Pathogenic G6PD variants: Different clinical pictures arise from different missense mutations in the same codon.

G6PD deficiency results from mutations in the X-linked G6PD gene. More than 200 variants are associated with enzyme deficiency: each one of them may either cause predisposition to haemolytic anaemia triggered by exogenous agents (class B variants), or may cause a chronic haemolytic disorder (class A variants). Genotype-phenotype correlations are subtle. We report a rare G6PD variant, discovered in a baby presenting with severe jaundice and haemolytic anaemia since birth: the mutation of this class A variant was found to be p.(Arg454Pro). Two variants affecting the same codon were already known: G6PD Union, p.(Arg454Cys), and G6PD Andalus, p.(Arg454His). Both these class B variants and our class A variant exhibit severe G6PD deficiency. By molecular dynamics simulations, we performed a comparative analysis of the three mutants and of the wild-type G6PD. We found that the tetrameric structure of the enzyme is not perturbed in any of the variants; instead, loss of the positively charged Arg residue causes marked variant-specific rearrangement of hydrogen bonds, and it influences interactions with the substrates G6P and NADP. These findings explain severe deficiency of enzyme activity and may account for p.(Arg454Pro) expressing a more severe clinical phenotype.

Pediatric idiopathic anaphylaxis: practical management from infants to adolescents.

Idiopathic anaphylaxis (IA) remains a frustrating challenge for both patients and physicians. The aim of this paper is to focus on IA in pediatric ages and suggest possible diagnostic algorithms according to specific age ranges (infants, children, and adolescents). In fact, in a variable percentage of patients, despite extensive diagnostic tests, the cause of anaphylactic episodes cannot be identified. Moreover, the lack of a unanimous IA definition requires a careful and detailed diagnostic workup. Prompt recognition of signs and symptoms, especially in younger children, and an accurate clinical history often allow a choice of the most appropriate diagnostic tests and a correct differential diagnosis.

Elimination Diets in Lactating Mothers of Infants with Food Allergy.

Breastfeeding is the most important nutrition source for infants. However, managing breastfed infants with signs and symptoms related to food allergy can be difficult. Many studies have shown the presence of different food allergens in breast milk, but the clinical role of these antigens in human milk is still much debated. Milk is the main suspect in exclusively breastfed infants with signs and symptoms attributable to food allergy, even if other foods may be responsible. This narrative review analyzes the recommendations provided by international guidelines to determine the diagnosis and management of IgE-mediated and non-IgE-mediated food allergies in exclusively breastfed infants. Dietary restrictions in lactating mothers of infants with suspected FA are usually not necessary. Only in the very few cases where significant allergy signs and symptoms occur in the infant during exclusive breastfeeding should the lactating mother follow an elimination diet for the suspected food for a short period.

Exercise-induced bronchoconstriction, allergy and sports in children.

Exercise-induced bronchoconstriction (EIB) is characterized by the narrowing of airways during or after physical activity, leading to symptoms such as wheezing, coughing, and shortness of breath. Distinguishing between EIB and exercise-induced asthma (EIA) is essential, given their divergent therapeutic and prognostic considerations. EIB has been increasingly recognized as a significant concern in pediatric athletes. Moreover, studies indicate a noteworthy prevalence of EIB in children with atopic predispositions, unveiling a potential link between allergic sensitivities and exercise-induced respiratory symptoms, underpinned by an inflammatory reaction caused by mechanical, environmental, and genetic factors. Holistic management of EIB in children necessitates a correct diagnosis and a combination of pharmacological and non-pharmacological interventions. This review delves into the latest evidence concerning EIB in the pediatric population, exploring its associations with atopy and sports, and emphasizing the appropriate diagnostic and therapeutic approaches by highlighting various clinical scenarios.

Imported allergens in Italy: an emerging issue.

Imported allergens are involved in many allergic reactions, with unexpected and unusual implications. They can be involved in developing asthma, allergic rhinoconjunctivitis, Hymenoptera venom allergies and food allergies. Imported allergens can be implied in respiratory allergies attributable to commercial practices and accidental diffusion through air currents that have introduced non-native species in new geographical contexts. Ambrosia artemisiifolia L., a plant native to North America and currently in the western part of Lombardy, represents an example. Moreover, a variation in the pollen concentration in the Northwest Tuscany area and Trentino Alto-Adige was observed. Cannabis sativa is another imported allergen used frequently by adolescents. Regarding potential imported food allergens, there is no validated list. Imported food allergens derive from ethnic foods, referring to Mexican/Latin American, Chinese/Japanese, Southeast Asian, Arab/Middle Eastern and African cuisine. Four insect flours were recently introduced to the European and Italian markets (Acheta domesticus, Alphitobius diaperinus, Tenebrio molitor and Locusta migratoria). The association between the accidental introduction through commercial traffic, climate change, and the absence of natural enemies in the destination ecosystem is related to the introduction of a specific Hymenoptera, Vespa velutina, in Italy and Europe. External events attributable to human activities, such as climate change and the introduction of non-native plants, foods and Hymenoptera through trade, have contributed to the issue of imported allergens. Making the correct diagnosis and guiding the diagnostic and therapeutic path in this particular context represent the concerns of the pediatric allergist.

Fatal food anaphylaxis in adults and children.

Anaphylaxis is a life-threatening reaction characterized by the acute onset of symptoms involving different organ systems and requiring immediate medical intervention. The incidence of fatal food anaphylaxis is 0.03 to 0.3 million/people/year. Most fatal food-induced anaphylaxis occurs in the second and third decades of life. The identified risk factors include the delayed use of epinephrine, the presence of asthma, the use of recreational drugs (alcohol, nicotine, cannabis, etc.), and an upright position. In the United Kingdom (UK) and Canada, the reported leading causal foods are peanuts and tree nuts. In Italy, milk seems to be the most common cause of fatal anaphylaxis in children < 18 years. Fatal food anaphylaxis in Italian children and adolescents almost always occurs outside and is characterized by cardiorespiratory arrest; auto-injectable adrenaline intramuscular was available in few cases. Mortality from food anaphylaxis, especially in children, is a very rare event with stable incidence, but its risk deeply impacts the quality of life of patients with food allergy and their families. Prevention of fatal food anaphylaxis must involve patients and their families, as well as the general public, public authorities, and patients' associations.

Personalization of Complementary Feeding in Children With Acute Food Protein-Induced Enterocolitis Syndrome.

Food protein-induced enterocolitis syndrome (FPIES) is a food allergy that results in repetitive vomiting, lethargy, and pallor within 1 to 4 hours of food ingestion. One of the issues in its management is the introduction of new foods. Over the past 25 years, suggestions have been made mainly based on the likelihood that a given food family could induce an episode of acute FPIES. Thus, foods have been categorized into low, moderate, and high risk. The suggestion was always to postpone the introduction of moderate- or high-risk foods, leaving the decision whether to introduce them at home or in hospital to the doctor. These suggestions were designed for all children with acute FPIES, regardless of their geographical area. However, it is true that these suggestions are the result of expert opinion. In recent years, studies have been published that have shown that the risk category of foods varies according to geographical area and so does the prevalence of single FPIES versus multiple FPIES. For this reason, we believe that the introduction of new foods in the child with acute FPIES can and should be tailored according to the geographical area.

Allergic Proctocolitis: Literature Review and Proposal of a Diagnostic-Therapeutic Algorithm.

Allergic proctocolitis (AP) is a benign condition, frequent in childhood, that is classified as a non-IgE-mediated food allergy. The prevalence is unknown; however, its frequency appears to be increasing, especially in exclusively breastfed infants. Clinical manifestations typically begin in the first few months of life with the appearance of bright red blood (hematochezia), with or without mucus, in the stool of apparently healthy, thriving infants. Most cases of AP are caused by cow's milk proteins; however, other allergens, such as soy, egg, corn, and wheat, may be potential triggers. Diagnosis is based on the patient's clinical history and on the resolution of signs and symptoms with the elimination of the suspected food antigen from the diet and their reappearance when the food is reintroduced into the diet. The treatment of AP is based on an elimination diet of the trigger food, with resolution of the symptoms within 72-96 h from the beginning of the diet. The prognosis of AP is good; it is a self-limiting condition, because most children can tolerate the trigger food within one year of life, with an excellent long-term prognosis. The purpose of this review is to provide an update on the current knowledge and recommendations in epidemiological, diagnostic, and therapeutic terms to the pediatricians, allergists, and gastroenterologists who may find themselves managing a patient with AP.

Latex Allergy in Children.

Notwithstanding the efforts made in the last decades to mitigate the consequences of natural rubber latex allergy, this disease continues to be a major health problem, especially in developing countries. The categories of patients with greater and frequent exposure to latex (such as health care professionals and, in the pediatric field, subjects who undergo repeated surgery, e.g., those suffering from spina bifida and urogenital malformations) have an increased risk of developing sensitization and allergy to latex. Herein we provide an overview of the current knowledge and practical recommendations with a focus on epidemiology, diagnostics, and management (including both prevention and therapy) in order to guide a correct recognition and containment of this potentially fatal condition.

Adherence to dietary prescriptions in patients with acute food protein-induced enterocolitis syndrome.

Food protein-induced enterocolitis syndrome (FPIES) is a non-Immunoglobulin (non-IgE)-mediated food allergy. The elimination diet is the only therapy, the culprit food will be reintroduced if tolerance is acquired. However, it is possible that patients do not follow the recommendations given by the healthcare professional. We investigated if our advice to avoid the trigger food in patients with active FPIES and to reintroduce it in the diet in patients who achieved tolerance had been implemented. We interviewed by telephone the parents of children who were diagnosed with acute FPIES. About 23.2% of our patients disregarded our dietary recommendations: 6/42 (14.3%) of patients who passed a tolerance oral food challenge (OFC) did not eat the trigger food, 4/22 (18.2%) of patients who failed OFC ate the trigger food, and 9/18 (50.0%) of patients who did not perform a tolerance OFC ate the trigger food. We have analyzed some possible influencing factors and no difference was found to be statistically significant. Our results are in line with those reported for IgE-mediated food allergies. As has already been proposed by others, we suggest reassessing food consumption in all patients after a food challenge.

Elective splenectomy in patients with non-Hodgkin lymphoma: Does the size of the spleen affect surgical outcomes?

Backgrounds/Aims: Splenectomy in patients with non-Hodgkin lymphoma (NHL) is performed to relieve abdominal symptoms, treat hypersplenism or confirm diagnosis. Excision of a very large spleen is technically challenging and data on outcomes of surgery in patients with NHL are scanty. The aim of study was to evaluate the impact of spleen size on the surgical outcome of splenectomy in patients with NHL. Methods: Patients with NHL who underwent splenectomy, between 2006 and 2017, were included and divided into two groups: group 1, spleen ≤ 20 cm; group 2, spleen > 20 cm. Surgical approach, operative time, postoperative morbidity, mortality, hospital stay and re-admission rates were retrospectively compared between groups. Non-parametric data were evaluated with the Mann-Whitney U test. Differences in frequencies were analyzed with Fisher's exact test. Results: Sixteen patients were included (group 1, 6; group 2, 10). Laparoscopy was successful in three patients of group 1, none of group 2 (p = 0.035), the intraoperative time did not differ significantly between groups. One patient in each group developed postoperative complications. The patient in group 1 died of pneumonia. Median length of stay was 8 days (range, 3-16 days) for group 1, 5.5 days (range, 3-10 days) for group 2, showing no significant difference between the two groups. No patient was readmitted to hospital. Conclusions: Spleen size does not affect the outcome of splenectomy in patients with NHL. If a mini-invasive approach is to be chosen, laparoscopy may not be feasible when the spleen size is > 20 cm.

Non-allergic benign infantile proctocolitis: a neglected nosographic entity.

The presence of rectal bleeding in the first months of life is very often diagnosed as food protein-induced allergic proctocolitis (FPIAP). The symptoms typically start in infancy, and most cases resolve by age 12 months. Infants with FPIAP usually present bloody stools mixed with mucus, with or without reduced stool consistency. Most affected infants are generally healthy-appearing. We used the story of an infant with rectal bleeding as a reminder that there is also the possibility of a form of benign non-allergic proctocolitis that is not usually included in the differential diagnosis. In the absence of warning signs and in case of infant well-being, it should be the first clinical entity to suspect. Therefore, we suggest we should wait at least 2 months before starting to eliminate cow milk or other foods from the diet.