The association between hand eczema and nickel allergy has weakened among young women in the general population following the Danish nickel regulation: results from two cross‐sectional studies

Background: An association between nickel contact allergy and hand eczema has previously been demonstrated. In 1990, Denmark regulated the extent of nickel release in the ear‐piercing process as well as nickel release from consumer products. Objectives: This study aimed to evaluate the effect of the Danish nickel regulation by comparing the prevalence of concomitant nickel allergy and hand eczema observed in two repeated cross‐sectional studies performed in the same general population in Copenhagen. Materials: In 1990 and 2006, 3881 18–69 year olds completed a postal questionnaire and were patch tested with nickel. Data were analysed by logistic regression analyses and associations were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). Results: The prevalence of concomitant nickel contact allergy and a history of hand eczema decreased among 18–35‐year‐old women from 9.0% in 1990 to 2.1% in 2006 (P < 0.01). The association between nickel contact allergy and a history of hand eczema decreased in this age group between 1990 (OR = 3.63; CI = 1.33–9.96) and 2006 (OR = 0.65; CI = 0.29–1.46). Among older women, no significant changes were observed in the association between nickel contact allergy and hand eczema. Conclusions: Regulatory control of nickel exposure may have reduced the effect of nickel on hand eczema in the young female population.     

Nickel allergy and hand eczema--a 20-year follow up

The aim of this study was to investigate the occurrence of hand eczema after 20 years in women patch tested to nickel during childhood. In 1982-1983, 960 schoolgirls were patch tested for nickel allergy; its prevalence was found to be 9%. 20 years later, the same individuals received a questionnaire regarding hand eczema and factors of importance for the development of hand eczema. 735 of 908 women (80.9%) answered the questionnaire. In total, 17.6% of respondents reported hand eczema after the age of 15 years, and the 1-year prevalence was 12.8%. There was no statistically significant difference in the occurrence of hand eczema between the groups who had previously tested positive and negative for nickel allergy. 38.3% of the respondents considered themselves to be nickel sensitive at the time they answered the questionnaire; in this group, the reported prevalence of hand eczema after age 15 was 22.5%. 31.4% of those with a history of atopic dermatitis reported hand eczema after age 15, compared with 10.6% of those without (P < 0.001). In conclusion, contact allergy to nickel in childhood did not seem to increase the prevalence of hand eczema later in life.     

Flare-up of dermatitis following patch testing is more common in polysensitized patients

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.     

Tobacco smoking and hand eczema: a population‐based study

Background Tobacco smoking has been proposed to promote hand eczema. Objectives To examine the association between tobacco smoking and hand eczema and to investigate a possible dose‐response relation. Methods A national environmental health survey was performed in 2007. A questionnaire was mailed to 43 905 individuals and responses were obtained from 25 851 (59%). Questions on 1‐year prevalence of hand eczema and on previous and current smoking were included. Respondents were asked to report number of cigarettes per day and to provide information on history of atopy and frequency of hand exposure to water. Results In total, answers regarding smoking and hand eczema were obtained from 25 428 individuals. Of regular daily smokers, 10·0% reported hand eczema vs. 9·1% of nonsmokers (P = 0·0951). A history of atopy showed the strongest influence on the occurrence of hand eczema: prevalence proportion ratio (PPR) 3·46. The PPR for hand eczema among individuals smoking > 15 cigarettes per day was 1·25 and 1·40 in uni‐ and multivariate analysis, respectively. Age, history of atopy, sex and water exposure were found to be confounders but not effect modifiers. A dose‐response relation between level of smoking and 1‐year prevalence of hand eczema was revealed with a PPR of 1·05 (P < 0·001) for the continuous variable of smoking habits, indicating a significantly increased prevalence of hand eczema among individuals with higher consumption of tobacco. Conclusions An association between heavy smoking and hand eczema was confirmed. It is important to consider the level of exposure, as a dose‐response relation was revealed, and to be aware of confounding factors.     

Filaggrin null mutations increase the risk and persistence of hand eczema in subjects with atopic dermatitis: results from a general population study

Summary Background Hand eczema is prevalent in the general population. It remains unclear whether or not filaggrin gene (FLG) null mutations increase the overall risk of hand eczema or only increase the risk of hand eczema in subjects with atopic dermatitis. Objectives To investigate the association between FLG null mutations and hand eczema. Methods A random sample of 3335 adults from the general population in Denmark was patch tested, FLG genotyped for R501X and 2282del4 null mutations and questioned about hand eczema. Results Participants with combined presence of atopic dermatitis and FLG null mutation status had a significantly higher prevalence of hand eczema, an earlier onset of hand eczema and a higher persistence of hand eczema compared with subjects with normal FLG status and absence of atopic dermatitis. Logistic regression analyses revealed positive associations between hand eczema within the past 12 months and FLG null mutation status in participants with a history of atopic dermatitis [odds ratio (OR) 2·98; 95% confidence interval (CI) 1·27–7·01], but not in subjects without atopic dermatitis (OR 0·82; 95% CI 0·41–1·67). Conclusions FLG null mutations were significantly associated with hand eczema (< 12 months) in subjects with atopic dermatitis. Combined atopic dermatitis and filaggrin null mutation status was strongly associated with early onset of hand eczema and hand eczema persistence.     

Lack of evidence for a protective effect of prolonged breastfeeding on childhood eczema: lessons from the International Study of Asthma and Allergies in Childhood (ISAAC) Phase Two

Summary Background Exclusive breastfeeding for at least 4 months is recommended by many governments and allergy organizations to prevent allergic disease. Objectives To investigate whether exclusive breastfeeding protects against childhood eczema. Methods Study subjects comprised 51 119 randomly selected 8‐ to 12‐year‐old schoolchildren in 21 countries. Information on eczema and breastfeeding was gathered by parental questionnaire. Children were also examined for flexural eczema and underwent skin prick testing. Odds ratios (ORs) were calculated for each study centre and then pooled across populations. Results There was a small increase in the risk of reported ‘eczema ever’ in association with ‘breastfeeding ever’ and breastfeeding < 6 months [pooled adjusted OR 1·11, 95% confidence interval (CI) 1·00–1·22 and OR 1·10, 95% CI 1·02–1·20, respectively]. There was no significant association between reported ‘eczema ever’ and breastfeeding > 6 months (pooled adjusted OR 1·09, 95% CI 0·94–1·26). Risk estimates were very similar for exclusive breastfeeding < 2 months, 2–4 months and > 4 months and for eczema symptoms in the past 12 months and eczema on skin examination. As for more severe eczema, breastfeeding per se conveyed a risk reduction on sleep disturbed eczema (pooled adjusted OR 0·71, 95% CI 0·53–0·96), but this effect was lost where children had been exclusively breastfed for > 4 months (pooled adjusted OR 1·02, 95% CI 0·67–1·54). Allergic sensitization and a history of maternal allergic disease did not modify any of these findings. Conclusions Although there was a protective effect of ever having been breastfed on more severe disease, we found no evidence that exclusive breastfeeding for 4 months or longer protects against eczema. Our results are consistent with findings from a recent systematic review of prospective studies. The U.K. breastfeeding guidelines with regard to eczema should be reviewed. Intervention studies are now required to explore how and when solids should be introduced alongside breastfeeding to aid protection against eczema and other allergic diseases.     

The effect of tobacco smoking and alcohol consumption on the prevalence of self‐reported hand eczema: a cross‐sectional population‐based study

Summary Background Hand eczema is a prevalent disorder that leads to high health care costs as well as a decreased quality of life. Important risk factors include atopic dermatitis, contact allergy and wet work whereas the role of null mutations in the filaggrin gene complex remains to be clarified. It has been debated whether life‐style factors such as tobacco smoking and alcohol consumption are associated with hand eczema. Objectives The current study aimed to investigate whether self‐reported hand eczema was associated with smoking and alcohol consumption in the general population. Methods Between June 2006 and May 2008, a cross‐sectional study was performed in the general population in Copenhagen, the capital of Denmark. A random sample of 7931 subjects aged 18–69 years old was invited to participate in a general health examination including a questionnaire; 3471 (44%) participated. Data were analysed with logistic regression analyses and associations were expressed as odds ratios (ORs) with 95% confidence intervals (CI). Results The prevalence of hand eczema was higher among previous smokers (OR = 1·13; CI = 0·90–1·40), current light smokers (OR = 1·51; CI = 1·14–2·02) and current heavy smokers (OR = 1·38; CI = 0·99–1·92) compared with never‐smokers. Conclusions Tobacco smoking was positively associated with hand eczema among adults from the general population in Denmark. Apparently, current light smokers (< 15 g daily) had a higher prevalence of hand eczema than current heavy smokers (> 15 g daily) but this needs to be reconfirmed. Alcohol consumption was not associated with hand eczema.     

Filaggrin null mutations and association with contact allergy and allergic contact dermatitis: results from a tertiary dermatology clinic

Background: Filaggrin null (FLG) mutations lead to skin barrier disruption with a reduced resistance towards exogenous agents and also influence the course of disease in atopic dermatitis.
Objectives: To examine the association between FLG mutations and contact allergy, polysensitization, hand eczema at first appearance of disease, occurrence, and course of dermatitis.
Methods: A venous blood sample from 430 individuals was genotyped for FLG mutations R501X and 2282del4 with polymerase chain reaction followed by typing through hybridization to paramagnetic polystyrene beads and analysis on a BioPlex 200. All individuals had a minimum of one positive patch test reaction.
Results: In all, 3.5% were 2282del4 heterozygote and 5.1% were R501X heterozygote. An odds ratio (OR) of 1.49 [95% confidence interval (CI) 0.74–3.00] was found for nickel allergy, OR 0.84 (95% CI 0.41–1.74) for polysensitization, OR 0.78 (95% CI 0.25–2.43) for dermatitis, OR 0.96 (95% CI 0.48–1.92) for hand eczema at debut, OR 1.25 (95% CI 0.99–1.57) for duration of disease, and OR 0.76 (95% CI 0.59–0.97) for age at onset.
Conclusions: No association between nickel allergy, polysensitization, hand eczema at first appearance or occurrence of dermatitis, and FLG mutations was found. However, patients with FLG mutations had an earlier age of onset compared with the wild‐type genotype and a trend towards longer duration of disease.     

Allergic contact dermatitis in children: should pattern of dermatitis determine referral? A retrospective study of 500 children tested between 1995 and 2004 in one U.K. centre

Background Allergic contact dermatitis (ACD) increases with age, and a prevalence of between 13·3% and 24·5% has been reported. Patch testing infants may be particularly difficult, and false‐positive reactions may occur. Objectives The purpose of this retrospective study was to determine whether the site of primary dermatitis in children could predict a diagnosis of ACD. The current frequency of sensitization in children was also evaluated and the main sensitizing substances among children were verified. Methods Between 1995 and 2004, 500 children were patch tested and entered on to the patch test database at Leeds General Infirmary. Analysis of the database included identifying the presenting patterns of eczema and reviewing the patch test results for each child. Results Of the children, 133 (27%) had one or more positive patch test result. The effect of age on the likelihood of a positive patch test was highly significant (P < 0·001). Girls were significantly more likely to have a positive patch test compared with boys: odds ratio for a positive test 0·62 (95% confidence interval 0·41–0·95; P = 0·029). Type IV allergy to nickel (33%) was the most frequent finding. Reactions to fragrance mix (18%), cobalt (11%), mercapto chemicals, Myroxylon pereirae and p‐phenylenediamine (each 8%) were the next most common. No statistical significance was found in the relationship between the site of primary dermatosis and a positive patch test result. Conclusions The pattern of presenting dermatitis in children should not determine referral for patch testing. Any child with persistent eczema should be referred for patch testing.     

Prognosis in nickel allergy and hand eczema

63 female patients with nickel allergy and hand eczema were reinvestigated 6 years after the primary investigation. 30% of the patients were healed. Patients with the pompholyx-type eczema had the worst prognosis. The start of hand eczema was not correlated to any particular occupation. There was a strong correlation between a history of metal sensitivity and a positive patch test reaction. High frequencies of personal and family atopy were found, and atopy made the prognosis worse. Determination of serum IgE was not found to be of any use in predicting the prognosis in patients with nickel allergy and hand eczema.     

Filaggrin loss-of-function mutation R501X and 2282del4 carrier status is associated with fissured skin on the hands: results from a cross-sectional population study

Background Filaggrin metabolites act as osmolytes and are important for skin hydration. Carriers of filaggrin loss‐of‐function mutations have a higher prevalence of atopic dermatitis and dry skin. There is also evidence to suggest that filaggrin mutations increase the risk of hand eczema in atopic individuals. In our clinic, we have observed a distinct phenotype of hand eczema in patients with filaggrin mutation carrier status, characterized by fissured dermatitis on the dorsal aspect of the hands and with only sparse involvement of the palms including fine scaling. Objectives To investigate whether filaggrin loss‐of‐function mutations are associated with skin fissures on the hands and/or fingers in the general population. Methods Participants in a population‐based study were questioned about skin symptoms, genotyped for filaggrin mutation, patch tested for nickel allergy and skin prick tested. Results In an adjusted logistic regression analysis, filaggrin mutation status was significantly associated with fissured skin on the hands and/or fingers in adults (odds ratio 1·93, 95% confidence interval 1·05–3·55) and showed a nearly significant negative interaction with atopic dermatitis (P = 0·055), suggesting that the effect was predominantly in subjects without atopic dermatitis. Conclusions Filaggrin loss‐of‐function mutations seem not only to increase the risk of atopic dermatitis and dry skin but also the risk of fissures on the hands and/or fingers in subjects without atopic dermatitis. Prophylactic emollient therapy should be particularly encouraged in filaggrin loss‐of‐function mutation carriers.     

Self-diagnosed dermatitis in adults. Results from a population survey in Stockholm

In a population-based survey of public health issues in Stockholm, Sweden, self-reported hand eczema, history of childhood eczema, nickel allergy, occurrence of skin symptoms on the face and intolerance to cosmetics and hygiene products, were investigated. A postal questionnaire was sent to 15,000 inhabitants aged 19-80 years. The response rate was 73%. The 1-year prevalence of hand eczema was 8% (females 10%, males 6%). History of childhood eczema was reported by 15% and, of these, 42% also stated positively that they had had hand eczema at some time. Hypersensitivity to nickel was owned to 15% of the females and 3% of the males. Of the nickel-sensitive, 30% reported ever having had hand eczema. The combination of nickel allergy and history of childhood eczema resulted in a cumulative prevalence of hand eczema of 56%. Females reported more hand-washings per day than did males, and a relation between number of hand-washings and hand eczema was found. Self-reported 1-year prevalence of skin symptoms on the face was 14% and, of these, 33% also owned to hypersensitivity to cosmetics. Dermatitis appears to be a common health problem. This fact should be made clear to those who give priority and allocate resources to health problems, e.g., by participation of dermatologists in performing population-based surveys.     

The association between contact allergy and hand eczema in 2 cross-sectional surveys 8 years apart

Hand eczema is a recurrent chronic skin disease related to contact allergy and atopic dermatitis. When possible, efforts should be redoubled to eliminate provoking factors. Our objective was to assess changes in the prevalence of self-reported hand eczema and to evaluate the association between contact allergy and hand eczema among adult Danes before and after nickel exposure regulation in Denmark. In 1990 and 1998, random samples of 15-41-year-old persons were examined in 2 cross-sectional studies of the general population in Copenhagen, Denmark. The studies included questionnaires, patch and prick testing. From 1990 to 1998 the prevalence of a history of hand eczema increased significantly. This increase did not appear to be fully explained by changes in the prevalence of flexural eczema, prick test reactivity, patch test reactivity, and nickel allergy. In 1990, nickel allergy and allergic nickel contact dermatitis were significantly associated with a history of hand eczema among women. In 1998, these associations were not found. It can be concluded that, from 1990 to 1998, the prevalence of a history of hand eczema rose significantly. It was indicated that it might be possible to prevent the hand eczema related to nickel allergy by exposure regulation, public education or both.     

Nickel,cobalt and chromate sensitization and occupation*

Background: Exposure to nickel, cobalt and chromate are important causes of occupational contact dermatitis. Objectives: To estimate the prevalence of nickel, cobalt and chromate allergy in a population of consecutive patients and to investigate the possible association with individual and occupational risk factors. Patients/Methods: A total of 14 464 patients (67.6% women and 32.4% men) with suspected allergic dermatitis underwent patch tests. The associations between patch test results and occupations were studied by multivariate logistic regression analysis. Results: About 24.6% of the patients reacted positively to nickel sulphate, 10.2% to cobalt chloride and 8.7% to potassium dichromate. Nickel sensitization was higher in women aged 26–35 years in comparison with the youngest group (15–25 years) and the older group (> 45 years). In women, the prevalence of positive reactions to nickel was positively associated with metal and mechanical work (OR 1.54; 95%, CI 1.16–2.05). Chromate sensitization was more prevalent in building trade workers for both women (OR 1.58; 95% CI 1.00–2.49) and men (OR 2.24; 95% CI 1.55–3.22). Cobalt sensitization was associated with textile and leather work in women (OR 1.52; 95% CI 1.09–2.12) and with cleaning work in men (OR 1.86; 95% CI 1.18–2.93). Conclusions: Our study showed interesting associations between some occupations and nickel, chromate and cobalt allergy.     

Cobalt allergy in hard metal workers

Hard metal contains about 10% cobalt. 853 hard metal workers were examined and patch tested with substances from their environment. Initial patch tests with 1% cobalt chloride showed 62 positive reactions. By means of secondary serial dilution tests, allergic reactions to cobalt were reproduced in 9 men and 30 women. Weak reactions could not normally be reproduced. A history of hand eczema was found in 36 of the 39 individuals with reproducible positive test reactions to cobalt, while 21 of 23 with a positive initial patch test but negative serial dilution test had never had any skin problems. Hand etching and hand grinding, mainly female activities and traumatic to the hands, were found to involve the greatest risk of cobalt sensitization. 24 individuals had an isolated cobalt allergy. They had probably been sensitized by hard metal work, while the individuals, all women, who had simultaneous nickel allergy had probably been sensitized to nickel before their employment and then became sensitized to cobalt by hard metal work. A traumatic occupation, which causes irritant contact dermatitis and/or a previous contact allergy or atopy is probably a prerequisite for the development of cobalt allergy.     

FS02.6Patch test reactivity to nickel sulphate and fragrance mix in unselected children

Aim:  To investigate the occurrence of hand eczema after 20 years in schoolgirls previously patch‐tested to nickel.
Methods:  In 1982–83, 960 schoolgirls, aged 8, 11 and 15 years, were investigated for the occurrence of nickel allergy (Larson‐Stymne B and Widström L, Contact Dermatitis 1985:13:289–293). The girls were patch‐tested and the prevalence of nickel allergy was 9%. Twenty years later, the same individuals have received a questionnaire regarding hand eczema and factors of importance for the development of hand eczema. After two reminders, the response rate was 81%.
Results:  In total 17.5% of the girls reported hand eczema after the age of 15. The 1‐year prevalence of hand eczema was 12.6%. Of the previously patch‐tested schoolgirls who answered the questionnaire, 63 were sensitive to nickel. In this study, the prevalence of hand eczema among those 63 was 16%, compared to 17% in the non‐sensitive group (NS). Excluding persons with atopic dermatitis, the prevalence of hand eczema was 12.5% in the nickel‐sensitive group, and 10% among the others (NS). 32% of the persons who had had atopic dermatitis reported hand eczema after 15 years of age, compared to 10% of those with no history of atopic dermatitis (p < 0.001).
Conclusion:  Contact allergy to nickel in early childhood (8–15 years) did not seem to increase the prevalence of hand eczema later in life. The prevalence of hand eczema was increased by a factor of three among those with a history of atopic dermatitis, which is in accordance with earlier reports.     

Nickel allergy from adolescence to adulthood in the TOACS cohort

Background In 1995, we established a cohort of 1501 unselected eighth‐grade schoolchildren to investigate the course of nickel allergy into adult life. Objectives To follow the course of nickel allergy and clinically relevant nickel dermatitis over 15 years from adolescence to adulthood, and the effect of ear piercing, atopic dermatitis and degree of nickel patch test reactivity. Methods One thousand two hundred and six young adults from the cohort were asked to complete a questionnaire and participate in a clinical examination including patch testing with TRUE Test® including a nickel dilution series. Results The questionnaire was answered by 899 (74.6%), and 442 (36.7%) had patch tests performed. The point prevalence of nickel allergy was 11.8% (clinical relevance 80.8%). The 15‐year incidence rate was 6.7%. Most new sensitizations were clinically relevant with strong reactions, and many participants reacted to low concentrations. Only a few positive reactions were lost. Nickel allergy was more common among women with childhood atopic dermatitis, whereas no association with ear piercing was found. However, there was a significantly higher prevalence of nickel allergy among women ear pierced before implementation of the nickel regulation in Denmark. Conclusion This follow‐up study in young adults 15 years after leaving primary school showed a high prevalence and a high incidence rate of nickel allergy, despite the nickel regulation. Most reactions from childhood could be reproduced and were clinically relevant. In women, childhood atopic dermatitis was associated with nickel allergy in adulthood, whereas only ear piercing before the Danish nickel regulation was associated with adult nickel allergy.     

Contact allergy to allergens of the TRUE-test (panels 1 and 2) has decreased modestly in the general population

Summary Background The prevalence of contact allergy in the general population is nearly 20%. Objectives This study aimed to monitor the development of contact allergy to allergens from the TRUE‐test (panels 1 and 2) between 1990 and 2006. Methods Two random samples of adults from the general population in Copenhagen, Denmark, were invited to participate in a general health examination including patch testing. In 1990 and 2006, we patch tested and questioned 543 and 3460 adult Danes. Patch test readings were performed on day 2 only. Results The overall prevalence decreased significantly from 15·5% in 1990 to 10·0% in 2006, mainly as a result of a decrease in thimerosal allergy from 3·4% to 0·8%. Furthermore, the prevalence of cobalt allergy and rubber‐related allergens decreased from 1·1% to 0·2% and from 1·5% to 0·2%, respectively. Stratification by sex and age group revealed decreasing prevalences of contact allergy in all male age groups and in young and middle‐aged female age groups (18–55 years) whereas increasing prevalences were observed among older women (56–69 years). The diverging trend observed in women was probably explained by a cohort effect due to a change in the prevalence of nickel allergy following the Danish regulation on nickel exposure. Conclusions Although the overall prevalence of contact allergy decreased in the general population, frequent contact allergens such as fragrance mix II and methyldibromo glutaronitrile were not tested. Thus, contact allergy remains prevalent in the general population.     

The association between null mutations in the filaggrin gene and contact sensitization to nickel and other chemicals in the general population

Background It was recently shown that filaggrin gene (FLG) null mutations are positively associated with nickel sensitization. We have hypothesized that histidine‐rich filaggrin proteins in the epidermis chelate nickel ions and prevent their skin penetration and exposure to Langerhans cells. Furthermore, we have proposed that the low degree of genetic predisposition to nickel sensitization found by a Danish twin study was explained by a high prevalence of ear piercing among participants resulting in ‘bypassing’ of the filaggrin proteins. Objectives To investigate the association between FLG null mutations and (nickel) contact sensitization. Methods A random sample of 3335 adults from the general population in Denmark was patch tested and genotyped for R501X and 2282del4 in the FLG gene. Results The combined carrier frequency of FLG null mutations was 8·1%. Nickel, fragrance and contact sensitization to at least one allergen were not associated with FLG null mutations. A crude analysis on women who did not have ear piercings revealed a positive association between FLG null mutations and nickel sensitization [8·3% vs. 2·4%; odds ratio (OR) 3·71, 95% confidence interval (CI) 0·73–18·96] as well as between FLG null mutations and allergic nickel dermatitis (8·3% vs. 1·3%; OR 6·75, 95% CI 1·17–38·91). FLG mutation status and atopic dermatitis were positively associated with neomycin or ethylenediamine sensitization. Conclusions This study suggests that FLG null mutations may be a risk factor for the development of nickel sensitization. However, ear piercing was a much stronger risk factor in our general population and we could therefore identify a positive association only in women without ear piercings. Contact sensitization to specific chemicals is related to treatment exposure.     

Hand dermatitis and allergic patch test reactions caused by nickel in electroplaters

A worksite survey was conducted in all 38 Finnish electroplating plants. All workers ( n =163) who worked with nickel plating (bath workers, hangers and solution makers) were interviewed with a questionnaire about symptoms of nickel dermatitis, hand dermatitis, and about protective measures, atopy, etc. Patch testing with nickel sulfate was done with the TRUE Test^TM method. All the workers, 94 men and 69 women, answered the questionnaire. The mean age of women was 41.1 years, and of men 43.1 years, respectively. Men had longer occupational exposure to nickel (14 years) than women (10 years). Most workers used protective gloves. 35% of women and 30% of men reported present or past hand dermatosis. 19% reported a history of atopic dermatitis. 15% of women ( n = 8) and 4% ( n = 2) of men had an allergic patch test reaction to nickel sulfate. 70% of those with an allergic patch test reaction to nickel reported past or present hand eczema. The prevalence of nickel allergy among the electroplaters was similar to that of patients in patch test clinics in Finland. An allergic patch test reaction to nickel sulfate does not necessarily oblige an electroplater to change jobs.