demonstrates high safety and effectiveness of omalizumab treatment in pediatric patients with CU, which will aid clinical decision making and management of expectations when choosing omalizumab treatment for pediatric patients with CU.

Results of surgical treatment for renovascular hypertension in children: 30 year single centre experience.

BACKGROUND: We retrospectively reviewed the medical records of all patients who underwent surgery as part of the treatment of renovascular hypertension (RVH) at our centre between 1979 and 2008. Patients. Thirty-seven children (65% male) with a median age of 7.6 (0.4-17.9) years were identified with a median systolic blood pressure (SBP) of 140 (105-300) mm Hg prior to surgery. Bilateral renal artery stenosis and intra-renal disease were present in 19 (51%) patients, mid-aortic syndrome in 15 (40%), involvement of visceral arteries in eight out of 35 (23%) and coexisting cerebral disease in eight out of 30 (26%) investigated patients. RESULTS: Surgical procedures (n = 53) included (i) nephrectomy (18, of which two unplanned and two secondary due to technical failure), (ii) renovascular surgery on the renal arteries (28, of which 18 had autologous surgery and 10 synthetic grafts inserted for revascularisation) and (iii) aortic reconstruction with (6) and without (1) a synthetic graft. Post-operative complications were haemorrhage (5), septicaemia (5) and chylous ascites (1). There were no perioperative deaths; two children died during follow-up. The SBP post-surgery improved to a median value of 116 (range 90-160) mm Hg. Twelve months after surgery, 16 (43%) children had normal blood pressure without treatment, 15 (41%) normal or improved on one to four antihypertensive drugs and four (11%) unchanged; no data were available for two (5%) children. CONCLUSION: Surgery effectively treated the hypertension of 90% of our children, when performed in conjunction with medical therapy and interventional radiology. In spite of aggressive surgical treatment, RVH is sometimes a progressive disease.