DAVID syndrome is a rare condition combining anterior pituitary hormone deficiency with common variable immunodeficiency. NFKB2 mutations have recently been identified in patients with ACTH and variable immunodeficiency. A similar mutation was previously found in Nfkb2 in the immunodeficient Lym1 mouse strain, but the effect of the mutation on endocrine function was not evaluated. We ascertained six unrelated DAVID syndrome families. We performed whole exome and traditional Sanger sequencing to search for causal genes. Lym1 mice were examined for endocrine developmental anomalies. Mutations in the NFKB2 gene were identified in three of our families through whole exome sequencing, and in a fourth by direct Sanger sequencing. De novo origin of the mutations could be demonstrated in three of the families. All mutations lie near the C-terminus of the protein-coding region, near signals required for processing of NFΚB2 protein by the alternative pathway. Two of the probands had anatomical pituitary anomalies, and one had growth and thyroid hormone as well as ACTH deficiency; these findings have not been previously reported. Two children of one of the probands carried the mutation and have to date exhibited only an immune phenotype. No mutations were found near the C-terminus of NFKB2 in the remaining two probands; whole exome sequencing has been performed for one of these. Lym1 mice, carrying a similar Nfkb2 C-terminal mutation, showed normal pituitary anatomy and expression of proopiomelanocortin (POMC). We confirm previous findings that mutations near the C-terminus of NFKB2 cause combined endocrine and immunodeficiencies. De novo status of the mutations was confirmed in all cases for which both parents were available. The mutations are consistent with a dominant gain-of-function effect, generating an unprocessed NFKB2 super-repressor protein. We expand the potential phenotype of such NFKB2 mutations to include additional pituitary hormone deficiencies as well as anatomical pituitary anomalies. The lack of an observable endocrine phenotype in Lym1 mice suggests that the endocrine component of DAVID syndrome is either not due to a direct role of NFKB pathways on pituitary development, or else that human and mouse pituitary development differ in its requirements for NFKB pathway function.

Prednisone (PDN) in juvenile dermatomyositis (JDM), alone or in association with other immunosuppressive drugs, namely methotrexate (MTX) and cyclosporine (CSA), represents the first-line treatment option for new onset JDM patients. No clear evidence based guidelines are actually available to standardize the tapering and discontinuation of glucocorticoids (GC) in JDM. Aim of our study was to provide an evidence-based proposal for GC tapering/discontinuation in new onset juvenile dermatomyositis (JDM), and to identify predictors of clinical remission and GC discontinuation. New onset JDM children were randomized to receive either PDN alone or in combination with methotrexate (MTX) or cyclosporine (CSA). In order to derive steroid tapering indications, PRINTO/ACR/EULAR JDM core set measures (CSM) and their median absolute and relative percent changes over time were compared in 3 groups. Group 1 included those in clinical remission who discontinued PDN, with no major therapeutic changes (MTC) (reference group) and was compared with those who did not achieve clinical remission, without or with MTC (Group 2 and 3, respectively). A logistic regression model identified predictors of clinical remission with PDN discontinuation. Based on the median change in the CSM of 30/139 children in Group 1, after 3 pulses of methyl-prednisolone, GC could be tapered from 2 to 1 mg/kg/day in the first two months from onset if any of the CSM decreased by 50–94%, and from 1 to 0.2 mg/kg/day in the following 4 months if any CSM further decreased by 8–68%, followed by discontinuation in the ensuing 18 months. The achievement of PRINTO JDM 50–70-90 response after 2 months of treatment (ORs range 4.5–6.9), an age at onset > 9 years (OR 4.6) and the combination therapy PDN + MTX (OR 3.6) increase the probability of achieving clinical remission (p < 0.05). This is the first evidence-based proposal for glucocorticoid tapering/discontinuation based on the change in JDM CSM of disease activity. Trial full title: Five-Year Single-Blind, Phase III Effectiveness Randomized Actively Controlled Clinical Trial in New Onset Juvenile Dermatomyositis: Prednisone versus Prednisone plus Cyclosporine A versus Prednisone plus Methotrexate. EUDRACT registration number: 2005–003956-37 . Clinical Trial.gov is NCT00323960 . Registered on 17 August 2005.

Background: Hereditary angioedema (HAE) in children has specific features and requires multidisciplinary management.Methods: We performed a literature search and underwent in‐depth discussions to provide practical tools for physicians.Results: HAE is a rare, life‐threatening genetic disorder. Its epidemiology is poorly documented in children. Clinical manifestations usually appear during childhood or early adolescence. Classical signs, often preceded by prodromal symptoms, include transient, localized, non‐pitting, non‐pruritic swelling of deep dermal/subcutaneous or mucosal/submucosal tissues, leading to oedema of the extremities, face, lips, tongue, trunk and genitals, recurring gastrointestinal symptoms and laryngeal edema possibly causing asphyxiation and death. Diagnosis is often delayed due to low awareness in the medical community, and particularly challenging in case of isolated abdominal crises or atypical presentation and in neonates or infants. It relies on biological tests (measurement of serum/plasma levels of C1INH function, C1INH protein, and C4), genetic testing in selected cases, and imaging for differential diagnosis of acute abdominal crises. Main differential diagnosis for peripheral oedema is mast cell‐mediated oedema that accounts for 95% of angioedema in clinical practice. Quality of life can be significantly impaired. Disease management includes treatment of attacks, short‐term and long‐term prophylaxis, psychological support, avoidance of triggers, patients’ and parents’ education and coordination of all stakeholders, ideally within a specialized healthcare network. New plasma kallikrein inhibitors, namely lanadelumab (subcutaneous route) and berotralstat (oral route) have facilitated long‐term prophylaxis thanks to improved usability.Conclusion: Diagnostic and treatment of HAE are particularly challenging in children and require specific management by multiple stakeholders.

Background: Relapses in pediatric high-risk brain tumors remain unmet medical needs. Over the last 15 years, metronomic chemotherapy has gradually emerged as an alternative therapeutic approach. Patients and Methods: This is a national retrospective study of patients with relapsing pediatric brain tumors treated according to the MEMMAT or MEMMAT-like regimen from 2010 to 2022. Treatment consisted of daily oral thalidomide, fenofibrate, and celecoxib, and alternating 21-day cycles of metronomic etoposide and cyclophosphamide associated with bevacizumab and intraventricular chemotherapy. Results: Forty-one patients were included. The most frequent malignancies were medulloblastoma (22) and ATRT (8). Overall, the best responses were CR in eight patients (20%), PR in three patients (7%), and SD in three patients (7%), for a clinical benefit rate of 34%. The median overall survival was 26 months (IC95% = 12.4–42.7), and median EFS was 9.7 months (IC95% = 6.0–18.6). The most frequent grade ¾ toxicities were hematological. Dose had to be adjusted in 27% of the cases. There was no statistical difference in outcome between full or modified MEMMAT. The best setting seems to be when MEMMAT is used as a maintenance and at first relapse. Conclusions: The metronomic MEMMAT combination can lead to sustained control of relapsed high-risk pediatric brain tumors.

Embryonal tumors with multilayered rosettes (ETMR) are rare embryonal tumors that usually affect children under two years old. They are characterized histo