Silvia Caimmi

Tryptase is the principal biomarker of mast cell (MC) burden and activation, routinely used in the diagnosis and management of MC-related disorders. Beyond its established role in confirming anaphylaxis, serum tryptase has gained increasing relevance in the diagnosis of systemic mastocytosis, hereditary α-tryptasemia (HαT), cutaneous mastocytosis, and selected haematologic diseases. Recent advances in MC biology, tryptase genetics, and disease classification have substantially improved the interpretation of baseline and acute (event-related) tryptase measurements. In particular, validation of the “20% + 2” consensus formula for MC activation and the recognition of HαT as a common genetic cause of elevated baseline serum tryptase have refined diagnostic algorithms and risk-stratification strategies. This review summarizes current knowledge on tryptase physiology, laboratory assessment, and clinical significance across multiple disease settings, with particular emphasis on the interpretation of baseline serum tryptase, the diagnostic role of tryptase in anaphylaxis and mastocytosis, and emerging applications in allergy, hematology, and chronic inflammatory disorders. Understanding both the strengths and limitations of serum tryptase measurement is essential for accurate diagnosis, prognostic assessment, and personalized patient management.

Current Allergen Immunotherapy (AIT) guidelines provide no definitive guidance on route selection, whether subcutaneous (SCIT) or sublingual (SLIT). The primary objective of this study was to characterize real-world AIT prescription patterns, with emphasis on route selection, using a factor analysis approach in a large international cohort. The CHOICE study is a real-life, multicentre, international, observational, cross-sectional web-based survey conducted across 20 countries between November 2019 and April 2024. Participating doctors completed standardized questionnaires for each consecutive AIT prescription. Thirteen patient-related and product-related parameters were analyzed using exploratory and confirmatory factor analysis. Latent factors identified were subsequently incorporated into multivariate mixed logistic regression models with country and physician nested within country as random intercepts. Data from 467 physicians and 11550 patients were analyzed; 60.0% of prescriptions were SCIT and 40.0% were SLIT. Three latent factors were identified: (F1) Scientific and clinical evidence-Based; (F2) Resource and access optimisation; and (F3) Tailored for the patient and their lifestyle. When country was modeled as a random intercept, all three factors were significantly associated with SLIT prescription. After adjustment for both country and physician, F2 was associated with reduced probability of SLIT prescription (OR 0.42; 95% CI 0.31, 0.59), while F3 was strongly associated with an increased probability of SLIT prescription (OR 10.90; 95% CI 7.20, 16.57). Variability attributable to country (ICC 0.86) and physician (ICC 0.74) was high. Patient-centred considerations increase the likelihood of SLIT use while considering the cost of the treatment increases the likelihood of SCIT use. Substantial variability in AIT route selection is attributable to country- and physician-level factors.

Background: Rome IV criteria promote a symptom-based (“positive”) diagnosis of pediatric disorders of gut–brain interaction (DGBIs). In clinical practice, however, organic gastrointestinal diseases may mimic DGBIs and lead to diagnostic revision after further evaluation. We aimed to quantify the diagnostic stability of an initial Rome IV-oriented functional diagnosis in a tertiary pediatric outpatient setting and to identify symptom phenotypes associated with a higher likelihood of later organic reclassification. Methods: We performed a single-center retrospective cohort study (2014–14 May 2021) based on outpatient chart review. Eligible patients were children and adolescents aged 0–18 years with an initial Rome IV-oriented functional diagnosis. Diagnostic reassessment was based on follow-up data, available laboratory and instrumental investigations, and/or response to exclusion therapies. Final diagnoses after reassessment were categorized as functional only, organic, or mixed. Groups were compared using Pearson’s chi-square test. Results: The cohort included 220 males (50.0%) and 220 females (50.0%), with a mean age of 8.86 ± 4.65 years. After reassessment, 343/440 (77.95%) remained functional, 73/440 (16.59%) were reclassified as organic, and 24/440 (5.45%) were classified as mixed. Final diagnosis differed by GI tract involvement (p = 0.001) and by symptom cluster (p = 0.001). Upper GI/dyspepsia-spectrum presentations showed the highest organic yield (27.03%), followed by lower abdominal pain/IBS-spectrum presentations (19.61%). Diarrhea and vomiting/cyclic vomiting each showed 16.67% organic diagnoses (mixed: 10.0% and 7.14%, respectively), whereas constipation showed the greatest diagnostic stability (98.89% functional; 1.11% organic). Functional confirmation rates were similar before and during the pandemic (77.71% vs. 78.70%; p = 0.756). Monthly case volume was higher in 2020–2021 (6.29 vs. 4.61 cases/month). Conclusions: In this tertiary cohort, about one in six children initially diagnosed with a functional disorder were later found to have an organic disease, and an additional 5% had mixed organic–functional presentations. Diagnostic revision was associated with presenting phenotype, with the highest organic yield observed in dyspepsia/upper GI presentations and the lowest in constipation. These findings support symptom-stratified evaluation and follow-up alongside Rome IV criteria.

Purpose: A multidisciplinary approach to Inflammatory Bowel Disease (IBD) has recently demonstrated a positive impact in pediatric patients, reducing dropout rates and facilitating the transition to adult care. Our study aims to evaluate how this approach influences disease activity, dropout rates, and transition. Methods: We conducted a longitudinal observational study including all patients diagnosed with IBD during pediatric-adolescent age, with a minimum follow-up period of 12 months. For each patient, endpoints included therapeutic approach, need for surgery and transition features. Results: We included 19 patients: 13 with Ulcerative Colitis (UC) and 6 with Crohn’s disease (CD). Most patients required multiple lines of therapy, with over 50% in both groups receiving biological drugs. Compliance was good, with a single dropout in each group (10, 5%). The need for surgery was significantly higher in the CD group compared to the UC group (16% vs. 7.7%, p < 0.01). Mean age at transition was significantly higher in the UC group compared to the CD group (19.2 ± 0.7 years SD vs. 18.3 ± 0.6 years SD, p < 0.05). Conclusions: In our experience, the multidisciplinary approach to IBD in transition-age patients appears effective in achieving clinical remission, offering the potential to reduce therapeutic dropouts.

Introduction: Artificial intelligence (AI) tools are increasingly being integrated into computer-aided diagnosis systems that can be applied to improve the recognition and clinical and molecular characterization of allergic diseases, including eosinophilic esophagitis (EoE). This review aims to systematically evaluate current applications of AI, machine learning (ML), and deep learning (DL) methods in EoE characterization and management. Methods: We conducted a systematic review using a registered protocol published in the International Prospective Register of Systematic Reviews (CRD42023451048). The risk of bias and applicability of eligible studies were assessed according to the prediction model study risk of bias assessment tool (PROBAST). We searched PubMed, Embase, and Web of Science to retrieve the articles. The literature review was performed in May 2023. We included original research articles (retrospective or prospective studies) published in English in peer-reviewed journals, studies whose participants were patients with EoE, and studies assessing the application of AI, ML, or DL models. Results: A total of 120 articles were found. After removing 68 duplicates, 52 articles were reviewed based on the title and abstract, and 34 were excluded. Eleven full texts were assessed for eligibility, met the inclusion criteria, and were analyzed for the systematic review. The AI models developed in three studies for identifying EoE based on endoscopic images showed high score performance with an accuracy that ranged from 0.92 to 0.97. Five studies developed AI models that histologically identified EoE with high accuracy (87% to 99%). We also found two studies where the AI model identified subgroups of patients according to their clinical and molecular features. Conclusions: AI technologies could promote more accurate evidence-based management of EoE by integrating the results of molecular signature, clinical, histology, and endoscopic features. However, the era of AI application in medicine is just beginning; therefore, further studies with model validation in the real-world environment are required.

Since October 2022, alerts have spread from several countries about the increase in invasive group A streptococcal (iGAS) and scarlet fever cases affecting young children. We aim to analyze the epidemiology of GAS infections in the last 12 years in our hospital and identify the clinical features of invasive cases observed in 2023. We conducted a retrospective study enrolling children and adolescents hospitalized at our pediatric clinic from January to December 2023 for a definitive diagnosis of iGAS infection. Clinical, laboratory, and imaging data were collected and analyzed. Comparing 2016 and 2023, we observed a similar number of GAS infections (65 vs. 60 cases). Five children with iGAS infection were hospitalized between March and April 2023. The median age was five years. At admission, all patients showed tachycardia disproportionate to their body temperature. Vomiting was a recurrent symptom (80%). Laboratory tests mostly showed lymphopenia, hyponatremia, and high inflammatory markers. The number of pediatric iGAS cases significantly increased in 2023. Clinical (pre-school-aged children with high fever, unexplained tachycardia, and vomiting) and laboratory parameters (high procalcitonin levels, hyponatremia, and lymphopenia) could help identify and suspect a potential iGAS infection.

Drug-induced anaphylaxis in children is less common than in adults and primarily involves beta-lactams and nonsteroidal anti-inflammatory drugs. Epidemiological studies show variable prevalence, influenced by age, gender, and atopic diseases. The pathophysiology includes IgE-mediated reactions and non-IgE mechanisms, like cytokine release reactions. We address drug-induced anaphylaxis in children, focusing on antibiotics, nonsteroidal anti-inflammatory drugs, neuromuscular blocking agents, and monoclonal antibodies. Diagnosis combines clinical criteria with in vitro, in vivo, and drug provocation tests. The immediate management of acute anaphylaxis primarily involves the use of adrenaline, coupled with long-term strategies, such as allergen avoidance and patient education. Desensitization protocols are crucial for children allergic to essential medications, particularly antibiotics and chemotherapy agents.

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.