Vitamin D deficiency is associated with diagnosis and severity of childhood atopic dermatitis

Treatment of allergic children - Where is the progress (for the practicing allergist)?

For any kind of therapeutic intervention in allergic diseases such as environmental control, pharmacological, or immunomodulating treatment including educational programs, children are addressed separately from adults. Health authorities like the Food and Drug Administration in the United States of America or the European Medicine Agency in Europe request a specific 'Pediatric investigational plan' with studies addressing dose-response relationship, safety, and efficacy for infants, children, and adolescents. During the last 2 years, promising advances have been reported for the treatment of a variety of allergic and immunologic disorders. This review summarizes the progress in the treatment of pediatric asthma and allergic diseases, based on publications of approximately the last 2.5 years (end of 2013 until May 2016) in and beyond this journal. Meanwhile, it highlights areas with promising novel therapeutic approaches, which are likely to change treatment for allergic children in the near future.

Diet and eczema: a review of dietary supplements for the treatment of atopic dermatitis

In the context of increasing popularity of "natural" alternatives to conventional medicine, several dietary supplements have gained the attention of researchers and consumers alike in the treatment of atopic dermatitis (AD). Readily available without a prescription and frequently perceived to have fewer side effects than traditional medications, these "natural" remedies may be featured in discussions with patients, and clinicians should therefore be familiar with their efficacy and safety. Based on trials to date, no dietary supplements can be recommended for routine use in the treatment of AD. However, some promising results have been noted from the use of probiotics and prebiotics taken in combination. Given significant differences in study design to date, however, further studies would be needed to clarify dose and strains of probiotics. Studies of vitamin D have been limited and have produced conflicting results, although further trials in selected subsets of patients may be indicated. Very limited data is available on fish oil supplements, while future studies on Chinese herbal medicine would require evaluation of comparable herbs and formulations. Finally, multiple trials of evening primrose oil and borage seed oil have shown improvement similar to placebo, and neither is currently recommended in eczema therapy.

Diet and eczema: a review of dietary supplements for the treatment of atopic dermatitis

In the context of increasing popularity of "natural" alternatives to conventional medicine, several dietary supplements have gained the attention of researchers and consumers alike in the treatment of atopic dermatitis (AD). Readily available without a prescription and frequently perceived to have fewer side effects than traditional medications, these "natural" remedies may be featured in discussions with patients, and clinicians should therefore be familiar with their efficacy and safety. Based on trials to date, no dietary supplements can be recommended for routine use in the treatment of AD. However, some promising results have been noted from the use of probiotics and prebiotics taken in combination. Given significant differences in study design to date, however, further studies would be needed to clarify dose and strains of probiotics. Studies of vitamin D have been limited and have produced conflicting results, although further trials in selected subsets of patients may be indicated. Very limited data is available on fish oil supplements, while future studies on Chinese herbal medicine would require evaluation of comparable herbs and formulations. Finally, multiple trials of evening primrose oil and borage seed oil have shown improvement similar to placebo, and neither is currently recommended in eczema therapy.

The Relationship between Vitamin D Status and Allergic Diseases in New Zealand Preschool Children

Recent research on vitamin D in young children has expanded from bone development to exploring immunomodulatory effects. Our aim was to investigate the relationship of vitamin D status and allergic diseases in preschool-aged children in New Zealand. Dried capillary blood spots were collected from 1329 children during late-winter to early-spring for 25(OH)D measurement by LC-MS/MS. Caregivers completed a questionnaire about their child's recent medical history. Analysis was by multivariable logistic regression. Mean 25(OH)D concentration was 52(SD19) nmol/L, with 7% of children <25 nmol/L and 49% <50 nmol/L. Children with 25(OH)D concentrations ≥75 nmol/L (n = 29) had a two-fold increased risk for parent-report of doctor-diagnosed food allergy compared to children with 25(OH)D 50-74.9 nmol/L (OR = 2.21, 1.33-3.68, p = 0.002). No associations were present between 25(OH)D concentration and presence of parent-reported eczema, allergic rhinoconjunctivitis or atopic asthma. Vitamin D deficiency was not associated with several allergic diseases in these New Zealand preschool children. In contrast, high 25(OH)D concentrations were associated with a two-fold increased risk of parental-report food allergy. This increase supports further research into the association between vitamin D status and allergic disease in preschool children.

Scoping systematic review of treatments for eczema

Background

Eczema is a very common chronic inflammatory skin condition.

Objectives

To update the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) systematic review of treatments for atopic eczema, published in 2000, and to inform health-care professionals, commissioners and patients about key treatment developments and research gaps.

Data sources

Electronic databases including MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Skin Group Specialised Register, Latin American and Caribbean Health Sciences Literature (LILACS), Allied and Complementary Medicine Database (AMED) and Cumulative Index to Nursing and Allied Health Literature (CINAHL) were searched from the end of 2000 to 31 August 2013. Retrieved articles were used to identify further randomised controlled trials (RCTs).

Review methods

Studies were filtered according to inclusion criteria and agreed by consensus in cases of uncertainty. Abstracts were excluded and non-English-language papers were screened by international colleagues and data were extracted. Only RCTs of treatments for eczema were included, as other forms of evidence are associated with higher risks of bias. Inclusion criteria for studies included availability of data relevant to the therapeutic management of eczema; mention of randomisation; comparison of two or more treatments; and prospective data collection. Participants of all ages were included. Eczema diagnosis was determined by a clinician or according to published diagnostic criteria. The risk of bias was assessed using the Cochrane Collaboration risk-of-bias tool. We used a standardised approach to summarising the data and the assessment of risk of bias and we made a clear distinction between what the studies found and our own interpretation of study findings.

Results

Of 7198 references screened, 287 new trials were identified spanning 92 treatments. Trial reporting was generally poor (randomisation method: 2% high, 36% low, 62% unclear risk of bias; allocation concealment: 3% high, 15% low, 82% unclear risk of bias; blinding of the intervention: 15% high, 28% low, 57% unclear risk of bias). Only 22 (8%) trials were considered to be at low risk of bias for all three criteria. There was reasonable evidence of benefit for the topical medications tacrolimus, pimecrolimus and various corticosteroids (with tacrolimus superior to pimecrolimus and corticosteroids) for both treatment and flare prevention; oral ciclosporin; oral azathioprine; narrow band ultraviolet B (UVB) light; Atopiclair™ and education. There was reasonable evidence to suggest no clinically useful benefit for twice-daily compared with once-daily topical corticosteroids; corticosteroids containing antibiotics for non-infected eczema; probiotics; evening primrose and borage oil; ion-exchange water softeners; protease inhibitor SRD441 (Serentis Ltd); furfuryl palmitate in emollient; cipamfylline cream; andMycobacterium vaccaevaccine. Additional research evidence is needed for emollients, bath additives, antibacterials, specialist clothing and complementary and alternative therapies. There was no RCT evidence for topical corticosteroid dilution, impregnated bandages, soap avoidance, bathing frequency or allergy testing.

Limitations

The large scope of the review coupled with the heterogeneity of outcomes precluded formal meta-analyses. Our conclusions are still limited by a profusion of small, poorly reported studies.

Conclusions

Although the evidence base of RCTs has increased considerably since the last NIHR HTA systematic review, the field is still severely hampered by poor design and reporting problems including failure to register trials and declare primary outcomes, small sample size, short follow-up duration and poor reporting of risk of bias. Key areas for further research identified by the review include the optimum use of emollients, bathing frequency, wash products, allergy testing and antiseptic treatments. Perhaps the greatest benefit identified is the use of twice weekly anti-inflammatory treatment to maintain disease remission. More studies need to be conducted in a primary care setting where most people with eczema are seen in the UK. Future studies need to use the same core set of outcomes that capture patient symptoms, clinical signs, quality of life and the chronic nature of the disease.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

The role of vitamin D in atopic dermatitis

Vitamin D has been suggested to have an important impact on a much wider aspects on human health than calcium homeostasis and mineral metabolism, specifically in the field of human immunology. It has been reported that vitamin D influences the regulation of both innate and adaptive immune systems, which makes the association between vitamin D and allergic diseases a field of interest. Although many studies have sought to determine whether vitamin D has an influence on progression of allergic disease, the impact of vitamin D on atopic dermatitis development and severity remains unclear. In this review, we summarize recent studies relating vitamin D to atopic dermatitis and discuss its possible role in the pathogenesis of allergic skin diseases, emphasizing the need for well-designed, prospective trials on vitamin D supplementation in the context of prevention and treatment for allergic conditions.

Vitamin D in atopic dermatitis, chronic urticaria and allergic contact dermatitis

Vitamin D influences allergen-induced pathways in the innate and adaptive immune system, and its potential immunomodulatory role in allergic skin disorders has been explored. This comprehensive review article provides an overview of the role of vitamin D in three common dermatologic conditions: atopic dermatitis (AD), chronic urticaria, and allergic contact dermatitis (ACD). Whereas the literature regarding vitamin D and AD has resulted in mixed findings, several studies have described an inverse relationship between vitamin D levels and AD severity, and improvement in AD with vitamin D supplementation. Similarly, several studies report an inverse relationship between vitamin D levels and severity of chronic urticaria. Although current research in humans remains limited, an increased likelihood of ACD has been demonstrated in vitamin D-deficient mice. Additional well-designed clinical trials will be necessary to determine whether vitamin D supplementation should be recommended for prevention or adjuvant treatment of these common dermatologic conditions.

Predicting eczema severity beyond childhood

BACKGROUND

We evaluated factors associated with eczema severity in adolescence.

METHODS

Nottingham Eczema Severity Score (NESS), family and personal history of atopy, skin prick test for common food and aeroallergens, highest serum IgE level and eosinophil count were evaluated. Patients with paired NESSs (childhood-NESS is NESS performed at <10 years of age; adolescence-NESS is NESS performed at age >10 years) were further analyzed.

RESULTS

Adolescence-NESS (n=383 patients) was associated with eczema onset in infancy, dust mite and food allergen sensitization, dietary avoidance, use of wet wrap, traditional Chinese medicine, immunomodulant (azathioprine or cyclosporine), high IgE level, eosinophil count, but not with family/personal history of atopy. Eighty-two patients had both childhood-NESS and adolescence-NESS (mean follow-up of 6.8 years) showing that adolescence-NESS was associated with childhood- NESS severity grades (P=0.034). Of these patients, 48% remained in the same severity grades, whereas 39% improved, and 13% deteriorated from childhood to adolescence.

CONCLUSIONS

It is not possible to assure parents that their child can outgrow eczema. In eczema prognosis research, long-term follow-up is warranted.

Epidemiology of pediatric allergic diseases in the Ogasawara Islands

BACKGROUND

The Ogasawara Islands, away from mainland Japan, belong to a subtropical area. Although the daily eating habits and food are relatively similar to that on the mainland, the living environment is quite different. The prevalence of allergic diseases in the Ogasawara Islands is unknown. This study aimed to identify the prevalence of allergic diseases in the Ogasawara Islands.

METHODS

A survey was conducted among all children belonging to preschool, elementary school, and junior high school in the Ogasawara Islands. A questionnaire was prepared in accordance with the International Study of Asthma and Allergies in Childhood (ISAAC) core written questionnaire in bronchial asthma (BA) and the West Japan Study of Asthma and Allergies in Childhood core written questionnaire for atopic dermatitis (AD), allergic rhinitis (AR), and food allergy (FA). At the same time, height, weight, duration of dwelling on the island, home environment, lifestyle, and exercise habits were also asked.

RESULTS

The target population comprised 352 children, of whom 284 (80.6%) completed the questionnaires. The current prevalence was 9.3% for BA, 4.3% for AD, 17.8% for AR, and 3.0% for FA. Significantly lower rates of current BA and AD were observed compared to previous reports from Japan. The percentage of children belonging to sports clubs, and exercising more than 3 times per week at the Ogasawara Islands is higher compared with the national average.

CONCLUSIONS

The lower prevalence of BA and AD in the Ogasawara Islands implies the influence of differences in the living environment and exercise habits.

Serum 25-hydroxyvitamin D3 levels in children with allergic or nonallergic rhinitis

OBJECTIVES

The relationship between vitamin D and allergic diseases such as asthma and atopic dermatitis is shown in several studies. But there is a lack of knowledge about vitamin D status in children with allergic rhinitis (AR). We aimed to investigate serum vitamin D levels of children with AR or nonallergic rhinitis (NAR), to compare with normal subjects and to evaluate the relationship between vitamin D and the severity of AR.

METHODS

The study included a total of 141 children (76 patients with rhinitis and 65 control subjects), who applied to the Pediatric allergy immunology outpatient. Skin prick tests were performed using the same antigens for all patients. Serum 25-hydroxyvitamin D3 (25OHD3) levels were measured. AR was classified according to the ARIA guidelines.

RESULTS

Mean 25OHD3 levels were 18.07±6.1ng/mL in the AR group, 14.81±4.86 in the NAR, and 24.03±9.43ng/mL in the control group. These differences among groups were statistically significant (p=0.001). Vitamin D status was determined as deficient in 32 (66.7%) patients, insufficient in 14 (29.2%) and normal in 2 (4.2%) of the AR group. These frequencies for NAR and control groups are 25 (89.3%), 3 (10.7%), 0, and 25 (38.5%), 32 (49.2%), 8 (12.3%), respectively. Vitamin D status was found to be different among groups (p=0.001). There were not any association between 25OHD3 levels and allergen sensitivity (p>0.05). The comparison of the mean 25OHD3 levels according to the severity and duration of AR did not detect statistically significant difference among groups (respectively, p=0.384, p=0.23 Denburg J, Fokkens WJ, Togias A5).

CONCLUSIONS

The mean serum 25OHD3 levels of the children both with AR and NAR were lower than control group. No association between 25OHD3 levels and allergen sensitivities was found in our study. We did not find any relationship between 25OHD3 levels and the severity and duration of allergic rhinitis.

Effects of Pre-Natal Vitamin D Supplementation with Partial Correction of Vitamin D Deficiency on Early Life Healthcare Utilisation: A Randomised Controlled Trial

Background

Some observational studies have suggested that higher prenatal Vitamin D intake may be associated with improved health outcomes in childhood. However there have been mixed results in this area with some negative studies, especially for effects on atopic and respiratory outcomes. We examined the effect of prenatal Vitamin D on healthcare utilisation in the first three years of life.

Methods

In an ethnically stratified randomised controlled trial conducted at St Mary’s Hospital London, 180 women at 27 weeks gestation were allocated to no Vitamin D, 800 IU ergocalciferol daily until delivery, or a single oral bolus of 200,000 IU cholecalciferol. Participants were randomised in blocks of 15 using computer-generated numbers and investigators were blinded to group assignment. Supplementation increased maternal and cord blood 25(OH) vitamin D concentrations, but levels remained lower than current recommendations. Primary health economic outcome was overall cost of unscheduled healthcare utilisation in the first three years of life as documented in the child’s electronic health record. Secondary outcomes included cost attributable to: primary and secondary healthcare visits, respiratory and atopic complaints, cost in years 1, 2 and 3 of life and cost and frequency of prescribed medication. All costs were calculated as pounds sterling. Differences between groups were analysed using unpaired t-test or Mann-Whitney U test, and analysis of variance for adjusted analyses.

Results

We assessed 99/180 (55%) complete electronic health records, control (n = 31), daily (n = 36) and bolus (n = 32). We found no difference in total healthcare utilisation costs between the control and daily (mean difference in costs in pounds sterling 1.02, 95%CI -1.60, 1.65; adjusted 1.07, 95%CI -1.62, 1.86) or control and bolus groups (mean difference -1.58, 95%CI -2.63, 1.06; adjusted –1.40, 95%CI -2.45, 1.24). There were no adverse effects of supplementation reported during the trial.

Conclusions

We found no evidence that prenatal vitamin D supplementation from 27 weeks gestation to delivery, at doses which failed to completely correct maternal vitamin D deficiency, influence overall healthcare utilisation in children in the first 3 years.

Trial Registration

Controlled-Trials.com ISRCTN68645785

Systemic Agents for Severe Atopic Dermatitis in Children

Atopic dermatitis (AD), or eczema, is a chronic inflammatory skin condition characterized by relapsing pruritic, scaly, erythematous papules and plaques frequently associated with superinfection. The lifelong prevalence of AD is over 20 % in affluent countries. When a child with severe AD is not responding to optimized topical therapy including phototherapy, and relevant triggers cannot be identified or avoided, systemic therapy should be considered. If studies show early aggressive intervention can prevent one from advancing along the atopic march, and relevant triggers such as food allergies cannot be either identified or avoided, systemic therapy may also play a prophylactic role. Though the majority of evidence exists in adult populations, four systemic non-specific immunosuppressive or immunomodulatory drugs have demonstrated efficacy in AD and are used in most patients requiring this level of intervention regardless of age: cyclosporine, mycophenolate mofetil, methotrexate, and azathioprine. This article reviews the use of these medications as well as several promising targeted therapies currently in development including dupilumab and apremilast. We briefly cover several other systemic interventions that have been studied in children with atopic dermatitis.

Tear and serum vitamin D levels in children with allergic rhinoconjunctivitis

BACKGROUND

Although solid cohort studies confirmed a preventative role for the anti-oxidant vitamin D in allergic asthma, a limited number of studies focused on allergic rhinoconjunctivitis (ARC). Here, we aimed to determine 25-hydroxycholecalciferol levels in tear and serum in young allergic rhinoconjunctivitis patients as compared to their apparently healthy matched controls.

METHODS

In total, 22 children with allergic rhinoconjunctivitis and 31 healthy control subjects underwent serum total IgE and 25-hydroxycholecalciferol measurements. Tear levels of 25-hydroxycholecalciferol were also determined in both groups.

RESULTS

The mean serum total IgE level in the ARC group (143.6±132.8IU/ml) was significantly higher than that in the control group (54.8±44.1IU/ml; p=0.03). Serum 25(OH)D levels were significantly higher in the ARC group (34.1±12.7ng/ml) than in the healthy controls (21.8±11.3ng/ml; p=0.001).

CONCLUSIONS

To our knowledge, this is the first reported study to show an association between serum 25-hydroxycholecalciferol and ARC in a childhood group. Higher levels of serum 25-hydroxycholecalciferol in children with allergic rhinoconjunctivitis may indicate a possible aetiopathogenic mechanism in the development of allergic rhinoconjunctivitis. This is also the first report to examine tear fluid vitamin D levels in paediatric ARC patients.

No association between vitamin D and atopy, asthma, lung function or atopic dermatitis: a prospective study in adults

Studies suggest that vitamin D may be involved in the pathogenesis of allergic disorders, asthma and decreased lung function. However, results are inconsistent and only few prospective studies have examined adults. The purpose of this study was to investigate the association of serum 25-hydroxy vitamin D (s25(OH)D) with atopy, atopic dermatitis (AD), asthma, wheezing and impaired lung function in a prospective study of Danish adults. A random sample of 3471 persons was examined in 2006-2008. Of these, 2308 were re-examined 5 years later. s25(OH)D and specific IgE against four common inhalant allergens were measured by standard procedures. Wheezing, asthma and AD were assessed from questionnaires and lung function was measured by spirometry. We found no statistically significant associations between s25(OH)D and prevalence or incidence of atopy, AD, asthma or wheezing. Associations with lung function were inconsistent. We conclude that vitamin D status does not influence these conditions in adults.

Association between vitamin D levels and allergy-related outcomes vary by race and other factors

BACKGROUND

Allergy-related studies that include biological measurements of vitamin D preceding well-measured outcomes are needed.

OBJECTIVE

We sought to examine the associations between early-life vitamin D levels and the development of allergy-related outcomes in the racially diverse Wayne County Health, Environment, Allergy, and Asthma Longitudinal Study birth cohort.

METHODS

25-Hydroxyvitamin D (25[OH]D) levels were measured in stored blood samples from pregnancy, cord blood, and age 2 years. Logistic regression models were used to calculate odds ratios (ORs) with 95% CIs for a 5 ng/mL increase in 25(OH)D levels for the following outcomes at age 2 years: eczema, skin prick tests (SPTs), increased allergen-specific IgE level (≥ 0.35 IU/mL), and doctor's diagnosis of asthma (3-6 years).

RESULTS

Prenatal 25(OH)D levels were inversely associated with eczema (OR, 0.85; 95% CI, 0.75-0.96). The association was stronger in white children (white children: OR, 0.79; 95% CI, 0.57-1.09; black children: OR, 0.96; 95% CI, 0.82-1.12), although this was not statistically significant. Cord blood 25(OH)D levels were inversely associated with having 1 or more positive SPT responses and aeroallergen sensitization. Both associations were statistically significant in white children (positive SPT response: OR, 0.50; 95% CI, 0.32-0.80; ≥ 1 aeroallergen sensitization: OR, 0.50; 95% CI, 0.28-0.92) in contrast with black children (positive SPT response: OR, 0.88; 95% CI, 0.68-1.14; ≥ 1 aeroallergen sensitization: OR, 0.85; 95% CI, 0.65-1.11). 25(OH)D levels measured concurrently with outcome assessment were inversely associated with aeroallergen sensitization (OR, 0.79; 95% CI, 0.66-0.96) only among black children (white children: OR, 1.21; 95% CI, 0.87-1.69).

CONCLUSIONS

Prenatal and cord blood 25(OH)D levels were associated with some allergy-related outcomes, with a general pattern indicating that children with higher 25(OH)D levels tend to have fewer allergy-related outcomes.

Higher cord blood 25-hydroxyvitamin D concentrations reduce the risk of early childhood eczema: in children with a family history of allergic disease

Background

In recent years the role of vitamin D status in early life on the development of allergic disease has generated much interest. The aim of this study was to determine whether cord blood vitamin D concentrations were associated with risk of early childhood allergic disease.

Methods

Measurements of cord blood 25-hydroxyvitamin D [25(OH)D] concentrations were available in 270 mother-child pairs who were participating in the allergy follow-up (n = 706) of the Docosahexaenoic Acid to Optimise Mother Infant Outcome randomised controlled trial. All of the children had a hereditary risk of allergic disease. The diagnosis of allergic disease was made during medical assessments at 1 and 3 years of age.

Results

The mean (standard deviation) standardised cord blood 25(OH)D concentration was 57.0 (24.1) nmol/L. The cumulative incidence of eczema to 3 years of age, n = 101/250 (40 %) was associated with standardised cord blood 25(OH)D concentration, with a 10 nmol/L rise in 25(OH)D concentration reducing the risk of eczema by 8 % (relative risk 0.92, 95 % confidence interval 0.86–0.97; P = 0.005). This association was stronger at 1 year of age, when a 10 nmol/L rise in standardised cord blood 25(OH)D concentration reduced the risk of eczema by 12 % (relative risk 0.88, 95 % confidence interval 0.81–0.96; P = 0.002). No associations between cord blood 25(OH)D concentrations and development of allergic sensitisation, allergic rhinitis or asthma in early childhood were found.

Conclusion

In children with a family history of allergic disease, a higher cord blood 25(OH)D concentration appears to be associated with reduced risk of eczema in early childhood.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12610000735055 (DOMInO trial: ACTRN12605000569606).

Inadequate vitamin D levels are associated with culture positive sepsis and poor outcomes in paediatric intensive care

AIM

This study aimed to assess vitamin D status, and its determinants, in paediatric patients with suspected sepsis who were admitted to a paediatric intensive care unit (PICU). We also investigated the association between vitamin D status and clinical outcomes.

METHODS

Serum 25-hydroxy vitamin D (25OHD) and clinical determinants were prospectively assessed in children with suspected sepsis (<12 years old) admitted to the PICU. The relationship between 25OHD and clinical outcomes was evaluated. Vitamin D status was also assessed in control children of a similar age.

RESULTS

We enrolled 120 children with suspected sepsis admitted to the PICU and 30 paediatric controls. 25OHD was <50 nmol/L in 59% of the children admitted to the PICU and 25OHD was lower than in the controls (47 ± 29 vs 66 ± 26 nmol/L, p < 0.001). After adjusting for potential confounders, 25OHD was strongly associated with culture positive sepsis (p < 0.001), the paediatric index of mortality (p = 0.026) and the duration of mechanical ventilation (p = 0.008). There was a negative correlation between 25OHD and C-reactive protein (CRP): each 0.1% decrease in 25OHD increased CRP (p = 0.04).

CONCLUSION

Children admitted to the PICU with suspected sepsis had lower 25OHD than controls and inadequate 25OHD status was associated with confirmed sepsis and poor outcomes.

Childhood asthma and spirometric indices are associated with polymorphic markers of two vitamin D 25-hydroxylase genes

BACKGROUND

Polymorphic markers of vitamin D pathway genes have been associated with asthma traits in different White populations. This study investigated the relationship between asthma phenotypes and single nucleotide polymorphisms (SNPs) of vitamin D receptor (VDR), vitamin D binding protein (GC), two 25-hydroxylases (CYP2R1 and CYP27A1), and 1α-hydroxylase (CYP27B1) in Hong Kong Chinese children.

METHODS

23 SNPs of the five vitamin D pathway genes were successfully genotyped in 914 asthmatic children and 1231 non-allergic controls. Genotypic and haplotypic associations with asthma phenotypes (diagnosis, spirometric indices, total IgE, and eosinophil percentage) were analyzed by multivariate regression. Generalized multifactor dimensionality reduction was used to detect epistatic interactions between SNPs for asthma phenotypes.

RESULTS

Several SNPs of CYP27A1, CYP27B1, GC, and CYP2R1 were associated with asthma or spirometric indices, although only the association between FEV1 and CYP2R1 rs7935792 passed Bonferroni correction (p = 2.73 × 10(-4) ). Patients with CC genotype of rs7935792 had higher FEV1 than those with the other two genotypes. Asthma was also associated with TT haplotype of CYP27A1 and AGGATA haplotype of CYP2R1 (p = 0.021 and 0.024, respectively). Besides, strong association was found between FEV1 and GATAG of CYP2R1 (β = 13.37, p = 4.83 × 10(-4) ). GMDR failed to identify any 2-locus to 4-locus interaction that modulated asthma or spirometric indices.

CONCLUSIONS

Several SNPs and haplotypes of CYP2R1 are associated with asthma diagnosis and FEV1 in children. Asthma is also modestly associated with a CYP27A1 haplotype. These two 25-hydroxylase genes may be genetic determinants for asthma phenotypes in children.

Dichotomy of short and long thymic stromal lymphopoietin isoforms in inflammatory disorders of the bowel and skin

Background

Thymic stromal lymphopoietin (TSLP) is a cytokine with pleiotropic functions in the immune system. It has been associated with allergic reactions in the skin and lungs but also homeostatic tolerogenic responses in the thymus and gut.

Objective

In human subjects TSLP is present in 2 isoforms, short and long. Here we wanted to investigate the differential expression of the TSLP isoforms and discern their biological implications under homeostatic or inflammatory conditions.

Methods

We evaluated the expression of TSLPs in tissues from healthy subjects, patients with ulcerative colitis, patients with celiac disease, and patients with atopic dermatitis and on epithelial cells and keratinocytes under steady-state conditions or after stimulation. We then tested the immune activity of TSLP isoforms both in vitro and in vivo.

Results

We showed that TSLP isoforms are responsible for 2 opposite immune functions. The short isoform is expressed under steady-state conditions and exerts anti-inflammatory activities by affecting the capacity of PBMCs and dendritic cells to produce inflammatory cytokines. Moreover, the short isoform TSLP ameliorates experimental colitis in mice and prevents endotoxin shock. The long isoform of TSLP is proinflammatory and is only expressed during inflammation. The isoforms are differentially regulated by pathogenic bacteria, such as Salmonella species and adhesive-invasive Escherichia coli.

Conclusions

We have solved the dilemma of TSLP being both homeostatic and inflammatory. The TSLP isoform ratio is altered during several inflammatory disorders, with strong implications in disease treatment and prevention. Indeed, targeting of the long isoform of TSLP at the C-terminal portion, which is common to both isoforms, might lead to unwanted side effects caused by neutralization of the homeostatic short isoform.

Serum vitamin D levels in a cohort of adult and pediatric patients with eosinophilic esophagitis

BACKGROUND

Vitamin D deficiency has been associated with increased risk for severe asthma, challenge-proven food allergy, and severe atopic dermatitis. Vitamin D levels have not been reported in patients with eosinophilic esophagitis (EoE).

OBJECTIVE

To determine levels of 25-hydroxyvitamin D in a cohort of patients with EoE.

METHODS

Total serum 25-hydroxyvitamin D was measured using liquid chromatography with tandem mass spectroscopy in adults (n = 35) and children (n = 34) with EoE. Results were compared with patient demographics, EoE-specific disease parameters, markers of sensitization, and features of severity using multivariable logistic regression.

RESULTS

The median vitamin D level was 28.9 ng/mL. Patients with insufficient vitamin D (<30 ng/mL) were older (median 25.5 vs 16.2 years) and had a higher body mass index (median 25.2 vs 19.8 kg/m(2)). Peak median esophageal eosinophil counts were not significantly different for vitamin D insufficient and sufficient patient groups; however, higher vitamin D levels correlated with higher histologic eosinophil counts (R = 0.61, P = .03). Although there were no statistical differences in total IgE or levels of specific IgE between patients with vitamin D insufficiency and those with sufficiency, a positive skin prick test reaction to peanut was more common in patients who had vitamin D insufficiency (adjusted odds ratio 7.57, P = .009). Vitamin D insufficiency was not associated with surrogate markers of severity (dilation in adults or hospitalization or emergency visits in children).

CONCLUSION

In these patients with EoE, vitamin D levels were low overall (median <30 ng/mL). The only marker of sensitization associated with insufficient vitamin D in these patients with EoE was a positive skin prick test reaction to peanut.

Vitamin D and the Development of Atopic Eczema

A “vitamin D hypothesis” has been proposed to explain the increased prevalence of eczema in regions with higher latitude. This review focuses on the current available evidence with regard to the possible effect of vitamin D on the development of atopic eczema. Observational studies have indicated a link between vitamin D status and eczema outcomes, including lower serum vitamin D levels associated with increased incidence and severity of eczema symptoms. Vitamin D is known to have a regulatory influence on both the immune system and skin barrier function, both critical in the pathogenesis of eczema. However heterogeneous results have been found in studies to date investigating the effect of vitamin D status during pregnancy and infancy on the prevention of eczema outcomes. Well-designed, adequately powered, randomised controlled trials are needed. The study design of any new intervention trials should measure vitamin D levels at multiple time points during the intervention, ultraviolet (UV) radiation exposure via the use of individual UV dosimeters, and investigate the role of individual genetic polymorphisms. In conclusion, the current available evidence does not allow firm conclusions to be made on whether vitamin D status affects the development of atopic eczema.

Vitamin D and atopic dermatitis in childhood

Vitamin D features immunomodulatory effects on both the innate and adaptive immune systems, which may explain the growing evidence connecting vitamin D to allergic diseases. A wealth of studies describing a beneficial effect of vitamin D on atopic dermatitis (AD) prevalence and severity are known. However, observations linking high vitamin D levels to an increased risk of developing AD have also been published, effectively creating a controversy. In this paper, we review the existing literature on the association between AD and vitamin D levels, focusing on childhood. As of today, the role of vitamin D in AD is far from clear; additional studies are particularly needed in order to confirm the promising therapeutic role of vitamin D supplementation in childhood AD.

Comparing the effects of sun exposure and vitamin D supplementation on vitamin D insufficiency, and immune and cardio-metabolic function: the Sun Exposure and Vitamin D Supplementation (SEDS) Study

Background

Adults living in the sunny Australian climate are at high risk of skin cancer, but vitamin D deficiency (defined here as a serum 25-hydroxyvitamin D (25(OH)D) concentration of less than 50 nmol/L) is also common. Vitamin D deficiency may be a risk factor for a range of diseases. However, the optimal strategies to achieve and maintain vitamin D adequacy (sun exposure, vitamin D supplementation or both), and whether sun exposure itself has benefits over and above initiating synthesis of vitamin D, remain unclear.

The Sun Exposure and Vitamin D Supplementation (SEDS) Study aims to compare the effectiveness of sun exposure and vitamin D supplementation for the management of vitamin D insufficiency, and to test whether these management strategies differentially affect markers of immune and cardio-metabolic function.

Methods/Design

The SEDS Study is a multi-centre, randomised controlled trial of two different daily doses of vitamin D supplementation, and placebo, in conjunction with guidance on two different patterns of sun exposure. Participants recruited from across Australia are aged 18–64 years and have a recent vitamin D test result showing a serum 25(OH)D level of 40–60 nmol/L.

Discussion

This paper discusses the rationale behind the study design, and considers the challenges but necessity of data collection within a non-institutionalised adult population, in order to address the study aims. We also discuss the challenges of participant recruitment and retention, ongoing engagement of referring medical practitioners and address issues of compliance and participant retention.

Trial registration

Australia New Zealand Clinical Trials Registry: ACTRN12613000290796 Registered 14 March 2013.

Serum 25(OH)D concentrations and atopic diseases at age 10: results from the GINIplus and LISAplus birth cohort studies

Background

Vitamin D is well recognized for its role in skeletal health and its involvement in the modulation of the immune system. In the literature, controversial results are reported for atopic diseases. Thus, we investigated the association between vitamin D status and the prevalence of atopic diseases.

Methods

Serum 25-hydroxy-vitamin D (25(OH)D) concentrations were measured in a sample of 2815 10-years old children from two German birth cohort studies. Self-reported physician-diagnosed eczema, hay fever or allergic rhinitis, and asthma were used as outcome variables as well as specific IgE positivity against common allergens. We applied logistic regression models, deriving adjusted odds ratio estimates (aOR) and 95% confidence intervals (CI).

Results

For asthma and hay fever or allergic rhinitis, no associations existed with serum 25(OH)D concentrations. We observed a significant positive relationship between serum 25(OH)D levels and eczema at age 10 (aOR = 1.09, CI = 1.01-1.17, per 10 nmol/l increase in serum 25(OH)D levels) and for the lifetime prevalence of eczema (aOR = 1.05, CI = 1.01-1.09). Specific IgE positivity for food allergens (aOR = 1.07, CI = 1.02-1.11) and aeroallergens (aOR = 1.05, CI = 1.01-1.08) at age 10, as well as lifetime prevalence, was significantly related to the vitamin D status.

Conclusion

In this study we found no indication that higher blood 25(OH)D levels are associated with decreased risk for any of the atopic outcomes in children. However, we observed a positive association of serum 25(OH)D concentrations with eczema and detectable specific IgE. Due to the given limitations of our study, the clinical relevance of these findings needs further clarification.

Electronic supplementary material

The online version of this article (doi:10.1186/s12887-014-0286-3) contains supplementary material, which is available to authorized users.

Recent advances in epidemiology and prevention of atopic eczema

Atopic dermatitis (AD), named also atopic eczema, is a chronic relapsing inflammatory skin disease with a considerable social and economic burden. The primum movens of AD is in most cases a genetic and/or immune-supported defect of the skin barrier, facilitating penetration and sensitization to food or airborne allergens, as well as infections by Staphylococcus aureus, herpes simplex virus, or other microbes. New pathogenetic concepts have generated new approaches to prevention and therapy of AD. In particular, the daily use of emollients in newborns at high risk of AD has shown interesting results, with a reduction in the cumulative incidence of AD ranging from 32% to 50% of the treated infants. On the other hand, the AD preventive efficacy of food and/or inhalant allergen avoidance has been questioned, and supplementation strategies (vitamin D, probiotics, or other compounds) need to be further investigated.

Dietary elimination of children with food protein induced gastrointestinal allergy - micronutrient adequacy with and without a hypoallergenic formula?

Background

The cornerstone for management of Food protein-induced gastrointestinal allergy (FPGIA) is dietary exclusion; however the micronutrient intake of this population has been poorly studied. We set out to determine the dietary intake of children on an elimination diet for this food allergy and hypothesised that the type of elimination diet and the presence of a hypoallergenic formula (HF) significantly impacts on micronutrient intake.

Method

A prospective observational study was conducted on children diagnosed with FPIGA on an exclusion diet who completed a 3 day semi-quantitative food diary 4 weeks after commencing the diet. Nutritional intake where HF was used was compared to those without HF, with or without a vitamin and mineral supplement (VMS).

Results

One-hundred-and-five food diaries were included in the data analysis: 70 boys (66.7%) with median age of 21.8 months [IQR: 10 - 67.7]. Fifty-three children (50.5%) consumed a HF and the volume of consumption was correlated to micronutrient intake. Significantly (p <0.05) more children reached their micronutrient requirements if a HF was consumed. In those without a HF, some continued not to achieve requirements in particular for vitamin D and zinc, in spite of VMS.

Conclusion

This study points towards the important micronutrient contribution of a HF in children with FPIGA. Children, who are not on a HF and without a VMS, are at increased risk of low intakes in particular vitamin D and zinc. Further studies need to be performed, to assess whether dietary intake translates into actual biological deficiencies.

Novel investigational therapies for atopic dermatitis

Introduction: Atopic dermatitis (AD) is a common skin disease. Although most patients are well served by existing therapies, a subset of patients with severe AD are still not adequately treated. An improved understanding of the pathogenic mechanisms behind the disease has led to the development of a range of potential new drugs for this indication. Areas covered: The authors provide a narrative review of the drugs in Phase II trials listed on Clinicaltrials.gov. The authors supplement this information with recently published literature located through PubMed. The main target of new treatments appears to be the inflammation process, whereas drugs aimed at reducing itching or increasing the barrier function are fewer to nonexistent. A wide range of drugs, including small molecules and antibodies, are being tested. Expert opinion: The focus on inflammation is not only driven by the limitations posed by our current understanding of biology, but also by the broader scope of these drugs, which may be used in other diseases. In alignment with the recent drug development of other dermatological diseases, antibodies directed at key molecules in the pathogenesis of AD appear to be the most promising.

New developments in the treatment of pediatric allergic rhinitis and conjunctivitis

The primary care physician is the first line of treatment for allergic rhinitis, which affects approximately one-fourth of children in the United States. There is an increasing trend toward self-management by patients or parents due to high-deductible insurance plans and the over-the-counter availability of allergy medications. The primary care physician can offer guidance on appropriate selection of medications and potential adverse effects. Vitamin D deficiency has been proposed as a potential contributing factor in patients with allergic diseases, and studies are underway to determine whether supplementation with vitamin D is helpful for these conditions. Sublingual immunotherapy has recently received US Food and Drug Administration approval for grass and ragweed allergens; many children will be interested in this alternative to allergy shots. The relative advantages and disadvantages of sublingual vs subcutaneous immunotherapy are discussed.