Contact allergy in Swedish professional ice hockey players.

BACKGROUND: Professional ice hockey players may contract irritant and allergic contact dermatitis. AIMS: To investigate the presence of contact allergy (CA) in professional ice hockey players in Sweden. METHODS: Ten teams from the two top leagues were assessed for potential occupational exposure to sensitizers. Exactly 107 players were patch tested with an extended baseline series and a working series, in total 74 test preparations. The CA rates were compared between the ice hockey players and controls from the general population and dermatitis patients. RESULTS: One out of 4 players had at least one contact allergy. The most common sensitizers were Amerchol L 101, nickel and oxidized limonene. CA was as common in the ice hockey players as in dermatitis patients and significantly more common than in the general population. Fragrances and combined sensitizers in cosmetic products (fragrances + preservatives + emulsifier) were significantly more common in ice hockey players compared with the general population. CONCLUSION: The possible relationship between CA to fragrances and cosmetic products on the one hand and the presence of dermatitis on the other should be explored further.

Professional Cleaners' and Healthcare Workers' Ability to Recognize Hand Eczema.

Timely intervention reduces the risk of a poor prognosis in hand eczema, making early recognition of symptoms important in high-risk professions. However, limited data exist regarding the ability of cleaners and healthcare workers to recognize hand eczema. The aim of this study was to examine cleaners' and healthcare workers' ability to recognize hand eczema in clinical photographs and to assess the severity of the disease. Cleaners and healthcare workers completed a questionnaire consisting of 16 questions and participated in a structured interview referring to a validated photographic severity guide for chronic hand eczema, which comprised clinical photographs of hand eczema at varying levels of severity. Eighty cleaners and 201 healthcare workers (total N = 281) participated in the study. The rates of correctly identified hand eczema in clinical photographs (cleaners/ healthcare workers) were: 41.2%/57.7% (mild hand eczema), 81.2%/92.0% (moderate hand eczema), 85.0%/94.5% (severe hand eczema) and 82.5%/97.0% (very severe hand eczema). The proficiency of healthcare workers in recognizing hand eczema was significantly higher than that of cleaners. The results indicate that a large proportion of cleaners and healthcare workers fail to recognize mild hand eczema in clinical photographs. Healthcare workers had higher success rates in recognizing hand eczema in all severity categories. Symptom underestimation may lead to under-reporting of the true prevalence of hand eczema, with consequent loss of opportunities for prevention.

Notification of hand eczema as an occupational disease among Danish hairdressers: a national survey on patients' perception.

OBJECTIVES: Self-reported hand eczema was previously found under-reported as an occupational disease to the authorities among Danish hairdressers graduating from 1985 to 2007. This study investigates whether self-reported hand eczema among Danish hairdressers graduating from 2008 to 2018 is under-reported as an occupational disease to the authorities. METHODS: A cross-sectional study on all Danish hairdressers graduating from 2008 to 2018 was conducted. The participants were identified using information from the Danish Hairdressers' and Beauticians' Union. In May 2020, a self-administered survey on hand eczema was sent to all hairdressers. RESULTS: A response rate of 30.7% (1485/4830) was obtained. The lifetime prevalence of self-reported hand eczema was 40.1%, and 84.1% of hairdressers with hand eczema believed it to be occupational of whom 27.0% answered it was reported as an occupational disease to the authorities. Of hairdressers believing their hand eczema was occupational, consulting a doctor and answering it was reported as an occupational disease, 94.4% had consulted a dermatologist. The main reason for not reporting was 'I would probably not gain anything from it anyway' (40.0%). CONCLUSIONS: Based on hairdressers' perception, occupational hand eczema still seems to be an under-reported disease which may lead to underestimation of the problem and impair prevention, diagnosis and treatment.

Prevalence of Occupational Contact Dermatitis Among Dental Personnel Using the Nordic Occupational Skin Questionnaire-2002: A Prospective Cross-Sectional Study.

BACKGROUND: Occupational skin disease (OSD), such as contact dermatitis, is widespread among dental professionals; however, reports regarding its prevalence have inconsistent findings and methodology. Therefore, we conducted a cross-sectional survey using a self-reported questionnaire to estimate the prevalence of work-related and occupational exposure-induced skin diseases. METHODOLOGY: A self-administered questionnaire, based on the validated Nordic Occupational Skin Questionnaire-2002, was distributed to 15 dental clinics in Israel in the first half of 2022. The questionnaire included questions about the occupation, exposure, and history of atopic disease, dry skin, and hand/arm and wrist eczema, as well as participant demographics. RESULTS: Overall, 312 dental professionals completed the questionnaires. Response rate was 80%. The lifetime prevalence of self-reported skin symptoms was 19.23%. Significant risk factors included exposure to metal objects, odds ratio (OR): 2.43, 95% confidence interval (CI): [1.02, 5.78]; p < .05, dry skin (OR: 3.54, 95% CI: [1.93, 6.5]; p < .001), itching when sweating (OR: 2.89, 95% CI: [1.39, 6]; p < .05), contact urticaria (OR: 10.67, 95% CI: [4.46, 25.49]; p < .001), hay fever (OR: 2.25, 95% CI: [1.14, 4.42]; p < .05), allergic symptoms (OR; 2.33, 95% CI: [1.18, 4.58]; p < .05), and asthma (OR: 4.8, 95% CI: [2.17, 10.36]; p < .001). CONCLUSIONS: This is the first study to use the NOSQ-2002 among dental professionals. Our study provides a better understanding of the prevalence and consequences of OSDs among dental personnel by utilizing the validated tool NOSQ-2002.

New causes of occupational allergic contact dermatitis.

PURPOSE OF REVIEW: Occupational allergic contact dermatitis (OACD) is an important work-related skin disease. Information about the causative agents comes from many sources, including patch test databases, registries, case series and case reports. This review summarizes new information about common causative allergens and diagnosis. RECENT FINDINGS: Common causes of OACD include rubber components, epoxies and preservatives. New exposure sources for these allergens continue to be described. Often these exposure sources are related to the changing world around us, such as allergens related to smartphones and technology, and personal protective equipment-related exposures during the COVID-19 pandemic. New allergens are also being described, some of which are related to known allergens (e.g. a new epoxy or acrylate component).Accurate diagnosis is critical to effective management of OACD, which may include removing the worker from exposure to the causative allergen. Safety data sheets may not contain complete information and patch testing with specialized series of allergens and workplace materials may be necessary. SUMMARY: This review provides current evidence about causes of OACD and important aspects of diagnosis. This is important for clinical practice to ensure cases of OACD are not missed.

Sensitization to ethylenediamine dihydrochloride in patients with contact dermatitis in northeastern Italy from 1996 to 2021.

BACKGROUND: Ethylenediamine dihydrochloride is a versatile aliphatic amine found in numerous medications and industrial compounds and is a known sensitiser. The sensitization prevalence is affected by geographical and socio-cultural factors. OBJECTIVES: The objectives are to analyse the temporal trend of sensitization to ethylenediamine dihydrochloride in northeastern Italy and to investigate associations with occupations. METHODS: Between 1996 and 2021, 30 629 patients with suspected allergic contact dermatitis were patch tested with the Triveneto baseline series. Individual characteristics were collected through a standardised questionnaire. RESULTS: The overall prevalence of ethylenediamine dihydrochloride sensitization was 1.29% with percentages similar in both sexes. We observed a significant decreasing trend over time (p < 0.001), yielding a sensitization prevalence <1% in recent years. Among departments, residence in Pordenone area was protective for sensitization. No significant associations were observed with specific occupations. We found significant associations between ethylenediamine dihydrochloride sensitization and being 26-35 years old (odds ratio [OR], 1.47; 95% confidence interval [CI]: 1.05-2.08), and sensitization for many haptens, such as paraben mix (OR, 5.3; 95% CI: 3.3-8.5), epoxy resin (OR, 5.1; 95% CI: 3.0-8.7), neomycin sulphate and mercaptobenzothiazole. CONCLUSIONS: Our study showed a downward time trend of ethylenediamine dihydrochloride sensitization in northeastern Italian population and pointed to an update of the Triveneto baseline series.

Trends in occupational and work-related contact dermatitis attributed to nickel, chromium and cobalt in the UK: findings from The Health and Occupation Research network 1996-2019.

BACKGROUND: Occupational exposure to metals such as nickel, chromium and cobalt can be associated with contact dermatitis, which can adversely affect an individual's health, finances and employment. Despite this, little is known about the incidence of metal-related occupational contact dermatitis over prolonged periods of time. OBJECTIVES: To investigate the medically reported trends in the incidence of work-related contact dermatitis attributed to nickel, chromium and cobalt in the UK. METHODS: Incidence and trends in cases of occupational contact dermatitis caused by nickel, chromium or cobalt between 1996 and 2019 (inclusive), reported to the EPIDERM surveillance scheme, were investigated and compared with trends in the incidence of occupational contact dermatitis attributed to agents other than the aforementioned metals. A sensitivity analysis restricting the study cohort to cases attributed to only one type of metal was also conducted. RESULTS: Of all cases reported to EPIDERM during the study period, 2374 (12%) were attributed to nickel, chromium or cobalt. Cases predominantly comprised females (59%), with a mean (SD) age (males and females) of 38 (13) years. Cases were most frequently reported in manufacturing, construction, and human health and social activity industries. The most frequently reported occupations were hairdressing, and sales and retail (assistants, cashiers and checkout operators). The highest annual incidence rate of contact dermatitis was observed in females (2.60 per 100 000 persons employed per year), with the first and second peak seen in those aged 16-24 and ≥ 65 years, respectively. A statistically significant decrease in the incidence of occupational contact dermatitis attributed to metals over the study period was observed for all occupations (annual average change -6.9%, 95% confidence interval -7.8 to -5.9), with much of the decrease occurring between 1996 and 2007. Similar findings were obtained in the sensitivity analyses. CONCLUSIONS: Over a period of 24 years, there has been a statistically significant decline in the incidence of metal-related occupational contact dermatitis in the UK. This could be attributed not only to improvements in working conditions, which have reduced metal exposure, but could also be due to the closure of industries in the UK that might have generated cases of contact dermatitis owing to metal exposure.

Impact of atopic dermatitis on occupational contact dermatitis among young people: A retrospective cohort study.

BACKGROUND: Occupational contact dermatitis (OCD) is a common occupational disease. Atopic dermatitis (AD) is a known risk factor for OCD. OBJECTIVES: To determine the prevalence of previously diagnosed AD among young workers with recognized OCD and assess its impact on OCD prognosis. METHODS: A retrospective cohort study. A questionnaire was sent to 6251 workers with recognized OCD who were under 35 years at notification (response rate: 47%). Of the respondents, 2392 answered a question about previous doctor-diagnosed AD and were included in the study. Eczema severity, occupational consequences and quality of life were examined using statistical analyses comparing workers with and without previously diagnosed AD. RESULTS: The prevalence of previously diagnosed AD was 41.8% (95% CI: 39.8-43.8). Women had a higher AD prevalence, and workers with AD reported OCD at a younger age. Workers with AD reported more frequent and severe eczema symptoms and had a higher risk of OCD negatively affecting job and occupation choices. Health-related quality of life was more adversely affected in workers with AD. CONCLUSIONS: AD significantly impacts severity and has long-term consequences for young people with OCD. Targeted prevention strategies need to be developed.

More than just methylisothiazolinone: Retrospective analysis of patients with isothiazolinone allergy in North America, 2017-2020.

BACKGROUND: Isothiazolinones are a common cause of allergic contact dermatitis. OBJECTIVE: To examine the prevalence of positive patch test reactions to isothiazolinones from 2017-2020 and characterize isothiazolinone-allergic (Is+) patients compared with isothiazolinone nonallergic (Is-) patients. METHODS: Retrospective cross-sectional analysis of 9028 patients patch tested to methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI) 0.02% aqueous, MI 0.2% aqueous, benzisothiazolinone (BIT) 0.1% petrolatum, and/or octylisothiazolinone (OIT) 0.025% petrolatum. Prevalence, reaction strength, concurrent reactions, clinical relevance, and source of allergens were tabulated. RESULTS: In total, 21.9% (1976/9028) of patients had a positive reaction to 1 or more isothiazolinones. Positivity to MI was 14.4% (1296/9012), MCI/MI was 10.0% (903/9017), BIT was 8.6% (777/9018), and OIT was 05% (49/9028). Compared with Is-, Is+ patients were more likely to have occupational skin disease (16.5% vs 10.3%, P <.001), primary hand dermatitis (30.2% vs 19.7%, P <.001), and be >40 years (73.1% vs 61.9%, P <.001). Positive patch test reactions to >1 isothiazolinone occurred in 44.1% (871/1976) of Is+ patients. Testing solely to MCI/MI would miss 47.3% (611/1292) of MI and 60.1% (466/776) of BIT allergic reactions. LIMITATIONS: Retrospective cross-sectional study design and lack of follow-up data. CONCLUSION: Sensitization to isothiazolinones is high and concurrent sensitization to multiple isothiazolinone allergens is common.

Results of patch testing 2-hydroxyethyl methacrylate (HEMA) in the European baseline series: A 4-year retrospective study.

BACKGROUND: 2-Hydroxyethyl methacrylate (HEMA) was added to the European baseline series (EBS) in 2019. Few recent data are available on the frequency and relevance of positive reactions to this hapten. OBJECTIVES: To investigate the frequency and relevance of positive patch tests to HEMA in the EBS in a university hospital in Amsterdam, The Netherlands. PATIENTS AND METHODS: Retrospective study in patients with positive patch tests to HEMA investigated between June 2019 and August 2023. RESULTS: Of 2927 consecutive patients, 88 (79 women and 9 men; 3.0%) had a positive reaction to HEMA. The prevalence in women was 3.9%, in men 1.0%. Forty-three (49%) reactions were judged to be of current clinical relevance and 21 (24%) of past relevance. In this group of 64 patients with relevant reactions, 18 (28%) had occupational contact with (meth)acrylate-containing products, of who 11 (61%) were nail stylists. In 46 patients with non-occupational allergic contact dermatitis, 31 (67%) had allergic reactions to nail cosmetics. Glues and glue-containing products accounted for 22% of the materials causing allergic contact dermatitis and dental products for 8%. CONCLUSIONS: Allergic reactions to HEMA are very frequent in women investigated in Amsterdam. Nearly two thirds of cases were caused by nail cosmetics.

Hand eczema in Danish adolescents-Beyond atopic dermatitis.

BACKGROUND: Hand eczema (HE) is a common inflammatory skin disease that may have serious consequences. The age of HE onset varies, but is estimated to be early- to mid-20s. However, very little is known about HE in childhood and adolescence. OBJECTIVE: We aimed to explore the epidemiology, aetiology and severity of HE among a random sample of Danish adolescents drawn from the general population. METHODS: The study was designed as a self-administered questionnaire study. An electronic questionnaire was sent to a random sample of 13 000 individuals aged 15-19 years. RESULTS: The point-prevalence, 1-year prevalence and life-time prevalence of HE among Danish adolescents was 4.9%, 12.1% and 18.3%, respectively. Among patients with a history of HE, 64.6% of cases were not associated with atopic dermatitis. Of all respondents, 60.2% were either part-time or full-time employed. Among respondents with current HE, 38.2% believed that the occupational exposures either caused or exacerbated the HE. CONCLUSION: We found a high prevalence of HE among Danish adolescents which raises concern. Knowing the potential consequences that HE may have, attention should be paid to the prevention of HE in adolescence, especially on occupational aspects and prevention of skin disease in young workers.

Occupational exposure to epoxy components and risk of dermatitis: A registry-based follow-up study of the wind turbine industry.

BACKGROUND: Allergic contact allergy and dermatitis are frequently reported among epoxy-exposed workers. OBJECTIVES: To determine the risk of dermatitis associated with epoxy exposure. METHODS: We followed 825 epoxy-exposed and 1091 non-exposed blue-collar workers, and 493 white-collar workers of a Danish wind turbine blade factory during 2017-2022 with linked data from national health registers on diagnoses, patch testing, or fillings of prescriptions for topical corticosteroids. Incidence rate ratios of dermatitis or a first-time topical corticosteroid prescription were estimated with Poisson regression using non-exposed blue-collar workers as reference. We similarly estimated incidence rate ratios for the duration of epoxy exposure and current epoxy exposure. RESULTS: Epoxy-exposed blue-collar workers showed a dermatitis incidence rate of 2.1 per 100 000 person days, a two-fold increased risk of dermatitis and a 20% increased risk of filling a prescription for topical corticosteroids. Incidence rate ratios were higher during early exposure and declined with further exposure for both outcomes. White-collar workers had generally lower risks. CONCLUSION: We observed an increased risk of dermatitis following epoxy exposure confirming previous case reports and cross-sectional studies emphasizing the need for intensified focus on preventive efforts for this group of workers.

Frequency and clinical relevance of contact allergy in dental patients.

BACKGROUND: While many studies have reported on occupational allergic contact dermatitis amongst dental personnel, studies on the relevance of patch testing in dental patients are scarce. OBJECTIVES: To determine the frequency and clinical relevance of contact allergy in patients with intra- and perioral complaints. METHODS: A total of 360 patients with intra- and perioral complaints suspected of having a contact allergy were patch-tested with the dental allergen series, European Baseline Series, and extended Amsterdam Baseline Series at Amsterdam University Medical Centers between January 2015 and November 2021. RESULTS: A total of 285 patients (79.2%) had a positive patch test reaction for either one (18.6%) or multiple allergens (60.6%). Sodium tetrachloropalladate was the most sensitising allergen with 98 patients (27.2%) testing positive, followed by nickel sulphate (23.3%), methylisothiazolinone (15.6%), and fragrance mix I (14.2%). Clinical relevance was found in 68 of 208 patients (32.7%), with patients having one (15.4%) or multiple (17.3%) patch test reactions clinically relevant to their (peri)oral complaints. CONCLUSIONS: Clinically relevant patch test reactions were frequently seen in dental patients. Although this study provides us with a better understanding on the frequency and clinical relevance of contact allergy in dental patients, further studies are needed to confirm our results.

Increased Rates of Gold and Acrylate Allergy in Individuals with Fibromyalgia Tested with an Extended Dental Patch Test Series.

Fibromyalgia is a common chronic pain condition. Rates of contact allergy in individuals with fibromyalgia have not been widely studied. Systemic contact allergy can present with muscle and joint pain and general malaise. The aim of this study is to investigate contact allergy rates in individuals with fibromyalgia to the sensitizers in an extended dental series and compare with control groups. Contact allergy to gold was significantly more common in the fibromyalgia group than the dermatitis control group. When corrected for patch test system, contact allergy to gold was significantly more common in the fibromyalgia group than the dental control group. Contact allergy to hydroxyethyl methacrylate and grouped acrylates and methacrylates was significantly more common in the fibromyalgia group than the dental control group. In conclusion, individuals with fibromyalgia may have a propensity to sensitization to gold, either via an increased exposure or an alteration in the oral environment. Gold is also implicated in systemic contact dermatitis and may be a factor in elicitation of symptoms in individuals with fibromyalgia. Acrylate allergy is also common in the fibromyalgia population and may be a consequence of occupational exposure or dental treatment.

The prevalence of contact dermatitis among surgical assistants, anaesthesia assistants and anaesthesiologists working at the Amsterdam University Medical Centre.

BACKGROUND: Professions requiring frequent and/or long lasting wet-work are at high risk for contact dermatitis (CD). CD may lead to loss of work productivity, sick leave and reduced quality of work. The 1-year prevalence of healthcare workers varies between 12% and 65%. However, the prevalence of CD among surgical assistants, anaesthesia assistants and anaesthesiologists is unknown. OBJECTIVES: (1) To establish the point-prevalence and 1-year prevalence among surgical assistants, anaesthesia assistants and anaesthesiologists and (2) to determine the impact of CD on work and daily activities. METHOD: A single-centre cross-sectional prevalence study was conducted among surgical assistants, anaesthesia assistants and anaesthesiologists. Data were obtained from the Amsterdam University Medical Centre between the 1 June 2022 and 20 July 2022. For data collection, a questionnaire was used, derived from the Dutch Association for Occupational Medicine (NVAB). Participants with an atopic predisposition or symptoms of CD were invited to the contact dermatitis consultation hour (CDCH). RESULTS: A total of 269 employees were included. The total point prevalence of CD was 7.8%; 95% CI: 4.9-11.7, the total 1-year prevalence was 28.3%; 95% CI: 23.0-34.0. The point-prevalence among surgical assistants, anaesthesia assistants and anaesthesiologists was 14%, 4% and 2%, respectively. The 1-year prevalence was 49%, 19% and 3%, respectively. Two employees reported changed work-tasks because of symptoms, no sick days were reported. The majority of the visitors of the CDCH indicated an impact on work productivity and daily activities because of CD; however, the extent to which varied widely. CONCLUSION: This study established that CD is a relevant occupational health disease among surgical assistants, anaesthesia assistants and anaesthesiologists.

Patch Testing to Chlorhexidine Digluconate, 1% Aqueous: North American Contact Dermatitis Group Experience, 2015-2020.

Background: Chlorhexidine is an antiseptic that may cause allergic contact dermatitis. Objectives: To describe the epidemiology of chlorhexidine allergy and characterize positive patch test reactions. Methods: This retrospective study analyzed patients patch tested to chlorhexidine digluconate 1% aqueous by the North American Contact Dermatitis Group, 2015-2020. Results: Of 14,731 patients tested to chlorhexidine digluconate, 107 (0.7%) had an allergic reaction; of these, 56 (52.3%) reactions were currently clinically relevant. Most (59%) reactions were mild (+), followed by strong (++, 18.7%) and very strong (+++, 6.5%). Common primary dermatitis anatomic sites in chlorhexidine-positive patients were hands (26.4%), face (24.5%), and scattered/generalized distribution (17.9%). Compared with negative patients, chlorhexidine-positive patients were significantly more likely to have dermatitis involving the trunk (11.3% vs 5.1%; P = 0.0036). The most commonly identified source category was skin/health care products (n = 41, 38.3%). Only 11 (10.3%) chlorhexidine reactions were occupationally related; of these, 81.8% were in health care workers. Conclusions: Chlorhexidine digluconate allergy is uncommon, but often clinically relevant. Involvement of the hands, face, and scattered generalized patterns was frequent. Occupationally related reactions were found predominantly in health care workers.

Contact allergy to ingredients of hair cosmetics in female hairdressers and female consumers-An update based on IVDK data 2013-2020.

BACKGROUND: Hair cosmetic products contain several, partly potent contact allergens, including excipients like preservatives. Hand dermatitis in hairdressers is common, scalp and face dermatitis in clients or self-users (summarised here as 'consumers') may be severe. OBJECTIVE: To compare frequencies of sensitization to hair cosmetic ingredients and other selected allergens between female patch tested patients working as hairdressers and consumers without professional background, respectively, who were tested for suspected allergic contact dermatitis to such products. METHODS: Patch test and clinical data collected by the IVDK (https://www.ivdk.org) between 01/2013 and 12/2020 were descriptively analysed, focusing on age-adjusted sensitization prevalences in the two subgroups. RESULTS: Amongst the 920 hairdressers (median age: 28 years, 84% hand dermatitis) and 2321 consumers (median age: 49 years, 71.8% head/face dermatitis), sensitization to p-phenylenediamine (age-standardised prevalence: 19.7% and 31.6%, respectively) and toluene-2,5-diamine (20 and 30.8%) were most common. Contact allergy to other oxidative hair dye ingredients was also more commonly diagnosed in consumers, whereas ammonium persulphate (14.4% vs. 2.3%) and glyceryl thioglycolate (3.9 vs. 1.2%) as well as most notably methylisothiazolinone (10.5% vs. 3.1%) were more frequent allergens in hairdressers. CONCLUSIONS: Hair dyes were the most frequent sensitizers both in hairdressers and in consumers; however, as indication for patch testing may differ, prevalences cannot directly be compared. The importance of hair dye allergy is evident, often with marked coupled reactivity. Workplace and product safety need to be further improved.

Dermato-allergological risks in beauty operators.

Beauticians, hairdressers, and barbers are among the occupations with the highest rates of work-related skin diseases, especially occupational contact dermatitis (OCD). Irritant contact dermatitis (ICD) due to chronic mild trauma (frictional dermatitis), contact with soaps, detergents, and wet work is frequent in beauty operators. Para-phenylenediamine (PPD), acrylates, essential oils, fragrances, colophony, and preservatives are most frequently responsible for allergic contact dermatitis (ACD) in these professional categories. Young women are mainly affected, with the most affected sites being the hands. Anamnesis, patch tests with the baseline, integrative series, and use products are important to understand possible sensitization. To reduce the risk, prevention is important, and workers should be adequately trained in the use of personal protective equipment (PPE).

Methyl(chloro)isothiazolinone contact allergy: a monocentric experience from Turkey.

INTRODUCTION: Due to their ubiquitous use, isothiazolinones caused allergic contact dermatitis epidemics and their use was restricted by legal regulations. OBJECTIVES: We aimed to evaluate demographic data, clinical findings, and patch test features of patients with methylisothiazolinone (MI) and/or methylchloroisothiazolinone(MCI) sensitivity in our study. METHODS: This study is a bidirectional and cross-sectional study, between July 2020 and September 2021. A total of 616 patients, including prospective and retrospective populations, demographic data, clinical findings, and patch test results were reviewed. Patients' demographics, patch test results, allergen sources, presence of occupational contact, and the characteristics of dermatitis attacks were recorded. RESULTS: A total of 50 patients with MI and MCI/MI sensitivity, 36 male (72%) and 14 female (28%), were included in our study. The overall prevalence of MI and MCI/MI between 2014 and 2021 was 8.4% (52/616) with two peak levels in 2015(21%) and 2021 (20%). A statistically significant relationship was found between shampoo use and facial involvement (p = 0.031), shower gel use and arm involvement (p = 0.027), wet wipe use and hand involvement (p = 0.049), detergent use and the pulps (p = 0.026) and the lateral aspects of fingers involvement (p = 0.048), water-based dye use and periungual involvement (p = 0.047). CONCLUSION: Although legal regulations related to MI and MCI/MI cause a decrease in the frequency of their sensitivities were still common causes of allergic contact dermatitis.