Contact dermatitis

Peripheral inflammation as a potential mechanism and preventive strategy for perioperative neurocognitive disorder under general anesthesia and surgery

General anesthesia, as a commonly used medical intervention, has been widely applied during surgical procedures to ensure rapid loss of consciousness and pain relief for patients. However, recent research suggests that general anesthesia may be associated with the occurrence of perioperative neurocognitive disorder (PND). PND is characterized by a decline in cognitive function after surgery, including impairments in attention, memory, learning, and executive functions. With the increasing trend of population aging, the burden of PND on patients and society's health and economy is becoming more evident. Currently, the clinical consensus tends to believe that peripheral inflammation is involved in the pathogenesis of PND, providing strong support for further investigating the mechanisms and prevention of PND.

Triggered Skin Sensitivity: Understanding Contact Dermatitis

Dermatitis, the incendiary reaction of the skin to various components, can manifest in various types, including atopic dermatitis, contact dermatitis, nummular eczema, seborrhoea, and stasis dermatitis. Atopic dermatitis is the most common skin disease in children and has a growing prevalence in recent years. It is characterized by extreme tingling, eczemous skin injuries, dryness of the skin, and a family history of atopic illnesses. Contact dermatitis (CD) is a common, irritating skin disorder caused by allergens and aggravating elements in the environment. It is the most common cause of work-related dermatitis and plays a substantial role in hand and face dermatitis. A complete restorative history is essential for establishing CD and identifying the allergies that cause it. Fix testing, skin tests for fast contact reactions, serum allergen-specific IgE testing, subjective and quantitative evaluation of allergens inside probable items patients were exposed to, and challenge testing are among the other diagnostic techniques. To avoid a breakdown and the continuation of the skin illness, early and suitable therapy is critical. Allergic dermatitis to contact (ACD) develops during the normal, delayed incendiary reaction and has a perplexing etiology. Accurate identification of the allergen that is causing the reaction allows for adequate individual avoidance. The major treatment alternatives continue to be corticosteroids. Nickel-contact dermatitis is an allergic reaction that affects both children and adults. Adverse contact dermatitis (ACD) is a frequent skin reaction to a common allergen that can affect both children and adults. Less than 10% of all diagnostic procedures in pediatric patients involve checking for ACD symptoms. To answer the clinical question, a thorough history is gathered based on appearance, age group, and dermatitis type. According to pediatricians in the US, metals, perfumes, topical antimicrobials, excessive chemicals, and fabric softeners are the most typical allergens.

A review of skin disease in military soldiers: challenges and potential solutions

Introduction: Military soldiers comprised 1,195 million United States active-duty members and 778,000 reserve members in 9/2021. Soldiers are often exposed to drastic climates, environments, and living conditions which may make them more susceptible to cutaneous diseases.Methods: A PubMed search of studies published between 1/1/2002 - 8/30/2022, using MeSH terms: ((("Military Personnel"[Majr]) OR "Military Hygiene"[Majr])) OR "Military Medicine"[Majr]) AND "Skin Diseases"[Majr]), the reference lists of select articles, and other applicable sources were reviewed to identify articles on skin conditions affecting military soldiers and treatment options.Discussion: In this article, we review skin conditions that affect military soldiers in both the deployed and non-deployed settings including infectious diseases, arthropod associated diseases, sexually transmitted infections, ultraviolet radiation related skin disease, acne, diseases of hair and hair follicles, dermatitis, onychocryptosis, and conditions caused by extreme weather conditions and occupational exposures. We also discuss treatment options and prevention methods as they relate to military settings.Conclusion: Dermatological conditions can considerably impact soldiers' wellbeing and military performance, often lead to evacuation of military personnel, and are associated with high financial costs. Cutaneous disease is one of most common reasons for soldiers to seek medical care and may cause significant morbidity. Serving in the military often impacts and limits treatment options.

Seven Common Allergen Groups Causing Eyelid Dermatitis: Education and Avoidance Strategies

Objective

Eyelid dermatitis is most commonly attributed to allergic response. This retrospective clinical study identifies common allergens with eyelid involvement and addresses a literary gap by providing a clear approach for effective management of periorbital allergic contact dermatitis (ACD) recurrence.

Methods

Charts of 215 patients diagnosed with periorbital dermatitis who were patch tested with Mayo Clinic Standard Series, Extended Standard Series, and personal products from 2013 to 2017 were examined. Positive reaction rates for patients with eyelid involvement were compared to those without. Findings were also compared to North American Contact Dermatitis Group (NACDG) 2013–2014 and Mayo Clinic Contact Dermatitis Group (MCCDG) 2011–2015 general patch test populations.

Results

The 215 patients showed more common allergy to shellac, benzalkonium chloride, acrylates, and surfactants than the NACDG and MCCDG study populations. Periorbital ACD allergen groups eliciting the highest positive reaction rates were, in descending order: metals, shellac, preservatives, topical antibiotics, fragrances, acrylates, and surfactants. Of the corticosteroids, only tixocortol pivalate (the screening agent for prednisolone and fluorometholone) and budesonide elicited positive reactions.

Conclusion

The top seven eyelid ACD allergen groups were identified. Avoidance of these allergens can be straightforward, with initial empiric counseling and free, online allergen avoidance programs. Patients who are unresponsive to avoidance should undergo patch testing.

Experience in patch testing: A 6-year retrospective review from a single academic allergy practice

BACKGROUND

Patch testing is the "gold standard" to identify culprit allergen(s) causing allergic contact dermatitis (ACD), but there are limited studies of patch testing from allergy practice settings.

OBJECTIVE

We sought to explore patch test findings in a large academic allergy practice, including patch testing results, history of atopy, location of dermatitis, and referral source. We also wanted to determine whether patch testing using an extended panel, such as the North American screening series, compared with a limited series, such as the Thin-Layer Rapid-Use Epicutaneous (T.R.U.E.) Test, increased the sensitivity.

METHODS

A retrospective chart review was conducted of patients referred for patch testing over a 6-year period.

RESULTS

A total of 585 patients (mean age 48.7 years, 71.6 % female) underwent patch testing over the 6-year period, of which 369 (63%) had a positive test. Of those who tested positive, 202 (55%) reported a history of atopy. The extremities were the most commonly involved site, followed by the head/neck and trunk. The 5 most common positive allergens were nickel sulfate, gold sodium thiosulfate, methylchloroisothiazolinone, thimerosal, and bacitracin. Three hundred fourteen (53.6%) patients were positive to at least 1 allergen on TRUE testing. Extended screening series identified an additional 10.8% of patients with positive tests who were negative to T.R.U.E. test allergens.

CONCLUSION

Patch testing is a valuable diagnostic tool for the practicing allergist and provides early identification of culprit allergens in ACD. Performing an extended screening series such as the North American Contact Dermatitis Group (NACDG) or supplemental panel of allergens increased sensitivity when compared with a limited series.

Contact dermatitis: in pursuit of sensitizer's molecular targets through proteomics

Protein haptenation, i.e., the modification of proteins by small reactive chemicals, is the key step in the sensitization phase of allergic contact dermatitis (ACD). Despite the research effort in past decades, the identification of immunogenic hapten-protein complexes that trigger a relevant pathogenic immune response in ACD, as well as the haptenation reaction molecular site, and the elements of a potentially conditioning environment during each of these stages, remain poorly understood. These questions led us to employ a proteomics-based approach to identify modified proteins in the dendritic-like cell line THP-1 sensitized with fluorescein isothiocyanate (FITC), through a combination of 2D-gel electrophoresis, nano-LC and mass spectrometry. A specific set of 39 targeted proteins was identified and comprised proteins from various cellular locations and biological functions. One of FITC targets was identified as MLK, a member of the mixed-lineage kinase family known to act as a mitogen-activated protein kinase kinase kinase and to control the activity of specific mitogen-activated protein kinase pathways, namely p38 and JNK pathways. Haptenated in the vicinity of its active site, our results point to MLK being a relevant target due to a consistent non-activation at early time points of these pathways upon FITC sensitization in THP-1 cells. Moreover, FITC pre-treatment significantly decrease phospho-p38 and phospho-JNK levels induced upon exposure to a classical activator such as lipopolysaccharide or to the sensitizer 2,4-dinitrofluorobenzene. Overall, our data point to specific amino acid residues haptenation within critical proteins as the key step in the subsequent signaling pathways modulation responsible for DC activation and maturation events.

Transdermal rivastigmine: management of cutaneous adverse events and review of the literature

Alzheimer's disease is a chronic neurodegenerative disorder resulting in part from the degeneration of cholinergic neurons in the brain. Rivastigmine, a cholinesterase inhibitor, is commonly used as a treatment for dementia due to its ability to moderate cholinergic neurotransmission; however, treatment with oral rivastigmine can lead to gastrointestinal adverse effects such as nausea and vomiting. Transdermal administration of rivastigmine can minimize these adverse effects by providing continuous delivery of the medication, while maintaining the effectiveness of the oral treatment. While the transdermal form of rivastigmine has been found to have fewer systemic adverse effects compared with the oral form, cutaneous reactions, such as contact dermatitis, can lead to discontinuation of the drug in its transdermal form. Lack of patient compliance with regard to applying the patch to the designated site, applying the patch for the correct length of time or rotating patch application sites increases the risk of cutaneous adverse reactions. This article outlines the diagnosis and management of irritant contact dermatitis and allergic contact dermatitis secondary to transdermal rivastigmine. The large majority of reactions to transdermal patches are of an irritant type, which can be diagnosed clinically by the presence of a pruritic, erythematous, eczematous plaque strictly confined to the borders of the patch. In contrast, an allergic reaction can be differentiated by the presence of vesicles and/or oedema, erythema beyond the boundaries of the transdermal patch and lack of improvement of the lesion 48 hours after removal of the offending treatment. By encouraging the patient to follow a regular rotation schedule for the patch, and using lipid-based emollients for irritant dermatitis and pre- and post-treatment topical corticosteroids for allergic dermatitis, cutaneous reactions can often be alleviated and patients can continue with their medication regimen. Other simple changes to a patient's treatment routine, including minimizing the use of harsh soaps, avoiding recently shaven or damaged areas of skin and carefully removing the patch after use, can help to further decrease the risk of dermatitis development.

Allergy skin testing: what nurses need to know

Skin testing is a common procedure in any clinical setting. Critical care nurses will encounter skin testing in the inpatient and outpatient settings primarily to test for patient allergies to environmental factors, or allergies to certain medications. As there is a great deal of controversy about standard practices surrounding the different tests, information about various allergy tests and testing protocols is vital. Quality assurance standards should be met to ensure adequacy of the skin testing technique. Persons performing skin tests should undergo evaluation of their technique. To improve the predictive values of skin testing, and to ameliorate the incidence or severity of adverse affects, it is important for the critical care nurse to understand the dynamics of the test and the possible risks, along with variables that can confound the results. By doing this, nurses will improve not only patient outcomes related to the testing itself but also the value and reliability of the most effective diagnostic tool available for allergic disease.

Allergic skin disease: major highlights and recent advances

AD, urticaria, and ACD account for a large percentage of the skin disorders that present at medical offices and emergency departments. With a high degree of morbidity, these diseases can be extremely difficult to manage. Consequently, these diseases continue to be the focus of much of the new research in the field. Recent studies have furthered the understanding of the complex relationship between immune and nonimmune factors in the pathogenesis of these disorders. This research has quickly led to the development of new treatment modalities and protocols for patient care, especially for AD. However, further discovery will be necessary to optimize the management of these often-vexing conditions.

Practical management of cutaneous reactions to the methylphenidate transdermal system: recommendations from a dermatology expert panel consensus meeting

BACKGROUND

Psychostimulants remain the most-used medications for attention-deficit/hyperactivity disorder (ADHD). The methylphenidate transdermal system (MTS) is the first stimulant patch dosage formulation to be approved by the US Food and Drug Administration for the treatment of the symptoms of ADHD in children aged 6 to 12 years. The MTS patch is approved to be applied once daily to the hip and worn for 9 hours. While cutaneous reactions may occur with any formulation of medication, they are more likely with transdermal administration.

OBJECTIVE

The purpose of this commentary was to describe the types of cutaneous reactions that have been reported with transdermal systems in general, review the cutaneous adverse events seen in clinical trials with the MTS specifically, and provide practical management suggestions for prevention and treatment of these potential cutaneous reactions.

METHODS

In September 2007, a group of child psychiatrists, pediatricians, developmental pediatricians, and pediatric neurologists who treat ADHD and have had experience in their practices with MTS convened to discuss cutaneous reactions in relation to its use. Information collected from this meeting and from the clinical trials database of the sponsor was reviewed by a panel of 3 dermatologic clinical experts in contact dermatitis and 1 pediatric dermatologist. The panel's recommendations form the basis for this report.

CONCLUSIONS

Mild to moderate erythema is a common cutaneous effect with MTS use, and is generally not a cause for discontinuation if seen in isolation. Irritant contact dermatitis is relatively common and can be reduced and treated by alternating patch application sites, moisturizing, gentle skin care, and application of topical corticosteroids at the previous patch sites if needed. Allergic contact dermatitis (ACD) and allergic contact urticaria are rare when MTS is worn as directed in the prescribing information. MTS should be discontinued if ACD is suspected.

Patch testing in allergic contact dermatitis

A deterioration in chronic inflammatory ear disease despite topical medication, or failure of the condition to improve with such treatment, should raise the possibility of allergic contact dermatitis. Allergen testing (patch testing) is the ‘gold standard’ method of identifying an agent causing allergic contact dermatitis.

We describe an ENT patch test series applied by our department as a screening device for this condition.

Interferon-γ secreted from peripheral blood mononuclear cells as a possible diagnostic marker for allergic contact dermatitis to gold

10% of patch-tested patients have a positive reaction to gold. Most lack clinical symptoms, but allergic contact dermatitis (ACD) to gold is increasing. In this study, 77 dermatological outpatients were divided into 3 groups depending on epicutaneous patch test outcomes: a group positive to gold (EPI+), a group negative to gold (EPI-), and a group with irritant reactions to gold (EPI-IR). Lymphocytes were stimulated in vitro with gold sodium thiosulfate. Proliferation was assessed using the lymphocyte transformation test (LTT), and cytokine secretion was assessed using a multibead array (Luminex; Linco Research Inc., St. Charles, MO, USA), in order to evaluate whether an in vitro method with high diagnostic accuracy could be devised. The EPI+ group showed a significantly increased secretion of interferon (IFN)-gamma, interleukin (IL)-2, and IL-13 and also showed a significantly higher stimulation indexes for LTT, compared to the other 2 subject groups. Sensitivity and specificity were calculated for all methods individually and combined, but IFN-gamma assessment alone was the most accurate method for identifying ACD to gold, with sensitivity and specificity of 81.8% and 82.1%, respectively. This method also identified 87.5% of the EPI-IR subjects as non-allergic. Therefore, assessment of secretion of IFN-gamma should be a valuable complement to patch test for diagnosing gold allergy.

Allergic contact dermatitis

The pathophysiology of ACD follows an intricate design and results in the characteristic, delayed inflammatory response. Although the astute physician may correctly diagnose ACD from its initial, classic history and presentation, alternative diagnoses should be considered and excluded. Patch testing performed with a relevant panel of contact allergens is the ultimate confirmatory test of ACD. Correctly identifying the inciting allergen permits appropriate personal avoidance. Corticosteroids remain the principal treatment options.

Atopy and contact hypersensitivity: a reassessment of the relationship using objective measures

BACKGROUND

There is a big contradiction in the medical literature regarding the relationship between atopy and contact hypersensitivity. Some researchers believe that atopy would prevent, whereas others believe that it would promote, the development of contact allergy. Possible causes of this confusion range from different study populations to different definitions of atopy.

OBJECTIVE

To evaluate the relationship between atopy and contact hypersensitivity in a well-defined general population sample using objectively measurable markers.

METHODS

I studied 135 randomly selected students from 5 vocational schools: 73 women and 62 men aged 18 to 19 years. The following atopy markers were tested: positive skin prick test results, positive Phadiatop test results, and total IgE levels greater than 120 kU/L. Contact hypersensitivity was detected by using patch tests. Statistical analyses included the Fisher exact test, the Mann-Whitney U test, and calculation of odds ratios.

RESULTS

At least 1 positive skin prick test result was found in 23.7% (95% confidence interval [CI], 16.5%-30.9%) of study participants, positive Phadiatop test results were found in 20.0% (95% CI, 13.3%-26.7%), and total IgE levels greater than 120 kU/L were found in 23.7% (95% CI, 16.5%-30.9%). Positive patch test reactions were found in 28.1% (95% CI, 20.6%-35.7%) of participants, most frequently to thimerosal (18.5%; 95% CI, 12.0%-25.1%) and nickel (9.6%; 95% CI, 4.6%-14.6%). For persons with atopy markers, odds ratios for contact hypersensitivity ranged from 1.0 to 3.2, the highest being for nickel hypersensitivity among those with total IgE levels greater than 120 kU/L. None of these relationships were statistically significant.

CONCLUSION

Atopy and contact hypersensitivity are independent phenomena.

Allergic contact dermatitis in Iran

The frequency of sensitization to contact allergens varies in different countries because of both genetic and, more importantly, allergen exposure variations. The objective is to determine the frequency of sensitization to contact allergens in Iranian patients with dermatitis. 250 patients with a clinical diagnosis of contact dermatitis and/or atopic dermatitis were evaluated with a 28-allergen screening series recommended by the German Contact Dermatitis Research Group from September 2002 to April 2004 in Tehran, Iran. The patches were applied on the back of the patients, removed after 24 hr and the readings were taken on 24 hr, 48 hr and 72 hr after application. 126 patients (50.4%) showed at least 1 positive reaction, and 23 patients (9.2%) had more than 2 positive reactions. 189 (84.4%) of 224 positive reactions had past and/or present clinical relevance. The 5 most common allergens were nickel sulfate 70 (28.0%), cobalt chloride 32 (12.8%), para-tertiarybutyl phenol formaldehyde resin 20 (8.0%), potassium dichromate 13 (5.2%) and colophony 13 (5.2%). Contact allergy to nickel sulfate was significantly more common in female patients and in patients under 40 years of age (P < 0.05). Nickel sulfate is the most common contact allergen in Iran, mostly affecting women and younger patients probably because of more exposure.

Topical pimecrolimus in the treatment of human allergic contact dermatitis

BACKGROUND

Contact dermatitis is a common clinical problem, with prevalent sensitizers being cosmetics, metals, medicines, and plants. Plants of the Toxicodendron species cause allergic contact dermatitis (ACD) in 50% to 70% of the population. Pimecrolimus is an ascomycin macrolactam developed for the treatment of inflammatory skin diseases and approved by the US Food and Drug Administration for atopic dermatitis. There are studies supporting the effectiveness of macrolactams when administered before antigen challenge, but there are no studies describing the effectiveness of these drugs in the treatment of established human ACD.

OBJECTIVE

To investigate the effect of topical pimecrolimus in the treatment of Toxicodendron-induced ACD once rash is evident.

METHODS

Poison ivy tincture was applied to the bilateral anterior forearms of 12 subjects with Finn Chambers (Allerderm Diagnostic Products, Petaluma, CA). After dermatitis was evident, volunteers treated each arm twice daily with either 1% topical pimecrolimus cream or placebo in a blinded fashion. Outcomes measured were a dermatitis grading score and time to rash and itch resolution.

RESULTS

The median +/- SEM time for rash resolution was 16.55 +/- 1.59 days in the treatment group and 16.27 +/- 1.82 days in the placebo group (P = 0.601). The median time for itch resolution was 4.73 +/- 1.56 days in the treatment group and 4.91 +/- 1.59 days in the placebo group (P = 0.167). The average dermatitis score was 2.26 +/- 0.17 in the treatment group and 2.32 +/- 0.15 in the placebo group (P = 0.62).

CONCLUSIONS

The application of topical pimecrolimus is ineffective in the treatment of ongoing Toxicodendron-induced ACD.

Evaluation of the histologic characteristics of patch test confirmed allergic contact dermatitis

BACKGROUND

Microscopic features of experimentally induced allergic contact dermatitis (ACD) have been reported; however, the histologic characteristics of environmentally induced ACD have not been definitively elucidated.

OBJECTIVE

This pilot study was conducted to describe the histologic features most useful in differentiating ACD from other forms of eczematous dermatitis.

METHODS

A retrospective chart review of patients who underwent evaluation for contact dermatitis was performed. The results of skin biopsy were reviewed in a blinded manner, and two subgroups were compared: gold standard ACD cases and control cases (eczematous dermatitis with negative results of patch testing).

RESULTS

Of 317 cases reviewed, 39 fulfilled the inclusion criteria. Many histologic similarities were noted: both subgroups had substantial acanthosis and lymphocytic infiltration. In addition, present to a moderate degree in both groups were hyperkeratosis, spongiosis, eosinophils, and dermal dendritic fibrohistiocytic (DFH) cells. However, compared with the control cases, eosinophilic spongiosis and multinucleate dermal DFH cells were found to a considerably greater degree in the standard ACD cases.

CONCLUSIONS

Eosinophilic spongiosis and multinucleate dermal DFH cells, in the presence of acanthosis, lymphocytic infiltrate, dermal eosinophils, and hyperkeratosis, are particularly suggestive of ACD. While such findings alone are not diagnostic of ACD, the presence of these combined histologic features supports the pursuit of patch testing in cases of chronic eczematous dermatitis.

Patch testing for allergic contact dermatitis in the allergist office

The identification of allergens responsible for allergic contact dermatitis (ACD) is key to the management of this disease. The patch test (PT) is the only safe, objective, scientific, and practical method for the diagnosis of ACD. There is no single PT panel that will screen all the relevant allergens in a patient's environment. It is generally thought that 20 to 30 allergens in routine screening tests can identify 50% to 70% of clinically relevant ACD. However, the usefulness of patch testing is enhanced with the number of allergens tested. Although the PT might be simple to apply, it might be difficult to read, interpret, and correlate to the patient's symptoms. A familiarity with the patient's environment, the process of the industry in that environment, and the uses of various chemicals in the industry is needed in most cases.

Occupational dermatoses

PURPOSE OF REVIEW

All terms referring to job-related (occupational) rashes are clearly defined. Ranking as the second most common occupational disorder, the importance of occupational dermatoses is illustrated.

RECENT FINDINGS

90-95% of occupational dermatoses result from a contact-type dermatitis. Until recently, 4/5 cases were believed to be of the irritant, rather than allergic type of contact dermatitis, however, with more extensive patch testing, more than half the cases were found to be allergic.

SUMMARY

The direct causes of occupational dermatoses: chemical, mechanical, physical, and biological in nature are presented. The implications of assigning the degree and type of occupational dermatoses are explained. Workmans compensation is based on a no-fault arrangement, stating that unrestricted treatment and compensation is allowable only when negligence on the part of the employer is proven. Employee benefits are then determined by the duration and degree of disability sustained - all of which becomes litigational. Predisposing host factors, i.e. intellectual ability, anatomic site, atopy, skin pigmentation, age of skin, and immunosuppression (by disease or medication) are usually ignored. Environmental factors at the workplace must be considered conducive to occupational diseases. The full spectrum of irritant contact dermatitis is discussed with examples of each described. Allergic contact dermatitis and patch testing - the gold standard for identification of putative allergens is extensively discussed. Differentiating irritant contact dermatitis from allergic contact dermatitis is elucidated. The other non-contact type skin reactions are briefly mentioned.

Allergic otitis externa

Chronic otitis externa is a common condition, which is usually successfully treated by topical medications and aural toilet. In cases that persist despite conventional treatment, a diagnosis of allergic otitis externa should be considered. Sensitization to otic medications (secondary contact otitis) is not uncommon. Topical aminoglycosides are the most common sensitizers although many components of topical preparations can cause sensitization. Patients who may have developed allergic otitis externa should undergo patch testing. Otolaryngologists should consider using topical antibiotics with a low allergenic potential and avoiding neomycin when treating patients with otitis externa. Primary contact otitis may occur to metals used in earrings and also to hearing aid moulds. Treatment of both primary and secondary contact otitis consists of identifying the allergen, avoiding further contact and use of simple preparations avoiding common sensitizers.

Eyelid dermatitis

Cosmetic alteration of a patient's orbital skin is a common reason for professional consultation. This review presents the differential diagnosis and recommended evaluation of inflamed eyelids. To better understand the diseases, each is individually addressed clinically, pathogenetically, and therapeutically. It is critical to recognize the lesions correctly and to have full knowledge of the putative clinical disease process. An algorithm for an appropriate work-up for each disease is offered. With this background, a successful therapeutic response can be anticipated.

Prevalence of delayed hypersensitivity to the European standard series in a self-selected population

There are limited reports of the prevalence of positive reactions in healthy adults to patch tests with standard allergens; there are no recent comprehensive studies from Australia. Healthy adult volunteers (n = 219) from the Western Australian community were patch tested using the European standard series of allergens. Seventy-seven (35%) reacted to at least one allergen, positive patch tests being most prevalent to nickel sulfate (20%), potassium dichromate (9%), cobalt chloride (6%) and fragrance mix (4%). Prevalence of positive patch tests to nickel and chromate was higher than that reported for another healthy population, which may stem from self-selection of volunteers or geographical differences, including extent of exposure to allergens.

Contact reactions to fragrances

BACKGROUND

The most common reaction to fragrances is contact dermatitis, a delayed hypersensitivity reaction; however, other reactions include immediate contact reactions (contact urticaria) and photo-allergic reactions. Fragrance mix (FM) and balsam of Peru (BP) are used to screen for fragrance allergy.

OBJECTIVE

To study the different types of allergic skin reactions to fragrance compounds.

METHODS

Delayed hypersensitivity reactions to FM and BP were studied in 4,975 patients with suspected contact dermatitis by routine patch testing interpreted at 48 and 96 hours. In 664 of the patients, patch tests were read at 30 minutes to evaluate for immediate (wheal-and-flare) contact reactions and again at 48 and 96 hours. Photopatch tests to FM were performed in 111 patients with suspected photo-allergic dermatitis.

RESULTS

Delayed contact reactions to FM occurred in 6.6% of females and 5.4% of males and to BP in 3.9% of females and 4.1% of males. Analysis of data over time (12 study years) showed an increased trend for reactions to fragrances, particularly in males. Sensitivity to other contact allergens (polysensitivity) was found in 62% of patients and polysensitivity presented more often with generalized contact dermatitis. The most sensitizing components of the fragrance mix that were tested in 38 patients were cinnamic alcohol, oak moss, and cinnamic aldehyde. There were 112 immediate patch test reactions to FM and 113 to BP in 664 patients. Immediate contact reactions were followed by delayed contact reactions in 13.4% of patients for FM and 8.8% for BP, representing a significant increase in the frequency of delayed contact reactions. Patients with immediate contact reactions to fragrances did not have a higher incidence of atopy (25.9%). No cases of positive photopatch test reactions to FM were seen.

CONCLUSION

Fragrances commonly cause both delayed and immediate patch test reactions and patients with immediate contact reactions have an increase in delayed contact reactions to the same allergen.

Allergic dermatoses

Defining "allergy" and elucidating the immunopathology of what is too often described as allergic rashes is the objective of this article. The differentiation of inflammatory reactions, which at times is indistinguishable from the immunologic dermatoses is outlined. A rationale plan for management, with indications warranting referral to "the specialist" are suggested.