Current state and advances in desensitization for peanut allergy in pediatric age.

Peanut allergy affects about 1%-3% of the pediatric population in the world, with an important increase in the last decades. Nowadays, international guidelines recommend the early introduction of peanuts in the infant diet, with poor information about the quantity and the frequency of the intake. Allergen immunotherapy may represent the only therapeutic strategy able to modify the natural history of peanut allergy. In particular, oral immunotherapy showed the most promising results in terms of efficacy, but with significant rates of adverse reactions, mostly gastrointestinal. In 2020, the Food and Drug Administration and the European Medicines Agency approved Palforzia®, an oral drug for patients aged 4-17 years. Several studies are ongoing to improve the tolerability of oral immunotherapy and standardize the desensitization protocols. Sublingual immunotherapy permits to offer much lower doses than oral immunotherapy, but fewer adverse events are shown. Subcutaneous immunotherapy is associated with the greatest systemic adverse effects. Epicutaneous immunotherapy, for which Viaskin® patch was approved, has the highest safety profile. Innovative studies are evaluating the use of biological drugs, such as omalizumab or dupilumab, and probiotics, such as Lactobacillus rhamnosus, in monotherapy or associated with oral immunotherapy. Therapy for peanut allergy is constantly evolving, and new perspectives are ongoing to develop.

Record of strep throat infections in Italy: what is needed to know about penicillin allergy? The point of view from the Italian Society of Pediatric Allergy and Immunology (SIAIP).

Notifications of invasive group A streptococcal (iGAS) infections have significantly increased in many European Countries compared to the previous season. In Italy, there has been an increase in streptococcal pharyngitis and scarlet fever cases since January 2023, which sparked concerns about a GAS epidemic in the pediatric population. This rise may be ascribed to the GAS infection season that began earlier than usual (off-season outbreak) and the increase in the spread of respiratory viruses and viral coinfections that raised the risk of iGAS disease. Moreover, this phenomenon was also facilitated by increased travel after reduced GAS circulation during the COVID-19 pandemic.The increase in cases of GAS disease has raised some critical issues regarding the potential reactions to administering amoxicillin, the first-line antibiotic therapy, many of which have been erroneously labeled as "allergy."For these reasons, the Italian Society of Pediatric Allergy and Immunology (SIAIP) intends to provide simple clinical indications to help pediatricians manage GAS pharyngitis, discerning the allergic from non-allergic drug hypersensitivity.

A Practical Update on Pediatric Eosinophilic Esophagitis.

Eosinophilic esophagitis (EoE) is an emerging atopic disease of unknown etiology limited to the esophagus. The pathogenesis is still understood and is likely characterized by type 2 inflammation. Food allergens are the primary triggers of EoE that stimulate inflammatory cells through an impaired esophageal barrier. In children and adolescents, clinical presentation varies with age and mainly includes food refusal, recurrent vomiting, failure to thrive, abdominal/epigastric pain, dysphagia, and food impaction. Upper-gastrointestinal endoscopy is the gold standard for diagnosing and monitoring EoE. EoE therapy aims to achieve clinical, endoscopic, and histological ("deep") remission; prevent esophageal fibrosis; and improve quality of life. In pediatrics, the cornerstones of therapy are proton pump inhibitors, topical steroids (swallowed fluticasone and viscous budesonide), and food elimination diets. In recent years, much progress has been made in understanding EoE pathogenesis, characterizing the clinical and molecular heterogeneity, and identifying new therapeutic approaches. Notably, clinical, molecular, endoscopic, and histological features reflect and influence the evolution of inflammation over time and the response to currently available treatments. Therefore, different EoE phenotypes and endotypes have recently been recognized. Dupilumab recently was approved by FDA and EMA as the first biological therapy for adolescents (≥12 years) and adults with active EoE, but other biologics are still under consideration. Due to its chronic course, EoE management requires long-term therapy, a multidisciplinary approach, and regular follow-ups.

Selective IgM Deficiency: Evidence, Controversies, and Gaps.

Selective Immunoglobulin M deficiency (SIgMD) has been recently included in the inborn errors of immunity (IEI) classification by the International Union of Immunological Societies Expert Committee. The understanding of SIgMD is still extremely limited, especially so in cases of SIgMD in the pediatric population. The epidemiology of SIgMD in the pediatric population is still unknown. The pathogenesis of SIgMD remains elusive, and thus far no genetic nor molecular basis has been clearly established as a definitive cause of this primary immunodeficiency. Recurrent respiratory infections represent the main clinical manifestations in children, followed by allergic and autoimmune diseases. No conclusive data on the correct therapeutic management of SIgMD are available. Although, for most SIgMD patients, Ig replacement therapy is not required, it may be recommended for patients with significantly associated antibody deficiency and recurrent or severe infections. Prophylactic antibiotics and the prompt treatment of febrile illness are crucial. There is insufficient evidence on the prognosis of this condition. Therefore, further studies are required to define the disease trajectories and to increase our understanding of the molecular mechanisms underlying SIgMD in order to facilitate a better clinical, immunological, and prognostic characterization of the condition and develop tailored therapeutic management strategies.

Clinical and immunological phenotypes of selective IgM deficiency in children: Results from a multicenter study.

BACKGROUND: A few studies assessed the clinical and immunological features of selective IgM deficiency (SIgMD), especially in the pediatric age. We aimed to characterize the clinical and immunological phenotypes of a cohort of pediatric patients with SIgMD according to the different diagnostic criteria available. METHODS: In this multicenter study, we evaluated pediatric SIgMD patients diagnosed at the Pediatric Clinic in Pavia, Italy, or through the Italian Primary Immunodeficiency NETwork (IPINET) and monitored changes in their diagnosis over a time frame that ranges from several months to several years. RESULTS: Forty-eight patients with SIgMD were included (mean serum IgM: 33 mg/dL). The most common clinical manifestations were recurrent infections (67%) and allergies (48%). Subgroup analysis according to SIgMD definition criteria of the European Society for Immunodeficiencies (ESID) showed no significant difference in clinical manifestations, also considering the group with additional immunological abnormalities. Sixteen patients had long-term follow-up, during which 87% preserved their SIgMD diagnosis, while two patients showed a reduction in IgA in addition to low IgM. CONCLUSIONS: Our data suggest that the identification of a reduction in serum IgM in children should lead to a complete immunological work-up to obtain a comprehensive clinical and immunological characterization of the patient. The follow-up of these patients is fundamental to define the disease evolution and appropriate management.

Severe pediatric asthma endotypes: current limits and future perspectives.

INTRODUCTION: Although rare, pediatric severe therapy-resistant asthma (STRA) is a highly heterogeneous, resource-demanding disease that differs significantly from severe adult asthma and whose pathogenesis is still poorly understood. AREAS COVERED: This review summarizes the latest 10 years of English-written studies defining pediatric STRA endotypes using lung-specific techniques such as bronchoalveolar lavage and endobronchial biopsy. Results of the studies and limits on the field are discussed, together with some future perspectives. EXPERT OPINION: Over the years, it has become increasingly clear that 'one size does not fit all" in asthma. However, "Does an extremely tailored size fit more than one?'. Only using multicentric, longitudinal pediatric studies, will we be able to answer. Three issues could be particularly critical for future research. First, to provide, if existing, a distinction between prepuberal STRA and puberal STRA endotypes to understand the transition from pediatric to adult STRA and to design effective, tailored therapies in adolescents, usually suffering from poorer asthma control. Second, design early treatments for pediatric airway remodeling to preserve lifelong good lung function. Finally, to better characterize inflammation before and during biological therapies, to provide clues on whether to stop or change treatments.

Food allergy: cause or consequence of pediatric eosinophilic esophagitis? Potential implications of ultraprocessed foods in prevention and management.

Eosinophilic esophagitis (EoE) is a chronic, immune-mediated disease characterized by eosinophilic infiltration, leading to esophageal dysfunction, inflammation, and fibrotic remodeling. In the last few decades, there has been an increased prevalence of EoE at an alarming rate in the pediatric age. The pathogenesis of EoE is still largely undefined, and this limits the definition of effective strategies for the prevention and management of this condition. EoE is considered a multifactorial disease arising from a negative interaction between environmental factors and genetic background, causing an impaired esophageal epithelial barrier with subsequent abnormal allergen exposure activating type 2 (Th2) inflammation. Food antigens have been suggested as key players in Th2 inflammation in pediatric patients with EoE, but emerging evidence suggests a potential role of other dietary factors, including ultraprocessed foods, as possible triggers for the occurrence of EoE. In this paper, we discuss the potential role of these dietary factors in the development of the disease, and we propose a new approach for the management of pediatric patients with EoE.

COVID-19 and autoimmune diseases: is there a connection?

PURPOSE OF REVIEW: This review summarizes current evidence on the potential link between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and autoimmunity. RECENT FINDINGS: Several viral infections are potential triggers of reactive and autoimmune diseases by inducing type II and type IV hypersensitivity reactions. Recent evidence demonstrated that SARS-CoV-2 infection is not an exception, triggering the production of tissue-specific autoantibodies during the acute phase of coronavirus disease 2019 (COVID-19) and leading to autoimmune diseases development as long-term complication. The significant immune dysregulation with cytokine storm and organ damage observed in patients with severe to critical COVID-19 is considered the main mechanism explaining the high levels of autoantibodies, which are also implicated in disease severity and the need for an intensive care assessment. Multisystem inflammatory syndrome in children (MIS-C) is an immune-mediated disease where the recent viral infection leads to systemic inflammation, as already observed in other reactive and autoimmune diseases. SUMMARY: Autoimmunity may be a complication of SAR-CoV-2 infection. Understanding the pathogenesis of autoimmune manifestations in COVID-19 might help prevent the incidence or exacerbation of autoimmune disorders and design better and more efficient treatment strategies in children and adult populations.

Evaluation of diagnostic time in pediatric patients with eosinophilic gastrointestinal disorders according to their clinical features.

Eosinophilic gastrointestinal disorders (EGIDs) are chronic/remittent inflammatory diseases associated with a substantial diagnostic delay, often attributable to misdiagnosis and variable clinical presentation in adults. In the pediatric population, few studies have been conducted worldwide reporting EGID diagnostic delay and its consequences on patients. This study aims to analyze and identify potential clinical factors and complications associated with a longer diagnostic time. We performed a retrospective analysis of pediatric patients with EGIDs followed at the Center for Pediatric EGIDs in Pavia, Italy. A total of 60 patients with EGIDs were enrolled. Thirty-nine (65%) patients had EoE, and 21 (35%) non-esophageal EGIDs. EGID diagnosis was achieved about 2 years after the symptom onset, and the median diagnostic time was 12 months (IQR 12-24 months). Diagnostic time was 12 months (IQR 12-69) in non-esophageal EGIDs and 12 months (IQR 4-24 months) in EoE patients. EoE patients presenting with FTT and feeding issues experienced a longer diagnostic time (p = 0.02 and p = 0.05, respectively) than children without growth and feeding impairments.In this study, symptoms appeared about 2 years before the definitive EGID diagnosis was reached, and this diagnostic time was shorter than the delay observed in other published studies. Especially in EoE children, the diagnostic time is significantly associated with impaired child growth, highlighting the importance of an early diagnosis to prevent esophageal stenosis and failure to thrive.

Eosinophilic Gastrointestinal Diseases in Inborn Errors of Immunity.

Inborn errors of immunity (IEI) are disorders mostly caused by mutations in genes involved in host defense and immune regulation. Different degrees of gastrointestinal (GI) involvement have been described in IEI, and for some IEI the GI manifestations represent the main and characteristic clinical feature. IEI also carry an increased risk for atopic manifestations. Eosinophilic gastrointestinal diseases (EGIDs) are emerging disorders characterized by a chronic/remittent and prevalent eosinophilic inflammation affecting the GI tract from the esophagus to the anus in the absence of secondary causes of intestinal eosinophilia. Data from the U.S. Immunodeficiency Network (USIDNET) reported that EGIDs are more commonly found in patients with IEI. Considering this element, it is reasonable to highlight the importance of an accurate differential diagnosis in patients with IEI associated with mucosal eosinophilia to avoid potential misdiagnosis. For this reason, we provide a potential algorithm to suspect an EGID in patients with IEI or an IEI in individuals with a diagnosis of primary EGID. The early diagnosis and detection of suspicious symptoms of both conditions are fundamental to prevent clinically relevant complications.

Omalizumab and allergen immunotherapy for respiratory allergies: A mini-review from the Allergen-Immunotherapy Committee of the Italian Society of Pediatric Allergy and Immunology (SIAIP).

Although currently approved to treat severe asthma and chronic spontaneous urticaria, omalizumab has also been an effective and safe add-on treatment for other allergic diseases. Namely, omalizumab has been proposed to be used as add-on therapy in patients with allergic rhinitis and asthma and undergoing specific allergen immunotherapy (AIT). AIT is the only treatment that modifies the natural history of IgE-mediated diseases. This brief review summarizes the available evidence and controversies on the efficacy and safety of omalizumab combined with specific AIT.

Pediatric Anaphylaxis: A 20-Year Retrospective Analysis.

BACKGROUND: Anaphylaxis is a steadily increasing global problem defined as an acute hypersensitivity multisystem reaction that is potentially fatal. In the pediatric age, the leading cause is food. In other allergic diseases, intrinsic heterogeneity has been reported in the clinical presentation, severity, and triggers of anaphylaxis. This study analyzes the features and management approach of the anaphylactic reactions in children evaluated at the pediatric clinic in Pavia. MATERIALS AND METHODS: A retrospective study was conducted on patients with anaphylaxis between 2001 and 2021. RESULTS: A total of 148 patients with a median age of 5 years were enrolled, and 80% of the patients had other atopic comorbidities that were correlated with the severity of anaphylaxis. The main trigger of anaphylaxis was food. Most reactions involved mucocutaneous, respiratory, and gastrointestinal systems, and occurred at home. Adrenaline was administered only in a minority of cases. CONCLUSIONS: Considering that anaphylaxis is a potentially life-threatening condition requiring prompt management, the use of adrenaline should be implemented. Our data also suggest the importance of educating and spreading awareness of anaphylactic management within the medical community.

Pediatric chronic spontaneous urticaria: a brief clinician's guide.

INTRODUCTION: Chronic urticaria (CU) appears with daily or intermittent/recurrent wheals with/without angioedema for more than six weeks. When no specific eliciting factors are found, chronic urticaria is defined as spontaneous (CSU). Up to 50% of patients with CSU do not respond to therapy, leading to a prolonged disease course and the need for expensive therapies, impacting the quality of life (QoL) and healthcare resources. AREAS COVERED: Diagnosis of CSU is made when other potential causes of chronic urticaria are excluded. CSU therapy aims to achieve complete control of symptoms and normalization of QoL. Current treatment options for urticaria aim to target mast cell mediators such as histamine, or activators, such as autoantibodies. Guidelines recommend starting with second generation antihistamines (sgAHs) and adding omalizumab therapy if symptoms are not controlled. This review aims to provide a practical guide for CSU in the pediatric population. EXPERT OPINION: Treatment options for pediatric CSU are primarily based on adult data that have been extrapolated for children. Current guidelines should be reevaluated based on pediatric data, new biological treatments, and the COVID-19 pandemic. Future research is needed to investigate strategies to personalize current treatments and identify potential predictive biomarkers.

Pediatric obesity: a mini-review for pediatrician.

Obesity is a multifactorial disease, and its prevalence in children has been increased over the last 30 years in Italy and many other European Countries. Obesity significantly impacts the quality of life of affected patients and health care systems. Obesity is related to several clinical comorbidities, especially metabolic syndrome and diabetes. The standard of care in this patient is still considered lifestyle changes and a healthy diet with regular physical activity to prevent associated metabolic complications (impaired glucose tolerance and type 2 diabetes) and reduce cardiovascular risk.Therefore, pediatricians should recognize potential risk factors (sedentary lifestyle, sugar, and fats-rich diet, genetic syndromes) and early signs of overweight and obesity to promptly address the child to a pediatric endocrinologist and a specialized reference Center.

Pseudohypoparathyroidism: a diagnosis to consider once a PTH elevation is detected.

BACKGROUND AND AIM: Pseudohypoparathyroidism (PHP) is a rare disease, which can occur in the youth, characterized by hypocalcemia and hyperphosphatemia due to resistance to parathyroid hormone (PTH) in target organs. This condition encompasses different conditions which differ between one another by different clinical, biochemically, and genetic features. METHODS: Herein we report the clinical history of a boy with PHP1B with an interesting clinical presentation. He came in fact to the attention of the Emergency Department because of a spontaneously resolving epileptic attack, lasting about 15 minutes, characterized by loss of consciousness, fall to the ground, tonic-clonic shocks, and sphincter release. Moreover, the personal history was characterized by congenital long QT syndrome (LQTS), with a documented mutation of the KCNQ1 gene, treated with beta-blockers (nadolol). RESULTS: The simultaneous presence of symptomatic acute hypocalcemia and long QT syndrome undoubtedly required particular attention both in the management of the onset and in the more in-depth subsequent diagnostics. In this regard, laboratory tests and molecular analyzes have proved to be crucial in the diagnostic process. Conclusions: this case underlines the diagnostic path complexity in patients with PTH elevation and the importance of considering all the possible differential diagnoses in order to undertake a timely and correct course of treatment.

Obesity and COVID-19 in children and adolescents: a double pandemic.

BACKGROUND AND AIM OF THE STUDY: The high prevalence of obesity and obesity-related comorbidities has reached pandemic proportions, particularly in Western countries. It has been recently recognized as a significant risk factor in severe cases of COVID-19 in children and adolescents. Here, we summarize the existing knowledge regarding the pathophysiology of COVID-19 and consider how its various components may be exacerbated by the presence of obesity to investigate the impact of obesity on disease severity among patients with COVID-19 and collaborate for better clinical care of these patients. METHODS: The literature search was conducted from March 2020 to January 2022. A review of articles was performed via the online database PubMed, combining the terms "obesity," "weight gain," "COVID-19", "children." RESULTS: Excessive adipose tissue, insulin resistance, dyslipidemia, hypertension, high levels of proinflammatory cytokines are factors that compromise the functioning of organs and systems in obese patients. In obese patients with COVID-19 these changes can increase the risk of death, need for ventilatory assistance, risk of thromboembolism, and perpetuation of inflammatory response. CONCLUSIONS: Obesity increases the risk for hospitalization, intensive care admission, mechanic ventilation requirement, and death among children and adolescents with COVID-19. These findings emphasize the need for effective actions by health professionals to increase awareness of the risks resulting from obesity and how these are heightened in the current global pandemic.