Phenotypic analysis of atopic dermatitis in children aged 1-12 months: elaboration of novel diagnostic criteria for infants in China and estimation of prevalence

Alterations in gut microbiome associated with severity of atopic dermatitis in infants

BACKGROUND

Atopic dermatitis (AD) often arises in infancy, and gut microbial dysbiosis is associated with the development of AD. However, less is known about specific changes in early-life gut microbiome associated with AD and AD severity. This study aims to reveal the gut microbial composition and function profiles associated with the severity of AD in infants.

METHODS

Sixty-two infants (mean [SD] age, 4.7[1.9] months) with different severities of AD were enrolled and divided into three groups (mild, moderate and severe) according to the Scoring Atopic Dermatitis (SCORAD) index. The profiles of gut microbial composition and function were analysed by sequencing 16S ribosomal RNA amplicons. Quality of life on children and the family was evaluated using published questionnaires.

RESULTS

Decreased levels of Clostridium sensu stricto, Collinsella and increased level of Parabacteroides presented in the severe AD group compared with the mild AD group after adjusting potential confounders (p < 0.05). There were strong positive correlations between the Scoring Atopic Dermatitis (SCORAD) index and the relative abundance (RA) of Bacteroides and functional pathways for metabolism of sphingolipids and glycosphingolipids (p < 0.05). The SCORAD index was negatively correlated with the RA of Clostridium sensu stricto (p < 0.05), and was also positively correlated with the index of quality of life on children and the family (p < 0.05).

CONCLUSION

Discrepancies in gut microbial composition and functional pathways were observed in infants with mild-to-severe AD. Alterations in butyrate-producing bacteria (Clostridium sensu stricto), sphingolipid-producing bacteria (Parabacteroides, Bacteroides), and related functional pathways were associated with the severity of AD infants.

Efficacy and Safety of Crisaborole Ointment 2% in Chinese Patients Aged ≥ 2 Years with Mild to Moderate Atopic Dermatitis

INTRODUCTION

Atopic dermatitis (AD) is a chronic immuno-inflammatory skin disease. Crisaborole ointment, 2%, is a nonsteroidal phosphodiesterase 4 inhibitor approved for the treatment of mild to moderate AD. This post hoc analysis assesses the efficacy and safety of crisaborole in Chinese patients aged ≥ 2 years with mild to moderate AD.

METHODS

We evaluated the efficacy and safety of crisaborole in Chinese patients from the vehicle-controlled, phase 3 CrisADe CLEAR study. Patients were randomly assigned 2:1 to receive crisaborole or vehicle twice daily, respectively, for 28 days. The primary endpoint was percent change from baseline in Eczema Area and Severity Index (EASI) total score at day 29. Key secondary endpoints were improvement in Investigator's Static Global Assessment (ISGA), ISGA success, and change from baseline in weekly average Peak Pruritus Numerical Rating Scale (PP-NRS) score. Adverse events were documented.

RESULTS

Of 391 patients in the overall study, 237 were from China, 157 assigned to crisaborole and 80 assigned to vehicle. A greater reduction in percent change from baseline in EASI total score at day 29 was shown in the crisaborole vs. vehicle group (least squares mean [LSM]: -66.34 [95% (confidence interval) CI -71.55 to -61.12] vs. -50.18 [95% CI -58.02 to -42.34]). Response rates for achievement of ISGA improvement (43.2% [95% CI 35.4-51.1] vs. 33.4% [95% CI 22.5-44.2]) and ISGA success (31.7% [95% CI 24.3-39.0] vs. 21.5% [95% CI 12.1-30.9]) at day 29 were higher in the crisaborole vs. vehicle group. A greater reduction in change from baseline in weekly average PP-NRS score at week 4 was observed in the crisaborole vs. vehicle group (LSM: -1.98 [95% CI -2.34 to -1.62] vs. -1.08 [95% CI -1.63 to -0.53]). No new safety signals were observed.

CONCLUSION

Crisaborole was effective and well tolerated in Chinese patients aged ≥ 2 years with mild to moderate AD.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04360187.

The relationship between umbilical cord blood IL-22 level and infantile eczema at 42 days

Background

The occurrence of eczema is related to helper T 22 (Th22) cytokine disorder, and Th22 mainly secretes interleukin-22 (IL-22). This study aims to investigate the predictive value of umbilical cord blood IL-22 levels on the onset of eczema in infants within 42 days.

Study design

The study selected 157 full-term healthy neonates born between September 2020 and May 2021. Cord blood was collected immediately after birth to determine IL-22 levels, and the infants were followed up for 42 days to assess the incidence of eczema.

Results

Among the 157 infants who completed the 42-day follow-up, 86 developed eczema and 71 did not. The level of IL-22 in the umbilical cord blood of the eczema group was lower than that of the non-eczema group (p < 0.05). Additionally, the incidence of eczema in children whose Family history of allergy was significantly higher than in the group without eczema (p < 0.05). Logistic regression analysis indicated that low cord blood IL-22 levels and a family history of allergies were independent risk factors for eczema (p < 0.05). The ROC curve of cord blood IL-22 levels and infant eczema showed that the cut-off value is 36.362 pg/ml, the area under the curve (AUC) is 0.613, the standard error is 0.045, the 95% CI is 0.526-0.701, the sensitivity is 63.4%, and the specificity is 57.0%. Therefore, there is a certain correlation between cord blood IL-22 levels and the incidence of infant eczema.

Conclusions

Low IL-22 levels in umbilical cord blood may be linked to the development of infant eczema within 42 days, indicating a potential predictive value, although this value appears to be limited.

Low vitamin D during pregnancy is associated with infantile eczema by up-regulation of PI3K/AKT/mTOR signaling pathway and affecting FOXP3 expression: A bidirectional cohort study

Vitamin D has received increasing attention because of its association with atopic disease development. Limited studies that have been done on the impact of maternal vitamin D levels during pregnancy on infantile eczema are still debatable. We wanted to discover the effect of maternal vitamin D on infantile eczema and explore whether regulatory T cells (Treg) play a role in this process. 219 pairs of mothers and children were enrolled. Maternal fasting venous blood was collected in pregnancy's second and third trimesters to determine vitamin D levels. Cord blood and placenta samples were collected during childbirth for detecting levels of genes, proteins and cytokines. Pediatricians followed up the prevalence of eczema in infants within 1 year. The reported rate of vitamin D deficiency and insufficiency was 35.6% and 28.3%. Lower maternal 25(OH)D3 levels were related to a higher risk of infantile eczema. Foxp3 gene expression is lower in cord blood of infants with eczema compared to infants without eczema. There was a positive correlation between maternal 25(OH)D3 levels and the expression of FOXP3 gene in cord blood. Compared to vitamin D sufficiency women, vitamin D deficiency women's placental FOXP3 protein expression was decreased and PI3K/AKT/mTOR protein was up-regulated. Our study demonstrates that low prenatal maternal vitamin D levels increased the risk of infantile eczema aged 0-1 year, which might be related to the downregulating of the FOXP3 gene expression in cord blood and decreased placental FOXP3 protein expression. Low placental FOXP3 protein was related with activating PI3K/AKT/mTOR signaling pathway.

Esculentoside A ameliorates DNCB-induced atopic dermatitis by suppressing the ROS-NLRP3 axis via activating the Nrf2 pathway

Atopic dermatitis (AD) is a chronic inflammatory skin condition with a high prevalence. Inflammation and oxidative stress are strongly associated with AD progression. Esculentoside A (EsA) inhibits inflammation and oxidative stress in various diseases. However, whether EsA mitigates AD by suppressing inflammation and oxidative stress remains unknown. A mouse model of AD was constructed by the induction of 1-chloro-2,4-dinitrochlorobenzene (DNCB). The mechanism of EsA and its effects on AD symptoms, pathology, inflammation and oxidative stress were investigated through histopathological staining, enzyme-linked immunosorbent assay, blood cells analysis, colorimetric measurement and western blot analysis. EsA improved the clinical symptoms and increased clinical skin scores in AD mice. Skin thickening of the epidermis and dermal tissues and the mast cell numbers in AD mice were reduced with the EsA treatment. EsA decreased the relative mRNA level of thymic stromal lymphopoietin, interleukin (IL)-4, IL-5 and IL-13; the serum concentrations of immunoglobulin E (IgE) and IL-6; and the numbers of white blood cells (WBC) and WBC subtypes, including basophil, lymphocytes, eosinophil, neutrophil and monocytes in DNCB-induced mice. DNCB caused higher levels of oxidative stress, which was reversed with the administration of EsA. Mechanically, EsA upregulated the expression of Nrf2 but downregulated the level of NLRP3 inflammasome in AD mice. The inhibitor of Nrf2 significantly recovered the EsA-induced changes in the NLRP3 inflammasome proteins in DNCB-treated mice. Therefore, EsA improved the clinical and pathological symptoms, inflammation and oxidative stress experienced by DNCB-induced mice and was involved in the inactivation of NLRP3 inflammasome by activating Nrf2.

Trajectory of stratum corneum lipid subclasses in the first year of life and associations with atopic dermatitis: A prospective cohort study

BACKGROUND

Trajectories of stratum corneum (SC) lipid subclasses and their associations with infant atopic dermatitis (AD) are unclear. This study aimed to quantify the trajectories of 15 SC subclasses and carbon chain lengths and their associations with AD within 12 months.

METHODS

In total, 213 newborns were enrolled at birth with nonlesional skin samples collected from the inner forearm at birth, 42 days, 3, 6, and 12 months, respectively. Lesional skin samples were collected from 120 AD patients at clinic with the disease onset within the first year of life. Mass spectrometry was applied to assess relative contents of 12 ceramide (CER), three free fatty acid (FFA) subclasses, and average carbon chain length (CCL). AD incident within 1 year old was diagnosed by dermatologists according to UK criteria.

RESULTS

Sixty-four (30.0%) cases of ADs occurred in the cohort. All SC lipid subclasses and CCLs, but EOP varied significantly during the first year. AD infants showed lower NP but higher NS, NH, AP, hydroxy FFA, and CCL of FFAs compared with nonaffected infants. After normalization by age, the differences remained and were more pronounced in lesional skin of clinical AD infants compared with non-ADs. NS, NH, and CCL of FFAs in lesional skin of AD infants showed positive and significant correlations with the levels of transepidermal water loss at 3 month; some evidence supports a negative correlation for NP.

CONCLUSIONS

We provide an overview of developmental trajectories of 15 CER and FFA subclasses across the first year of healthy infants and a link between the imbalance of some subclasses with the development of AD.

Maternal supplementation with Limosilactobacillus reuteri FN041 for preventing infants with atopic dermatitis: study protocol for a randomized controlled trial

Background

Atopic dermatitis (AD) has increased rapidly with rapid urbanization; however, the treatment options for AD are lacking because the commonly used therapies can only alleviate symptoms. Limosilactobacillus reuteri (L. reuteri), FN041 is a specific strain isolated from human breast milk, and its protective potential against AD has been confirmed. This study aims to assess the efficacy of maternal consumption of L. reuteri FN041 during late pregnancy and lactation in preventing infantile AD.

Methods

First, a randomized, double-blind, placebo-controlled intervention study will be conducted on 340 pregnant females with babies at high risk for AD. These subjects will be randomly divided into four groups of different doses of L. reuteri FN041 (1 × 109, 5 × 109, and 1 × 1010 CFU/d) along with a placebo. The safety and efficacy of maternal use of L. reuteri FN041 for preventing infantile AD will be analyzed, and the most efficient dosage of L. reuteri FN041 will be determined. Subsequently, a multicenter cohort study of 500 pregnant females with babies at high risk for AD will be conducted to promote the maternal application of L. reuteri FN041. These subjects will be administered L. reuteri FN041 at the optimal dose determined during the first stage of late pregnancy and lactation, and their babies will be analyzed for AD development. Recruitment was initiated in October 2022.

Discussion

The primary outcome is the cumulative incidence of AD at 24 months after maternal consumption of L. reuteri FN041 during late pregnancy and lactation, whereas the secondary outcome is the efficiency of L. reuteri FN041 transfer from the mother's gut to breast milk and then the infant's gut after oral supplementation. This study will demonstrate the efficacy of edible probiotics isolated from breast milk in preventing or treating AD in infants. Accordingly, we provide population-based advice for administering specific probiotics for the primary prevention of AD in pregnant females. Understanding the underlying mechanisms of probiotic strains derived from breast milk can promote their application in preventing infant diseases associated with intestinal microbiota imbalance and immune disorders.

Clinical trial registration

https://www.chictr.org.cn/, identifier [ChiCTR2300075611].

Assessment of Anxiety, Depression, and Sleep Quality in Mothers of Children with Atopic Dermatitis: A Qualitative Questionnaire Study

Purpose

To compare the anxiety, depression and sleep quality of mothers of healthy control children and mothers of children with atopic dermatitis (AD) of varying severity, both before and after treatment.

Methods

A total of 120 parent-child dyads participated in the study. These dyads were divided into four subgroups of 30 patients each: mild AD, moderate AD, severe AD, and control groups. The children's symptoms, their mothers' psychological status, and their mothers' sleep quality were evaluated using the Scoring of Atopic Dermatitis (SCORAD), the Hospital Anxiety and Depression Scale (HADS), and the Pittsburgh Sleep Quality Index (PSQI), respectively, before and after a one-month comprehensive treatment.

Results

SCORAD, representing differences in severity of children's AD, decreased significantly after one month's treatment (p < 0.001). Anxiety in mothers significantly decreased in all AD severity groups after treatment (p < 0.05). However, for depression, only the mothers in the mild and moderate AD groups showed a decrease after treatment (p < 0.05). The PSQI total score also decreased in the mild AD group after treatment (p < 0.05).

Conclusion

The most severe effect was seen in the psychology and sleep quality of mothers of children with severe AD. After one month of treatment, the psychological health and sleep quality of the mothers in the mild AD group significantly improved, while those of mothers in the moderate and severe AD groups showed partial improvement.

Burden of Disease; the Current Status of the Diagnosis and Management of Atopic Dermatitis in China

Atopic dermatitis (AD) is now a global health problem and has been attracting extensive attention from both academic and public society in China. This review aimed to present the current status of the prevalence, disease burden, clinical features, diagnosis, and management of AD in China. The prevalence of AD has been increasing rapidly in China during the past decades, partially due to the increased recognition of the disease; there are still substantial amounts of over-diagnosed eczema and under-diagnosed AD. Chinese dermatologists see many AD patients with atypical manifestation, which poses a challenge to the diagnosis. The Chinese diagnostic criteria for adults and pediatric patients with AD have been proposed respectively and validated with high sensitivity and specificity. International and Chinese guidelines for management of AD have been popularized; however, there are still many practices that need verification through randomized case-control study. Dupilumab and JAK inhibitors have demonstrated favorable efficacy for AD patients in China, and a multidimensional approach is needed for selection of the patients and evaluation of the efficacy and safety. Patient education and long-term management for AD are just beginning in China, and need to be strengthened in the future.

A Web-Based Instrument for Infantile Atopic Dermatitis Identification (Electronic Version of the Modified Child Eczema Questionnaire): Development and Implementation

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory cutaneous disease that affects 30.48% of young children; thus, there is a need for epidemiological studies in community settings. Web-based questionnaires (WBQs) are more convenient, time-saving, and efficient than traditional surveys, but the reliability of identifying AD through WBQs and whether AD can be identified without the attendance of doctors, especially in community or similar settings, remains unknown.

OBJECTIVE

This study aimed to develop and validate a web-based instrument for infantile AD identification (electronic version of the modified Child Eczema Questionnaire [eCEQ]) and to clarify the possibility of conducting WBQs to identify infantile AD without the attendance of doctors in a community-representative population.

METHODS

This study was divided into 2 phases. Phase 1 investigated 205 children younger than 2 years to develop and validate the eCEQ by comparison with the diagnoses of dermatologists. Phase 2 recruited 1375 children younger than 2 years to implement the eCEQ and verify the obtained prevalence by comparison with the previously published prevalence.

RESULTS

In phase 1, a total of 195 questionnaires were analyzed from children with a median age of 8.8 (IQR 4.5-15.0) months. The identification values of the eCEQ according to the appropriate rules were acceptable (logic rule: sensitivity 89.2%, specificity 91.5%, positive predictive value 97.1%, and negative predictive value 72.9%; statistic rule: sensitivity 90.5%, specificity 89.4%, positive predictive value 96.4%, and negative predictive value 75%). In phase 2, a total of 837 questionnaires were analyzed from children with a median age of 8.4 (IQR 5.2-14.6) months. The prevalence of infantile AD obtained by the eCEQ (logic rule) was 31.9% (267/837), which was close to the published prevalence (30.48%). Based on the results of phase 2, only 20.2% (54/267) of the participants identified by the eCEQ had previously received a diagnosis from doctors. Additionally, among the participants who were not diagnosed by doctors but were identified by the eCEQ, only 6.1% (13/213) were actually aware of the possible presence of AD.

CONCLUSIONS

Infantile AD can be identified without the attendance of doctors by using the eCEQ, which can be easily applied to community-based epidemiological studies and provide acceptable identification reliability. In addition, the eCEQ can also be applied to the field of public health to improve the health awareness of the general population.

Validation of diagnostic criteria for atopic dermatitis and proposal of novel diagnostic criteria for adult and elderly Chinese populations: a multicentre, prospective, clinical setting-based study

BACKGROUND

A previous validation study showed a very low sensitivity and higher specificity associated with Hanifin and Rajka criteria (H&R) and the UK Working Party criteria (UKWP) in diagnosing AD vs. the Chinese criteria of atopic dermatitis (AD) for children (CCAD). However, their diagnostic efficacy in adult and elderly Chinese populations remains unknown.

OBJECTIVES

To validate the diagnostic efficacy of three sets of AD criteria in adult and elderly Chinese populations in a hospital setting.

METHODS

A total of 1034 patients (aged 19-95 years) from five university hospital dermatological clinics were recruited. Medical history, dermatological examination, AD diagnosis and evaluation of AD severity were done by dermatologists. Each patient was investigated by two dermatologist panels, one to establish a clinical diagnosis, and the other to identify and record the major or minor signs of H&R criteria, UKWP criteria and CCAD. Taking clinical diagnosis as the reference, the diagnostic efficacy of three sets of diagnostic criteria was evaluated. The χ2 test or rank sum test were used for between-groups comparisons.

RESULTS

CCAD had a higher sensitivity (84.0%), especially among mild and moderate cases of AD (72.7% and 90.3%, respectively), than the H&R (58.0%; P < 0.001) and UKWP criteria (56.0%; P < 0.001) in diagnosing AD. The specificity of CCAD (92.7%) was slightly lower than the H&R (97.3%; P < 0.001) or UKWP criteria (97.4%; P < 0.001). The CCAD had the highest Youden index (0.77), accuracy rate (0.90) and Kappa value (0.76) of the three sets of diagnostic criteria.

CONCLUSIONS

Consistent with results in a population of Chinese children, although the H&R and UKWP criteria had a high specificity for diagnosing AD, their low sensitivity limited their use in adult and elderly Chinese patients. Based on the high sensitivity and favourable diagnostic efficacy, the CCAD is proposed for AD diagnosis in adult and elderly Chinese populations, especially for cases of mild and moderate AD.

Lactobacillus for the treatment and prevention of atopic dermatitis: Clinical and experimental evidence

Atopic dermatitis (AD) is a chronic inflammatory skin disease, accompanied by itching and swelling. The main pathological mechanism of AD is related to the imbalance between Type 2 helper cells (Th2 cells) and Type 1 helper cells (Th1 cells). Currently, no safe and effective means to treat and prevent AD are available; moreover, some treatments have side effects. Probiotics, such as some strains of Lactobacillus, can address these concerns via various pathways: i) facilitating high patient compliance; ii) regulating Th1/Th2 balance, increasing IL-10 secretion, and reducing inflammatory cytokines; iii) accelerating the maturation of the immune system, maintaining intestinal homeostasis, and improving gut microbiota; and iv) improving the symptoms of AD. This review describes the treatment and prevention of AD using 13 species of Lactobacillus. AD is commonly observed in children. Therefore, the review includes a higher proportion of studies on AD in children and fewer in adolescents and adults. However, there are also some strains that do not improve the symptoms of AD and even worsen allergies in children. In addition, a subset of the genus Lactobacillus that can prevent and relieve AD has been identified in vitro. Therefore, future studies should include more in vivo studies and randomized controlled clinical trials. Given the advantages and disadvantages mentioned above, further research in this area is urgently required.

A cohort study of intrapartum group B streptococcus prophylaxis on atopic dermatitis in 2-year-old children

OBJECTIVE

To understand the occurrence of atopic dermatitis (AD) in children aged 2 years on exposure to maternal group B streptococcus (GBS) antibiotic prophylaxis (IAP).

DESIGN

Retrospective cohort study of 2909 mother-child pairs.

SETTING

Taixing People's Hospital in Eastern China.

PARTICIPANTS

Term infants born 2018-2019, followed longitudinally from birth to 2 years.

EXPOSURES

The GBS-IAP was defined as therapy with intravenous penicillin G or ampicillin or cefazolin ≥ 4 h prior to delivery to the mother. Reference infants were defined as born without or with other intrapartum antibiotic exposure.

OUTCOMES

The logistic regression models were employed to analyze the effect of intrapartum GBS prophylaxis on AD in 2-year-old children during delivery. Analysis was a priori stratified according to the mode of delivery and adjusted for relevant covariates.

RESULTS

The cohorts showed that preventive GBS-IAP was potentially associated with increased incidence of AD in children delivered vaginally according to logistic regression models before and after covariate-adjusted treatment (OR: 6.719,95% CI: 4.730-9.544,P < 0.001;aOR: 6.562,95% CI: 4.302-10.008, P < 0.001).

CONCLUSION

Prophylactic treatment of intrapartum GBS may raise the risk of AD in vaginally delivered children. These findings highlight the need to better understand the risk between childhood AD and current GBS-IAP intervention strategies.

Use of Dexpanthenol for Atopic Dermatitis—Benefits and Recommendations Based on Current Evidence

Background: Atopic dermatitis (AD) is an inflammatory skin disease of multiple phenotypes and endotypes, and is highly prevalent in children. Many people of all ages, including active adolescents, pregnant women, and the elderly, suffer from AD, experiencing chronicity, flares, and unexpected relapse. Dexpanthenol has multiple pharmacological effects and has been employed to treat various skin disorders such as AD. We aimed to summarize the up-to-date evidence relating to dexpanthenol and to provide a consensus on how to use dexpanthenol effectively for the treatment of AD. Methods: The evidence to date on the application and efficacy of dexpanthenol in AD was reviewed. The literature search focused on dexpanthenol use and the improvement of skin barrier function, the prevention of acute flares, and its topical corticosteroid (TCS) sparing effects. Evidence and recommendations for special groups such as pregnant women, and the effects of dexpanthenol and emollient plus in maintenance therapy, were also summarized. Results: Dexpanthenol is effective and well-tolerated for the treatment of AD. Dexpanthenol improves skin barrier function, reduces acute and frequent flares, has a significant TCS sparing effect, and enhances wound healing for skin lesions. Conclusion: This review article provides helpful advice for clinicians and patients on the proper maintenance treatment of AD. Dexpanthenol, as an active ingredient in ointments or emollients, is suitable for the treatment and maintenance of AD. This paper will guide dermatologists and clinicians to consider dexpanthenol as a treatment option for mild to moderate AD.

Global Burden, Incidence and Disability-Adjusted Life-Years for Dermatitis: A Systematic Analysis Combined With Socioeconomic Development Status, 1990–2019

Background

Dermatitis is an important global health problem that not only affects social interaction and physical and mental health but also causes economic burden. Health problems or distress caused by dermatitis may be easily overlooked, and relevant epidemiological data are limited. Therefore, a better understanding of the burden of dermatitis is necessary for developing global intervention strategies.

Methods

All data on dermatitis, including atopic dermatitis (AD), contact dermatitis (CD) and seborrhoeic dermatitis (SD), were obtained from the Global Burden of Disease 2019 (GBD2019) database. The extracted age-standardized incidence rates (ASIR) and disability-adjusted life-years (DALYs) rates (ASDR) data were analysed by stratification, including by sex, country or region, and sociodemographic index (SDI) indicators. Finally, we analysed the correlation between the global burden of dermatitis and socioeconomic development status.

Results

According to the GBD 2019 estimate, the ASIR and ASDR for the three major types of dermatitis in 2019 were 5244.3988 (95% CI 4551.7244–5979.3176) per 100,000 person-years and 131.6711 (95% CI 77.5876–206.8796) per 100,000 person-years. The ASIR and ASDR of atopic dermatitis, contact dermatitis and seborrhoeic dermatitis are: Incidence (95%CI,per 100,000 person-years), 327.91 (312.76-343.67), 3066.04 (2405.38-3755.38), 1850.44 (1706.25- 1993.74); DALYs (95%CI, per 100,000 person-years), 99.69 (53.09-167.43), 28.06 (17.62-41.78), 3.93 (2.24-6.25). In addition, among the three dermatitis types, the greatest burden was associated with AD. According to the ASDR from 1990 to 2019, the burden of dermatitis has exhibited a slow downward trend in recent years. In 2019, the ASIR showed that the USA had the greatest burden, while the ASDR showed that Asian countries (such as Japan, Mongolia, Kazakhstan, and Uzbekistan) and some European countries (France, Estonia) had the greatest burden. According to SDI stratification and the three major dermatitis types, high ASIR and ASDR corresponded to high SDI areas (especially for AD).

Conclusion

The burden of dermatitis is related to socioeconomic development status, especially for AD, which is positively correlated with the SDI. The results based on GBD2019 data are valuable for formulating policy, preventing and treating dermatitis and reducing the global burden of dermatitis.

Atopic dermatitis: molecular, cellular, and clinical aspects

Atopic dermatitis (AD) is a complicated, inflammatory skin disease, which numerous genetic and environmental factors play roles in its development. AD is categorized into different phenotypes and stages, although they are mostly similar in their pathophysiological aspects. Immune response alterations and structural distortions of the skin-barrier layer are evident in AD patients. Genetic makeup, lifestyle, and environment are also significantly involved in contextual factors. Genes involved in AD-susceptibility, including filaggrin and natural moisturizing, cause considerable structural modifications in the skin's lipid bilayer and cornified envelope. Additionally, the skin's decreased integrity and altered structure are accompanied by biochemical changes in the normal skin microflora's dysbiosis. The dynamic immunological responses, genetic susceptibilities, and structural modifications associated with AD's pathophysiology will be extensively discussed in this review, each according to the latest achievements and findings.

Effects of ambient temperature on outpatient visits for dermatitis in Xinxiang, China: a time-series analysis

Previous studies have reported regional variations in the relationship between ambient temperature and dermatitis, which therefore remain inconclusive. This study aimed to understand the short-term effects of ambient temperature in outpatients with dermatitis in Xinxiang. Routine data of dermatitis outpatient visits between January 1, 2015, and December 31, 2018 were acquired from the First Affiliated Hospital of Xinxiang Medical University. A distributed lag nonlinear model (DLNM) in combination with a generalized additive model (GAM) was applied to investigate the acute impact of ambient temperature on dermatitis outpatients. Two stratified analyses based on age and sex were conducted to explore their potential modification effects. A total of 18,064 dermatitis outpatient records were retrieved during the study period. The relationship between ambient temperature and dermatitis outpatients was found to be nonlinear; exposure-response curves were approximately "J" shaped. The risk of dermatitis outpatient increased with a corresponding elevation in temperature from 11.5 to 27.5°C. However, the significance was lost when the temperature exceeded the given range. Stratified analysis demonstrated higher sensitivity to temperature in females than in males, and the young groups (<15 years) might be sensitive to heat temperature. This study provides first-hand epidemiological evidence demonstrating a higher risk of dermatitis outpatient visits associated with moderately higher temperatures. The outcomes of this study create awareness among citizens to take the necessary precautions to prevent the adverse effects of moderate heat temperature during early summer and autumn seasons.

Classifying atopic dermatitis: a systematic review of phenotypes and associated characteristics

Atopic dermatitis is a heterogeneous disease, accompanied by a wide variation in disease presentation and the potential to identify many phenotypes that may be relevant for prognosis and treatment. We aimed to systematically review previously reported phenotypes of atopic dermatitis and any characteristics associated with them. Ovid EMBASE, Ovid MEDLINE and Web of Science were searched from inception till the 12th of February 2021 for studies attempting to classify atopic dermatitis. Primary outcomes are atopic dermatitis phenotypes and characteristics associated with them in subsequent analyses. A secondary outcome is the methodological approach used to derive them. In total, 8,511 records were found. By focusing only on certain clinical phenotypes, 186 studies were eligible for inclusion. The majority of studies were hospital-based (59%, 109/186) and cross-sectional (76%, 141/186). The number of included patients ranged from seven to 526,808. Data-driven approaches to identify phenotypes were only used in a minority of studies (7%, 13/186). Ninety-one studies (49%) investigated a phenotype based on disease severity. A phenotype based on disease trajectory, morphology and eczema herpeticum was investigated in 56 (30%), 22 (12%) and 11 (6%) studies, respectively. Thirty-six studies (19%) investigated morphological characteristics in other phenotypes. Investigated associated characteristics differed between studies. In conclusion, we present an overview of phenotype definitions used in literature for severity, trajectory, morphology and eczema herpeticum, including associated characteristics. There is a lack of uniform and consistent use of atopic dermatitis phenotypes across studies.

Prevention of Atopic Dermatitis in Mice by Lactobacillus Reuteri Fn041 Through Induction of Regulatory T Cells and Modulation of the Gut Microbiota

SCOPE

The development of atopic dermatitis (AD) in infants is closely related to the lagging development of intestinal microbiota, including that inoculated by breast milk bacteria, and immune development. Lactobacillus reuteri Fn041 is a secretory immunoglobulin A (sIgA) -coated bacterium derived from human milk.

METHODS AND RESULTS

We intervened with L. reuteri Fn041 in maternal and offspring BALB/C mice during late gestation and lactation and after weaning of the pups, respectively. AD was then induced with MC903. L. reuteri Fn041 significantly suppressed AD symptoms such as skin swelling, mast cell and eosinophil infiltration. This effect was attributed to the regulation of the systemic Th1 and Th2 cytokine ratios and the promotion of CD4⁺ CD25⁺ Foxp3⁺ regulatory T cell proliferation in mesenteric lymph nodes. It is also associated with the regulation of intestinal microbiota, particularly promoting Lactobacillus and Akkermansia.

CONCLUSIONS

Our study strengthens the understanding that breast milk-derived sIgA coated potential probiotics are involved in the development of infant intestinal microbiota, thus promoting immune development and preventing allergic diseases, and expanding the knowledge of breast milk sIgA and bacterial interactions on infant immune development. This article is protected by copyright. All rights reserved.

Maternal serum 25-hydroxyvitamin D levels and infant atopic dermatitis: A prospective cohort study

BACKGROUND

Maternal vitamin D status during pregnancy has been linked with the risk of atopic dermatitis (AD) in children, while the results were inconsistent. The objective of this study was to assess the potential association.

METHODS

Serum 25-hydroxyvitamin D (25(OH)D) levels were measured in pregnant women from the birth cohort MKFOAD. Infant AD was diagnosed according to Williams' criteria. Multivariate logistic regression model was used to examine the association of maternal serum 25(OH)D levels in the first, second, and third trimester of gestation with the risk of infant AD at first year of age.

RESULTS

In total, 121 (26.5%) of 456 infants developed AD prior to 1 year of age. In general, higher maternal serum 25(OH)D levels throughout pregnancy were associated with increased risks of AD in infants prior to 1 year of age in multivariate logistic regression models, with borderline statistical significance in the first (per ln unit increase: adjusted OR = 1.93, 95% CI: 0.96, 3.88) and second (per ln unit increase: adjusted OR = 1.72, 95% CI: 0.93, 3.19) trimester. Multivariate logistic regression models using categorical variables of maternal 25(OH)D levels by tertiles showed similar results: Infants born to mothers with serum 25(OH)D levels in the highest tertile had higher risk of AD than those with 25(OH)D in the lowest tertile.

CONCLUSIONS

The present study found some evidence supporting that higher maternal 25(OH)D levels during pregnancy increased the risk of infant AD. However, the clinical implication of the findings should be limited for those with blood levels over the recommendations.

Dupilumab pharmacokinetics in Chinese healthy subjects and patients with atopic dermatitis: Results of two randomized, double-blind, placebo-controlled studies

BACKGROUND

Dupilumab, a fully human monoclonal antibody targeting IL-4Rα, has demonstrated rapid and sustained improvements in clinical outcomes in patients with atopic dermatitis (AD), asthma, and chronic rhinosinusitis with nasal polyps.

METHODS

In a phase 1, double-blind, ascending-dose study, 30 healthy Chinese adults were randomized to single subcutaneous doses of dupilumab 200, 300, 600 mg, or placebo. In a phase 3, double-blind study, 165 Chinese adults with AD were randomized to dupilumab 300 mg or placebo every 2 weeks.

RESULTS

Following single doses of dupilumab 200, 300, and 600 mg in the phase 1 study, mean serum maximum concentrations (C_max) were 25.4 ± 4.0, 37.2 ± 14.5, and 77.3 ± 19.0 mg/L, respectively. For a 1.5-fold increase in dupilumab dose, 1.31-, 1.73-, and 1.66-fold increases in C_max, area under the curve to real time (AUC_last), and extrapolated to infinity (AUC) were observed, respectively, while a 2-fold dose increase resulted in 2.17-, 2.81-, and 2.80-fold increases, respectively. In the phase 3 study, mean dupilumab trough concentrations were 78.8 ± 32.0 and 86.4 ± 33.6 mg/L at weeks 12 and 16, respectively.

CONCLUSIONS

C_max increased approximately proportionally to dose, while AUC and AUC_last increased greater than proportionally. Dupilumab pharmacokinetics were generally comparable between Chinese and non-Asian healthy subjects (single dose) and between Chinese and non-Asian AD patients (repeated doses), with differences accounted for by body weight. As differences in exposure by weight are unlikely to be clinically relevant based on late-stage study results, no dose adjustment by ethnic origin or weight is required.

Update on the Pathogenesis and Therapy of Atopic Dermatitis

Atopic dermatitis (AD) is a common inflammatory skin disorder characterized by recurrent eczematous lesions and intense itch. Although it most often starts in infancy and affects children, it is also highly prevalent in adults. In this article, the main aspects of AD have been updated, with a focus on the pathogenetic and therapeutic aspects. The pathogenesis of AD is complex, and it is evident that a strong genetic predisposition, epidermal dysfunction, skin microbiome abnormalities, immune dysregulation, and the neuroimmune system are critical in AD development. Mutations in the genes associated with disrupted epidermal barrier, exaggerated pathological inflammation and inadequate antimicrobial peptides can promote enhanced Th2 inflammation and mediate pruritus. Current understanding of etiology highlights gut microbial diversity, NK cell deficiency, and different immunological phenotype with age and race. For topical anti-inflammatory treatment for mild-to-severe AD, phosphodiesterase 4 inhibitors (PDE-4), JAK inhibitors, and microbiome transplantation with Roseomonas mucosa provided more management selections. The treatment of moderate-to-severe AD has been limited to merely symptomatic and relatively nonspecific immunosuppressive approaches. In-depth understanding of the pathogenesis of AD has led to the development of innovative and targeted therapies, such as biologic agents targeting interleukin (IL)-4, IL-13 and JAK/STAT inhibitors. Other potential therapeutic agents for AD include agents targeting the T helper (Th) 22 and Th17/IL23 pathway. Antipruritic therapy and complementary probiotics therapy have also been reviewed.

Breast milk flora plays an important role in infantile eczema: cohort study in Northeast China

AIMS

Infantile eczema, usually coupled with a range of hypersensitive phenotypes, has come into notice with its rising prevalence and unclear pathogenesis. Recent studies show close ties between eczema and an infant's intestinal flora. To gain a further understanding of the interactions between microbiota and eczema, we studied the breast milk flora as a new factor and present the links among breast milk flora, infant intestinal flora and infantile eczema through a cohort study in Northeast China.

METHODS AND RESULTS

Fifty-two families were recruited with either an eczema or healthy infant younger than 6 months. Analysis and predictions using amplicon sequencing of microbiota found that Bifidobacterium and Bacteroidetes were enriched in healthy and eczema infant stools, respectively, consistent with previous reports. For breast milk flora, more 'positive' bacteria such as Akkermansia were enriched in breast milk from healthy infants' mothers. Further, higher bacterial delivery efficiencies were found in pairs of breast milk flora and infants' stool flora of families with eczema infants compared with families with healthy infants. Bacteroidetes, a widely known indicator of eczema, was found delivered more in eczema pairs. Further metagenomic predictions revealed that the breast milk microbiota participated significantly less in metabolism and immune system pathways, particularly in antigen processing and presentation and in Th17 cell-related pathways.

CONCLUSIONS

In conclusion, as with other components of breast milk, the breast milk microbiota closely associates with infants' health via mother-infant bacterial delivery and metabolic functions.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our research aimed to fill the gap between the eczema and breast milk flora and describe the connections among breast milk and intestinal flora and eczema.

Maternal periconceptional folate status and infant atopic dermatitis: A prospective cohort study

BACKGROUND

Maternal folate status is linked with the risk of allergic disorders including atopic dermatitis (AD) in children, but findings remain inconclusive. We aim to assess the relationship between maternal folate status in early gestation and early-onset infant AD, based on a prospective mother-child cohort study.

METHODS

Pregnant women were recruited at 12-14 weeks of gestation. Red blood cell folate (RBC folate) and serum folate concentrations were examined at enrollment. Periconceptional folic acid supplementation was investigated through a self-administered questionnaire. The primary outcome was AD incidence before 6 months of age, diagnosed according to Williams' criteria. Multivariate logistic regression was used to evaluate associations of maternal folate status with infant AD by adjusting parental and child covariates.

RESULTS

In total, 107 (23.4%) of 458 infants developed AD before 6 months, with more male infants affected (P = .002). Higher maternal RBC folate levels (per 100 ng/mL) were associated with an increased risk of AD (adjusted odds ratio [aOR] 1.16, 95% confidence interval [CI] 1.04-1.31). An RBC folate level ≥620 ng/mL was associated with increased infant AD by 91% (aOR 1.91, 95% CI 1.09-3.36). However, associations were not observed for maternal serum folate at early gestation or periconceptional folic acid supplement intakes.

CONCLUSIONS

We provide the first evidence that higher maternal RBC folate concentrations during early gestation are associated with increased early-onset infant AD. Our findings support the importance of maintaining appropriate folate levels during the periconceptional period to reduce the risk of AD in infants.

Distinct clinical features and serum cytokine pattern of elderly atopic dermatitis in China

BACKGROUND

Elderly atopic dermatitis (AD) is a newly defined subtype of AD stratified by age-related clinical pictures.

OBJECTIVES

To analyse the clinical features and molecular profile of elderly AD patients in China, comparing with infantile, childhood and adolescent/adult AD.

METHODS

A total of 1312 patients diagnosed by Hanifin and Rajka diagnostic criteria of AD from Huashan Hospital, Shanghai, China, were divided into four groups by age (2-18, 19-40, 41-60 and >60 years), and clinical features were evaluated by questionnaire and physical examination. Serum total IgE, eosinophil counts and various cytokines were further analysed in some of the patients and healthy controls.

RESULTS

Elderly AD showed significantly higher male/female ratio and rural/urban ratio than other age groups, and more than half of elderly AD first appeared after 60 years old. Skin lesions of elderly AD were more often seen in the trunk and extensor sites of the extremities. Level of serum IgE and eosinophil counts were significantly lower in elderly AD than those in other age groups. Serum levels of IL-4, TARC, IL-17A, IL-6, IL-22, IL-33 and TSLP were significantly higher in elderly AD patients than those of healthy controls, indicating a mixed Th2/Th17/Th22 inflammation.

CONCLUSIONS

Elderly AD demonstrated unique clinical characteristics compared with other age groups and showed mixed Th2/Th17/Th22 skewing, indicating a unique pathogenesis for elderly AD.