Kawasaki disease and cardiac involvement: an update on the state of the art.

Kawasaki disease (KD) is an acute systemic vasculitis of unknown etiology. It has a self-limiting course and so far, represents the most common cause of coronary heart disease acquired in children aged between 6 months and 5 years. The inflammatory process can involve the coronary arteries with the formation of aneurysms and thrombotic occlusions with the risk of sudden death, especially in infants. Myocardial inflammation and abnormalities of cardiac contractility can occur acutely or many years after the disease onset. Therapy must be started within 10 days after the onset of symptoms to reduce the risk of heart complications. Immunoglobulin and aspirin treatment are effective in reducing heart complications. Recent studies have shown new therapeutic strategies (corticosteroids, immunosuppressive and biological drugs) in case of ineffectiveness of treatment with immunoglobulins.

ALMOND MILK: A POTENTIAL THERAPEUTIC WEAPON AGAINST COW’S MILK PROTEIN ALLERGY.

Food allergy is defined as an adverse health effect arising from a specific immune response that occurs reproducibly following exposure to a given food. Cow’s milk protein allergy results from an immunological reaction to one or more milk proteins. The principle key in the treatment of cow’s milk protein allergy is the dietary elimination of cow’s milk protein. Although hydrolyzed and elemental formulas are appropriate replacements, other milk products, including almond milk adequately integrated, could be administered. Here, in the light of encouraging results from our study, we focused on the anti-inflammatory and anti-oxidant properties of almond milk and we also believe that almond milk might be considered as a potential alternative in cow’s milk protein allergy treatment.

ATOPIC DERMATITIS: EXPRESSION OF IMMUNOLOGICAL IMBALANCE.

Atopic dermatitis is a chronic relapsing-remitting inflammatory skin condition, characterized by a skin barrier dysfunction resulting in epidermal damage and altered permeability to allergens and microbes. Although pathogenesis of atopic dermatitis is complex and still not fully understood, it has been hypothesized that genetic predisposition, environmental factors, and skin barrier dysfunction are involved. Innate and adaptive immune system has also a pivotal role in the development, maintenance and flare-up of atopic dermatitis. The immune-pathogenesis of atopic dermatitis is determined by the impairment of different T helper cells, of their cytokine secretion profiles as well as of their specific receptor. In this review, we focus on the current knowledge of the etiopathogenetic pathways of atopic dermatitis in relationship to the critical role of the innate and adaptive immune system, providing a unifying view.

HIGH-MOBILITY GROUP BOX 1 IN ALLERGIC AND NON ALLERGIC UPPER AIRWAY INFLAMMATION.

High mobility group box 1, an evolutionary ancient protein conserved in the eukaryotic kingdom, exerts intra- and extra- cellular functions, orchestrating a homeostatic defensive response in challenged tissues. Its action associated with various inflammatory cells is essential for the occurrence, progression, and persistence of asthma, rhinitis, and nasal polyposis. The recent discovery of High mobility group box 1, as a critical mediator of inflammation, stimulated an increasing interest in the field of inflammation research, suggesting new therapies for atopic and non-atopic inflammatory processes.

SUBLINGUAL IMMUNOTHERAPY IN CHILDREN: STATE OF ART.

Allergic immunotherapy (AIT) today represents a therapeutic practice for the treatment of allergic diseases such as rhinitis or asthma and is recognized as the only treatment able to modify the natural history of the disease. Administering gradually increasing doses of the causative allergen, AIT, has the objective of achieving immune tolerance against allergens. One of the administration routes most used in clinical practice is represented by the sublingual route. Current research on sublingual immunotherapy (SLIT) is focused on confirming the efficacy for all the different relevant allergens, on a better definition of allergen extracts and the improvement of their immunological properties and safety, on the identification of best treatment regimens, and on the possibility of extending the clinical indications. The aim of this review is to describe the most recent step in the field of SLIT development.

Nasal high-mobility group box-1 protein in children with allergic rhinitis.

BACKGROUND: Allergic rhinitis (AR) is characterized by an inflammatory reaction. High-mobility group box-1 protein (HMGB1) has many characteristics similar to classic proinflammatory cytokines. No study has yet investigated its role in AR. The aim of this study was to measure HMGB1 levels in the fluid recovered from nasal lavage in children with untreated AR and in control subjects. MATERIALS: The study was conducted on 104 AR subjects (48 males and 56 females, median age 10.3 ± 3.4 years) and 97 healthy children (42 males and 55 females) who were age-matched (median age 9.8 ± 4.1 years). Total serum immunoglobulin E, peripheral eosinophils and nasal symptoms assessed by visual analog scale (VAS) were considered. HMGB1 was measured using an ELISA assay. RESULTS: HMGB1 levels in nasal lavage fluid were higher in AR children than in the control group (96.9 ± 19.3 vs. 9.27 ± 4.01 ng/ml; p < 0.001). There was a very strong relationship between HMGB1 levels and VAS values in AR children (r = 0.919). Considering the symptom severity assessed by VAS, there was a relationship between HMGB1 and VAS in all AR subgroups: more evident in the severe subgroup (r = 0.727). CONCLUSIONS: Nasal HMGB1 has significantly increased in children with AR and is significantly related to symptom severity.

Impaired spirometry may suggest sensitization.

The present study confirms that sensitization is very frequent in the general population and suggests that impaired FEF25-75 may be a marker of sensitization. Therefore, when spirometry is abnormal, mainly concerning FEF25-75, sensitization should be suspected.

Effect of weight reduction on leptin, total ghrelin and obestatin concentrations in prepubertal children.

The aim of the study was to evaluate fasting levels of glucose, insulin, leptin, total ghrelin, and obestatin in a group of prepubescent obese children before and after weight loss. We enrolled 64 prepubescent obese children, but only 35 completed the study (mean age 7.6 +- 0.9 years, 19 females) and 20 normal-weight prepubescent children as controls. Fasting plasma concentration of glucose, insulin, Homeostasis Model assessment for insulin resistance (HOMA-IR), and leptin, total ghrelin, and obestatin levels were measured at baseline and after a 6-month lifestyle intervention (i.e. improved nutrition and increased physical activity). At baseline, obese children showed significantly (p less than 0.001) higher leptin and obestatin levels, and lower total ghrelin concentrations than control subjects. Weight loss significantly (p less than 0.001) diminished plasma leptin and insulin levels and increased ghrelin and obestatin concentrations. Weight loss in prepubescent children is associated with a significant change in leptin, ghrelin and obestatin concentrations. These results confirm the hypothesis that levels of these hormones are closely associated with obesity in childhood and might take part, as consequence but not as a cause, in glucose, fat, and energy metabolism.

Impaired FEF25-75 may predict high exhaled nitric oxide values in children with allergic rhinitis and/or asthma.

Allergic rhinitis and asthma are closely associated. Inflammation is a common pathological characteristic shared by both disorders. The measure of the fractional concentration of exhaled nitric oxide (FeNO) may be considered a surrogate marker for airway inflammation. Forced expiratory flow between 25 and 75 percent of vital capacity (FEF25-75) has been previously demonstrated to be able to predict BHR and bronchial reversibility. The aim of this study was to evaluate whether impaired FEF25-75 values may be related to FeNO values in a pediatric cohort of allergic subjects. 850 children with allergic rhinitis, allergic asthma, or both, were evaluated. Bronchial function (FEV1, FVC, and FEF25-75), FeNO, and sensitizations were assessed. Bronchial function and FeNO were significantly different in the 3 groups (p less than 0.001). A strong inverse correlation between FeNO and FEV1was found in patients with rhinitis, asthma and asthma with rhinitis (r= -0.72, r=-0.70 and r= -0.70, respectively). Impaired FEF25-75 values (such as less than 65 percent of predicted) were significantly associated with high FeNO levels (such as =34 ppb). In conclusion, this study provided evidence that FEF25-75 is strongly and inversely related with FeNO and FEF25-75 may predict high FeNO levels in children with allergic rhinitis, asthma or both.

Serum IL-23 in asthmatic children.

Asthma is characterized by airway inflammation that is controlled by a complex cytokine network. The Th1/Th2 imbalance has been well documented in the pathogenesis of allergic asthma. Recently, Th17 cells and regulatory T (Treg) cells have been found to participate in the pathogenesis of allergic asthma. This study aimed at verifying whether anti-inflammatory treatment could change serum IL-4, IL-10 and IL-23 in asthmatic children. Globally, 78 children (40 males and 38 females, median age 9.3 +- 3.7 years), with asthma and monosensitized to house dust mites, were evaluated. Lung function (such as FEV1) and serum IL-4, IL-10 and IL-23 levels were measured at baseline (T0), after 4 weeks (T1) and after 12 weeks (T2) of inhaled corticosteroid (ICS) treatment. The control group consisted of 40 healthy children (22 males and 18 females) age matched. At baseline, IL-4 and IL-23 levels were higher in severe asthmatics than in control group (p less than 0.001), while serum IL-10 levels were significantly lower in group of asthmatic children as compared to healthy control group (p less than 0.001). At T2, IL-4 and IL-23 significantly diminished (p less than 0.001), while IL-10 significantly increased. There was significant relationship between FEV1 and IL-4, IL-10 and IL-23 at T0 (r=-0.784; r=-0.735 and r=-0.787, respectively). Moreover, there were correlations between FEV1 and IL-4, IL-10 and IL-23 in patients at T1 (r=-0.563; r=-0.539 and r=-0.583, respectively) and at T2 (r=-0.549; r=-0.428 and r=-0.393, respectively). The present study provided evidence that: i) serum IL-23 was up-regulated also in asthmatic children, ii) ICS treatment was able of reducing IL-23, and iii) IL-23 change well related with lung function improvement. Thus, it is presumable that IL-23 could be a suitable marker of allergic inflammation in asthma.

Subclinic cardiac involvement in paediatric patients with celiac disease: a novel sign for a case finding approach.

The aim of the present work was to assess the prevalence of early cardiac involvement in children with celiac disease (CD), and the impact of a gluten free diet (GFD) on this issue. Sixty CD children was compared with a control group of 45 healthy children by an echocardiographic examination. CD patients were re-evaluated 1-year after 1-year GFD. Main outcome measures were ejection fraction (EF), fractional shortening (FS), left ventricular end-diastolic diameter (LVDD), left ventricular end-systolic diameter (LVSD), any regurgitating valve lesions. Mild cardiac involvement was found in 13 CD children and in one control (21.7% vs. 2.2%; p=0.003), and was secondary to regurgitation of mitral valve, aortic valve, pulmonary and tricuspid valve, or to impaired ejection fraction. CD children as compared to controls had significantly lower contractility indices, and higher left ventricular dimensions. In patients adhering to the GFD all valve regurgitations resolved, and the echocardiographic parameters significantly improved. Subclinical cardiac involvement in CD children is quite frequent, and GFD may exert a beneficial effect on the overall cardiac performance.

Mucosal immunity and sublingual immunotherapy in respiratory disorders.

The increasing prevalence of allergy and its impact on individual quality of life underline the need of an improvement of the treatment options in order to modify the natural course of allergic diseases. In this context, specific sublingual immunotherapy (SLIT) represents an approach currently available to redirect inappropriate immune response in atopic patients. The immunological mechanism that underlies SLIT has only started to be investigated. Oral mucosal tissue displays high permeability for allergens. It is conceivable that the sublingual administration route might induce immunological tolerance towards allergens involving cells and mediators specific of oral and intestinal mucosa. Recent literature data stated the presence in oral mucosa of dendritic cells (DCs) which express the high-affinity receptor for immunoglobulin (Ig)E (FcERI). Moreover some studies indicated that the mechanism of immunotherapy might be based on the increase of number and activity of regulatory T cells. Accumulating evidences suggest that the generation of T regulatory cells in periphery is orchestrated by a particular subset of DCs. It seems that repeated stimulation of naive CD4 T cells with allogenic immature DCs induce Tr1 cells maturation. Nevertheless other cells are involved in this process, such as TLR, MHC of I and II class and costimolatory molecules such as CD40, CD 80/B7.1 and CD 86/B7.2. An increase of serum IgG4 and IgA, a reduced number of inflammatory cells infiltrating target organs, as well as a reduction of eosinophilic cationic protein and a very heterogenous influence on T cells in the peripheral blood in terms of T cell suppression also occur with SLIT. All these molecules orchestrate the immune response within the regional immune system, recreating a favourite environment for the induction of tolerance operated by SLIT.

Pentraxin 3 in children suffering from allergic rhinitis.

Allergic disorders are typically characterized by an inflammatory response to allergen exposure. PTX3 behaves as an acute-phase response protein as there is a relationship between PTX3 plasma levels and disease severity. Therefore, this study was designed to investigate a possible role of PTX3 in children with allergic rhinitis. One hundred patients (28 females, 72 males, median age 11 years) were enrolled in the study. All patients were monosensitized: 43 (43%) to seasonal allergens (Graminaceae), 57 (57%) to perennial allergens (house dust mites, cat and dog epithelium, alternaria tenuis). Patients' blood samples for assessing serum PTX3 levels were performed during the spring. Children with rhinitis had higher PTX3 levels and there was a significant relationship between symptom severity and serum levels. Therefore, this study shows that PTX3 serum levels could be a reliable marker for symptom severity in children with allergic rhinitis.

Atopy as a risk factor for thyroid autoimmunity in children.

Recently, there has been considerable interest in the relationship between allergic and autoimmune diseases. We evaluated the prevalence of thyroid autoimmunity in 566 children affected by atopic dermatitis (AD), urticaria, rhinitis, chronic cough, and asthma. Our results suggest that allergy and autoimmunity can be two potential outcomes of dysregulated immunity. It is tempting to speculate that NK Th2 cells can favour asthma onset and at the same time improve thyroid autoimmunity.

A novel compound heterozygous TACI mutation in an autosomal recessive common variable immunodeficiency (CVID) family.

Common variable immunodeficiency (CVID) is a primary immune disorder characterized by low immunoglobulin serum levels and increased susceptibility to infections. Underlying genetic causes are only known in less than 15% of patients and encompass mutations in the genes encoding for ICOS, TACI, BAFF-R, CD19, CD20, CD81 and MSH5. TACI is the most frequently mutated gene among CVID patients. We report on two pediatric Italian male siblings with hypogammaglobulinemia and recurrent respiratory and gastrointestinal infections in association with a novel compound heterozygous TACI mutation. Both patients carry the I87N/C104R mutation that has not been reported yet. This results in aberrant TACI expression and abrogates APRIL binding on EBV B cells. This study identifies a novel combined mutation in TNFRSF13B increasing the spectrum of TACI mutations associated with CVID.