Patch-test reaction patterns in patients with a predisposition to atopic dermatitis

Patch Testing With Cobalt in Adults: A North American Contact Dermatitis Group Experience, 2001-2018

Background: Cobalt is a recognized cause of allergic contact dermatitis (ACD); however, detailed information on patient characteristics, sites, and sources is lacking. Objective: The aim of the study is to assess trends in patch test reactions to cobalt and associated patient characteristics, common sources, and body sites affected. Methods: The study used a retrospective analysis of adult patients who were patch tested to cobalt by the North American Contact Dermatitis Group between 2001 and 2018 (n = 41,730). Results: Overall, 2986 (7.2%) and 1362 (3.3%) had allergic or currently relevant patch test reaction to cobalt, respectively. Patients with versus without an allergic patch test reaction to cobalt were more likely to be female, employed, have a history of eczema or asthma, be Black, Hispanic, or Asian, and have occupational-related dermatitis. The most commonly identified sources of cobalt in allergic patients included jewelry, belts, and cement, concrete, and mortar. Affected body site(s) varied by cobalt source among patients with currently relevant reactions. Occupational relevance was found in 16.9% of patients with positive reactions. Conclusions: Positive patch test reactions to cobalt were common. The most common body sites were the hands, and affected site varied by the source of cobalt.

Atopic skin diathesis rather than atopic dermatitis is associated with specific contact allergies

BACKGROUND

The association of atopic dermatitis (AD) and allergic contact dermatitis has been a matter of considerable uncertainty. Study results range from lack of any association to increased sensitization for multiple allergens, but fail to identify consistent allergen associations.

OBJECTIVE

We studied a large patch test cohort of patients stratified by their atopic skin diathesis using the Erlangen Atopy Score (EAS), independent of active skin disease.

METHODS

Retrospective multi-center data analysis from five departments of dermatology in Germany with 4,509 patients. Patients were grouped as "no atopic skin diathesis" (n = 2,165) and "atopic skin diathesis" (n = 1,743), according to EAS.

RESULTS

Significantly more individuals with atopic skin diathesis showed at least one positive patch test reaction to the baseline series compared to individuals without atopic skin diathesis (49.1 % vs. 38.3 %). In logistic regression analyses, atopic skin diathesis was associated with a significantly higher risk of sensitization to methylchloroisothiazolinone/methylisothiazolinone (OR 2.383) and methylisothiazolinone (OR 1.891), thiuram mix (OR 1.614), as well as nickel (OR 1.530), cobalt (OR 1.683), and chromium (OR 2.089).

CONCLUSIONS

Atopic skin diathesis proved to be the most important intrinsic risk factor for contact sensitization to few, specific allergens. Past or present AD was a less relevant variable.

Atopy patch testing with aeroallergens in a large clinical population of dermatitis patients in Germany and Switzerland, 2000-2015: a retrospective multicentre study

BACKGROUND

The diagnostic significance of the atopy patch test for the management of dermatitis possibly triggered by aeroallergens is still controversial. However, sufficiently large studies with routinely tested standardized aeroallergen patch test preparations in dermatitis patients are lacking.

OBJECTIVE

To evaluate the reaction frequency and the reaction profiles of 10 until mid-2015 commercially available, standardized aeroallergen patch test preparations of the 'Stallerpatch' test series (Stallergenes, Antony Cedex, France) in a large multicentre patient cohort.

METHODS

A retrospective data analysis of patients with suspected aeroallergen-dependent eczematous skin lesions was performed, who were patch tested in 15 Information Network of Departments of Dermatology-associated clinics between 2000 and 2015. Patients were stratified according to their atopic dermatitis (AD) status.

RESULTS

The study group included 3676 patients (median age 41 years, 34.8% males, 54.5% AD). The most common aeroallergens causing positive patch test reactions were Dermatophagoides pteronyssinus (19.6%), Dermatophagoides farinae (16.9%), birch (6.2%), timothy grass (6.0%), cat dander (5.4%), mugwort (4.9%) and dog dander (4.6%). Reactions to other pollen allergen preparations, that is 5 grasses (3.2%), cocksfoot (2.1%) and plantain (1.6%), were less common. Positive patch test reactions to aeroallergens were consistently more frequent in patients with AD. These patients showed proportionally less dubious, follicular, irritant and weak positive reactions. Independent of AD status, a patient history of past or present allergic rhinitis was associated with an increased chance of a positive aeroallergen patch test reaction to pollen allergens.

CONCLUSION

The aeroallergen patch test is a useful add-on tool in clinical routine, especially in patients with AD and/or respiratory allergy. A patch test series comprising Dermatophagoides pteronyssinus, Dermatophagoides farinae, birch, timothy grass, cat dander and mugwort seems to be suitable. Controlled studies with specific provocation and elimination procedures are required to further evaluate the diagnostic significance of the proposed screening series.

The Role and Diagnosis of Allergic Contact Dermatitis in Patients with Atopic Dermatitis

Patients with atopic dermatitis (AD) have increased penetration of allergens, immune dysregulation (including shared cytokine pathways), and frequent use of emollients and topical medications, all of which may predispose toward developing allergic contact dermatitis (ACD). Recent systematic reviews have suggested that ACD is a significant clinical problem in both children and adults with AD. While this remains controversial, ACD remains an important comorbidity and potential exacerbant of AD in clinical practice. Common relevant allergens, include lanolin, neomycin, formaldehyde, sesquiterpene lactone mix, compositae mix, and fragrances that are commonly found in AD patients' personal care products. We herein review the clinical scenarios where patch testing is indicated in AD. In addition, we review the contraindications, preferred patch-testing series, pitfalls, and challenges determining the relevance of positive patch-test reactions in AD patients.

The multiple factors affecting the association between atopic dermatitis and contact sensitization

Atopic dermatitis and allergic contact dermatitis are both common skin diseases having an immune pathogenesis. There has been considerable interest about their inter-relationships with regard to altered susceptibility. Recent investigations have shed new light on this important question, and in this article, we explore whether there is evidence that atopic dermatitis affects the risk of contact sensitization and allergic contact dermatitis. The use of topical products to treat xerotic and inflamed skin in atopic dermatitis often results in a higher prevalence of sensitization to, for example, fragrances and other ingredients in emollients. Moreover, the prevalence of metal allergy seems to be increased, probably due to compromised chelation of the metals in the stratum corneum of patients with atopic dermatitis. However, conversely, the T-helper cell 2 bias that characterizes immune responses in atopic dermatitis appears to lower the risk of contact sensitization compared to healthy controls. Based on these observations, we conclude that multiple factors affect the association between atopic dermatitis and contact sensitization, and that these need to be appreciated in the clinical management of atopic dermatitis patients.

Abnormal epidermal barrier in the pathogenesis of contact dermatitis

A crucial role of the epidermal permeability barrier is obvious in contact dermatitis. An intact skin barrier prevents the penetration of harmful substances into the skin. Irritants and allergens that stay on the skin surface and come into contact with the stratum corneum only do not harm the skin. After disruption of the skin barrier, however, irritants may penetrate into the living epidermal layers, injure the keratinocyte membrane, and release cytokines, which leads to inflammation and to irritant contact dermatitis. The skin barrier is often disrupted by chronic exposure to water plus detergents, solvents, or other irritants. A disrupted barrier in irritant contact dermatitis also allows for the penetration of allergens. Allergens may come into contact with Langerhans and T cells, induce immunological reactions, and cause inflammation, which results in allergic contact dermatitis. Treatments in contact dermatitis should restore the skin barrier to prevent relapse of the disease. Topical corticosteroids, most often used in treating contact dermatitis, reduce immunological reactions and inflammation but do not lead to a complete barrier repair. Skin barrier repair is more complete after treatment with calcineurin inhibitors and bland lipid-based emollient; therefore, these preparations should be preferred for long-term treatment of contact dermatitis.

Contact sensitivity to metals (chromium, cobalt and nickel) in childhood

Metals, especially nickel, are the most common contact allergens in children. Recent data has shown increased incidence of allergy in industrialized countries. Sensitization can occur at any age, even in neonates. Costume jewelry, particularly earrings, is linked to increased sensitization to nickel. Sensitization to cobalt often occurs by the use of costume jewelry. The most common source of sensitization to chromium is leather. Due to the absence of a specific therapy, the main treatment is to identify and avoid the responsible allergens. This article presents an updated view on the epidemiological and clinical aspects of contact allergy to metals, focusing on prevention strategies and risk factors, and warns about possible and new sources of contact.

Characteristics of patch test reactions to common preservatives incorporated in petrolatum and water, respectively

BACKGROUND

The irritant properties of some preservatives and the use of water as the patch test vehicle for some of them call for a critical evaluation of patch test reactions to preservatives.

OBJECTIVES

To examine the association between test vehicle (petrolatum versus water) or the patients' age and history of atopic dermatitis, respectively, and certain patterns of reaction to preservatives.

PATIENTS/METHODS

Data of 34,631 patients tested in 34 centres with 11 common preservatives were retrospectively analysed. The dynamic reaction patterns, reaction indices (RIs) and positivity ratios (PRs) were statistically evaluated.

RESULTS

All preservatives yielded more crescendo reactions in older than in younger patients. For 10 of 11 preservatives, the percentage of crescendo reactions was slightly higher in patients without a history of atopic dermatitis, and for 10 of 11 agents the RI was higher in patients with a positive history of atopic dermatitis. No consistent vehicle-related effects on reaction characteristics were found. Chlorhexidine digluconate 0.5% in water and sodium benzoate 5% in petrolatum had the lowest RIs, highest PRs, and lowest proportions of crescendo reactions.

CONCLUSIONS

Water as a vehicle is unlikely to affect the reaction patterns of preservatives. The generally used patch test preparations of chlorhexidine digluconate and sodium benzoate need improvement.

Validity of self-reported nickel allergy

BACKGROUND

To estimate the prevalence of nickel allergy, self-reports are sometimes used in epidemiological studies. Self-reports are practical and may facilitate estimation of prevalence provided that the questions are validated.

OBJECTIVES

To investigate the validity of self-reported nickel allergy.

METHODS

Three hundred and sixty-nine women, aged 30-40 years, from the general population participated in the study. The participants answered a questionnaire before a clinical examination and patch testing. The two questions being validated were 'Are you sensitive/hypersensitive/allergic to nickel?' and 'Do you get a rash from metal buttons, jewellery or other metal items that come in direct contact with your skin?'

RESULTS

Patch test showed nickel-positive reaction in 30% of the subjects. Self-reported prevalence of nickel allergy as indicated by the two respective questions was 40% and 35%. Positive predictive values for the two questions were 59% (95% CI 50-67) and 60% (95% CI 51-69). History of childhood eczema was over-represented among women with 'false-positive' self-reported nickel allergy (P = 0.008). Self-reported hand eczema or 'high wet exposure' did not influence the validity.

CONCLUSIONS

The validity of self-reported nickel allergy is low. The questions regarding nickel allergy overestimate the true prevalence of nickel allergy.

Characterization of the polysensitized patient: a matched case-control study

BACKGROUND

Polysensitization ( >or= 3 contact allergies) may be regarded as a special entity in patients with contact allergies. However, this group of polysensitized patients is poorly characterized. Filaggrin mutations are associated with atopic eczema and lead to impaired skin barrier which may predispose to contact allergy. Therefore, it is of interest to consider atopic eczema and contact allergies, especially in patients with multiple allergies.

OBJECTIVE

To characterize polysensitized patients regarding occurrence, duration and course of dermatitis, and examine potential risk factors for polysensitization, including atopic eczema.

METHODS

A questionnaire case-control study of 562 polysensitized and 1124 single/double-sensitized individuals was performed.

RESULTS

The results show that 45% of polysensitized and 31% of single/double-sensitized patients had or had had atopic eczema, and atopic eczema was identified as a risk factor for polysensitization. Patients with leg ulcer constituted only a minor part of the polysensitized group and leg ulcers were not identified as a risk factor for polysensitization in this study. The influence of contact allergies on duration and course of disease diverged between the group of patients with atopic eczema and the group without atopic eczema.

CONCLUSION

Patients with atopic eczema were overrepresented in the group of polysensitized patients and polysensitized patients should be viewed in the light of occurrence or lack of atopic eczema.

Individual susceptibility to occupational contact dermatitis

Occupational Contact Dermatitis (OCD) is one of the most common work-related diseases. High risk occupations are in health care, hairdressing, food sector and metal industry. OCD tends to become chronic; persistent OCD often results in impaired quality of life and loss of work ability. The purpose of this article is to review the present knowledge on the factors which determine individual susceptibility to acquire OCD. Recent discoveries regarding genes involved in the skin barrier, inflammatory response and biotransformation of xenobiotics provide more insight in the individual susceptibility for OCD. Knowledge of the factors which predispose to OCD is useful in occupational health practice for the application of preventive measures and for career guidance for apprentices and workers in high risk occupations.

Atopy and contact allergy to fragrance: allergic reactions to the fragrance mix I (the Larsen mix)

BACKGROUND

The relationship between an atopic diathesis and contact sensitization to fragrances is unclear.

OBJECTIVE

To investigate whether there is an association between atopy and allergy to fragrance mix I (FM I).

PATIENTS/METHODS

The computerized files of patients patch tested to FM I at St John's Institute of Dermatology (1980-2004) were reviewed. Demographic details recorded for all patch-tested patients included age, sex, date of testing, history of current or previous atopic eczema (AE), history of current or previous asthma nor hay fever (A/HF), family history (FH) of any type of atopy, and any positive patch tests.

RESULTS

About 8.4% of females (1713/20 338) and 6.6% of males (903/13 734) were allergic to FM I. About 8.95% (101/1129) of females with AE were allergic to FM I versus 8.63% (619/7171) of females who had neither AE and A/HF nor FH (non-atopics) (P = 0.72). About 5.6% (40/710) of males with AE were positive to FM I versus 6.9% (427/6201) of male non-atopics (P = 0.23). There was a striking increase in AE and A/HF during this 25-year period (P < 0.0001).

CONCLUSIONS

We found no association between atopy and allergy to FM I. There has been a marked increase in atopy in individuals referred for patch testing in the past 25 years.

Nickel allergy--prevalence in a population of Swedish youths from patch test and questionnaire data

BACKGROUND

The prevalence of body piercing and orthodontic treatment has increased during recent decades. Such changes in lifestyle may influence the occurrence of nickel allergy.

OBJECTIVES

The aim of this study was to describe the prevalence of nickel allergy in a Swedish youth population.

METHODS

In a cross-sectional survey, 6095 adolescents answered a questionnaire on their lifestyle and medical history, and 4439 consented to patch testing for contact allergy. Patch test results were adjusted for dropouts by a missing value analysis.

RESULTS

The prevalence of self-reported dermatitis from contact with metal items was 14.8%. Patch testing showed nickel sensitization in 9.9% of the subjects, and in significantly more girls than boys, 13.3% versus 2.5%, respectively. Taking the dropout into account, the estimated true prevalence of nickel sensitivity evaluated by test reading at D4 is 11.8% in girls and 1.6% in boys.

CONCLUSIONS

The prevalence of nickel sensitization was higher for girls and slightly lower for boys compared with previous Swedish data. Self-reported information on metal dermatitis as an estimate of nickel allergy has low validity. When possible, missing value analysis should be performed to account for dropouts.

Macro-video documentation patch tests

An unequivocal distinction between allergic and irritant patch test reactions is often difficult with patch tests. This study was designed to evaluate the worth of video-macro camera documentation for differentiation between allergic and irritant test reactions and to investigate whether there are characteristic clinical differences in patch test responses between metal salts and fragrances. Patch testing was performed with nickel sulfate, fragrance mix and an irritant, sodium lauryl sulfate 1% aq., on the upper back of 82 patients, with evaluation and computer-aided video documentation after 48 and 72 hr. No reliable clinicomorphological criterion was found for assessing a weak patch test reaction as being definitely allergic. Even characteristic papules and vesicles were not regularly found in allergic reactions. However, unlike fragrance mix, patch test reactions to nickel sulfate were characteristic in that they showed a heterogeneous spread and an association with hair follicle openings, independent of reaction intensity. Evaluation based on additional computer-aided video-macro camera documentation did not add further advantage for the differentiation of allergic and irritant reactions. But well-defined clinicomorphological features and reaction patterns to single test substances or even whole substance categories could be helpful additional criteria for evaluating patch test responses in clinical practice.

Iodopropynylbutyl carbamate 0.2% is suggested for patch testing of patients with eczema possibly related to preservatives

BACKGROUND

Iodopropynyl butylcarbamate (IPBC) is a new preservative in medical and cosmetic leave-on products. Although cases of allergic contact dermatitis to IPBC have been reported, it is not known whether the usual test concentration of 0.1% is appropriate for screening tests with IPBC.

OBJECTIVES

To determine the concentration of IPBC that should be used in screening patch tests.

METHODS

An analysis was made of data filed by 26 centres of dermatology on patch tests performed with one or two concentrations of IPBC (0.1%, 0.2%, 0.3% or 0.5%) in 8106 unselected patients. Criteria used to determine the best test concentration of IPBC were the reaction index, the positivity ratio, the rate of crescendo reactions, and the relations between IPBC reactions and the MOAHLFA index irritant reactions to sodium lauryl sulphate (SLS), and allergic reactions to other contact allergens including preservatives.

RESULTS

IPBC 0.1%, 0.2%, 0.3% and 0.5% yielded 0.5%, 0.8%, 1.3% and 1.7% positive reactions, but this increase was accompanied by an even greater increase in doubtful and irritant reactions. These figures and the other criteria examined suggested the range of suitable test concentrations of IPBC to lie between 0.2% and 0.3%. A detailed analysis of MOAHLFA indices and of associations between reactions to IPBC and reactions to other allergens and to SLS showed that most of the positive reactions to IPBC 0.2% can be assumed to be allergic ones and that with IPBC 0.2% fewer false-positive reactions can be expected than with IPBC 0.3%.

CONCLUSIONS

Patch testing with IPBC 0.2% is suggested for patients with eczema possibly related to preservatives.