Prevalence of Contact Allergy to Nickel: A Retrospective Chart Review.

BACKGROUND: No recent studies reporting nickel sensitivity prevalence in Canadians exist. OBJECTIVES: The aim of this study was to quantify nickel sensitivity prevalence in patients at a patch test clinic in Vancouver. METHODS: Retrospective chart review of 3263 patients patch tested for nickel sensitivity at our clinic in Vancouver between 2008 and 2020. RESULTS: In total, 24.3% (n = 792 of 3263) of patients were sensitive to nickel. Nickel sensitivity significantly increased over time from 24.3% to 27.9% from 2008 to 2020. Nickel-sensitive patients were significantly more likely to be women (P < 0.001), between the ages of 19 and 64 years (P = 0.010), and have dermatitis affecting the face (P = 0.001) and hands (P = 0.001). Nickel-sensitive patients were significantly less likely to be 65 years or older (P = 0.001) and have dermatitis affecting the legs (P = 0.002). Approximately half of nickel-sensitive reactions were new positive reactions at the second reading. CONCLUSIONS: Nickel sensitivity occurred in approximately one quarter of patients and significantly increased over time. Nickel-sensitive patients were more likely to be women, aged 19 to 64 years, and have dermatitis affecting the face and hands; and less likely to be 65 years or older and have dermatitis affecting the legs.

Approach to allergic contact dermatitis caused by topical medicaments.

OBJECTIVE: To provide an approach to identifying topical medicament ingredients that cause allergic contact dermatitis (ACD) and to recognizing common clinical scenarios in which these ingredients might present. SOURCES OF INFORMATION: A retrospective chart review was conducted of patients patch tested at the Contact Dermatitis Clinic at St Paul's Hospital in Vancouver, BC, between November 2016 and June 2019. Data from the North American Contact Dermatitis Group from 2015 to 2016 and The Ottawa Hospital patch test clinic from 2000 to 2010 were also reviewed. MAIN MESSAGE: Topical antibiotics are the most common cause of ACD to medicaments and frequently cause cosensitization to multiple allergens. This hypersensitivity reaction is often seen following surgical procedures and should be distinguished from postoperative infection. Corticosteroid allergy is easy to miss and should be suspected in cases of corticosteroid-sensitive dermatoses that worsen despite appropriate treatment. Topical anesthetics and propylene glycol are other causes of ACD found in many prescription and over-the-counter products. CONCLUSION: Allergic contact dermatitis is easy to miss and should always be considered in cases of eczematous eruptions. A thorough drug history including all topical products-both prescription and over-the-counter-is critical. Patch testing can help identify specific allergens for the patient to avoid.

Approche de la dermatite de contact allergique causée par les médicaments topiques.

OBJECTIF: Fournir une approche pour déterminer quels sont les ingrédients contenus dans les médicaments topiques qui causent la dermatite de contact allergique (DCA) et reconnaître les scénarios cliniques courants où ces ingrédients pourraient être présents. SOURCES D'INFORMATION: Revue rétrospective des dossiers de patients ayant subi un test épicutané à la clinique de dermatite de contact de l'Hôpital Saint-Paul à Vancouver, en Colombie-Britannique, entre les mois de novembre 2016 et juin 2019. Ont également été évaluées, les données de 2015 à 2016 du North American Contact Dermatitis Group et celles de 2000 à 2010 de la clinique de test épicutané de l'Hôpital d'Ottawa. MESSAGE PRINCIPAL: Les antibiotiques topiques sont la cause la plus courante de DCA aux médicaments, et ils causent fréquemment la cosensibilisation à plusieurs allergènes. Cette réaction d'hypersensibilité survient souvent après une intervention chirurgicale, et il faut la différencier de l'infection postopératoire. L'allergie aux corticostéroïdes est facile à manquer, et il faut la soupçonner dans les cas de dermatose sensible aux corticostéroïdes qui s'aggravent malgré le traitement approprié. Les anesthésiques et le propylèneglycol topiques, trouvés dans de nombreux produits d'ordonnance ou en vente libre, sont d'autres causes de DCA. CONCLUSION: La dermatite de contact allergique est facile à manquer et doit toujours être envisagée dans les cas d'éruption eczémateuse. Il est essentiel d'établir l'historique des médicaments, dont tous les produits topiques d'ordonnance ou en vente libre. Le test épicutané contribue à déterminer quels allergènes spécifiques le patient doit éviter.

Atopy Associated With Positive Patch Test and Possible Allergic Contact Dermatitis.

BACKGROUND: Atopy is a genetic predisposition to the development of allergic reactions and the increased production of immunoglobulin E (IgE) upon exposure to environmental antigens. Clinical manifestations of atopy include asthma, atopic dermatitis (AD), and allergic rhinoconjunctivitis (ARC). OBJECTIVE: To determine if cutaneous delayed hypersensitivity reactions (CDHRs) as assessed by patch testing are higher among patients with a history of atopy and with a familial predisposition to atopy. METHODS: For this study, we reviewed the patch test database of the UBC Contact Dermatitis Clinic over a 4-year time span. A personal history of asthma, AD, and ARC was recorded. In addition, a family history was obtained and manifestations of atopy in family members were noted. RESULTS: A total of 1515 patients were included in this study. Our data show that the odds ratio (OR) of a positive patch test with a personal history of atopy was 1.39, while the OR of a positive patch test with a family history of atopy was 1.69. Conversely, a personal history of respiratory atopy did not significantly affect the probability of a positive patch test, with an OR of 1.03. CONCLUSION: We conclude from our study that patients with a personal or family history of atopy have an increased risk of allergic contact dermatitis (ACD). These results provide further evidence for the link between atopy and ACD and suggest that children of atopic parents should avoid potential contact allergens and would likely benefit from prophylactic emollient use.

Methylisothiazolinone Contact Allergy Prevalence in Western Canada: Increased Detection With 2000 ppm Patch Test Allergen.

BACKGROUND: Contact allergy to methylisothiazolinone (MI) or to the combination of methylchloroisothiazolinone and MI (MCI/MI) is an important and increasing cause of allergic contact dermatitis, with prevalence rates higher than 10% in some centers. OBJECTIVES: The objective of this retrospective chart review is to provide a western Canadian perspective on whether the positive patch testing rate to MCI/MI or MI increased during the testing period of 2008 to 2015 and whether the addition of MI at 2000 ppm resulted in increased detection. METHODS: We conducted a retrospective chart review of patients who tested positive (n = 104) of 2177 total patients who were patch tested for MCI/MI or MI at a community dermatology clinic in Vancouver, British Columbia, Canada, from January 2008 through April 2015. RESULTS: One hundred and four patients had positive patch testing results for MCI/MI, MI, or both. Positive results increased over the study period, with the highest prevalence in 2015 at 9.41% for MCI/MI, 12.94% for MI, and 15.29% for either. When testing for MI at 2000 ppm was introduced in 2013, the initial positive patch testing prevalence was 6.6%, followed by 10.1% in 2014, and 12.9% in 2015. CONCLUSIONS: We demonstrate an increasing prevalence of MCI/MI and MI allergy between 2008 and 2015, with the highest prevalence of 15.29% in 2015 for MCI/MI and/or MI allergy. The addition of MI 2000 ppm greatly increased the positive patch testing yield for MI. Our results support the importance of continued efforts to monitor and regulate these preservatives.

Decreasing Rates of Neomycin Sensitization in Western Canada.

BACKGROUND: Neomycin contact sensitization rates in North America range from 7% to 13%, whereas in Europe they average approximately 1.9%. OBJECTIVES: Given that topical neomycin products are no longer readily available in Canada, the aim of this study was to examine what influence this may have had on neomycin sensitization rates in the 3 western provinces. METHODS: On the basis of an observation originally communicated by L. M. Parsons and C. Zhang of the University of Calgary, which suggested significantly reduced rates of neomycin sensitization in Calgary, Alberta, Canada, a multicenter study of patch test results from 5690 patient charts was undertaken. Data from 3 other western Canadian Universities (the University of Saskatchewan, the University of Alberta, and the University of British Colombia) were analyzed. Data were available from 2001 to 2013 for the University of Saskatchewan (except 2006), whereas the University of Alberta and the University of British Columbia had data from 2009 to 2013. Descriptive statistics, trend analysis, and risk estimates were determined using SPSS version 20. RESULTS: Sensitization rates for neomycin have decreased in western Canada and are now similar to those of Europe. CONCLUSIONS: This trend is likely influenced by the reduced availability of over-the-counter and prescription neomycin products in Canada.

Lidocaine contact allergy is becoming more prevalent.

BACKGROUND: Allergic contact dermatitis (ACD) to lidocaine is rising in prevalence. This is due to a growing number of over-the-counter (OTC) products containing topical amide and ester anesthetics. The phenomenon poses a real threat to the authors' surgical anesthetic options. OBJECTIVE: To investigate the epidemiology of topical anesthetic ACD in British Columbia, Canada and provide an approach for clinicians to deal with this problem. MATERIALS AND METHODS: A retrospective chart review of 1,819 patients who underwent patch testing at the University of British Columbia Contact Dermatitis Clinic between January 2009 and June 2013 was completed. The authors also performed a detailed review of Canadian OTC preparations containing lidocaine in 2013. RESULTS: The prevalence of ACD to local anesthetics is significant at 2.4%. The most common allergen is benzocaine (45%) followed by lidocaine (32%) and dibucaine (23%). CONCLUSION: The proportion of ACD caused by lidocaine is higher than expected. This is likely secondary to an increase in OTC medicaments containing lidocaine. Patients who are patch test-positive to a local anesthetic should be challenged intradermally to confirm clinical relevance. Because ACD is a delayed Type IV hypersensitivity reaction (localized dermatitis), the risk of anaphylaxis is not a concern.

Analysis of the prevalence of allergic contact dermatitis to sunscreen: a cohort study.

BACKGROUND: As the use of sunscreens becomes more prevalent, reports of adverse effects to sunscreens have increased. OBJECTIVE: To analyze a patch test database for the prevalence of allergic contact dermatitis (ACD) to sunscreen. METHODS: The database was searched for positive patch test reactions to benzophenone-3. Charts were also reviewed for those who were further tested to the sunscreen series. RESULTS: Twenty-three of the 1,527 patients seen were tested to the sunscreen series. Of these, only 4 patients had a positive reaction to a sunscreen chemical or to the product they were using. In addition, 8 of the 1,527 patients who had no specific history of sunscreen allergy reacted to benzophenone-3. CONCLUSION: ACD to sunscreen was found to be very uncommon (0.8%). Other final diagnoses included ACD to excipients such as fragrances or preservatives and suspected photosensitive disorders.

Friction-induced pagetoid dyskeratosis.

BACKGROUND: Pagetoid dyskeratosis (PD) is characterized by pale cells within the epidermis resembling those of Paget disease. These cells have been seen as an incidental finding in a variety of benign papules most commonly located in intertriginous areas. The lesion is considered a reactive process in which a small proportion of the normal population of keratinocytes is altered. Among the triggers for this lesion, friction has been suggested; however, a direct cause-and-effect relationship has not yet been reported. RESULTS: We confirmed the relationship between PD and friction in a biopsy taken from a 19-year-old woman who presented with clinical features indicating exogenously induced bullae and erosions and consented to a biopsy of a lesion immediately after its induction, demonstrating combined features of PD and friction bulla.

The health controversies of parabens.

Parabens are preservatives used in a variety of personal care, cosmetic, pharmaceutical and food products. Studies have confirmed the ubiquitous presence of parabens, with levels detected in wastewater, rivers, soil and house dust. Parabens have also been detected in human tissues and bodily fluids, but it is the discovery of these chemical compounds in the breast tissue of patients with breast cancer that has raised public concern over their use. It is hypothesized that the estrogenic properties of parabens may play a role in breast cancer development. However, studies investigating the health effects of parabens are conflicting. At this point, there is an insufficient amount of data suggesting serious consequences from paraben use and exposure to warrant drastic avoidance measures or government regulations.

Allergic contact dermatitis to preservatives and fragrances in cosmetics.

Cosmetics are an important cause of allergic contact dermatitis (ACD). Fragrances and preservatives are the two most clinically relevant allergens found in cosmetic products. Patch testing remains the gold standard for identification of causative allergens. Common cosmetic allergens are reviewed. Practical methods of allergen avoidance are also discussed.

HIV dermatology in Canada: cutaneous disease burden and demographic characteristics of a specialized urban practice.

BACKGROUND: The introduction of antiretroviral therapies has changed the pattern of cutaneous disease in individuals infected with human immunodeficiency virus (HIV). OBJECTIVE: To assess demographic characteristics, severity of immunosuppression, and frequency of dermatologic disorders in patients presenting to a Canadian specialized HIV dermatology practice. METHODS: A cross-sectional study was performed of 183 consecutive outpatient and inpatient consultations to a single HIV dermatology practice from January 2007 to December 2008. RESULTS: One hundred sixty-three (88%) patients were male, with an average age of 45. Forty-six patients were not on antiretroviral therapy. Verruca was the most common diagnosis, seen in 29 patients, followed by dermatophyte infection, seen in 27. Patients with a low CD4 count (p  =  .0001) and a high viral load (p  =  .0043) were more likely to present with an HIV-specific dermatosis. CONCLUSION: Cutaneous infections were the most common diagnoses in this cross section. Classic HIV dermatoses were seen more frequently in those with more advanced disease owing to HIV infection.

Psoriasis and pustular dermatitis triggered by TNF-{alpha} inhibitors in patients with rheumatologic conditions.

BACKGROUND: New onset or worsening of psoriasis has been reported in patients treated with tumor necrosis factor alpha (TNF-alpha) inhibitors for a variety of rheumatologic conditions. There is mounting evidence that a key innate immune pathway for triggering common human autoimmune disease, including psoriasis, involves plasmacytoid dendritic cell precursors (PDCs) and type 1 interferon (IFN) production. We present herein a case series with clinical and histopathologic evidence of psoriasis in patients with rheumatologic disease treated with TNF-alpha inhibitors. We propose that the cross regulation between TNF-alpha and IFN may have a role in the pathogenesis of this reaction. OBSERVATIONS: We observed new-onset psoriasis (n = 13) or severe exacerbation of psoriasis (n = 2) in 15 patients with a variety of rheumatologic conditions-rheumatoid arthritis (n = 13), psoriatic arthritis (n = 1), and seronegative arthritis (n = 1)-during treatment with etanercept (n = 6), infliximab (n = 5), and adalimumab (n = 4). Immunohistochemical staining of skin biopsy specimens for myxovirus-resistance protein A (MxA, a surrogate marker for lesional type 1 IFN activity) showed increased staining in TNF-alpha inhibitor-induced psoriasis compared with psoriasis vulgaris. CONCLUSIONS: New onset or severe exacerbation of psoriasis is a rare complication of TNF-alpha inhibitor therapy. The finding of increased production of IFN-alpha in TNF-alpha inhibitor-induced psoriasis is a possible pathophysiologic explanation for this reaction.

Topical therapies for psoriasis: evidence-based review.

OBJECTIVE: To review current understandings of and approaches to topical psoriasis therapies and to assess their efficacies and adverse effects. QUALITY OF EVIDENCE: Literature from 1987 to 2003, inclusive, was reviewed via MEDLINE using the search term "psoriasis" combined with "topical treatment." Articles were prioritized based on their level of evidence, favouring double-blind, randomized controlled trials over other comparison studies. Other studies were included where level I research was unavailable. No level III research was included. MAIN MESSAGE: Psoriasis is very common and causes substantial morbidity. Because most psoriasis is mild to moderate, patients are well suited to outpatient topical therapy. Advances in topical treatments for psoriasis have kept pace with a rapidly evolving comprehension of its pathogenesis, making a review of current therapies useful for those who treat psoriasis. While research supports continued reliance on corticosteroids as first-line therapy, comparable efficacy has been shown for vitamin D analogues and topical retinoids, albeit with a slight increase in adverse effects. CONCLUSION: The combination of steroids and vitamin D analogues or topical retinoids is perhaps the most promising current treatment. It seems to have increased efficacy and fewer side effects.

Early detection of skin cancer by family physicians: a pilot project.

BACKGROUND: Malignant melanoma is rising quickly in incidence and mortality rates. Family physicians (FPs) have been reported to lack confidence in diagnosing skin cancers. OBJECTIVE: The aim of this study was to determine whether an educational intervention can improve FPs' abilities to diagnose skin cancers. METHODS: The design was a prospective, randomized trial which included a skin cancer questionnaire, a video intervention, and a skin biopsy review. RESULTS: Pre-intervention, FPs answered 57% of the questions correctly on the skin cancer questionnaire. Post-intervention, the video intervention group scored higher than did the control group. The video intervention group removed 10% fewer benign lesions and almost 3 times more malignant lesions compared with their pre-intervention biopsy rate. No findings were statistically significant. CONCLUSION: An educational intervention may improve FPs' knowledge and diagnosis of skin cancer. Our results may guide future studies with larger sample sizes in developing a skin cancer continuing medical education (CME) course for FPs.