Atopic dermatitis: Correlation of severity with allergic sensitization and eosinophilia

Paraben exposure related to Staphylococcal enterotoxin IgE sensitization, allergic rhinitis and nasal patency in children

The study aims to investigate the link between paraben exposure, Staphylococcal enterotoxin IgE sensitization, and their combined relationship on allergic rhinitis and nasal patency in children. We assessed 276 children aged 10-12, examining their demographic backgrounds, atopy status, prevalence of allergic diseases, and serum specific IgE levels for Staphylococcal enterotoxins A, B, and toxic shock syndrome toxin (TSST). Parabens metabolites in urine samples were measured to assess exposure levels. The cohort included 276 children (mean 10.9 years), comprising 119 males and 157 females. Of these, 157 children (57.7%) were diagnosed with allergic rhinitis, 44 (15.9%) tested positive for Staphylococcal enterotoxins A, 33 (12.0%) for Staphylococcal enterotoxins B, and 94 (34.1%) for TSST. Propyl paraben was significantly associated with greater TSST-IgE concentrations in the highest quartile (aOR: 2.578, 95% CI 1.275 to 5.212, P = .008) and ethyl paraben showed similar associations in the highest quartile (aOR 2.637; 95% CI 1.223 to 5.669. P = .013). No significant associations were found with other paraben metabolites. Increased propyl paraben levels were linked to greater nasal airway patency, but no direct link to allergic rhinitis was observed. Participants with elevated TSST-IgE concentrations showed a higher odds ratio for allergic rhinitis (aOR: 1.808; 95% CI 1.054 to 3.100, P = .0.032). We observed a significant association between Staphylococcal enterotoxin IgE sensitization and paraben exposure in children. This association might influence allergic rhinitis and nasal response to decongestants, enhancing our understanding of environmental factors in pediatric allergies.

Efficacy of corneal squamous cell carcinoma antigen-1 in early infancy in predicting atopic dermatitis and food allergy: A prospective study

BACKGROUND

Identification of predictive biomarkers is crucial for formulating preventive interventions and halting the progression of atopic march. Although controversial, the use of accessible markers to predict or detect early onset of atopic diseases is highly desirable. Therefore, this study aimed to investigate whether corneal squamous cell carcinoma antigen-1 (SCCA1) collected from infants can predict the development of atopic dermatitis and food allergy.

METHODS

This prospective study enrolled 117 infants aged 2 months (55 female and 62 male infants). The participants were monitored to evaluate the occurrence of eczematous changes at several time points, and stratum corneum samples were obtained. The association of corneal SCCA1 with the development of atopic dermatitis and food allergy in the first 3 years of life was evaluated using univariate and multivariate logistic regression.

RESULTS

The corneal SCCA1 level was significantly higher in children who developed atopic dermatitis than in children who did not (cheek at 2 months: 1653.06 ± 178.48 ng/mg vs. 786.95 ± 101.59 ng/mg, P = 0.0033). The corneal SCCA1 level was also significantly higher in children who developed food allergy than in children who did not (perioral skin at 2 months: 2567.31 ± 408.09 ng/mg vs. 1120.85 ± 188.49 ng/mg, P = 0.0018).

CONCLUSIONS

The findings suggest that non-invasive measurements of corneal SCCA1 at 2 months of age is useful for predicting atopic dermatitis and food allergy in infants at risk for atopic dermatitis and subsequent food allergy.

Age-related effects of Mycoplasma pneumoniae infection and subsequent asthma exacerbation in children

BACKGROUND

Mycoplasma pneumoniae causes community-acquired pneumonia in children and increases asthma risk, but large studies are lacking.

OBJECTIVE

To assess the link between M. pneumoniae infection and to asthma exacerbation, in children with allergies, and age of infection impact.

METHODS

This retrospective cohort study analyzed medical records of South Korean children between January 2002 and December 2017. The study's exposure was hospitalization with an M. pneumoniae-related diagnosis, and the outcome was defined as asthma exacerbation, confirmed by hospitalization at least 6 months after M. pneumoniae infection, with alternative validation using asthma diagnosis and systemic steroid prescription records. Hazard ratios (HRs) for asthma exacerbation risk were estimated for the matched cohort using a Cox proportional hazards model stratified by allergic comorbidities. Time-dependent covariates and age-stratified exposure groups were used to calculate odds ratios.

RESULTS

The study included 84,074 children with M. pneumoniae infection and 336,296 unexposed children. Follow-up for 12.2 ± 2.3 years found the exposed group had a significant risk of asthma exacerbation (HR 2.86, 95% confidence interval [CI] 2.67-3.06) regardless of allergic comorbidities. The risk was highest (over threefold) in children infected between 24 and 71 months. Sensitivity analysis using an alternative definition of the outcome showed an HR of 1.38 (95% CI 1.35-1.42), further supporting the association between M. pneumoniae infection and asthma exacerbation.

CONCLUSION

M. pneumoniae infection was significantly associated with an increased risk of subsequent asthma exacerbation regardless of allergic comorbidities. Further research needed for understanding and confirmation.

Population-based cohort study to investigate the changes in prevalence, severity profile, and treatment modalities used in Korean atopic dermatitis patients

In this retrospective study spanning from 2002 to 2019, we analyzed data from 355,277 Korean patients diagnosed with atopic dermatitis (AD) through the National Health Insurance System. Our objective was to comprehensively analyze the trends in prevalence, severity profiles, and treatment approaches for AD in Korea over this 18-year period. Initially, AD prevalence stood at 3.88% in 2002 but notably rose to 5.03% by 2019. During the same period, while AD prevalence decreased in the 0-1-year-old group (from 34.52% to 24.83%), it remained relatively stable in the 1-11-year-old group. Conversely, the 12-19-year-old and 20 years or older age groups witnessed substantial increases in AD prevalence, climbing from 2.55 to 6.02% and 1.44% to 3.53%, respectively. Moreover, the proportion of patients classified as having moderate to severe AD grew from 30.96 to 39.78%. Surprisingly, the prescription pattern, predominantly based on corticosteroid administration, exhibited minimal change despite the rising prevalence of moderate and severe AD cases. These findings underline a persistent reliance on corticosteroid-based treatments for AD, even as the condition's severity escalates among Korean adolescents and adults. Consequently, there is a pressing need to develop novel treatment guidelines emphasizing biologics that offer enhanced safety and efficacy.

Vitamin D level is inversely related to allergen sensitization for risking atopic dermatitis in early childhood

Background

There are few studies concerning the impact of serum vitamin D status on the risk of allergen sensitization and atopic dermatitis (AD) during early childhood.

Method

Children with AD and age-matched healthy controls (HC) were prospectively enrolled at age 0.5, 2, and 4 years. Serum 25-hydroxyvitamin D (25[OH]D) level was measured using Elecsys Vitamin D Total assay. The study utilized the ImmunoCAP assay to analyze specific IgE for food and inhalant allergens, along with total serum IgE levels. It explored the connection between vitamin D levels and allergen sensitization, as well as their influence on AD at different ages.

Results

A total of 222 children including 95 (59 AD and 36 HC), 66 (37 AD and 29 HC), and 61 (32 AD and 29 HC) children were classified at age 0.5, 2, and 4 years, respectively. In children with AD, there was a significantly lower vitamin D level at age 2 and 4, but a significantly higher prevalence of food and mite sensitization at all ages in comparison with HC (P < 0.001). Vitamin D level was found to be inversely related to the prevalence of allergen sensitization at age 4 (P < 0.05). However, vitamin D level appeared to have high importance for allergen sensitization at all ages and AD at age 2 and 4 years.

Conclusion

Vitamin D deficiency is strongly associated with heightened prevalence of allergen sensitization, potentially increasing the susceptibility to AD in early childhood.

Limited clinical role of blood eosinophil levels in early life atopic disease: A mother-child cohort study

BACKGROUND

Blood eosinophil count is a well-established biomarker of atopic diseases in older children and adults. However, its predictive role for atopic diseases in preschool children is not well established.

OBJECTIVE

To investigate the association between blood eosinophil count in children and development of atopic diseases up to age 6 years.

METHODS

We investigated blood eosinophil count at age 18 months and 6 years in relation to recurrent wheeze/asthma, atopic dermatitis, allergic rhinitis, and allergic sensitization during the first 6 years of life in the two Copenhagen Prospective Studies on Asthma in Childhood cohorts (n = 1111). Blood eosinophil count was investigated in association with remission of existing atopic disease, current atopic disease, and later development of atopic disease.

RESULTS

Blood eosinophil count at 18 months was not associated with current wheezing/asthma or atopic dermatitis, while blood eosinophil count at age 6 years was associated with increased occurrence of current wheezing/asthma (OR = 1.1; 1.04-1.16, p = .0005), atopic dermatitis (OR = 1.06; 1.01-1.1, p = .02), and allergic rhinitis (OR = 1.11; 1.05-1.18, p = .0002). Blood eosinophil count at 18 months did not predict persistence or development of recurrent wheeze/asthma or atopic dermatitis at age 6 years.

CONCLUSION

Blood eosinophil count at 18 months was not associated with current wheezing/asthma or atopic dermatitis and did not predict persistence or development of disease. This implies a limited clinical role of blood eosinophil levels in early-life atopic disease and questions the clinical value of blood eosinophil counts measured in toddlers as a predictive biomarker for subsequent atopic disease in early childhood.

Factors associated with severity of atopic dermatitis - a Finnish cross-sectional study

BACKGROUND

Severity-associated factors in atopic dermatitis (AD) have focussed on early onset, concomitant atopic diseases, markers of Th2-shifted inflammation and filaggrin mutations.

OBJECTIVES

To investigate factors associated with severe AD in Finnish patients.

METHODS

We conducted a single-centre, cross-sectional observational study with 502 AD patients aged 4.79 to 79.90 years (mean 32.08 years). Disease severity was assessed with the Rajka-Langeland severity score and EASI and associated clinical signs were evaluated. Data regarding onset, relatives, atopic and other comorbidities was gathered retrospectively. We investigated total serum IgE-levels, a panel of filaggrin null mutations and functional variants of genes associated with skin barrier defects.

RESULTS

Factors more frequent in severe AD included early onset (P = 0.004, 95%CI 0.000-0.024), male sex (P = 0.002, 95%CI 0.000-0.11), history of smoking (P = 0.012, 95%CI 0.000-0.024), concomitant asthma (P = 0.001, 95%CI 0.000-0.011), palmar hyperlinearity (P = 0.013, 95%CI 0.014-0.059), hand dermatitis (P = 0.020, 95%CI 0.000-0.029) and history of contact allergy (P = 0.042, 95%CI 0.037-0.096). Body mass indices (P < 0.000, 95%CI 0.000-0.011) and total serum IgE-levels (P < 0.000, 95%CI 0.000-0.011) were higher in severe AD. No differences were observed for allergic rhinitis, allergic conjunctivitis, food allergy, peanut allergy, prick positivity, keratosis pilaris, history of herpes simplex infections, filaggrin null mutations and other gene variants.

CONCLUSIONS

Severity determinants in Finnish patients seem to be early-onset, male sex, smoking, overweight, concomitant asthma, palmar hyperlinearity, hand dermatitis and high IgE-levels. A sub-typing of patients in relation to confirmed severity determinants may be useful for course prediction, prognosis and targeted AD management.

Serum thymus and activation-regulated chemokine (TARC) levels correlate with atopic dermatitis disease severity in patients < 6 months

Background: Atopic dermatitis (AD) may develop by 6 months of age, and its severity assessment is essential for appropriate treatments. Scoring Atopic Dermatitis (SCORAD) is suggested to evaluate the severity of AD but is cumbersome for routine clinical use. The serum thymus and activation-regulated chemokine (TARC) is used as a marker of AD severity. However, the normal range of the TARC levels varies by age, and its usefulness for the evaluation of AD severity has not been established in patients ages < 6 months. Here, we evaluated the correlation between serum TARC levels and SCORAD scores in early infancy and sought the optimal cutoff level to indicate AD severity. Methods: The subjects were 35 patients with AD (16 girls and 19 boys; 3-5 months of age) who visited our clinic between April 2015 and March 2017. All the patients were physically examined by a board-certified allergist. The AD severity was determined by using the SCORAD, together with serum levels of TARC, total immunoglobulin E (IgE), lactate dehydrogenase, and peripheral eosinophil counts. Receiver operating characteristic curve analysis was performed to determine the cutoff levels of serum TARC to indicate AD severity. Results: Significant correlations were observed between SCORAD scores and the serum TARC levels, peripheral eosinophil counts, and serum IgE levels (r = 0.640, r = 0.723, r = 0.533, respectively). The optimal cutoff levels of serum TARC to indicate mild and severe AD were <3523 pg/mL (area under the curve [AUC] = 0.856) and >6192 pg/mL (AUC = 0.833), respectively. Conclusion: Although this study had limitations, we suggest that serum TARC is useful as a marker of AD severity in patients <6 months of age.

Vitamin D, skin filaggrin, allergic sensitization, and race

BACKGROUND

In addition to its involvement in both the innate and adaptive immune systems, vitamin D has been found to affect keratinocyte function and proliferation, suggesting a possible role for vitamin D in cutaneous allergic sensitization.

OBJECTIVE

To explore the role of circulating vitamin D levels in allergic sensitization.

METHODS

Serum 25-hydroxyvitamin D (25(OH)D) levels were measured in a subset of children (N = 323) enrolled in the Mechanisms of Progression of Atopic Dermatitis to Asthma in Children cohort, a prospective early life cohort of children with atopic dermatitis. Allergic sensitization was determined using skin prick testing, and FLG expression in the keratinocytes was measured by quantitative polymerase chain reaction. Multiple Poisson regression was used to evaluate interaction effects between serum 25(OH)D levels and FLG expression with sensitization load as the outcome.

RESULTS

Black participants had significantly lower mean levels of serum 25(OH)D compared with non-Black participants (29.3 vs 32.9 ng/mL; P < .001). FLG expression and sensitization load were negatively correlated in non-Black participants with 25(OH)D levels less than 27.2 ng/mL (Rho = -0.45; P = .02). No association between FLG expression and sensitization load was found in Black participants or participants with 25(OH)D levels greater than or equal to 27.2 ng/mL. Multiple Poisson regression models confirmed that 25(OH)D levels interact with FLG expression to affect sensitization load in non-Black participants.

CONCLUSION

Despite lower vitamin D levels in Black participants, sensitization load was associated with nonlesional skin FLG expression in non-Black, but not Black, children with low vitamin D levels. Thus, a complex interplay of factors determines the impact of vitamin D on allergic sensitization.

Personal Exposure to Total VOC Is Associated With Symptoms of Atopic Dermatitis in Schoolchildren

BACKGROUND

The urinary levels of volatile organic compound (VOC) metabolites provide individual exposure levels compared to data obtained by measuring these compounds in ambient air. We aimed to investigate the association between personal urinary concentrations of VOC metabolites and symptoms of atopic dermatitis in schoolchildren.

METHODS

Nine urinary VOC metabolites were analyzed from urine samples of 149 children. Diagnosis of atopic dermatitis was determined using standardized questionnaires. Pediatricians visited the schools and rated the severity of symptoms using the SCORing Atopic Dermatitis (SCORAD) in all children.

RESULTS

Forty-five children (30.2%) had atopic dermatitis based on the International Study of Asthma and Allergies in Childhood (ISAAC) results and 35 children (23.8%) had symptoms of atopic dermatitis with positive SCORAD index values (defined as SCORAD ≥ 5). Children with benzylmercapturic acid detected in personal urines were associated with presence of atopic dermatitis and positive SCORAD index values. Children in the highest quartile of mandelic acid concentration were associated with presence of atopic dermatitis and positive SCORAD results.

CONCLUSION

Personal exposure to VOCs, as indicated by urinary levels of VOC metabolites, was associated with presence of atopic dermatitis and the SCORAD index value.

Association of clinical and social factors with risk of fracture in children with atopic dermatitis

BACKGROUND

Children with atopic dermatitis (AD) have multiple risk factors for accidental fractures, injuries that can lead to significant morbidity and mortality. However, little is known about the factors that mediate the relationship between AD and fracture in children.

OBJECTIVE

Our purpose was to examine the association of AD with fracture and to identify potential mediating factors.

METHODS

This retrospective cohort study examined children with and without AD from a longitudinal matched cohort database of 353,040 children registered in the national health insurance service and participated in the national health-screening program of Korea. We defined AD using medical claims and medication prescription records. We investigated accidental fracture events between the index date and the end of follow-up in a propensity score-matched cohort. Pre-specified subgroup analyses considered fractures in four different regions of the body. The mediating effects of 10 possible clinical factors (including the use of antihistamines and systemic corticosteroids) and social factors (including nutritional status and parental safety awareness) were determined.

RESULTS

There were 145,704 participating children, 20% with AD and 49% girls. Fractures occurred in 6,652 of the children with AD (23%, mean age: 64.6 ± 29.2 months) and in 24,698 of the control group (21%, mean age 65.0 ± 28.9 months). Children with AD had an 8% greater risk of fracture events overall (adjusted relative risk [aRR]: 1.08, 95% CI: 1.05-1.10). In subgroup analysis, AD was related to increased rates of skull and facial bone fracture (aRR: 1.09, 95% CI: 1.04-1.14), for trunk including vertebrae (aRR: 1.58, 95% CI: 1.22- 2.05), and for distal limbs (aRR: 1.11, 95% CI: 1.07-1.15). However, the relationship with proximal limb fracture was insignificant. Duration of systemic corticosteroid prescription was the largest mediating factor, followed by duration of antihistamine prescription, and infant feeding practices. In particular, the duration of systemic corticosteroid prescription was significantly associated with fracture events (incidence: 20.1% at the 25th percentile and 23.6% at the 75th percentile; difference: 3.4% [95% CI: 2.8-4.0%]).

CONCLUSIONS

Children with AD were related to increased fracture events. The key factors with mediating effects were systemic use of corticosteroid and antihistamine. Infant feeding practices had weaker mediating effects.