CARD11 dominant negative mutation leads to altered human Natural Killer cell homeostasis.

Dominant negative mutations in CARD11 have been reported in patients with immune dysregulation, severe atopic features, and variable T cell alterations. Data on Natural killer (NK) cells from affected patients are lacking. We report on a 12-year-old boy with severe atopic dermatitis, food induced anaphylaxis and hypogammaglobulinemia harbouring a novel de novo heterozygous variant c.169G > A; p.Glu57Lys in CARD11. The dominant negative effect of this mutation was confirmed on both CD4+ and CD8+. CTLA4+Foxp3+CD4+ Tregs were severely reduced. Patient's NK cells showed reduced expression of NKp46, NKG2D and CD69. Patient's CD56bright NK cells showed in vitro impaired production of IFN-γ. Steady state pS6 levels on patient's NK cells were increased and remained elevated upon IL2 + IL12 + IL18 overnight stimulation. Overall, the effect of CARD11 mutation on mTORC1 differs between T and NK cells. These findings may explain the increased susceptibility to viral infections and the reduced immune surveillance in affected patients.

HMGB1: A pleiotropic activity.

High-mobility group box 1 (HMGB1) is a nuclear protein involved in DNA replication, transcription, recombination, and repair. In the extracellular space, the HMGB1 plays an essential role in the onset and perpetuation of inflammation, belonging to the group of damage-associated molecular pattern (DAMP) molecules, also called alarmins. For this, HMGB1 has been studied in several acute and chronic inflammatory diseases as an early biomarker of inflammation. An increased concentration of HMGB1 has been detected in serum, as the expression of systemic inflammation, and in specific samples (such as stool, synovial fluid, nasal lavage fluid, sputum, and cerebrospinal fluid), as the expression of local production, in several infectious and/or inflammatory diseases. These data are particularly important because they open new futuristic possibilities for target therapies, potentially also for the COVID-19 treatment.

Clinical and Laboratory Features of 184 Italian Pediatric Patients Affected with Selective IgA Deficiency (SIgAD): a Longitudinal Single-Center Study.

PURPOSE: Selective IgA deficiency (SIgAD) is the most common humoral primary immunodeficiency. Long-term follow-up data in large cohort of pediatric patients are scarce. METHODS: We report on a single-center cohort of 184 pediatric patients affected with selective IgA deficiency and describe the characteristics at diagnosis and during follow-up. RESULTS: Respiratory infections were the most common clinical finding leading to the initial diagnosis (62%). Positive family history for antibody deficiencies (selective IgA deficiency, common variable immunodeficiency) led to SIgAD diagnosis in 16% of cases. During follow-up, while the incidence of respiratory infections was not particularly high, gastrointestinal symptoms were reported in 27% of patients. Allergic manifestations were found in 23% at diagnosis and an additional 16% of patients during follow-up, leading to a prevalence of atopy of 39% among SIgAD patients. Autoimmune manifestations, excluding celiac disease, were found in 9% of affected patients during follow-up. Celiac disease was found in a high prevalence (14%). Increase of serum IgA levels to partial deficiency (9%) and normal serum levels for age (4%) was observed during follow-up. A small percentage of patients (2%) progressed to common variable immunodeficiency (CVID). CONCLUSIONS: In conclusion, this is the first study to describe a large single-center pediatric cohort of patients affected with SIgAD, revealing that overall most patients do well with regard to infections. Many develop CD, at a rate much higher than the general population. A few normalize their IgA levels. A few progress to CVID. Thus, careful follow-up is suggested to diagnose and treat potential complications earlier for avoiding potential morbidities.

Filaggrin mutations and Molluscum contagiosum skin infection in patients with atopic dermatitis.

BACKGROUND: Although mutations in the filaggrin (FLG) gene have been reported to predispose patients with atopic dermatitis (AD) skin infection susceptibility, to date, the data reported in the literature are still controversial. OBJECTIVE: To evaluate the role of FLG polymorphisms expression and risk of developing a concomitant Molluscum contagiosum sustained skin infection in the pediatric population with AD. METHODS: A total of 100 children with AD and 97 healthy children were enrolled. AD was diagnosed and assessed according to the validated European Task Force on Atopic Dermatitis. DNA samples of patients were analyzed for allelic variants in the promoter and coding exon of FLG. Genotyping was performed with polymerase chain reaction amplification and direct sequencing. RESULTS: Sixteen FLG variants have been detected in 29% of patients with AD: 2 synonymous (rs79808464 and rs116222149), 12 missense (rs11584340, rs113136594, rs145828067, rs374910442, rs747005144, rs145627745, rs144209313, rs74129443, rs192455877, rs150957860, rs138055273, rs147472105), 1 stop gained (rs183942200), and 1 frameshift (rs 558269137). In contrast, only 13% of the control group reported FLG mutations (22 heterozygous variants). In addition, the age at disease onset correlated significantly with FLG variants (P < .001). In addition, the AD with FLG gene variants (rs145627745, rs79808464, rs150957860, rs145828067, rs747005144, rs374910442, rs138055273, rs183942200, rs11584340, and rs113136594) reported moderate to severe Scoring Atopic Dermatitis scores. Finally, the AD group and the AD plus M contagiosum skin infection group had a significant association with FLG mutations when compared with the control group (P < .01). CONCLUSION: FLG mutations are associated with early onset of AD, more severe clinical course of disease, and a significantly increased risk of M contagiosum sustained skin infection.

High mobility group box 1: Biomarker of inhaled corticosteroid treatment response in children with moderate-severe asthma.

BACKGROUND: High mobility group box 1 (HMGB1) is abnormally expressed in serum and sputum of patients with allergic asthma. OBJECTIVE: The aim of this study was to investigate the role of HMGB1 as guidance for treatment management of children with asthma. METHODS: Thirty children with asthma and 44 healthy children were enrolled. The patients were classified according to Global Initiative for Asthma Guideline disease severity criteria. Sputum HMGB1 levels and lung function index (percentage forced expiratory volume in 1 second [FEV1%]) were recorded in the cohort study at baseline (T0) and after 3 (T3) and 6 (T6) months of inhaled corticosteroids (ICS) treatment. RESULTS: Sputum HMGB1 levels were significantly higher in all the patients with asthma (p < 0.001). An inverse correlation between sputum HMGB1 levels and pulmonary function parameters was observed only in the children with moderate asthma (T0: FEV1%, r = -0.9891, p < 0.001; T3: FEV1%, r = -0.6763, p < 0.001; T6: FEV1%, r = -0.5419, p < 0.05) and in the children with severe asthma (T0: FEV1%, r = -0.8696, p < 0.001; T3: FEV1%, r = -0.6477, p < 0.05; T6: FEV1%, r = -0.8627, p < 0.001). After ICS treatment, a significant decrease of sputum HMGB1 levels was noted in moderate (T0 [93.44 ± 20.65 ng/mL] versus T3 [77.96 ± 1.81 ng/mL] versus T6 [67.75 ± 3.01 ng/mL]; p < 0.0001) and in the children with severe asthma (T0 [130.3 ± 7.48 ng/mL] versus T3 [156.9 ± 1.09 ng/mL] versus T6 [116.08 ± 4.77 ng/mL]; p < 0.0001) data are mean ± standard deviation, respectively. The area under the receiver operating characteristic curve, performed to define the diagnostic profile of sputum HMGB1 levels in identifying the children with asthma, was 0.713. CONCLUSION: In addition to the findings that HMGB1 is a sensitive biomarker of allergic asthma in children, our data demonstrated a significant correlation between the decrease of HMGB1 levels and a successful treatment response.

A systematic review of food protein-induced enterocolitis syndrome from the last 40 years.

OBJECTIVE: To provide a complete, exhaustive summary of current literature relevant to food protein-induced enterocolitis syndrome (FPIES). DATA SOURCES: Data have been extracted from PubMed and Science Direct databases. STUDY SELECTIONS: Following the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines, a literature search for peer-reviewed journal articles in English through January 1975 with updates through October 2016 was conducted. Relevant publications were reviewed that included pediatric and adult populations. Information on the study design, sample, intervention, comparators, outcome, timeframe, and risk of bias were abstracted for each article. RESULTS: Of 135 reviewed reports, 52 were included in this systematic review. In accordance with the age at onset, clinical features, and offending foods, it is possible to distiguish different types of FPIES. An immune systemic involvement can occur in patients with FPIES. In addition to the most common causative foods (cow's milk, soy, and rice), any food can potentially cause FPIES. Although specific diagnostic tests are not available, open food challenge remains the gold standard for FPIES diagnosis. Moreover, because of the lack of randomized clinical trials and of use of different adopted methods, confounding factors might mask critical findings, leading to poor knowledge of this pleiotropic clinical entity. CONCLUSION: Multicenter studies are needed to better develop an evidence-based approach to pathophysiology, prevalence, diagnosis, and natural history of the disease.

Mode of delivery and atopic phenotypes: Old questions new insights? A retrospective study.

BACKGROUND: To date studies on the relation between mode of delivery and atopic diseases in are controversial. OBJECTIVE: The aim of the study was to determine a possible relationship between mode of delivery and risk of atopic phenotypes and, to assess the critical role of some pre-and post-natal parameters as a link between mode of delivery and risk of atopy. METHODS: 1516 children were assessed by skin prick tests, serum total and specific IgE levels. Parental reports on demographic and clinical data were also recorded. RESULTS: Of the 1516 children enrolled for the study, clinical and laboratory informations were obtained from 917 children. 460 children of them were born via CD and 457 via VD. Mode of delivery did not modify the prevalence of immune sensitization and/or allergic diseases. However, CD was associated with increased risk of atopy (p<0.001). Moreover, some parameters such as familiar history of atopy (p<0.001), habits smoking (p<0.05), exclusive artificial feeding (p<0.001); and breast-feeding time (<3months) (p<0.001) were associated with a major risk of atopy in CD group. Additionally, although our study confirmed that breast-feeding is associated to lower serum total IgE levels than artificial-feeding (p<0.001), it seems that the protective role of breast-feeding is negatively influenced from CD. Also in artificial-feeding subjects CD is related to a significant higher levels of IgE than VD (p<0.001). CONCLUSIONS: Our findings suggest that CD influences only the risk of atopy but no prevalence of immune sensitization and allergic diseases.

Mode of delivery and risk for development of atopic diseases in children.

Atopic diseases are a major public health problem worldwide, and several factors are thought to contribute to this rapid increase. The observed association between mode of delivery and risk of atopy in childhood has had a great deal of interest during the past few decades. In fact, even during delivery, exposure to antigens can index immune system in newborn, which induces the release of biologically active molecules, which are polarizing immune responses toward the T-helper 2 atopic profile. However, to date, studies on the relationship between mode of delivery and atopy have produced conflicting findings. The aim of this review was to summarize what is known about the relationship between mode of delivery and risk of atopic diseases in children. A literature search of electronic databases was undertaken for the major studies published from 1994 to today. The databases searched were PubMed, EMBASE, Medline, and Cochrane Library. The following key words were used: mode of delivery, cesarean section, vaginal delivery, atopy, and atopic diseases.

Serum interleukin 17, interleukin 23, and interleukin 10 values in children with atopic eczema/dermatitis syndrome (AEDS): association with clinical severity and phenotype.

To date cytokines profile in AEDS is poorly described in children. We evaluated the interleukin (IL)-17, IL-23, and IL-10 levels in atopic eczema/dermatitis syndrome (AEDS) children and healthy controls, in atopic AEDS (aAEDS) and nonatopic (naAEDS) subtypes and their relationship with disease severity. A total of 181 children with aAEDS and 93 healthy children were evaluated. According to the skin-prick test (SPT) for allergens and serum total IgE, all patients were subdivided in two groups: 104 aAEDS and 77 naAEDS. In all patients, serum IL-17, IL-23, and IL-10 levels were detected. Serum IL-17 and IL-23 levels were significantly higher, and serum IL-10 levels were significantly lower in AEDS children than healthy group (p < 0.001). Moreover, serum IL-17 and IL-23 levels were significantly higher in aAEDS than in naAEDS subtypes (p < 0.001). Differently, serum IL-10 levels resulted similar in both subtypes. There was a correlation between Score Atopic Dermatitis (SCORAD) index and both IL-17 and IL-23 and an inverse correlation between SCORAD index and IL-10 in aAEDS and naAEDS types. Serum IL-17 and IL-23 values were positively related to total IgE levels (p < 0.0001) in aAEDS. Further increase of IL-17 and IL-23 levels was detected in aAEDS subjects with atopic diseases such as asthma and rhinitis than children with only allergic sensitization. Our study confirms the role of IL-17, IL-23, and IL-10 and their relationship with the severity of AEDS. We firstly found a correlation between high IL-17/IL-23 axis levels and different phenotypes of AEDS in children, suggesting its role as marker of "atopic march" and disease severity.

Autoimmune liver disease in Noonan Syndrome.

Noonan Syndrome (NS) is characterized by short stature, typical facial dysmorphology and congenital heart defects. The incidence of NS is estimated to be between 1:1000 and 1:2500 live births. The syndrome is transmitted as an autosomal dominant trait. In approximately 50% of cases, the disease is caused by missense mutations in the PTPN11 gene on chromosome 12, resulting in a gain of function of the non-receptor protein tyrosine phosphatase SHP-2 protein. Autoimmune Hepatitis (AIH) is a cryptogenic, chronic and progressive necroinflammatory liver disease. Common features of AIH are hypergammaglobulinemia (IgG), presence of circulating autoantibodies, histological picture of interface hepatitis and response to immunosuppressant drugs. Conventional treatment with Prednisone and Azathioprine is effective in most patients. We describe the case of a 6 years-old girl with Noonan Syndrome and Autoimmune Hepatitis type 1. Molecular analysis of PTPN11 gene showed heterozygous mutation c.923A>G (Asn308Ser) in exon 8. Though association between NS and autoimmune disorders is known, this is the second case of association between Noonan Syndrome and Autoimmune Hepatitis type 1 described in literature. In the management of NS, an accurate clinical evaluation would be recommended. When there is a clinical suspicion of autoimmune phenomena, appropriate laboratory tests should be performed with the aim of clarifying whether the immune system is involved in NS. We think that autoimmunity represents a characteristic of NS, even if the etiopathogenesis is still unknown.

Expansion of CCR4+ activated T cells is associated with memory B cell reduction in DOCK8-deficient patients.

Hyper-IgE syndrome (HIES) is a genetic disorder characterized by elevated IgE serum levels, mostly due to mutations in STAT3 or DOCK8. Despite clinical heterogeneity between the two forms of the disease, clinical manifestations may not be conclusive for diagnosis and immunological differences are still unclear. Herein, we performed a detailed characterization of the T- and B-cell compartments by flow cytometry in seven HIES patients with homozygous DOCK8 mutations and six patients presenting heterozygous STAT3 mutations. We observed that DOCK8-deficient patients showed a marked reduction of naive and recent thymic emigrant (RTE) T lymphocytes together with a relative increase of activated T cells, most of which co-expressed the chemokine receptor CCR4, a marker of Th2 polarization. Moreover, an extreme reduction of memory B cells was detected, despite a normal/increased proportion of immunoglobulin-secreting cells. These observations indicate that DOCK8-deficient patients display a distinctive immunophenotype which is characteristic of this form of HIES.

Idiopathic intracranial hypertension: a unifying neuroendocrine hypothesis through the adrenal-brain axis.

The clinical syndrome idiopathic intracranial hypertension (IIH), also termed pseudotumor cerebri, consists of symptoms of headache, nausea, vomiting and visual field defects in combination with findings of papilledema. IIH is more commonly seen in overweight women where the rise in intracranial pressure is putatively a consequence of an endocrine-based disturbance of electrolytes. Less frequently, it can also occur in men and in the pediatric age group. Associated risk factors include primary and secondary aldosteronism, pregnancy, recombinant growth hormone (r-GH) therapy, oral contraceptives, obesity, vitamin A intoxication or deficiency, Addison disease, corticosteroid therapy or acute withdrawal of steroid therapy and Cushing disease. Herein, we review the association between these conditions and IIH working toward its having a unifying neuroendocrine hypothesis.

A forced expiratory flow at 25-75% value <65% of predicted should be considered abnormal: a real-world, cross-sectional study.

Forced expiratory volume in 1 second (FEV1) is considered an important parameter for asthma diagnosis and follow-up. However, it has been proposed that forced expiratory flow at 25-75% (FEF(25-75)) could be more sensitive than FEV1 to detect slight airways obstruction. In this regard, a cutoff FEF(25-75) value has been recently established in a group of asthmatic children: FEF(25-75) < 65% of predicted has been considered impaired. However, the considered population was specifically selected. Therefore, the aim of the present study was to confirm an FEF(25-75) cutoff value in a large cohort of asthmatic children. Seven hundred allergic children (493 male subjects; median age, 11 years) with controlled and partly controlled asthma were evaluated by performing spirometry and skin-prick tests. Three hundred thirteen (44.7%) patients had FEF(25-75%) values of <65% of predicted. Two predictors were significantly associated with impaired FEF(25-75) values: (i) sensitization to perennial allergens (adjusted odds ratio [OR(Adj)], 3.4) and (ii) FEV(1) ≤ 86% of predicted (OR(Adj), 3.8). This study, conducted in real life, could suggest that FEF(25-75) value of <65% of predicted may be considered abnormal.