Johannes Geier

National rates and regional differences in sensitization to allergens of the standard series-Population-adjusted frequencies of sensitization (PAFS) in 40,000 patients from a multicenter study (IVDK)

Sensitization rates to contact allergens vary between centers and are influenced by sex and age. Eliminating the latter 2 factors by standardization of data by age and sex, the present analysis address possible differences between centers remaining after elimination of these confounders, and analyzes other factors which might influence rates, e.g. the MOAHL index. Overall standardized rates were well within the range reported in previous studies and may be regarded as representing the rates of the “patch test population” in Central Europe (e.g. nickel sulfate 12.9%, fragrance mix 10.5″. balsam of Peru 7.3%. thimerosal 5.6%). For this analysis, data of those departments which contributed more than 2000 patients or of those with extreme proportion concerning sex, age and occupational cases were selected. Patients from these 10 departments differed considerably will regard to the items of the MOAHL index and with regard to standardized rates. The items of the MOAHL index proved to be suitable for describing different patch test populations and for explaining some differences between centers. Only ‘atopic dermatitis’ seems to have little influence on (standardized) rates. Face dermatitis is not yet represented in the MOAHL index, but should be included, together with age > 40 years, in an extended index (acronym: MOAHLFA). Regional allergen exposure (with striking differences between East Germany, West Germany and to a lesser extent Austria) seems to have a great influence on the sensitization pattern observed in a department. In addition, sociological factors may influence sensitization rates, which is exemplified by high rates of nickel allergy in a socially delined subgroup. Future studies should focus on these factors, as well as on factors concerning patch test practices and quality control.

Sensitization to 26 fragrances to be labelled according to current European regulation. Results of the IVDK and review of the literature.

To study the frequency of sensitization to 26 fragrances to be labelled according to current European regulation. During 4 periods of 6 months, from 1 January 2003 to 31 December 2004, 26 fragrances were patch tested additionally to the standard series in a total of 21 325 patients; the number of patients tested with each of the fragrances ranged from 1658 to 4238. Hydroxymethylpentylcyclohexene carboxaldehyde (HMPCC) was tested throughout all periods. The following frequencies of sensitization (rates in %, standardized for sex and age) were observed: tree moss (2.4%), HMPCC (2.3), oak moss (2.0), hydroxycitronellal (1.3), isoeugenol (1.1), cinnamic aldehyde (1.0), farnesol (0.9), cinnamic alcohol (0.6), citral (0.6), citronellol (0.5), geraniol (0.4), eugenol (0.4), coumarin (0.4), lilial (0.3), amyl‐cinnamic alcohol (0.3), benzyl cinnamate (0.3), benzyl alcohol (0.3), linalool (0.2), methylheptin carbonate (0.2), amyl‐cinnamic aldehyde (0.1), hexyl‐cinnamic aldehyde (0.1), limonene (0.1), benzyl salicylate (0.1), γ‐methylionon (0.1), benzyl benzoate (0.0), anisyl alcohol (0.0). 1) Substances with higher sensitization frequencies were characterized by a considerable number of ‘++/+++’ reactions. 2) Substances with low sensitization frequencies were characterized by a high number of doubtful/irritant and a low number of stronger (++/+++) reactions. 3) There are obviously fragrances among the 26 which are, with regard to contact allergy, of great, others of minor, and some of no importance at all.

Epidemiology of contact allergy: an estimation of morbidity employing the clinical epidemiology and drug-utilization research (CE-DUR) approach.

Clinical epidemiology (CE) is considered unable to estimate morbidity concerning either contact sensitization (CS) or allergic contact dermatitis (ACD) at the population level. Drug‐utilization research (DUR) methods estimate the morbidity of suitable diseases based on prescription data for disease‐specific drugs. Our objective was to estimate population figures for incidence and prevalence of ACD and CS based on sales data for patch test material in Germany and on patient data from the Information Network of Departments of Dermatology (IVDK). Approximately 600,000 standard series are sold per year in Germany, according to the 2 main manufacterers. This raw sales figure was corrected for certain effects (discarded preparations, proportion of formerly patch‐tested patients, proportion of patients with ACD seeking medical advice) to obtain an estimate of the denominator of patients eligible for patch testing annually, and combined with patch test results from the Information Network of Departments of Dermatology (IVDK). In 17.8% (of 9,266 IVDK patients) ACD was established. Extrapolated to the general population, an incidence of ACD of between 1.7 and 7 per 1000 per year was estimated, depending on whether conservative or more liberal assumptions concerning the above effects were made. Of 78,067 IVDK patients tested between 1992 and 2000, 46.8% had at least 1 positive reaction (+ to + + +), and 22.7% had at least 1 stronger positive reaction (+ + or + + +).The 9‐year prevalence of CS was estimated to lie between 4.0% and 16.6% for the first outcome, and between 2.0% and 8.1% for the second. Concerning single allergens, 1.9–4.5 million individuals are probably sensitized to nickel, and 1.4–3.4 million to fragrance mix among the German population of 82 million inhabitants. The morbidity data found in this study are in good accordance with data from population‐based epidemiological studies. In comparison to these, the CE‐DUR approach seems to be an economically feasible method to estimate continuously the population impact of ACD and CS.

Contact allergy to fragrances: frequencies of sensitization from 1996 to 2002. Results of the IVDK

Increasing frequencies of sensitization to the fragrance mix (FM) have been acknowledged as a serious problem for many years. It is well known that the single compounds (SCs) of the FM contribute differently to the FM patch rest reactions. In this study, we were interested in the time trends of the FM, the SCs, Myroxylon pereirae resin (MP; balsam of Peru) and oil of turpentine (OT) as possible further indicators of perfume allergy and analysed the data collected by the Information Network of Departments of Dermatology multicentre project from 1996 to 2002. During the study period (1996–2002), the FM [8% petrolatum (pet.)], MP (25% pet.) and OT (1% pet.) were tested in 59 298, 59 334 and 59 478 patients, respectively. SCs were tested in a selected group of patients, ranging from n = 1083 to n = 1924 per year. A significant increase in the proportions of patients with positive reactions to FM, MP and OT between 1996 and 1998 is noted, and a significant decline from 1999 to 2002 (Cochrane Armitage trend test, P < 0.0001). The highest frequency of sensitization to the FM was 13.1% in 1999, and the lowest 7.8% in 2002. The number of concomitant reactions to OT, a surrogate marker for terpenes, in FM‐positive patients was significantly increased between 1997 and 1999. Reactions to SCs in FM‐positive patients were observed in 29.9% (oak moss absolute) to 5.9% (geraniol). There was no time trend in reactions to SCs, although the relative share was increased for isoeugenol, cinnamic aldehyde and geraniol in 1999. In summary, we report for the first time, a significant decline in sensitization to the FM, very probably due to a reduced exposure (less potent allergens used in fine fragrances, possibly less use of natural ingredient‐based cosmetics and lowered use concentration of important fragrance allergens). The differences in ranking of SCs could stimulate (a) a redefinition of the FM and (b) a differentiated preventive and regulatory approach, with oak moss and isoeugenol being regulated strictly by prohibition, concentration limits further reconsidered and/or health warnings and clearly less noxious substances like geraniol treated less restrictively.

Patch testing with contact allergens

One-year prevalence of contact dermatitis in the general population is 7%. 15 to 20% of the general population are sensitized to one of the common allergens [1, 2]. Contact dermatitis is the subject of a current guideline of the German Dermatologic Society (Deutsche Derma tologische Gesellschaft, DDG) [3]. The patch test is the only instrument suitable for routine diagnostics to prove sensitization to a substance causing an allergic contact dermatitis. Synchronous reproducibility ranges from 60 to 90 %, depend ing on test method and allergen [4, 5].

Patch test results in schoolchildren. Results from the Information Network of Departments of Dermatology (IVDK) and the German Contact Dermatitis Research Group (DKG)

Our aim was to explore the current spectrum of contact allergens in schoolchildren, as a basis for diagnosis and prevention of allergic contact dermatitis. Results of patch tests in children 6–15 years old, performed in the years 1990–1995 by 22 centres of the German Contact Dermatitis Research Group and filed by the Information Network of Departments of Dermatology, were analysed and evaluated retrospectively, including epidemiologic data. Children with positive tests (62 out of 156 boys and 108 out of 260 girls tested) had a higher frequency of allergic contact dermatitis and a lower frequency of atopic dermatitis than patch test negative ones. 16 distinct allergens elicited positive reactions in ≥1% of the children tested. Reactions to nickel sulfate occurred in 15.9% of all children tested, but in 25.0% of girls 14/15 years old, and in only 4.5% of boys 6–13 years old. Double‐sensitizations with cobalt salts, potassium dichromate and palladium were seen. Mercury compounds were found in 2nd place (thimerosal: all children: 11.3%; 6–13 years old: 14.3%, 14/15 years old: 8.0%), followed by fragrance allergens. We conclude that contact allergy in children is related to their sex and age. Prophylaxis against nickel, mercury, and fragrance allergy needs to be improved. A shortened standard series may be sufficient for testing children.

Contact allergies in healthcare workers. Results from the IVDK.

Healthcare workers often suffer from occupational skin disease frequently caused by allergic sensitization. Therefore the patch-test results and important patient history items of 31,849 patients recorded between 1992 and 1995 in the 24 allergy departments participating in the Information Network of Departments of Dermatology (IVDK) were evaluated. Significantly increased sensitization rates common to the healthcare sector as a whole were found for the vaccine preservative thiomersal (12.6% vs. 4.9%), the surface and instrument disinfectants glutardialdehyde (9.9% vs. 2.6%), formaldehyde (3.6% vs. 2.1%) and glyoxal (4.2% vs. 1.4%), and for the compounds of the thiuram mix (6.7% vs. 2.6%) present in protective gloves. Formaldehyde seems to lose its importance, but glyoxal must be added to the list of occupational allergens in the healthcare sector. In addition, occupation-specific sensitization was observed, with fragrances in massage therapists (16.1% vs. 10.6%) and nurses (13.8% vs. 11.4%), as well as with methacrylates in dental technicians. The often assumed importance of drugs as type-IV allergens was not confirmed, at least in terms of quantity. The identification of subgroups of increased risk and of occupation-specific allergens could be the basis of targeted preventive action in the healthcare sector.

Recent increase in allergic reactions to methylchloroisothiazolinone/methylisothiazolinone: is methylisothiazolinone the culprit?

Background. The frequency of sensitization to methylchloroisothiazolinone (MCI)/ methylisothiazolinone (MI) observed in the Information Network of Departments of Dermatology (IVDK) was constantly around 2.1% from 1998 to 2009. After that, it increased to 3.9% in 2011, paralleled by an increase in the frequency of allergic reactions to MI in the preservative series from 1.9% in 2009 to 4.4% in 2011. MI without MCI has increasingly been used as a preservative in cosmetics and skin care products in recent years.

Contact allergy to ingredients of hair cosmetics in female hairdressers and clients – an 8-year analysis of IVDK data*

Not only hairdressers, but also their clients or home‐users of hair cosmetic products may become sensitized to one of the product constituents. The present analysis addresses the question whether the pattern of sensitization is different in these 2 groups and includes female patients who consulted with the participating centres of the IVDK (http://www.ivdk.org) between 1995 and 2002, and in whom hair cosmetics have been considered as being causative of their contact dermatitis. Among these, 2 subgroups were identified: (i) patients, currently or previously working as hairdressers, diagnosed with occupational skin disease (H, n = 884) and (ii) patients who never worked as hairdressers, i.e. clients (C, n = 1217). Previous atopic eczema was twice as common among H, who were also much younger (median age 24 versus 46 in C). Analysis of sensitization frequencies and patterns showed the well‐known decline of contact allergy to glyceryl monothioglycolate (GMTG) in H from 31.2% to 8.5%. Among the C, 1.7% were allergic to GMTG. Concerning p‐phenylenediamine, a steady decline from 27.6% to 17.2% was observed in H, while no trend was found in C (12.6% and 16.6% in the first and the last 2‐year period, respectively). Conversely, a very slight decline of p‐toluenediamine sensitization was observed in H (from 29.5% to 24.8%), while at the same time a significant increase was noted in C (from 8.7% to 16.7%). A slighter increase was also noted with ammonium persulfate in C (3.1–6.8%), while the proportion of H sensitized remained largely constant at about 26%.

Contact allergy to preservatives. Analysis of IVDK data 1996–2009

Background  Preservatives are well‐known and important contact allergens.