Dermatologic Effects of Selumetinib in Pediatric Patients with Neurofibromatosis Type 1: Clinical Challenges and Therapeutic Management.

Background: Plexiform neurofibromas (pNFs) are benign neoplasms, primarily originating from Schwann cells, posing challenges in patients with type 1 neurofibromatosis (NF1) due to pain, disfigurement, compression of vital structures and potential for malignancy. Selumetinib, a MEK1/2 inhibitor, has shown promising results in treating inoperable pNFs, with clinical trials demonstrating tumor volume reduction and improved patient-reported outcomes. Despite its efficacy, dermatologic toxicities may impact the quality of life and treatment adherence. Evaluating the frequency and spectrum of such effects is crucial for effective management. Methods: In a four-year retrospective and prospective study, pediatric NF1 patients with symptomatic, inoperable plexiform neurofibromas (pNFs) were treated with selumetinib. Eligibility criteria included significant morbidity, pNF size exceeding 3 cm or surgical inoperability, and performance status >70%. Hematological, liver, lung and cardiac assessments established baseline health. Selumetinib, orally administered at 25 mg/m2 twice, was administered for two years unless a response warranting extension occurred. Cutaneous AEs were documented and graded by severity according to CTCAE v5.0, with evaluations every three to six months. The impact on symptoms and pNF size was systematically recorded, and biopsies characterized histopathological features in those patients requiring surgery. Results: Twenty patients were enrolled, with an average age at therapy initiation of 11.6 years. Cutaneous side effects were common, with all patients experiencing at least one and a median of two per patient. Xerosis, paronychia and acneiform rash were prevalent. Notably, pre-pubertal individuals were more susceptible to xerosis. Acneiform rash had a higher incidence in older patients and those with skin phototypes II and III. Successful management involved tailored approaches, such as clindamycin for acneiform rash and topical agents for paronychia. Hair abnormalities, including color changes and thinning, occurred, with female patients at higher risk for the latter. Paronychia presented challenges, necessitating various interventions, including surgical approaches. AEs led to treatment suspension in 20% of patients, with tumor rebound observed in 75%. Conclusions: According to our experience, successful management of selumetinib-induced cutaneous AEs requires tailored strategies including surgery. AEs might indirectly determine pNF regrowth due to therapy suspension. We thus emphasize the pivotal role of addressing cutaneous reactions for effective selumetinib management in pediatric patients.

The real-life management of glucose homeostasis abnormalities in pediatric onco-hematological diseases: data from a national survey.

Glycemic abnormalities are a frequent finding in pediatric oncological patients, both during treatment and after its discontinuation. Moreover, impaired glucose tolerance (IGT), impaired fasting glycemia (IFG) and diabetes mellitus (DM) are not rarely diagnosed in non-oncological hematological diseases. To explore the current pediatric Italian approach to the diagnosis and the management of the glycemic alterations in this clinical setting and, thus, to identify and enforce current clinical needs, we submitted an online 23-items survey to all the Italian Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) centers, and surveys were descriptively analyzed. Thirty-nine AIEOP centers were involved in the study. In 2021, among 75278 children and adolescents affected by an oncological or a hematological disease, 1.2 and 0.65% developed DM, while IGT or IFG were widespread in 2.3 and 2.8%, respectively. The main causes of DM were the use of corticosteroids in patients with cancer and the iron overload in patients with thalassemia. Venous fasting plasma glycemia was the most used tool to detect glycemic abnormalities. The performance of oral glucose tolerance test (OGTT) was extremely limited, except when IFG occurred. Despite the diagnosis of DM, ∼45% of patients with cancer and 30% of patients with one hematological disease did not receive an appropriate treatment. In the other cases, insulin was the drug of first choice. Emerging technologies for diabetes care (glucose sensors and insulin pumps) are not largely used yet. The results of our study support the standardization of the care of the glycemic abnormalities during or after onco-hematologic diseases in the pediatric age. Despite the scarce data in pediatric literature, proper guidelines are needed.

Gut-microbiota in children and adolescents with obesity: inferred functional analysis and machine-learning algorithms to classify microorganisms.

The fecal microbiome of 55 obese children and adolescents (BMI-SDS 3.2 ± 0.7) and of 25 normal-weight subjects, matched both for age and sex (BMI-SDS - 0.3 ± 1.1) was analysed. Streptococcus, Acidaminococcus, Sutterella, Prevotella, Sutterella wadsworthensis, Streptococcus thermophilus, and Prevotella copri positively correlated with obesity. The inferred pathways strongly associated with obesity concern the biosynthesis pathways of tyrosine, phenylalanine, tryptophan and methionine pathways. Furthermore, polyamine biosynthesis virulence factors and pro-inflammatory lipopolysaccharide biosynthesis pathway showed higher abundances in obese samples, while the butanediol biosynthesis showed low abundance in obese subjects. Different taxa strongly linked with obesity have been related to an increased risk of multiple diseases involving metabolic pathways related to inflammation (polyamine and lipopolysaccharide biosynthesis). Cholesterol, LDL, and CRP positively correlated with specific clusters of microbial in obese patients. The Firmicutes/Bacteroidetes-ratio was lower in obese samples than in controls and differently from the literature we state that this ratio could not be a biomarker for obesity.

Clinical outcome of pediatric medulloblastoma patients with Li-Fraumeni syndrome.

BACKGROUND: The prognosis for Li-Fraumeni syndrome (LFS) patients with medulloblastoma (MB) is poor. Comprehensive clinical data for this patient group is lacking, challenging the development of novel therapeutic strategies. Here, we present clinical and molecular data on a retrospective cohort of pediatric LFS MB patients. METHODS: In this multinational, multicenter retrospective cohort study, LFS patients under 21 years with MB and class 5 or class 4 constitutional TP53 variants were included. TP53 mutation status, methylation subgroup, treatment, progression free- (PFS) and overall survival (OS), recurrence patterns, and incidence of subsequent neoplasms were evaluated. RESULTS: The study evaluated 47 LFS individuals diagnosed with MB, mainly classified as DNA methylation subgroup "SHH_3" (86%). The majority (74%) of constitutional TP53 variants represented missense variants. The 2- and 5-year (y-) PFS were 36% and 20%, and 2- and 5y-OS were 53% and 23%, respectively. Patients who received postoperative radiotherapy (RT) (2y-PFS: 44%, 2y-OS: 60%) or chemotherapy before RT (2y-PFS: 32%, 2y-OS: 48%) had significantly better clinical outcome then patients who were not treated with RT (2y-PFS: 0%, 2y-OS: 25%). Patients treated according to protocols including high-intensity chemotherapy and patients who received only maintenance-type chemotherapy showed similar outcomes (2y-PFS: 42% and 35%, 2y-OS: 68% and 53%, respectively). CONCLUSIONS: LFS MB patients have a dismal prognosis. In the presented cohort use of RT significantly increased survival rates, whereas chemotherapy intensity did not influence their clinical outcome. Prospective collection of clinical data and development of novel treatments are required to improve the outcome of LFS MB patients.

Case report: Revascularization failure in NF1-related moyamoya syndrome after selumetinib: A possible pathophysiological correlation?

Neurofibromatosis type 1 (NF1) is a neurocutaneous syndrome caused by pathogenic variants in the NF1 gene, encoding a multidomain inhibitor of Ras activity. Thus, NF1 is considered a RASopathy and drugs targeting the RAS/mitogen-activated protein kinase (MAPK) pathway, such as the MAP kinase (MEK) 1/2 inhibitor Selumetinib, are promising therapeutic options to treat NF1-associated tumors, especially plexiform neurofibromas and optic way gliomas. However, surgical treatment is often required for NF1-related cerebrovascular manifestations, such as moyamoya syndrome (MMS). We report a case of an 8-year-old patient receiving Selumetinib at the dose of 25 mg/m2 orally 2 times a day as a treatment for many plexiform neurofibromas. He suffered from two close strokes and brain MRI revealed a severe cerebral vasculopathy consistent with MMS, with marked stenosis of both the internal carotid arteries. A two-step surgical revascularization procedure was performed, consisting of a direct by-pass with an encephalo-mio-synangiosis (EMS) followed by encephalo-duro-arterio-synangiosis (EDAS). Surprisingly, despite the surgical technical success, follow-up MRI revealed lack of the expected revascularization. Selumetinib is a powerful therapeutic option in the treatment of severe NF1-related tumors. However, our findings suggest that this drug may interfere with cerebral neovascularization in patients with MMS requiring surgical revascularization. This is supported by the crucial role of the Vascular-Endothelial Growth Factor (VEGF), whose signaling pathway involve MAPK, as promoter of the neovascularization. Our observations suggest to adopt an imaging surveillance strategy to prevent unfavorable surgical outcome in patients with NF1-associated MMS receiving Selumetinib, and that priority should be given to surgical revascularization.

Loss of Neuron Navigator 2 Impairs Brain and Cerebellar Development.

Cerebellar hypoplasia and dysplasia encompass a group of clinically and genetically heterogeneous disorders frequently associated with neurodevelopmental impairment. The Neuron Navigator 2 (NAV2) gene (MIM: 607,026) encodes a member of the Neuron Navigator protein family, widely expressed within the central nervous system (CNS), and particularly abundant in the developing cerebellum. Evidence across different species supports a pivotal function of NAV2 in cytoskeletal dynamics and neurite outgrowth. Specifically, deficiency of Nav2 in mice leads to cerebellar hypoplasia with abnormal foliation due to impaired axonal outgrowth. However, little is known about the involvement of the NAV2 gene in human disease phenotypes. In this study, we identified a female affected with neurodevelopmental impairment and a complex brain and cardiac malformations in which clinical exome sequencing led to the identification of NAV2 biallelic truncating variants. Through protein expression analysis and cell migration assay in patient-derived fibroblasts, we provide evidence linking NAV2 deficiency to cellular migration deficits. In model organisms, the overall CNS histopathology of the Nav2 hypomorphic mouse revealed developmental anomalies including cerebellar hypoplasia and dysplasia, corpus callosum hypo-dysgenesis, and agenesis of the olfactory bulbs. Lastly, we show that the NAV2 ortholog in Drosophila, sickie (sick) is widely expressed in the fly brain, and sick mutants are mostly lethal with surviving escapers showing neurobehavioral phenotypes. In summary, our results unveil a novel human neurodevelopmental disorder due to genetic loss of NAV2, highlighting a critical conserved role of the NAV2 gene in brain and cerebellar development across species.

Hydranencephaly in CENPJ-related Seckel syndrome.

Pathogenic variants in CENPJ have been first identified in consanguineous Pakistani families with Hereditary Primary Microcephaly type 6 (MCPH6). In addition to primary microcephaly, the CENPJ-related phenotypic spectrum lately included also distinctive and peculiar 'bird-like' craniofacial dysmorphisms, intrauterine and/or postnatal growth retardation, and moderate to severe intellectual disability (ID). These features are also part of the clinical spectrum of Seckel syndrome (SCKL) a genetically heterogeneous neurodevelopmental condition caused by mutations in different genes involved in cell cycle progression. Among these, CENPJ is responsible for type 4 Seckel syndrome (SCKL4). The literature reports two individuals affected by SCKL4 suffering from seizures and other two individuals with other brain malformations in addition to microcephaly. However, neither epilepsy nor brain malformations are described in detail and genotype-phenotype information remains limited. We describe the first Caucasian affected with SCKL4 and harboring a novel, homozygous mutation in CENPJ. We detail the clinical and neuroradiological findings including structural focal epilepsy and a severe brain malformation (i.e., hydranencephaly) that was never associated with SCKL4 to date.

Early molecular diagnosis of BRAF status drives the neurosurgical management in BRAF V600E-mutant pediatric low-grade gliomas: a case report.

BACKGROUND: To date, this is the only report showing with close and consecutive magnetic resonance images the extremely rapid response of two types of pediatric low-grade gliomas (PLGG) to vemurafenib and its impact on the surgical approach. CASES PRESENTATION: We report two cases of symptomatic PLGG treated with vemurafenib, a BRAF inhibitor: in a 12-year-old girl it was used as first-line medical treatment, reducing the tumor by 45% within a month and stabilizing to 76% after a year; in a 3-year-old boy with no improvement after SIOP LGG 2004 Protocol, vemurafenib induced in only one week a 34% shrinkage and solved the hydrocephalus, avoiding surgical operation. DISCUSSION AND CONCLUSIONS: Our cases demonstrate how an early molecular diagnosis of BRAF mutations through the neurosurgical biopsy is essential to promptly start targeted therapies., whose effect can influence both therapeutic and surgical decisions, hopefully reducing the occurrence of second neurosurgery with associated risks of neurological sequelae.

Infectious diseases associated with pediatric type 1 diabetes mellitus: A narrative review.

Diabetes mellitus (DM) has been frequently associated with an impaired immune response against infectious agents, making affected patients at risk for more severe disease and sometimes causing worse outcomes. The recent COVID-19 pandemic has seriously affected patients with both diabetes, in particular those carrying comorbidities or with poor glycemic control. As regards pediatric diabetes mellitus, the availability of more accurate and technological tools for glycemic management and the improved markers of metabolic control might mitigate the negative impact of infections. Notably, good metabolic control of diabetes since its diagnosis reduces not only the risk of microangiopathic complications but also of impaired immune response to infectious diseases. Therefore, vaccinations are strongly recommended. Our paper aims to provide the most updated evidence regarding infectious diseases in type 1 pediatric DM.

Acute Neurological Presentation in Children With SARS-CoV-2 Infection.

Background: In the pediatric population, the knowledge of the acute presentation of SARS-CoV-2 infection is mainly limited to small series and case reports, particularly when dealing with neurological symptoms. We describe a large cohort of children with acute SARS-CoV-2 infection, focusing on the neurological manifestations and investigating correlations between disease severity and population demographics. Methods: Patients aged 0-18 years with a positive molecular swab were recruited between April 2020 and March 2021 from a tertiary Italian pediatric centre. Clinical data, imaging, and laboratory test results were retrieved from our local dataset and statistically analyzed. Results: A total of 237 patients with a median age of 3.2 years were eligible; thirty-two (13.5%) presented with neurological symptoms, including headache (65.6%), altered awareness (18.8%), ageusia/anosmia (12.5%), seizures (6.3%), and vertigo (6.3%), combined in 7 (21.9%) cases. Respiratory (59.5%) and gastrointestinal (25.3%) symptoms were the most common among the 205 (86.5%) patients without neurological involvement. Neurological symptoms did not significantly influence the severity of the triage access codes. Moreover, pre-existing medical conditions were not higher in the group with neurological manifestations. Overall, fifty-nine patients (25%, 14/59 with neurological symptoms) required treatment, being antibiotics, systemic steroids, and heparin those most prescribed. Conclusion: Our study supports the overall benign course of the SARS-CoV-2 infection in children. Neurological manifestations, except for headache, remain a rare presenting symptom, and disease severity seems unrelated to pre-existing medical conditions.

Dyslipidemia in Children Treated with a BRAF Inhibitor for Low-Grade Gliomas: A New Side Effect?

BRAF inhibitors, in recent years, have played a central role in the disease control of unresectable BRAF-mutated pediatric low-grade gliomas (LGGs). The aim of the study was to investigate the acute and long-term effects of vemurafenib on the lipid metabolism in children treated for an LGG. In our cohort, children treated with vemurafenib (n = 6) exhibited alterations in lipid metabolism a few weeks after starting, as was demonstrated after 1 month (n = 4) by the high plasma levels of the total cholesterol (TC = 221.5 ± 42.1 mg/dL), triglycerides (TG = 107.8 ± 44.4 mg/dL), and low-density lipoprotein (LDL = 139.5 ± 51.5 mg/dL). Despite dietary recommendations, the dyslipidemia persisted over time. The mean lipid levels of the TC (222.3 ± 34.7 mg/dL), TG (134.8 ± 83.6 mg/dL), and LDL (139.8 ± 46.9 mg/dL) were confirmed abnormal at the last follow-up (45 ± 27 months, n = 6). Vemurafenib could be associated with an increased risk of dyslipidemia. An accurate screening strategy in new clinical trials, and a multidisciplinary team, are required for the optimal management of unexpected adverse events, including dyslipidemia.

New Trends and Most Promising Therapeutic Strategies for Epilepsy Treatment.

Background: Despite the wide availability of novel anti-seizure medications (ASMs), 30% of patients with epilepsy retain persistent seizures with a significant burden in comorbidity and an increased risk of premature death. This review aims to discuss the therapeutic strategies, both pharmacological and non-, which are currently in the pipeline. Methods: PubMed, Scopus, and EMBASE databases were screened for experimental and clinical studies, meta-analysis, and structured reviews published between January 2018 and September 2021. The terms "epilepsy," "treatment" or "therapy," and "novel" were used to filter the results. Conclusions: The common feature linking all the novel therapeutic approaches is the spasmodic rush toward precision medicine, aiming at holistically evaluating patients, and treating them accordingly as a whole. Toward this goal, different forms of intervention may be embraced, starting from the choice of the most suitable drug according to the type of epilepsy of an individual or expected adverse effects, to the outstanding field of gene therapy. Moreover, innovative insights come from in-vitro and in-vivo studies on the role of inflammation and stem cells in the brain. Further studies on both efficacy and safety are needed, with the challenge to mature evidence into reliable assets, ameliorating the symptoms of patients, and answering the challenges of this disease.

Urinary Tract Involvement in Wolfram Syndrome: A Narrative Review.

Wolfram Syndrome (WS) is a rare neurodegenerative disease with autosomal recessive inheritance and characterized by juvenile onset, non-autoimmune diabetes mellitus and later followed by optic atrophy leading to blindness, diabetes insipidus, hearing loss, and other neurological and endocrine dysfunctions. A wide spectrum of neurodegenerative abnormalities affecting the central nervous system has been described. Among these complications, neurogenic bladder and urodynamic abnormalities also deserve attention. Urinary tract dysfunctions (UTD) up to end stage renal disease are a life-threatening complication of WS patients. Notably, end stage renal disease is reported as one of the most common causes of death among WS patients. UTD have been also reported in affected adolescents. Involvement of the urinary tract occurs in about 90% of affected patients, at a median age of 20 years and with peaks at 13, 21 and 33 years. The aim of our narrative review was to provide an overview of the most important papers regarding urological impairment in Wolfram Syndrome. A comprehensive search on PubMed including Wolfram Syndrome and one or more of the following terms: chronic renal failure, bladder dysfunction, urological aspects, and urinary tract dysfunction, was done. The exclusion criteria were studies not written in English and not including urinary tract dysfunction deep evaluation and description. Studies mentioning general urologic abnormalities without deep description and/or follow-up were not considered. Due to the rarity of the condition, we considered not only papers including pediatric patients, but also papers with pediatric and adult case reports.

Prominent and Regressive Brain Developmental Disorders Associated with Nance-Horan Syndrome.

Nance-Horan syndrome (NHS) is a rare X-linked developmental disorder caused mainly by loss of function variants in the NHS gene. NHS is characterized by congenital cataracts, dental anomalies, and distinctive facial features, and a proportion of the affected individuals also present intellectual disability and congenital cardiopathies. Despite identification of at least 40 distinct hemizygous variants leading to NHS, genotype-phenotype correlations remain largely elusive. In this study, we describe a Sicilian family affected with congenital cataracts and dental anomalies and diagnosed with NHS by whole-exome sequencing (WES). The affected boy from this family presented a late regression of cognitive, motor, language, and adaptive skills, as well as broad behavioral anomalies. Furthermore, brain imaging showed corpus callosum anomalies and periventricular leukoencephalopathy. We expand the phenotypic and mutational NHS spectrum and review potential disease mechanisms underlying the central neurological anomalies and the potential neurodevelopmental features associated with NHS.

Complex Neurological Phenotype Associated with a De Novo DHDDS Mutation in a Boy with Intellectual Disability, Refractory Epilepsy, and Movement Disorder.

Mutations in the DHDDS gene (MIM: 617836), encoding a subunit of dehydrodolichyl diphosphate synthase complex, have been recently implicated in very rare neurodevelopmental diseases. In total, five individuals carrying two de novo mutations in DHDDS have been reported so far, but genotype-phenotype correlations remain elusive. We reported a boy with a de novo mutation in DHDDS (NM_205861.3: c.G632A; p.Arg211Gln) featuring a complex neurological phenotype, including mild intellectual disability, impaired speech, complex hyperkinetic movements, and refractory epilepsy. We defined the electroclinical and movement disorder phenotype associated with the monoallelic form of the DHDDS -related neurodevelopmental disease and possible underlying dominant-negative mechanisms.

Neuromuscular and Neuroendocrinological Features Associated With ZC4H2-Related Arthrogryposis Multiplex Congenita in a Sicilian Family: A Case Report.

Wieacker-Wolff syndrome (WWS) is an X-linked Arthrogryposis Multiplex Congenita (AMC) disorder associated with broad neurodevelopmental impairment. The genetic basis of WWS lies in hemizygous pathogenic variants in ZC4H2, encoding a C4H2 type zinc-finger nuclear factor abundantly expressed in the developing human brain. The main clinical features described in WWS families carrying ZC4H2 pathogenic variants encompass having a short stature, microcephaly, birth respiratory distress, arthrogryposis, hypotonia, distal muscle weakness, and broad neurodevelopmental delay. We hereby report a Sicilian family with a boy clinically diagnosed with WWS and genetically investigated with exome sequencing (ES), leading to the identification of a c.593G>A (p. R198Q) hemizygous pathogenic variant in the ZC4H2 gene. During the first year of life, the onset of central hypoadrenalism led to recurrent hypoglycemic events, which likely contributed to seizure susceptibility. Also, muscle biopsy studies confirmed a pathology of the muscle tissue and revealed peculiar abnormalities of the neuromuscular junction. In conclusion, we expand the phenotypic spectrum of the WWS-related neurodevelopmental disorders and discuss the role of ZC4H2 in the context of the potential neuroendocrinological and neuromuscular features associated with this condition.

Update on the Classification and Pathophysiological Mechanisms of Pediatric Cardiorenal Syndromes.

Cardiorenal syndrome (CRS) is defined as a disorder resulting from the abnormal interaction between the heart and kidney, in which acute or chronic dysfunction of one organ may lead to acute and/or chronic dysfunction of the other. The functional interplay between the heart and kidney is characterized by a complex bidirectional symbiotic interaction, regulated by a wide array of both genetic and environmental mechanisms. There are at least five known subtypes of CRS, based on the severity of clinical features and the degree of heart/renal failure. The fourth subtype (cardiorenal syndrome type 4 (CRS4)) is characterized by a primary chronic kidney disease (CKD), which in turn leads to a decreased cardiac function. Impairment of renal function is among the most important pathophysiological factors contributing to heart failure (HF) in the pediatric age group, and cardiovascular complications could be one of the most important causes of mortality in pediatric patients with advanced CKD. In this context, a loss of glomerular filtration rate directly correlates with both the progression of cardiovascular complications in CRS and the risk of HF. This review describes the interaction pathways between the heart and kidney and the recently identified pathophysiological mechanisms underlying pediatric CRS, with a special focus on CRS4, which encompasses both primary CKD and cardiovascular disease (CVD).

Genotype-Phenotype Correlations in Neurofibromatosis Type 1: A Single-Center Cohort Study.

Neurofibromatosis type 1 (NF1) is a proteiform genetic condition caused by pathogenic variants in NF1 and characterized by a heterogeneous phenotypic presentation. Relevant genotype-phenotype correlations have recently emerged, but only few pertinent studies are available. We retrospectively reviewed clinical, instrumental, and genetic data from a cohort of 583 individuals meeting at least 1 diagnostic National Institutes of Health (NIH) criterion for NF1. Of these, 365 subjects fulfilled ≥2 NIH criteria, including 235 pediatric patients. Genetic testing was performed through cDNA-based sequencing, Next Generation Sequencing (NGS), and Multiplex Ligation-dependent Probe Amplification (MLPA). Uni- and multivariate statistical analysis was used to investigate genotype-phenotype correlations. Among patients fulfilling ≥ 2 NIH criteria, causative single nucleotide variants (SNVs) and copy number variations (CNVs) were detected in 267/365 (73.2%) and 20/365 (5.5%) cases. Missense variants negatively correlated with neurofibromas (p = 0.005). Skeletal abnormalities were associated with whole gene deletions (p = 0.05) and frameshift variants (p = 0.006). The c.3721C>T; p.(R1241*) variant positively correlated with structural brain alterations (p = 0.031), whereas Lisch nodules (p = 0.05) and endocrinological disorders (p = 0.043) were associated with the c.6855C>A; p.(Y2285*) variant. We identified novel NF1 genotype-phenotype correlations and provided an overview of known associations, supporting their potential relevance in the implementation of patient management.