Effects of Early Diet on the Prevalence of Allergic Disease in Children: A Systematic Review and Meta-Analysis

Recent evidence suggests that the timing of introduction, types, and amounts of complementary foods/allergenic foods may influence the risk of allergic disease. However, the evidence has not been updated and comprehensively synthesized. The Cochrane Library, EMBASE, Web of Science, and PubMed databases were searched from the inception of each database up to 31 May 2023 (articles prior to 2000 were excluded manually). Statistical analyses were performed using RevMan 5. The GRADE approach was followed to rate the certainty of evidence. Compared with >6 mo, early introduction of eggs (≤6 mo of age) might reduce the risk of food allergies in preschoolers aged <6 y (odds ratio [OR], 0.65; 95% confidence interval [CI], 0.53, 0.81), but had no effect on asthma or atopic dermatitis (AD). Consumption of fish at 6-12 mo might reduce the risk of asthma in children (aged 5-17 y) compared with late introduction after 12 mo (OR, 0.61; 95% CI: 0.52, 0.72). Introduction of allergenic foods for ≤6 mo of age, compared with >6 mos, was a protective factor for the future risk (children aged ≤10 y) of AD (OR, 0.93; 95% CI: 0.89, 0.97). Probiotic intervention for infants at high risk of allergic disease significantly reduced the risk of food allergy at ages 0-3 y (OR, 0.72; 95% CI: 0.56, 0.94), asthma at 6-12 y (OR, 0.61; 95% CI: 0.41, 0.90), and AD at aged <6 y (3-6 y: OR, 0.70; 95% CI: 0.52, 0.94; 0-3 y: OR, 0.73; 95% CI: 0.59, 0.91). Early introduction of complementary foods or the high-dose vitamin D supplementation in infancy was not associated with the risk of developing food allergies, asthma, or AD during childhood. Early introduction to potential allergen foods for normal infants or probiotics for infants at high risk of allergies may protect against development of allergic disease. This study was registered at PROSPERO as CRD42022379264.

Global epidemiology of atopic dermatitis: a comprehensive systematic analysis and modelling study

BACKGROUND

Atopic dermatitis (AD) is the leading cause of the global burden from skin disease; no study has provided global and country-specific epidemiological estimates of AD.

OBJECTIVES

To quantify global, regional and country-specific estimates of the epidemiology of AD.

METHODS

A comprehensive search for epidemiological studies in AD was conducted in four electronic databases (PubMed, Embase, Web of Science and China National Knowledge Infrastructure). A Bayesian hierarchical linear mixed model was constructed to calculate epidemiological estimates of AD considering the heterogeneity of regions, countries, type of diagnoses and age strata.

RESULTS

In total, 344 studies met the inclusion criteria. Incidence varied substantially with the location and age of the surveyed participants. The global prevalence of AD and the population affected by AD were estimated to be 2.6% [95% uncertainty interval (UI) 1.9-3.5] and 204.05 million people, respectively. Around 101.27 million adults and 102.78 million children worldwide have AD, corresponding to prevalence rates of 2.0% (95% UI 1.4-2.6) and 4.0% (95% UI 2.8-5.3), respectively. Females were more likely to suffer from AD than males: the global prevalence of AD in females was 2.8% (95% UI 2.0-3.7%) and affected 108.29 million people, while in males the corresponding estimates were 2.4% (95% UI 1.7-3.3%) and 95.76 million people.

CONCLUSIONS

Epidemiological AD data are lacking in 41.5% of countries worldwide. The epidemiology of AD varies substantially with age and sex and is distributed unequally across geographical regions.

Mode of delivery and offspring atopic dermatitis in a Swedish nationwide study

BACKGROUND

Atopic dermatitis is a common chronic childhood disease associated with significant morbidity and healthcare costs. There is a known association between caesarean section and asthma, but the relationship between caesarean section and offspring atopic dermatitis remains uncertain.

METHODS

We conducted a register-based nationwide cohort study including children born in Sweden between January 2006 and December 2018. Data on health and socioeconomic variables were extracted from the national registers for children aged ≤5 years. Time-to-event analyses were used to calculate hazard ratios (HR) with 95% confidence intervals (CI) adjusting for confounders and familial factors.

RESULTS

1,399,406 children were included (6,029,542 person-years at risk). Atopic dermatitis was observed in 17.2% of the 1,150,896 children born by vaginal delivery and 18.3% of the 248,510 born by caesarean section. The mean age of onset of atopic dermatitis was 2.72 years (SD 1.8). Birth by caesarean section was associated with a higher risk of atopic dermatitis (adj-HR 1.12, 95% CI: 1.10-1.14). A higher risk of atopic dermatitis was found in children born by instrumental vaginal delivery (adj-HR 1.10, 1.07-1.13); emergency caesarean section (adj-HR 1.12, 1.10-1.15), and elective caesarean section (adj-HR 1.13, 1.10-1.16) than uncomplicated vaginal delivery in children <1 year of age. Similar hazards were observed in those ≥1 year of age. In sibling control analysis, greater risks remained in children aged <1 year but not in age ≥1 year.

CONCLUSIONS

In our study population, it was observed that children born by caesarean section or instrumental vaginal delivery were at higher risk of early childhood atopic dermatitis. Although familial confounding attenuates the risk in children aged ≥1 year, this was not observed in the first year of life.

A programme of research to set priorities and reduce uncertainties for the prevention and treatment of skin disease

Background

Skin diseases are very common and can have a large impact on the quality of life of patients and caregivers. This programme addressed four diseases: (1) eczema, (2) vitiligo, (3) squamous cell skin cancer (SCC) and (4) pyoderma gangrenosum (PG).

Objective

To set priorities and reduce uncertainties for the treatment and prevention of skin disease in our four chosen diseases.

Design

Mixed methods including eight systematic reviews, three prioritisation exercises, two pilot randomised controlled trials (RCTs), three feasibility studies, two core outcome initiatives, four funding proposals for national RCTs and one completed national RCT.

Setting

Secondary care, primary care and the general population.

Participants

Patients (and their caregivers) with eczema, vitiligo, SCC and PG, plus health-care professionals with an interest in skin disease.

Interventions

Our three intervention studies included (1) barrier enhancement using emollients from birth to prevent eczema (pilot RCT); (2) handheld narrowband ultraviolet light B therapy for treating vitiligo (pilot RCT); and (3) oral ciclosporin (Neoral®, Novartis Pharmaceuticals) compared with oral prednisolone for managing PG (pragmatic national RCT).

Results

Systematic reviews included two overarching systematic reviews of RCTs of treatments for eczema and vitiligo, an umbrella review of systematic reviews of interventions for the prevention of eczema, two reviews of treatments for SCC (one included RCTs and the second included observational studies), and three reviews of outcome measures and outcome reporting. Three prioritisation partnership exercises identified 26 priority areas for future research in eczema, vitiligo and SCC. Two international consensus initiatives identified four core domains for future eczema trials and seven core domains for vitiligo trials. Two pilot RCTs and three feasibility studies critically informed development of four trial proposals for external funding, three of which are now funded and one is pending consideration by funders. Our pragmatic RCT tested the two commonly used systemic treatments for PG (prednisolone vs. ciclosporin) and found no difference in their clinical effectiveness or cost-effectiveness. Both drugs showed limited benefit. Only half of the participants’ ulcers had healed by 6 months. For those with healed ulcers, recurrence was common (30%). Different side effect profiles were noted for each drug, which can inform clinical decisions on an individual patient basis. Three researchers were trained to PhD level and a dermatology patient panel was established to ensure patient involvement in all aspects of the programme.

Conclusions

Findings from this programme of work have already informed clinical guidelines and patient information resources. Feasibility studies have ensured that large national pragmatic trials will now be conducted on important areas of treatment uncertainty that address the needs of patients and the NHS. There is scope for considerable improvement in terms of trial design, conduct and reporting for RCTs of skin disease, which can be improved through wider collaboration, registration of trial protocols and complete reporting and international consensus over core outcome sets. Three national trials have now been funded as a result of this work. Two international initiatives to establish how best to measure the core outcome domains for eczema and vitiligo are ongoing.

Trial registration

Current Controlled Trials Barrier Enhancement for Eczema Prevention (BEEP) (ISRCTN84854178 and NCT01142999), Study of Treatments fOr Pyoderma GAngrenosum Patients (STOP GAP) (ISRCTN35898459) and Hand Held NB-UVB for Early or Focal Vitiligo at Home (HI-Light Pilot Trial) (NCT01478945).

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 4, No. 18. See the NIHR Journals Library website for further project information.

Gamma-linolenic acid levels correlate with clinical efficacy of evening primrose oil in patients with atopic dermatitis

Introduction

Atopic dermatitis (AD) has been related to a deficiency of delta-6-desaturase, an enzyme responsible for the conversion of linoleic acid to gamma-linolenic acid (GLA). Evening primrose oil (EPO) contains high amounts of GLA. Therefore, this study investigated whether EPO supplementation results in an increase in plasma GLA and its metabolite dihomo-gamma-linolenic acid (DGLA) correlating with clinical improvement of AD, assessed by the SCORing Atopic Dermatitis (SCORAD) index.

Methods

The open study included 21 patients with AD. EPO (4–6 g) was administered daily for 12 weeks. Before treatment, and 4 and 12 weeks after initiation of EPO supplementation, objective SCORAD was assessed and plasma concentrations of GLA and DGLA were determined by gas chromatography.

Results

A significant increase in plasma GLA and DGLA levels and a decrease in the objective SCORAD were observed 4 and 12 weeks after initiation of EPO treatment. In the per-protocol population (n = 14), a significant inverse correlation between the changes in plasma GLA levels and SCORAD was found (P = 0.008).

Conclusion

The clinical disease activity under EPO treatment correlates with the individual increase in plasma GLA levels. Thus, the results of this pilot study indicate that an increase in plasma GLA might be used as predictive parameter for responsiveness of AD to EPO therapy.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-014-0093-0) contains supplementary material, which is available to authorized users.

The natural history of cow's milk allergy in north-eastern Poland

PURPOSE

The rate of cow's milk allergy diminishes with age. There is not enough information concerning geographical trends in persistent cow's milk allergy in children. The objective of the study was to evaluate the prevalence of persistent cow's milk allergy in children previously diagnosed with IgE-mediated cow's milk allergy (CMA).

MATERIAL/METHODS

Diagnosis of cow's milk allergy was established by a medical history of symptoms associated with exposure to cow's milk, positive skin prick tests with cow's milk, the presence of milk-specific IgE, and by a positive double- or single-blind placebo-controlled food challenge with milk confirmed by a positive open-controlled milk challenge. A second oral challenge was performed after at least one year of a milk-free diet and children with a positive oral milk rechallenge were diagnosed as having a persistent CMA.

RESULTS

Two hundred ninety-one children, 2-14 years of age (mean 5.30±3.16 years, 95% CI, 5.02-5.62 years) completed the study. Persistent CMA was diagnosed in 79 patients (27.1%). Two hundred twelve children (72.9%) outgrew their allergy to cow's milk at a mean age of 5 years after an average time of 16.4±0.8 months on an elimination diet. Eighty percent of children below 3 years of age became milk tolerant. Milk-specific IgE (p=0.018) and history of paternal bronchial asthma and/or rhinitis (p=0.020) were associated with persistence of cow's milk allergy in regression analysis.

CONCLUSIONS

An age above 3 years, as well as features of atopy, individual and familial, may be associated with a risk of delayed tolerance to milk in children.

How should an incident case of atopic dermatitis be defined? A systematic review of primary prevention studies

BACKGROUND

Eczema prevention is now an active area of dermatologic and allergy research. Defining an incident case is therefore a prerequisite for such a study.

OBJECTIVE

We sought to examine how an incident case of atopic dermatitis was defined in previous atopic dermatitis prevention studies in order to make recommendations on a standard definition of new atopic dermatitis cases for use in future prevention trials.

METHODS

We conducted a systematic review of controlled interventional atopic dermatitis prevention studies by using searches of MEDLINE and Cochrane databases for studies published from 1980 to the end of January 2011. Studies that included atopic dermatitis as a secondary outcome, such as asthma prevention trials, were included.

RESULTS

One hundred two studies were included in the final analysis, of which 27 (26.5%) did not describe any criteria for defining an incident case of atopic dermatitis. Of the remaining 75 studies with reported disease criteria, the Hanifin-Rajka criteria were the most commonly used (28 studies). A disease definition unique to that particular study (21 studies) was the second most commonly used disease definition, although the sources for such novel definitions were not cited.

CONCLUSIONS

The results from this systematic review highlight the need for improved reporting and standardization of the definition used for an incident case in atopic dermatitis prevention studies. Most prevention studies have used disease definitions such as the Hanifin-Rajka criteria that include disease chronicity. While acceptable for cumulative incidence outcomes, inclusion of disease chronicity precludes the precise measurement of disease onset. We propose a definition based on existing scientific studies that could be used in future prospective studies.

Comorbidity in Atopic Dermatitis

The negative impact of atopic dermatitis (AD) often extends beyond the skin. Children with AD experience increased rates of infectious, mental health, and allergic diseases compared to their non-atopic peers. The mechanisms underlying these associations remain elusive. New insights from genetic and epidermal research pinpoint the skin barrier as a primary initiator of AD. Epicutaneous sensitization represents an intriguing new model which links a disrupted skin barrier to the later development of IgE-mediated diseases in patients with AD. Recent epidemiological studies have identified new comorbidities linked to AD as well, including several mental health disorders and obesity. This manuscript reviews the recent literature regarding both classic and newly described AD comorbidities.

Long-term reduction in local inflammation by a lipid raft molecule in atopic dermatitis

BACKGROUND

The complex pathogenesis of atopic dermatitis (AD) is guided by cell surface receptor-mediated signal transduction regulated in lipid rafts. Miltefosine is a raft-modulating molecule targeting cell membranes. With this controlled clinical study, the clinical and immunomodulatory efficacy of miltefosine was investigated in patients with AD in comparison with a topical corticosteroid treatment.

METHODS

Sixteen patients with AD were treated topically with miltefosine and hydrocortisone localized on representative AD target lesions for 3 weeks. To assess the clinical efficacy, the three item severity (TIS) score was evaluated before, during and after treatment as well as after 4-week-follow-up period. To study the anti-inflammatory effect of miltefosine on the cellular T cell pattern, skin biopsies were analysed before and after treatment.

RESULTS

The TIS score dropped in both groups significantly after treatment. A carry-over effect was exclusively seen for miltefosine after discontinuing the treatment. These findings were substantiated by thermographic imaging with a significant decrease in the maximum temperature (T(max)) after miltefosine application (P = 0.034, DeltaT(max) = 1.7 degrees C [2.1-3.9]). Immunohistochemically, a reduction in lesional CD4(+)-infiltrating T cells was observed in both treatments. Moreover, increased FoxP3(+) cells were present in the skin after miltefosine treatment (before 5.4% [1.9-9.8], after 6.2% [3.5-9.5]).

CONCLUSION

We demonstrate that miltefosine is locally active in patients with AD and led to a sustained clinical improvement in local skin inflammation. Moreover, the increased frequency of FoxP3(+) cells in the skin of patients with AD suggests its immunomodulatory properties.

Useful tools for the management of atopic dermatitis

Eczema, frequently named atopic dermatitis, is the most frequent chronic skin disease of early childhood, with a high prevalence in industrialized countries and a relapsing-remitting course that is responsible for a serious burden on affected children and their families. Even though most facets of this disease are nowadays well known and numerous guidelines are available, some confusion still exists regarding certain aspects. First, several names have been proposed for the disorder. We suggest that the name and definition adopted by the World Allergy Organization should be used: 'eczema,' divided into 'atopic,' when an allergic sensitization can be demonstrated, and 'non-atopic,' in the absence of sensitization. Several diagnostic criteria have been proposed, but at present the two most reliable are the 2003 revision by the American Academy of Dermatology of the Hanifin-Rajka criteria, and those by Williams revised in 2005. To date, 20 different clinical scores have been published to assess the severity; however, only the EASI (Eczema Area and Severity Index), the SCORAD (SCORing Atopic Dermatitis), and the POEM (Patient-Oriented Eczema Measure) seem to have been adequately validated and are recommended for use in clinical practice and trials. The diagnostic tests to identify associated allergy or sensitization include skin-prick tests, determination of the specific IgE in serum using different assays, and atopy patch tests; in the case of suspected food allergy, a food challenge may be necessary to define the diagnosis. To evaluate quality of life, tools exist that allow both the child's and family's impairment to be considered. In addition, several algorithms exist to help decide therapy on a step-wise basis. However, such guidelines and algorithms represent only an aid to the physician and not an obligatory directive, since the ultimate judgment regarding any therapy must be performed by the physician and tailored to individual needs. A clear and validated definition of eczema control would permit better monitoring of the disease, similar to the situation with asthma in recent years. Finally, the review examines the role of special textiles in diminishing Staphylococcus aureus skin superinfection, of house dust-mite avoidance measures, and of educational programs for patients and their families, which may all help improve eczema.

Prevalence of atopic dermatitis and serum IgE values in nursery school children in Ishigaki Island, Okinawa, Japan

There have been many studies of the prevalence of atopic dermatitis (AD), but few population-based epidemiologic studies measure the prevalence in Japan among children aged 5 years and younger. We examined the prevalence of AD, serum total IgE levels and specific IgE antibodies to 10 common allergens among children in Ishigaki Island, Okinawa, Japan in 2001. We also obtained information on the predictability of the U.K. Working Party diagnostic questionnaire criteria for AD in this population. Five hundred and sixty five children aged 5 years and younger were enrolled in this study with informed consent from their parents. The questionnaire of the U.K. Working Party diagnostic criteria for AD was translated into Japanese, and the parents completed the questionnaire sheet. Physical examination and blood sampling were done for all children. Thirty-nine out of the 565 (6.9%) children were diagnosed with AD by physical examination. The total and specific IgE levels were significantly higher in the children with AD than in those without AD. High levels of total IgE were found in 33.3% of the children with AD. A specific IgE to one or more allergens was detected in 64.1% of children with AD. However, a substantial population of children without AD also had high levels of total IgE (12.7%) and a specific IgE to one or more allergens (30.2%), and the increment of total and specific IgE levels was significantly associated with age. The percentage of positive answers to the questionnaire of the U.K. Working Party diagnostic criteria for AD was significantly higher in children with AD (59.0%) than in children without AD (5.3%) (P<0.0001). Its specificity was 94.7%. The false negative rate was 41%. In conclusion, the prevalence of AD was relatively low in children in Ishigaki Island. High levels of total IgE were found in only one third of children with AD under 5 years of age. The Japanese translated form of the questionnaire of the U.K. Working Party diagnostic criteria for AD should be refined to improve its sensitivity.

How atopic is atopic dermatitis?

BACKGROUND

The extent to which the phenotype of atopic dermatitis (AD) is truly atopic has been the subject of much debate.

OBJECTIVE

We sought to systematically evaluate the evidence for the value of measurement of IgE antibodies in diagnosing AD and whether knowledge of IgE sensitization increases clinical diagnostic and predictive ability.

METHODS

We searched Medline from its inception until September 2003. Only studies that measured atopy as either skin prick test positivity or IgE-antibody sensitization to environmental allergens were included within a descriptive analysis. Because the small number of studies of adequate quality did not allow a formal meta-analysis, we assigned strength of evidence according to predefined quality criteria and ranked studies accordingly.

RESULTS

Inclusion of atopy as part of the diagnostic criteria for AD did not enhance the criteria's sensitivity and specificity in relation to the clinical phenotype of AD. The strength of association between atopy and AD varied significantly between hospital studies (47% to 75%; n=14 studies) and was stronger in hospital than in community populations (7.4% to 78%; n=13 studies). Whereas study quality did not have an effect on atopy prevalence in hospital populations, low atopy prevalences in community surveys were seen in less rigidly conducted studies. AD severity was positively associated with the number of positive skin prick test responses or IgE-antibody levels in 7 of 8 studies that measured both. Only one study suggested that IgE-specific sensitization to hen's egg is associated with subsequent development of AD, and 2 studies found that allergen-specific IgE sensitization in patients with AD is a prognostic marker for allergic airway disease in later life. Atopy-associated AD might also have a worse long-term prognosis than AD that is not associated with atopy.

CONCLUSION

Although atopy is clearly associated with AD, the role of IgE sensitization in AD needs further study. Current evidence suggests that up to two thirds of persons with AD are not atopic, which implies that continued use of the term atopic dermatitis is problematic. Longitudinal studies are needed to compare the treatment response and prognosis of IgE-associated and non-IgE-associated AD.

Genetic variants of the IL13 and IL4 genes and atopic diseases in at-risk children

We studied a cohort containing 368 children at high risk of developing atopy and atopic disorders and 540 parents of those children to investigate whether the IL13 Arg130Gln and C-1112 T polymorphisms were associated with these outcomes. We also investigated whether haplotypes consisting of any two polymorphisms of IL13 Arg130Gln, IL13 C-1112 T and IL4 C-589 T were associated with these phenotypes. In 288 white children, the IL13 130Gln allele was associated with atopy (RR=1.9, P=0.047), and with atopic dermatitis (RR=2.5, P=0.014). The associations were confirmed using a family-based test of association (P=0.027 and 0.030, respectively) in all subjects. In white subjects there were associations of haplotypes consisting of IL13 Arg130Gln and IL4 C-589 T with atopic dermatitis (P=0.006) and with atopy (P=0.009). Our data suggest that the IL13 Arg130Gln polymorphism and haplotypes consisting of IL13 Arg130Gln and IL4 C-589 T were associated with the development of atopy and atopic dermatitis at 24 months of age.

Atopic dermatitis: review of immunopathogenesis and advances in immunosuppressive therapy

This paper reviews the theories of the pathogenesis of atopic dermatitis (AD), with a particular emphasis on its immunopathogenesis. The contribution of predisposing factors, immunopathogenic factors and provoking factors in the pathogenesis of AD are considered. Predisposing factors explored in this article include genetics and the disturbance of skin function. Immunopathogenic factors reviewed include T cell dysfunction, biphasic cytokine expression and the role of immunoglobulin E. Provoking factors considered include microbial factors, psychosomatic interactions, contact allergens and irritants, inhalant allergens, food and climate. Immunosuppressive treatments reviewed include cyclosporin, azathioprine, methotrexate, tacrolimus, interferon-gamma, phosphodiesterase inhibitors and pimecrolimus (SDZ ASM 981).

Cow's milk allergy is associated with recurrent otitis media during childhood

To determine whether cow's milk allergy (CMA) in infancy is associated with recurrent otitis media (ROM) or other chronic ear infections, we conducted a cohort study by enrolling 56 milk-allergic and 204 control schoolchildren. We also studied the association between ear problems and different atopic manifestations. A higher proportion of children with CMA had had ROM. defined as at least 15 acute otitis media episodes by the age of 10 years (27%, vs 12%, p = 0.009), and had undergone adenoidectomy and or tympanostomy compared with the controls (48%, vs 28%, p = 0.005). However, this was only true of the children who had developed respiratory atopy. Asthma and/or allergic rhinitis, but not atopic dermatitis, posed a significant risk for ROM, while all the three atopic manifestations enhanced the risk for secretory otitis media. Positive skin prick tests with food, but not with inhaled allergens, tended to be associated with ear problems. In conclusion, we found that children with CMA in infancy, even when properly treated, had experienced significantly more ROM, the risk associating with concomitant development of respiratory atopy.

Biochemical and immunologic mechanisms in atopic dermatitis: new targets for emerging therapies

The immunologic and pharmacophysiologic features of atopic dermatitis have stimulated research seeking to identify relevant effector cells and mediators that characterize chronic skin inflammation. The theory that unifies the various abnormalities associated with atopic dermatitis suggests that hematopoietic cells carrying abnormal genetic expressions of atopy cause clinical disease once they infiltrate the skin and mucosa. The proposed underlying mechanism may be either abnormalities in cyclic nucleotide regulation of marrow-derived cells or allergenic overstimulation that causes secondary abnormalities. The primacy of one mechanism over the other remains unresolved, but this does not obviate their value in identifying two novel therapeutic targets: phosphodiesterase inhibition and immune-intervention alternatives to corticosteroids. New type IV phosphodiesterase inhibitors are proving promising in topical formulations, as are inhibitors of calcineurin, such as FK506 and SDZ ASM 981, an ascomycin macrolactam derivative that in early clinical research appears to offer the potency of a corticosteroid without its adverse side effects. The promising clinical trial profiles of these new topical agents may result in alternative therapies providing potent anti-inflammatory activity without the adverse effects that limit corticosteroid use.

Cataract and aqueous flare levels in patients with atopic dermatitis

PURPOSE

To determine whether cataract in patients with atopic dermatitis is associated with higher levels of aqueous flare or cells.

METHODS

In a prospective study, 35 consecutive patients examined during a 6-month period at the atopic dermatitis service in a university hospital underwent standardized ophthalmologic evaluations including the quantitative measurement of aqueous flare and cells by a laser flare-cell meter.

RESULTS

Seven patients had bilateral cataract with anterior or posterior subcapsular opacities, or both; one patient had similar cataract in one eye and no cataract in the opposite eye; and 27 patients had no cataract in either eye. Fifteen eyes with cataract showed significantly higher levels of aqueous flare (2.1 to 33.9 photon counts per millisecond with a median of 18.0) compared with 55 eyes without cataract (2.4 to 16.0 photon counts per millisecond with a median of 9.2; Mann-Whitney U test, P = .0008). The association of cataract with higher levels of aqueous flare remained significant when only one eye (the right eye) of each patient was chosen for statistical analysis (P = .0024).

CONCLUSION

Higher levels of aqueous flare caused by the breakdown of blood-aqueous barrier may contribute to the formation of cataract in patients with atopic dermatitis.

Growth of herpes simplex type 1 on skin explants of atopic eczema

In a novel approach to looking at why some children with atopic eczema are susceptible to cutaneous herpes simplex virus (HSV) infections, this study evaluates the hypothesis that HSV replicates more easily on eczematous than normal skin. Growth of HSV on eczematous skin explants was compared with growth on explants from three control groups (psoriasis, Darier's disease and normal skin) over a 2-day period. Growth of HSV was significantly less on normal skin than in atopic eczema, psoriasis and Darier's disease. Virus replicated more quickly, and grew to higher titre within 24h, in eczematous and psoriatic explants than in normal skin. A defect in skin barrier function and host defence factors including local cytokine secretion are discussed as possible mechanisms in causing the increased susceptibility of children with atopic eczema to HSV infection.

Allergic and irritant patch test reactions and atopic disease

This study presents a profile of patients with chronic recalcitrant eczematous disease referred by dermatologists for contact allergy evaluation. Allergic contact dermatitis (ACD) and irritant responses were carefully defined, as was the presence or absence of atopy obtained by history. Of 410 patients studied, 44% had no history of atopic disease and 46% were classed as definitely atopic. Among relevant ACD patch test reactors (n = 198), 51.5% had atopy, compared with 40.9% with no atopy but this difference was not significant. Likewise, among atopics (n = 189), 54% had definite, relevant ACD patch test responses while 33.9% had negative ACD (again not significant). Significance was seen in the higher mean number of positive allergic patch tests in the atopic group (2.7 versus 2.0, p = 0.0223). Irritant patch tests were highest among patients with both ACD and atopy (p = 0.0308) and the proportion of irritant responses correlated with increasing numbers of positive ACD tests. We conclude that atopics are at least as likely to have ACD as are non-atopics. Irritancy is increased in these patients with chronic dermatitis and the frequency of irritant reactions correlates with both greater numbers of ACD responses and with presence of atopy.

Reduced interferon-gamma (IFN-gamma) secretion with increased IFN-gamma mRNA expression in atopic dermatitis: evidence for a post-transcriptional defect

Reduced secretion of IFN-gamma in atopic individuals has been implicated in the pathogenesis of disease, though the mechanisms leading to this reduced secretion have not been elucidated. As production of IFN-gamma has been shown to be predominantly regulated by its rate of transcription, expression of IFN-gamma mRNA was examined in atopic children and in age-matched, non-atopic controls by polymerase chain reaction (PCR)-assisted mRNA amplification. Children with atopic dermatitis were found to have constitutive expression of IFN-gamma mRNA in freshly isolated peripheral blood mononuclear cells (PBMC) and in unstimulated PBMC cultures which increased further following stimulation with phorbol myristate acetate (PMA)/Ca in vitro. In contrast, expression of IFN-gamma mRNA in controls was only detected in stimulated cultures, as has been demonstrated previously for normal adults. These findings demonstrate that circulating T cells from atopic children have been activated in vivo, and suggest that T cell activation is a significant component of the inflammatory process in atopic dermatitis. Although expression of IFN-gamma mRNA was increased in the atopic children, secretion was confirmed to be significantly lower than in controls, indicating that the defect(s) underlying reduced IFN-gamma secretion in these individuals lie post-transcriptionally.

Allergic cycle: relationships between asthma, allergic rhinitis, and atopic dermatitis

Details of the symptomatic history of 118 asthmatic patients with allergic rhinitis (AR), 18 asthmatic patients with atopic dermatitis (AD), and 6 asthmatic patients with both AR and AD were investigated. All 142 patients had atopic (64 cases) or mixed-type asthma (78 cases). In 118 (83%) and 66 (46%) of the 142 patients, asthmatic attacks were mainly associated with autumn and the rainy season in Japan, respectively. In 84 (68%) of 124 patients with AR, AR-related symptoms were mainly associated with spring. In 68 patients (55%), AR appeared 1-33 years (mean, 10.5 years) before the initial appearance of asthma. In patients with asthma and AR, 102 (82%) of 124 cases had an inverse relationship between the peak times of symptoms consistent with asthma and AR. In 84 (82%) and 80 (78%) of 102 patients with an inverse relationship between the peak times of symptoms associated with asthma and AR, respectively, episodes of preceding AR and infectious rhinitis were not seen at each asthmatic attack. Of 24 asthmatic patients with AD, 12 (50%) had AD 1-23 years (mean, 14.3 years) after the initial appearance of asthma. In 18 (75%) of 24 patients, an inverse relationship between the peak times of symptoms consistent with asthma and AD was observed. These results have tempted us to consider an allergic cycle theory that asthma may be inactive when AR or AD is active; i.e., one active allergic reaction occurs at only one site among allergic sites of the body, including the bronchi, nasal mucosa, and skin.

Increased interleukin 6 production by T cells derived from patients with atopic dermatitis

Many immunologic aspects of atopic dermatitis have been studied, but basic pathobiologic mechanisms of this disease remain unknown. In this study, we measured the production of interleukin-6 (IL-6) by peripheral blood T cells and monocytes from patients with atopic dermatitis in comparison to normal control subjects and patients with chronic psoriasis. We found that peripheral blood T cells isolated from patients with atopic dermatitis produced significantly higher levels of IL-6 (36.1 +/- 5.1 units/ml, n = 22) than T cells derived from either normal subjects (12.6 +/- 1.9 units/ml, n = 22) or patients with chronic psoriasis (26.7 +/- 4.1 units/ml, n = 7). T-cell activation was also measured in the patients with atopic dermatitis by soluble serum IL-2 receptor levels and were found to be significantly higher (623.7 +/- 8.1 units/ml, n = 8) than normal subjects (357.2 +/- 26.0 units/ml, n = 8). In contrast to the increased production of IL-6 by T cells in atopic dermatitis, there was no significant difference in the IL-6 production by peripheral blood monocytes derived from patients with atopic dermatitis compared to normal subjects. Thus, peripheral blood T cells derived from patients with AD spontaneously produce increased amounts of IL-6 compared to T cells from normal subjects, which may reflect the increased activation state of T cells in atopic dermatitis. These data support the concept that activated T cells or subsets of T cells may be important effector cells in mediating inflammatory activity in atopic disease.

Contact dermatitis and its relationship to atopy in workers on the Polish State Railways

Clinical examinations, patch tests and prick tests were carried out in a group of railwaymen. Only 3 had both eczema and atopy. Prick tests were positive in a high proportion of subjects, including both those with eczema and controls.

Recent advances in the pathogenesis of atopic dermatitis

Atopic dermatitis (AD) is an inflammatory skin disorder affecting 5%-10% of children. Although basic mechanisms remain largely speculative, recent studies on the pathogenesis have elucidated new insights, pointing to the importance of food and inhalant allergens. The pathogenesis of AD can be more easily explained by the model of late skin reaction occurring after mast cell activation. The present report highlights some of the more recent developments in the mechanisms of AD which can be important in understanding and treating this troublesome disease.

Ulcerative blepharitis in atopic patients--is Candida species the causative agent?

A total of 50 patients suffering both from atopic skin disease and different clinical forms of blepharitis have been included in this study. Microbiological investigations (for bacteria and fungi) of the lid margins were performed in all cases. In 21 (42%) of the patients an ulcerative blepharitis which heavily involved the follicles of the lashes was diagnosed. The remaining 29 cases presented with blepharitis of the squamous type. The cultures revealed that 19 of the 21 patients with ulcerative blepharitis were found to grow Candida species, whereas fungi could not be detected in any of the other cases of blepharitis. The frequencies of concomitant bacterial organisms found in the cultures were similar in both groups. As atopic patients are known to exhibit a defect in their cell-mediated immunity and possibly also a defective IgA antibody response it is a widely accepted assumption that these immunological changes are contributing factors to the development of a localised inflammation of the lids which is initiated by a variety of micro-organisms. We postulate that when Candida species happen to coincide with severe inflammation in atopic patients a blepharitis of the ulcerative type will develop or deteriorate thereby implying that these microorganisms may play an important role in the development or deterioration of this severe chronic inflammation. It is therefore advisable to perform repeated scrapings and cultures in every case of recalcitrant blepharitis.

Mast cell hyperplasia in atopic keratoconjunctivitis. An immunohistochemical study

Immunohistochemical staining of conjunctival biopsies from four normal subjects and five patients with atopic keratoconjunctivitis (AKC) was performed, using a monoclonal antibody to human mast cell tryptase. A massive hyperplasia of mast cells in the patients with AKC was demonstrated. The mean mast cell density in the normal patients was 55.6/mm2 and in the patients with AKC, 172/mm2. The appearance of large numbers of mast cells in the conjunctival epithelium of AKC patients was also demonstrated. The possible pathophysiological significance of these findings is discussed.

Atopic dermatitis in infants and children

Atopic dermatitis is a common, chronic inflammatory skin disease triggered by a variety of irritative emotional and allergic factors. Education and simple prevention and maintenance measures such as proper moisturizing greatly reduce disease. Antibiotics and topical corticosteroids are therapeutic mainstays.

Effects of skin contactants on evolution of atopic dermatitis in children: a case control study

There is little published literature on the effects of skin contactants during early infancy on eventual development of atopic dermatitis (AD). The purpose of this study was to determine whether or not a relationship exists between the use of skin care products in early infancy and the subsequent development of AD. We studied a group of 54 Kenyan children with AD and 63 age and sex matched controls. Emollients had been used to lubricate the skin during early infancy in a similar proportion of children in both groups (odds ratio = 0.33; 95% CI = 0.14, 0.80). Similarly, no association was found between the use of toilet soaps or laundry detergents in early infancy and development of AD. These findings suggest that baby soaps and vaseline petroleum jelly can safely be used in the skin care of AD susceptible individuals.

Atopic keratoconjunctivitis

The clinical presentation and severe complications of atopic keratoconjunctivitis, a potentially blinding disorder, were characterized in a 9-year retrospective study of 45 patients seen at a large referral center. Twenty-six patients had subepithelial fibrosis, 13 with symblepharon and/or fornix fore-shortening. Thirty-four patients had severe keratopathy, which included neovascularization in 17 patients. Persistent epithelial defect was another major complication, occurring in 21 eyes and causing severe loss of vision. These patients required interdisciplinary therapeutic strategies; systemic antihistamine therapy and strict environmental controls were the keys to success in most cases.

Post-viral fatigue syndrome, viral infections in atopic eczema, and essential fatty acids

Three clinical observations relating to viral infections are well-known but poorly understood. These are: the susceptibility of people with atopic eczema to viral infections; the occasional precipitation of an atopic syndrome by viral infections; the occurrence of a fatigue syndrome following viral infections. A unifying hypothesis is presented which explains these observations in terms of the interactions between viral infections and essential fatty acid (EFA) metabolism. Key elements of the hypothesis are the facts that interferon requires 6-desaturated EFAs in order to exert its anti-viral effects, that people with atopic eczema have low levels of 6-desaturated EFAs, and that viruses, as part of their attack strategy, may reduce the ability of cells to make 6-desaturated EFAs. The hypothesis has practical implications for the treatment of patients with viral infections.

Morphometric analyses of the skin of dogs with atopic dermatitis and correlations with cutaneous and plasma histamine and total serum IgE

In order to improve the diagnostic value of histopathologic examination of skin biopsy samples from dogs with atopic dermatitis and, perhaps, to identify any differences from the normal state that may predispose to this skin condition, we compared the anatomic and cellular morphology of skin from three standard sites in 21 normal and 15 atopic dogs. The standard sites were lateral neck, dorsal rump, and craniolateral abdomen. No differences between the two groups were found in the means of area or thickness of the stratum corneum or the remainder of the epidermis at any site. The area of sebaceous glands, but not apocrine sweat glands, was larger in the atopic group (P less than or equal to 0.05 for the lateral neck skin and P less than or equal to 0.1 for the dorsal rump skin). The mean number of non-metachromatic mononuclear cells in combined skin samples (126 microns 2) in atopic dogs (91.0 +/- 28.7) was significantly greater (P less than or equal to 0.01) than for the control normal dogs (65.3 +/- 19.3); the mean number of mast cells in atopic dogs (12.39 +/- 6.44) was similarly greater than in the controls (8.48 +/- 5.14; P less than or equal to 0.1). Eosinophils were significantly increased in atopic dog skin (P less than or equal to 0.01). with the mean for all three sites combined of 0.81 +/- 0.90 compared with a mean of 0.06 +/- 0.15 for normal dogs. Numbers of circulating blood eosinophils were not significantly different in the atopic and normal group.(ABSTRACT TRUNCATED AT 250 WORDS)

Patch testing in atopic dermatitis

Because patients with atopic dermatitis are less prone to type IV allergies, there has been controversy regarding the role of patch testing in these patients. However, recent observations indicate that patch testing with standard allergens often adds valuable information about contact sensitivity in these patients.