Is Food-Triggered Atopic Dermatitis a Form of Systemic Contact Dermatitis?

Food allergy in atopic dermatitis is mediated by complex immune interactions between genetics, diet, environment, and the microbiome. When contact between inflamed skin and food antigens occurs, contact hypersensitivity can develop. Consequently, systemic contact dermatitis (SCD) can occur after ingestion of allergenic foods or food additives in the setting of a Th2 response with CLA-positive T cells, triggering dermatitis where skin resident memory lymphocytes reside. This phenomenon explains food-triggered dermatitis. Atopy patch tests (APTs) detect sensitization to food proteins responsible for SCD, which in turn can be confirmed by oral food challenge with delayed interpretation. We summarize the literature on using APTs to identify foods for oral challenge with dermatitis as an outcome. In dermatitis patients at risk for Th2 skewing based on a history of childhood-onset flexural dermatitis, shared decision-making should include a discussion of identifying and avoiding food and food additive triggers, as well as identifying and avoiding all contact allergens, prior to initiation of systemic therapy for dermatitis.

Stasis Dermatitis: The Burden of Disease, Diagnosis, and Treatment.

Stasis dermatitis (SD), an inflammatory dermatosis occurring on the lower extremities, is a cutaneous manifestation of chronic venous insufficiency (CVI). SD is associated with a significant burden of disease. Symptoms such as pain, swelling, and itching can be debilitating for patients, leading to poor sleep, loss of mobility, and the inability to perform daily activities, and can interfere with work and leisure activities. Moreover, SD is a progressive disease with serious secondary complications such as ulcerations, which increase the patients' morbidity, reduce their quality of life, and increase health care burden. Challenges in diagnosing patients may have both short- and long-term sequalae for the patients due to unnecessary treatment and management. In addition, misdiagnosis may result in hospitalizations, placing additional burden on health care professionals in terms of time and financial burden on the health care system. Compression therapy and leg elevation represent the mainstay of treatment for CVI; however, it is also difficult to self-manage, which places a substantial burden on patients and caregivers. Moreover, compression therapy may cause discomfort and exacerbate itching. Subsequent nonadherence may result in disease progression that places additional burden on the physicians who manage these patients and the health care system in terms of resources required and costs incurred. A large proportion of patients with SD develop allergic contact dermatitis because of innate immune signals and altered skin barrier predisposing to sensitization to topical prescriptions, over-the-counter medications, and compression devices used to treat SD. Other than topical corticosteroids, there are no approved pharmacological options to treat inflammation in SD.

Stasis Dermatitis: An Overview of Its Clinical Presentation, Pathogenesis, and Management.

Stasis dermatitis is a chronic inflammatory skin disease of the lower extremities. It typically occurs in older individuals and is the cutaneous manifestation of venous hypertension caused by venous reflux. Such retrograde venous blood flow is the result of incompetent venous valves, valve destruction, or venous obstruction. Stasis dermatitis is eczematous. The associated impairment of venous valves may cause swelling of the legs, leading to serious conditions including venous ulcerations. Diagnosis can be challenging because of its clinical resemblance to other skin conditions and poor clinical recognition by physicians. The cornerstones of stasis dermatitis treatment are compression therapy to ameliorate pain and swelling, topical treatments to alleviate secondary skin changes, and interventional treatment options to correct the underlying causes of venous reflux. Given the central role of inflammation of the lower extremities in driving the cutaneous changes characteristic of stasis dermatitis, new therapeutic approaches that target the inflammation are under clinical evaluation in patients with stasis dermatitis.

Stasis dermatitis is a skin disease that can affect a person for a long time. It affects the legs of older people who have a disease called chronic venous insufficiency. This is when a person's veins have difficulty sending blood from their limbs back to their heart. Stasis dermatitis is caused by increased pressure inside a person's veins. Its signs and symptoms are skin discoloration, itch, dryness, and scaling and can be similar to the signs and symptoms of cellulitis and allergic contact dermatitis. Cellulitis is a common skin infection caused by bacteria. Cellulitis causes redness, swelling, and pain. Allergic contact dermatitis is an itchy skin rash caused by contact with something that irritates the skin. Stasis dermatitis is usually diagnosed after a healthcare provider has looked at person's skin and their medical history. Treatment for stasis dermatitis should treat the chronic venous insufficiency that causes the disease. It should also treat the skin lesions caused by stasis dermatitis. One way to treat stasis dermatitis is to reduce pain and swelling. This is done by applying pressure with compression stockings or bandages. Minor surgery can treat the venous insufficiency that causes stasis dermatitis. No treatments have been approved for the skin symptoms associated with stasis dermatitis. New ways to treat such symptoms need to be developed.

Allergic Contact Sensitization in Healthy Skin Differs from Sensitization in Chronic Dermatitis: Atopic, Occupational Wet Work, and Stasis Dermatitis.

The duration of cutaneous inflammation preceding sensitization influences the resulting allergic response; the innate immune system instructs the adaptive immune response. Potent allergens that function as their own irritant cause classic T helper cell type 1 skewed dermatitis. Examples include poison ivy, epoxy resin, and methylchloroisothiazolinone. Less potent allergens, such as food proteins and propylene glycol, sensitize skin affected by chronic dermatitis resulting in a T helper cell type 2 skewed response, sometimes with associated systemic contact dermatitis. Systemic contact dermatitis should therefore be suspected in patients with positive patch tests to ingested allergens in the setting of chronic dermatitis.

Relative Prevalence of Contact Allergens in North America in 2018.

BACKGROUND: The American Contact Dermatitis Society Contact Allergen Management Program (CAMP) database was developed to provide patients with safe alternative products free of selected contact allergens. However, the CAMP database also records valuable information including the frequency of contact allergen searches for patients. OBJECTIVES: The aim of the study was to determine the relative prevalence of contact allergens in North America. METHODS: Data from the CAMP database were analyzed from January 1, 2018, to January 1, 2019. The number of searches performed for each specific allergen served as a measure of the relative prevalence for each contact allergen. Results were then stratified by age, sex, atopic history, and patch screening tray used. RESULTS: The 2018 CAMP data show that many of the prevalent allergens are not currently on any contact allergy screening series. These data strongly indicate that testing only to an 80-item screening series will not provide adequate care for many patients with contact allergy. The most prevalent contact allergens seen were fragrance mix, nickel, balsam of Peru, methylchloroisothiazolinone/methylisothiazolinone, and cobalt. Some important differences are seen when stratifying CAMP data by age, sex, atopic history, and patch screening tray used. LIMITATIONS: Possible sources of data error exist because of lack of uniformity of patch test practices. CONCLUSIONS: The CAMP database can be used to determine the relative prevalence of contact allergens, to help develop North American core screening patch test series, and to document the medical necessity of more comprehensive patch testing for patients with recalcitrant contact allergy.

Atopy patch tests may identify patients at risk for systemic contact dermatitis.

BACKGROUND: A subset of patients with positive patch tests demonstrates systemic contact dermatitis (SCD) upon ingestion or inhalation of the allergen. Concern has been raised about the use of patch tests for protein allergens (APTs) to detect SCD in atopic dermatitis (AD) patients. METHODS: We present atopy patch test (APT) data for 97 people. We reviewed APTs and tests for antigen-specific immunoglobulin E (IgE) to the same allergen in pediatric AD patients. We compared the frequency of APTs as a function of age in AD patients. To study the irritancy potential of APTs, we prospectively tested consenting non-AD dermatitis patients undergoing evaluation for allergic contact dermatitis and healthy controls to an APT panel. RESULTS: APT demonstrated fewer positive results than serum-specific IgE or skin prick tests to the same allergen. Positive APT to food was more common in children under 3 years, whereas positive APT to aeroallergens were more common in teens and adults. Only positive APTs to dust mite were significantly more common positive in subjects without AD. CONCLUSION: Our aggregate findings suggest that most APTs, but not dust mite, behave like conventional patch tests to low-potency allergens. They are more likely to be positive in patients with chronically inflamed skin and to identify allergens that cause SCD. The higher prevalence of APT positivity to foods in young children is consistent with food allergy as a trigger of AD (also known as SCD) being more common in children than adults. Positive APTs define patients who may have SCD; negative APTs may guide elimination diets.

Atopy and Sensitization to Allergens Known to Cause Systemic Contact Dermatitis.

BACKGROUND: Atopic dermatitis (AD) associated with respiratory atopy may represent a form of systemic contact dermatitis (SCD), whereby AD flares after ingestion or inhalation of allergens. OBJECTIVE: The aim of the study was to compare the prevalence of positive patch tests to allergens known to cause SCD in AD patients with and without respiratory atopy. METHODS: This is a retrospective study of patients with AD patch tested to 23 allergens known to cause SCD. Positive patch tests were compared between AD patients with and without respiratory atopy, stratified by age and wet or dry work occupation. CONCLUSIONS: Children and adolescents, but not adults, with AD and respiratory atopy were more likely than age-matched AD patients without respiratory atopy to have positive patch tests to these allergens (odds ratio, 2.33; 95% confidence interval, 1.13-4.79). Moreover, AD patients with respiratory atopy and engaging in wet work, but not dry work, occupations were more likely than AD patients without respiratory atopy to have positive patch tests to allergens known to cause SCD (odds ratio, 1.47; 95% confidence interval, 1.05-2.06). Thus, respiratory atopy and wet work are associated with sensitization to allergens known to cause SCD in patients with AD, and patch testing may be valuable in identifying systemic triggers of dermatitis in these patients.

Patch testing for adverse drug reactions.

Adverse drug reactions result in a substantial number of hospital admissions and inpatient events. Diagnosis usually is made with clinical judgment and circumstantiality without diagnostic testing. Furthermore, even in situations where diagnostic testing is performed, no safe gold standard tests exist. Oral rechallenge is currently the gold standard but carries the risk of recrudescence of severe allergic symptoms. Other tests include skin prick tests, the lymphocyte transformation test, immunohistochemistry, and patch testing. This article provides a review of patch testing in cases of adverse drug reactions and presents new data on this topic.

A Pragmatic Approach to Patch Testing Atopic Dermatitis Patients: Clinical Recommendations Based on Expert Consensus Opinion.

Allergic contact dermatitis (ACD) may complicate the clinical course of atopic dermatitis (AD), and patch testing remains the criterion standard for diagnosing ACD. To date, there have been no guidelines or consensus recommendations on when and how to patch test individuals with AD. Failure to patch test when appropriate may result in overlooking an important and potentially curable complicating comorbidity. In this article, we present consensus recommendations regarding when to perform patch testing in the AD patient, best practices, and common pitfalls. Patch testing should be considered in AD patients with dermatitis that fails to improve with topical therapy; with atypical/changing distribution of dermatitis, or pattern suggestive of ACD; with therapy-resistant hand eczema in the working population; with adult- or adolescent-onset AD; and/or before initiating systemic immunosuppressants for the treatment of dermatitis. A suggested patch testing algorithm for AD patients is provided.

The Financial and Emotional Impact of Atopic Dermatitis on Children and Their Families.

OBJECTIVE: To examine the personal financial impact of atopic dermatitis (AD) and attempt to correlate cost of AD with emotional impact. STUDY DESIGN: Between March 2011 and December 2013, 82 caretakers of children 6 months to 12 years of age with moderate-to-severe AD were recruited at the time of dermatology clinic visits in Cleveland, Ohio, to complete surveys. The response rate was >95%. Participants were asked questions about direct expenses (medical visits, medications, and other products) and indirect expenses (time missed from work, childcare costs) related to AD in the past 4 weeks. Emotional impact was measured by the Childhood Atopic Dermatitis Impact Scale. RESULTS: The mean monthly personal cost of AD in the month before the office visit was $274 (median $114; IQR $29, $276), with $75 from direct costs (median $45; IQR $20, $110) and $199 from indirect costs (median $0; IQR $0, $208). An average of 34.8% of available monthly money was spent on AD care in the month before the office visit. For patients with Medicaid, there was a significant correlation between monthly adjusted personal cost and Childhood Atopic Dermatitis Impact Scale score (r = 0.548; P < .001); however, this correlation did not exist for patients who had commercial insurance (r = 0.269; P = .166). CONCLUSIONS: Our results illustrate the high emotional and financial burden of childhood AD and provide insight into spending patterns. In addition, our study correlate costs with emotional burden of AD for lower-income patients.

Food Avoidance Diets for Dermatitis.

Food allergy is relatively common in both children and adults, and its prevalence is increasing. Early exposure of food allergens onto skin with an impaired epidermal barrier predisposes to sensitization and prevents the development of oral tolerance. While immediate-type food allergies are well described, less is known about delayed-type food allergies manifesting as dermatitis. This is due, in part, to limitations with current diagnostic testing for delayed-type food allergy, including atopy patch testing. We conducted a systematic review of food avoidance diets in delayed-type food allergies manifesting as dermatitis. While beneficial in some clinical circumstances, avoidance diets should be used with caution in infants and children, as growth impairment and developmental delay may result. Ultimately, dermatitis is highly multifactorial and avoidance diets may not improve symptoms of delayed-type food allergy until combined with other targeted therapies, including restoring balance in the skin microbiome and re-establishing proper skin barrier function.

Polysensitization and individual susceptibility to allergic contact dermatitis.

BACKGROUND: Patients with allergic contact dermatitis to 1 antigen have been shown to be at increased risk of developing delayed type hypersensitivity reactions to additional antigens. Both environmental and genetic factors likely influence the risk of sensitization. OBJECTIVE: The aim of this study was to determine whether polysensitization occurs at a higher frequency than would be expected based on chance and whether polysensitization occurs more often in subsets of patients with hand involvement and atopic dermatitis. METHODS: From a database of patch test results from a single practitioner, the probability of having positive reactions to 3 or more unrelated allergens was calculated under the assumption that positive reactions are independent and compared with the observed proportion having positive reactions to 3 or more unrelated allergens. The analysis was repeated excluding patients with leg involvement as a proxy for venous insufficiency dermatitis. The proportion of patients from the polysensitized and nonpolysensitized cohorts with either hand involvement or a history of atopic dermatitis was also calculated. CONCLUSIONS: Polysensitization occurs more often than expected based on chance. Polysensitized patients were more likely to have hand dermatitis. Atopic dermatitis was not significantly associated with polysensitization in this analysis. Polysensitized individuals may represent a phenotype with increased genetic susceptibility to sensitization.

A systematic review of topical corticosteroid withdrawal ("steroid addiction") in patients with atopic dermatitis and other dermatoses.

BACKGROUND: The National Eczema Association has received increasing numbers of patient inquiries regarding "steroid addiction syndrome," coinciding with the growing presence of social media dedicated to this topic. Although many of the side effects of topical corticosteroids (TCS) are addressed in guidelines, TCS addiction is not. OBJECTIVE: We sought to assess the current evidence regarding addiction/withdrawal. METHODS: We performed a systematic review of the current literature. RESULTS: Our initial search yielded 294 results with 34 studies meeting inclusion criteria. TCS withdrawal was reported mostly on the face and genital area (99.3%) of women (81.0%) primarily in the setting of long-term inappropriate use of potent TCS. Burning and stinging were the most frequently reported symptoms (65.5%) with erythema being the most common sign (92.3%). TCS withdrawal syndrome can be divided into papulopustular and erythematoedematous subtypes, with the latter presenting with more burning and edema. LIMITATIONS: Low quality of evidence, variability in the extent of data, and the lack of studies with rigorous steroid addiction methodology are limitations. CONCLUSIONS: TCS withdrawal is likely a distinct clinical adverse effect of TCS misuse. Patients and providers should be aware of its clinical presentation and risk factors.

Sensitization prevalence for benzalkonium chloride and benzethonium chloride.

BACKGROUND: Benzalkonium chloride (BAK) and benzethonium chloride (BEC) are well-characterized skin irritants and rare sensitizers, but optimal testing for allergic contact dermatitis (ACD) is not established. OBJECTIVE: Sensitization prevalence was sought, and several patch testing concentrations and vehicles were compared. METHODS: One hundred forty-two patients tested to the standard screening series for evaluation of dermatitis consented to additional tests including BAK 0.15% aqueous (aq), BAK 0.15% petrolatum (pet), BEC 0.15% aq, and BEC 0.5% aq. Follow-up to assess clinical relevancy included early and late patch test reads, 1-month clinical follow-up, and long-term phone calls. Patients were categorized as definite, possible, or unlikely to have ACD to BAK and/or BEC. RESULTS: Atopy was not associated with patch test reactions (P = 0.154). Seventy-five percent (6/8) of the patients with possible ACD to BAK had coreactions with BEC. Testing to both BAK 0.15% pet and 0.15% aq would have identified 91% of those with possible ACD to BAK, twice as many than if only BAK 0.1% aq from the standard series was used. CONCLUSION: Sensitization to BAK and BEC, although rare, does occur. Weak and morphologically irritant reactions at day 7 reading can be relevant. We recommend testing to BAK 0.15% aq and 0.15% pet to increase sensitivity and having patients undergo long-term follow-up.

Effects of occlusion on the skin of atopic dermatitis patients.

BACKGROUND: Atopic dermatitis (AD) may be exacerbated by occlusion from items such as occlusive gloves or textiles, especially if the occlusion is removed suddenly, creating a steep humidity gradient. Most previous studies of occlusion have focused on normal skin. Occlusion has been shown to be beneficial in psoriatic skin, but many atopic patients complain of increased inflammation after occlusion. OBJECTIVE: To evaluate the response of noninflamed AD skin to occlusion. METHODS: Six patients with AD were patch-tested with occlusive polyethylene wrap and sodium lauryl sulfate (SLS) in standard Finn Chambers taped to noninflamed skin of the back. Cytokine and chemokine messenger ribonucleic acid (mRNA) for interleukin-8 (IL-8), interleukin-1 alpha (IL-1α), and interleukin-1 receptor antagonist (IL-1RA), as well as the 18S rRNA housekeeping gene, was obtained via tape-stripping the skin and measured using quantitative real-time polymerase chain reaction. We also measured transepidermal water loss after removal of occlusion. RESULTS: Polyethylene occlusion alone with abrupt removal induced IL-8 and IL-1α levels similar to or exceeding that of SLS. IL-1RA was up-regulated by SLS and occlusion, with SLS showing a stronger response. CONCLUSION: Removal of occlusion with polyethylene film up-regulates the inflammatory cytokines IL-8, IL-1α, and IL-1RA in patients with AD. This may explain the worsening of AD with the use of occlusive gloves, athletic equipment, and fabrics.

"Dermatitis" defined.

BACKGROUND: The term "dermatitis" can be defined narrowly or broadly, clinically or histologically. A common and costly condition, dermatitis is underresourced compared to other chronic skin conditions. The lack of a collectively understood definition of dermatitis and its subcategories could be the primary barrier. OBJECTIVE: To investigate how dermatologists define the term "dermatitis" and determine if a consensus on the definition of this term and other related terms exists. METHODS: A seven-question survey of dermatologists nationwide was conducted. RESULTS: Of respondents (n  =  122), half consider dermatitis to be any inflammation of the skin. Nearly half (47.5%) use the term interchangeably with "eczema." Virtually all (> 96%) endorse the subcategory "atopic" under the terms "dermatitis" and "eczema," but the subcategories "contact," "drug hypersensitivity," and "occupational" are more highly endorsed under the term "dermatitis" than under the term "eczema." Over half (55.7%) personally consider "dermatitis" to have a broad meaning, and even more (62.3%) believe that dermatologists as a whole define the term broadly. CONCLUSION: There is a lack of consensus among experts in defining dermatitis, eczema, and their related subcategories.