Evidenzbasierte Beurteilung der Auswirkung von Typ-IV-Allergien bei der Minderung der Erwerbsfähigkeit

Evidence-based guidelines about the distribution of type IV allergens of the European standard series in different professions and its occupational relevance are missing. Based on published data, epidemiological investigations, work related knowledge about industrial processes, and allergen specific properties, recommendations are given about the clinical impact in the working environment for the following allergens: acrylates/methacrylates, epoxy resins, dichromate, cobalt, nickel, formaldehyde, (chlor-)methylisothiazolone, p-phenylendiamine, colophony, thiurame, mercaptobenzothiazole, dithiocarbamate, n-isopropyl-n'-phenyl-p-phenylendiamine, fragrance mix, composite mix, and neomycinsulfate. These recommendations might improve the clearance rate and allergological evaluation of the occupational relevance of different delayed type sensitizations or allergens.

Evidenzbasierte Dermatologie und die Cochrane Skin Group

The concept of evidence based medicine (EBM) has represented a paradigm shift in medical thinking and practise in the last decade. However, we seem to be stuck with the phrase, yet it is a term that is frequently abused and misunderstood. Therefore, the purpose of this article is to clarify what evidence based dermatology (EBD) is and what it is not. Some guidance on the four key steps in practising EBM in dermatology will be given. The central role of systematic reviews will be elaborated and the Cochrane skin group introduced. Finally, the limitation of EBD will be discussed.

[Pruritus in pregnancy. A frequent diagnostic and therapeutic challenge]

Pruritus is the leading dermatological symptom during pregnancy. Besides preexisting or acquired dermatoses, there are a number of pregnancy-specific dermatological diseases such as PEP (polymorphic eruption of pregnancy, previously named PUPPP), pemphigoid (herpes) gestationis, and pruritus gravidarum that are accompanied by severe itching and scratching. Because of potential effects on the fetus, the treatment of pruritus in pregnancy requires prudent consideration. The use of topical and systemic treatments depends on the underlying aetiology of pruritus and the stage and status of the skin. In general, emollients, topical anti-pruritics and topical corticosteroids appear to be the safest options for localised forms of pruritus in pregnancy whereas systemic treatments and/or UV phototherapy are adequate for generalized pruritus. Systemic corticosteroids and a restricted number of antihistamines may be administered in severe cases. This paper highlights the major aetiologies of pruritus during pregnancy and points out the cornerstones of antipruritic therapy in recognition of our own clinical experiences and the current literature.

[Pruritus in childhood. A diagnostic and therapeutic challenge]

From the clinician's point of view, pruritus in children is quite frequent. It mainly occurs along with dermatoses but rarely with systemic diseases such as renal and liver failure or with genetic disorders. Mostly, it appears in the setting of atopic dermatitis (AD). Other frequent differential diagnoses comprise e.g. scabies, impetigo, varicella, tinea, urticaria, mastocytosis and psoriasis. In children, pruritus is most often associated with severe scratching leading to artefacts. This group of patients requires a therapeutical regimen of its own. The use of topical and systemic treatments depends on the underlying aetiology of pruritus and the stage and status of the skin. The physician has to consider that topically applied drugs may cause intoxication due to the different body volume/body surface proportion, especially in newborns and infants. The dosages of systemic drugs need to be adapted in children and UV phototherapy should be performed with caution due to possible longterm photo damage of the skin. Physicians feel more insecurity treating pruritus in children, especially when systemic treatments are taken into consideration. We want to highlight the major aetiologies of pruritus in children and point out the cornerstones of antipruritic therapy in this challenging group of patients in recognition of our own clinical experiences and the current literature.

[Hydroxyethyl starch-(HES)-induced pruritus as secondary complication of an occupational accident]

A 29-year old employee (controller in the textile industry) had an occupational accident leading to a femoral fracture. After surgery, he developed acute respiratory distress syndrome (ARDS) necessitating intensive care treatment. Three weeks after the accident, he developed generalized severe itching on a daily basis unresponsive to systemic and topical treatments. After one year, the itching had decreased to approximately 50% of its initial intensity. Hydroxyethyl starch (HES)-induced pruritus was diagnosed, based on the typical history and clinical features, the proven administration of HES and its cutaneous tissue storage by electron microscopy. Drug-induced pruritus caused by the plasma expander hydroxyethyl starch can be a secondary consequence of an occupational accident and thus an issue in accident compensation claims.

Overview of studies of treatments for hand eczema-the EDEN hand eczema survey

BACKGROUND

Hand eczema is a major cause of morbidity and lost earnings. Many interventions ranging from topical steroids to oral ciclosporin are used, but their evidence base and the best methods to assess their efficacy are uncertain.

OBJECTIVES

As part of a long-term project to improve standards of design and reporting in hand eczema trials, we sought to describe the prevalent study designs and comment on the quality of reporting of such studies. METHODS AND DATA SOURCES: Electronic databases (Cochrane, Medline, Embase, Pascal, Jicst-Eplus, Amed) were searched from January 1977 to April 2003 using all possible variants of the terms hand and eczema/dermatitis. In addition, four general medical and 17 specialist dermatology journals were hand-searched by pairs of researchers for all possible therapeutic studies.

STUDY SELECTION

Studies were eligible for inclusion if they dealt with hand eczema as diagnosed by a physician irrespective of the aetiology, and if they described the results of a study of a therapeutic intervention in humans. Single case reports and reviews were excluded, but case series and nonrandomized studies were considered alongside randomized studies. Data selection For each study, two researchers independently assessed the type of study, outcome measures, enrolment criteria, randomization, masking of interventions and how losses to follow-up were dealt with.

MAIN OUTCOME MEASURES

Proportion of studies according to type of intervention and study type. Proportion of randomized controlled trials (RCTs) that adequately reported eligibility criteria, randomization generation and concealment, masking and intention-to-treat analysis.

RESULTS

A total of 90 studies reported in 87 papers dealt with 11 different classes of interventions. Around 80% of the studies dealt with just four interventions: ultraviolet light, topical steroids, radiation and systemic immunosuppressives. Of the 90 studies, 44 were case series, 15 were nonrandomized controlled trials, and the remaining 31 were RCTs. Of the 31 RCTs, 16 were parallel (one with cross-over design) and 15 self-controlled. Only 11 of the RCTs adequately reported eligibility criteria. The randomization method was described in 10, and there was adequate concealment of allocation in eight. Masking the treatment allocation from both the study assessors and patients was done in 11 RCTs, and intention-to-treat analysis was reported in four. Only 13 RCTs were 4 months or longer in duration. No study reported a rationale for the sample size, and in only one study had the outcome variable been validated.

CONCLUSIONS

Most 'trials' in hand eczema are not RCTs. Internally controlled (left/right) studies were common. Based on the poor overall quality of reporting, most RCTs of hand eczema trials are not adequate to guide clinical practice. Future trials of hand eczema should be randomized, using a parallel group or self-controlled design. Research is needed to develop validated and clinically relevant outcome measures. Most of the remaining issues relating to poor quality of existing evidence can be relatively easily dealt with by following the CONSORT guidelines.

[Skin cancer and occupational disease]

Although it is universally accepted that UV light exposure can cause malignant skin tumors, UV-induced skin cancers are not recognized as an occupational disease in Germany. Exposure to natural or artificial UV light occurs in many work places, so that the induction of occupational skin cancers is certainly plausible. In recent years, a special clause in the occupational disability rules has recognized some cases of UV-induced skin cancers. We discuss the nature of occupational UV exposure, explore preventative measures and review the data regarding occupational UV-induced skin tumors. After evaluating recent publications, we conclude that for squamous cell carcinoma the epidemiological proof of an at least doubled risk (RR >2) due to occupational UV radiation can be given. The clear dose response relationship supports these epidemiological findings. For the individual risk assessment, an attributive UV radiation >40% due to occupational factors must exist. Under those circumstances, squamous cell carcinoma should be recognized and compensated as an occupational disease.

Entwicklung der Chromatallergie in der deutschen Bauwirtschaft

For decades potassium dichromate has been the most important allergen in the construction industry. In Scandinavian countries the prevalence of potassium dichromate sensitization declined following the introduction of low-chromate cement. In contrast, analysis of our register in Northern Bavaria and the data of workers compensation board show no significant decline in potassium dichromate sensitization in the German construction industry during the 1990s. In 1993, German legislation provided an Approved Code of Practice and the cement manufacturers committed themselves to reduce the level of water-soluble chromates to less than 2 ppm in bag cement. Since 2000 this agreement has also included ready-mixed concrete. It remains to be seen, if sensitization against potassium dichromate will decline in the upcoming years. Based on our data, it would be desirable if only low-chromate cement was used in the construction industry in Germany as in Scandinavia.

Internet und Berufsdermatologie

The World Wide Web (WWW) offers physicians as well as their patients a huge resource of health information, which can be attained within minutes. Nevertheless it is difficult to select the needed information out of the mass of provided data and their quality is often poor with many unproven statements. Occupational dermatologists can especially benefit from the internet as they need a wide range of data from many sources. Much of this data can already be obtained via internet. To facilitate their search for information, this article presents a selection of German websites. The quality of the websites has been assessed using criteria such as design, search function, provided links and medical information. The results revealed deficiencies in the transparency of the data, e.g. often it is not apparent who is responsible for the information or when they were updated.

Vaccines for birch pollen allergy based on genetically engineered hypoallergenic derivatives of the major birch pollen allergen, Bet v 1

BACKGROUND

We have recently engineered recombinant derivatives of the major birch pollen allergen Bet v 1 (rBet v 1 fragments and trimer) with strongly reduced allergenic activity.

OBJECTIVE

The aim of this study was the in vivo characterization of potential allergy vaccines based on Al(OH)3-adsorbed genetically modified rBet v 1 derivatives in mice.

METHODS

BALB/c mice were immunized either with courses of nine injections of increasing doses of Al(OH)3-adsorbed rBet v 1 wild-type, rBet v 1 fragments, rBet v 1 trimer or Al(OH)3 alone in weekly intervals or with three high-dose injections applied in intervals of 3 weeks. Humoral immune responses to rBet v 1 wild-type and homologous plant allergens were measured by ELISA and Western blotting, and the ability of mouse antibodies to inhibit the binding of allergic patients IgE to Bet v 1 was studied by ELISA competition experiments.

RESULTS

In both schemes, hypoallergenic rBet v 1 derivatives induced low IgE but high IgG1 responses against rBet v 1 wild-type. The IgG1 antibodies induced by genetically modified rBet v 1 derivatives cross-reacted with natural Bet v 1 and its homologues from alder (Aln g 1) as well as hazel (Cor a 1) and strongly inhibited the binding of birch pollen allergic patients' IgE to Bet v 1 wild-type.

CONCLUSION

Genetically modified hypoallergenic rBet v 1 derivatives induce blocking antibodies in vivo. Their safety and efficacy for the treatment of birch pollen and associated plant allergies can now be evaluated in clinical immunotherapy studies.

Lebensqualit�t bei Patienten mit berufsbedingten Handekzemen

In recent years quality of life has been studied in a growing number of different dermatological diseases. Internationally validated questionnaires such the RAND-36 (identical to the SF-36) do not contain enough questions which are relevant for skin diseases. There is no publication on quality of life issues in occupational skin diseases, and only one short report gives data on quality of life in hand eczema. The widely used skin specific instrument DLQI has only 2 questions that indirectly refer to employment issues. A quality of life questionnaire on occupational skin diseases (mostly hand eczema) should ideally include questions on work-related impairment of both physical functioning and interaction with colleagues.

Occupational skin disease in the construction industry

BACKGROUND

Construction workers have a substantial risk of developing irritant and/or allergic contact dermatitis. Unfortunately, however, there is little population-based epidemiological data relating to occupational skin diseases (OSD) in the European construction industry that allow assessment of preventive measures.

OBJECTIVES

In this investigation, the yearly incidence rates and causes of OSD in the construction industry were analysed on the basis of our register in Northern Bavaria.

METHODS

From 1990 until 1999, all incidences of OSD in the construction industry were recorded prospectively. This enables the calculation of incidence rates of OSD in relation to the employed population in Northern Bavaria as recorded by the German Federal Employment Office.

RESULTS

In the construction industry, a total of 335 OSD were registered. These comprise 9.0% of all OSD in the register. We classified them into four relevant groups: (A) tile setters and terrazzo workers (incidence per 10 000 employees = 19.9); (B) painters (7.8); (C) construction and cement workers (5.2); and (D) wood processors (2.6). The overall incidence was 5.1 per 10 000 employees over 10 years, which is a little below average for the entire register (6.7). Of these, 43.6% were at least 40 years old. Allergic contact dermatitis (61.5%) occurred more often than irritant contact dermatitis (44.5%). Potassium dichromate caused roughly half of all cases of sensitization found to be occupationally relevant in the construction industry (152 cases) followed by epoxy resin (40) and cobalt chloride (32).

CONCLUSIONS

The results indicate that potassium dichromate is still the most important allergen in the construction industry of Northern Bavaria; there has been no significant decline during the 1990s. This contrasts with the Scandinavian countries, where the prevalence of potassium dichromate sensitization declined following the reduction of chromium VI levels resulting from the addition of ferrous sulphate to cement. Within the construction industry, tile setters and terrazzo workers have a strikingly high incidence of OSD.

Neurodermitisschulung

Atopic eczema (AE) is a common, chronically relapsing, inflammatory skin disease with an early onset during infancy associated with a high loss of quality of life and socioeconomic burden. In the past few years, an Atopic Eczema Prevention Program was established to improve disease management and the quality of life of patients with atopic eczema. In Germany, the Task Force on Education Programs for Atopic Eczema (AGNES = Arbeitsgemeinschaft Neurodermitis Schulung) for children, youths, and parents was founded as well as the Task Force on Dermatological Prevention (ADP) for adults. These groups ensure structure and process quality of the prevention programs and organize train-the-trainer workshops. In a randomized prospective controlled trial (the German Randomized Intervention Multicenter Study = GRIMS), we are currently comparing the effectiveness of an atopic eczema group intervention program in (1) parents of atopic eczema children aged 0-7 years, (2) parents and children 7-12 years old, and (3) youths with AE aged between 13 and 18 years. The groups were randomized and compared with a waiting control group. The design and first results will be reported.

[Demographic changes in Germany. Consequences in health policy and dermatology]

During the last century the median life expectancy increased by about 30 years in Germany. According to recent prognoses, this trend will continue over the next decades. Not only the number of people older than 60 years but also its percentage within the population has and will continue to increase dramatically. This has important socio-economic, political and health-economic consequences. The increasingly older population has an important impact on dermatology. The incidence of many skin diseases increases with age because of long-term exposure to exogenous factors such as UV irradiation. Aging processes especially affect the skin. Last not least, the distinction between skin disease and "cosmetic" skin problems has changed in the last decades in our society. Even a small reduction in the threshold of what the public and health professionals regard as a skin complaint worthy of medical attention could lead to a large increase in future dermatology service requirements. The demographic changes in our society are becoming an important issue in dermatological health care research.

Occupational relevance of positive standard patch-test results in employed persons with an initial report of an occupational skin disease

OBJECTIVES

It is commonly accepted that the standard screening tray is an essential diagnostic test in patch testing supporting the diagnosis of contact dermatitis, the most common type of occupational skin disease (OSD). In this study standard patch-test results of employed persons with an initial report of an OSD were analyzed within 24 occupational groups.

METHODS

An evaluation was made of employed persons recorded in the Register of Occupational Skin Diseases in Northern Bavaria (Berufskrankheitenregister Haut-Nordbayern; BKH-N) between 1990 and 1999, catering for those standard screening tray allergens tested over the 10-year period.

RESULTS

Nickel sulfate was the most common sensitizer (29.5%), showing occupational relevance in only 11% of the cases sensitized. Other common sensitizers were cobalt chloride (13.5%), p-phenylenediamine free base (10.7%), potassium dichromate (9.8%), fragrance mix (5.4%), thiuram mix (4.2%), balsam of Peru (4.0%), chloromethylisothiazolinone/methylisothiazolinone (4.0%), and formaldehyde (4.0%). The most occupationally relevant sensitizers were thiuram mix (71%), epoxy resin (67%), p-phenylenediamine free base (59%), p-phenylenediamine-black-rubber mix/ N-isopropyl- N'-phenyl- p-phenylenediamine (53%), potassium dichromate (48%), formaldehyde (38%), chloromethylisothiazolinone/methylisothiazolinone (37%), and mercapto-mix/mercaptobenzothiazole (35%). Occupational groups at risk of acquiring delayed-type sensitization were, in particular, electroplaters, tile setters and terrazzo workers, construction and cement workers, solderers, wood processors, and leather and fur processors.

CONCLUSIONS

The standard series contributes valuable information and asserts its position in clarifying the causes of OSDs. Based on the study results, the rate of occupationally relevant sensitization to each single allergen is demonstrated, and the difficulties in verifying the occupational relevance are discussed.

Impact of anatomical location on barrier recovery, surface pH and stratum corneum hydration after acute barrier disruption

BACKGROUND

It is not known whether distinct anatomical locations will respond with different recovery rates following acute barrier challenges.

OBJECTIVES

To investigate whether barrier parameters differ at five body sites during recovery from acute disruption.

METHODS

Acute barrier disruption was achieved by tape stripping and by acetone extraction of stratum corneum lipids. Transepidermal water loss (to assess barrier function), capacitance (for stratum corneum hydration) and skin surface pH were measured at each of five different body sites in 14 human volunteers. Individual measurements were obtained every 24 h for 96 h.

RESULTS

Lipid-rich skin areas (e.g. the forehead) were the most vulnerable to barrier disruption by either method. While acetone treatment affected barrier function and decreased stratum corneum hydration, tape stripping similarly altered barrier function but increased capacitance values. Although the effect of barrier disruption on surface pH appeared to vary with location, no significant pattern of variation emerged. Independent of the method used for barrier disruption, the pH normalized within 96 h.

CONCLUSIONS

Skin at different body sites shows distinct patterns of barrier recovery that are likely to be related to structural and physiological differences. Therefore, 'anatomically specific' regimens appear possible and relevant for the treatment of cutaneous disorders. In addition, adequate statistical analyses are essential to detect real differences in barrier recovery parameters.

Monitoring levels of preservative sensitivity in Europe. A 10-year overview (1991-2000)

A 10-year multicentre analysis of the frequency of sensitivity to common preservatives collected in 16 centres in 11 countries has shown stable but persisting high levels of sensitivity to formaldehyde and 5-chloro-2-methyl-4-isothiazolin-3-one + 2-methyl-4-isothiazolin-3-one (MCI/MI). It has also revealed a significant increase in the level of reactivity to methyldibromoglutaronitrile (MDBGN) from 0.7% in 1991 to 3.5% in 2000. The current high level of sensitivity to MDBGN requires an urgent safety re-evaluation and risk assessment update along with consideration of immediate lowering of use concentrations, especially in leave-on products.

Surveillance scheme for occupational skin disease in the Saarland, FRG. First report from BKH-S

Occupational skin disease (OSD) is a significant public health concern. To keep OSDs under surveillance, a register of OSDs (BKH-S) was implemented in 1999 in the Saarland, FRG. We conducted a population-based register study to analyse all initial reports of OSDs reported to the BKH-S. 336 cases were prospectively assessed from July 1999 to June 2001. In 78% (n = 263) of the cases an occupational cause for the skin disease was stated, 91% (n = 240) of which fell within 16 occupational groups. This is equivalent to 6.8 cases per 10,000 workers per year within these occupational groups. Notably, young age groups (median age 35 years) were affected with a female predominance. The most frequent final diagnosis was irritant contact dermatitis (75%) followed by allergic contact dermatitis (34%) and atopic dermatitis (19%). The overall prevalence of occupationally relevant delayed-type reactors was 21% and of immediate-type reactors 17%. Work-related delayed-type sensitizations to potassium dichromate (n = 8) and immediate-type sensitizations to natural rubber latex (n = 11) were the most frequently observed. Questionnaire results showed frequent occupational skin contact with wet work (59%), detergents (48%), and disinfectants (38%). The second valid surveillance scheme for OSD in the FRG has been introduced and can be made available for further analysis.

Breastfeeding duration is a risk factor for atopic eczema

BACKGROUND

The results of numerous studies on the influence of breastfeeding in the prevention of atopic disorders are often contradictory. One of the most important problems is confounding by other lifestyle factors.

OBJECTIVE

The aim of the present study was to analyse the effect of any breastfeeding duration on the prevalence of atopic eczema in the first seven years of life taking into account other risk factors.

METHODS

In an observational birth cohort study 1314 infants born in 1990 were followed-up for seven years. At 3, 6, 12, 18, 24 months and every year thereafter, parents were interviewed and filled in questionnaires, children were examined and blood was taken for in vitro allergy tests. Generalized Estimation Equations (GEE)-models were used to model risk factors for the prevalence of atopic eczema and for confounder adjustment

RESULTS

Breastfeeding was carried out for longer if at least one parent had eczema, the mother was older, did not smoke in pregnancy, and the family had a high social status. The prevalence of atopic eczema in the first seven years increased with each year of age (OR 1.05; 95% CI 1.01-1.09 for each year), with each additional month of breastfeeding (1.03; 1.00-1.06 for each additional month), with a history of parental atopic eczema (2.06; 1.38-3.08), and if other atopic signs and symptoms appeared, especially specific sensitization (1.53; 1.25-1.88), and asthma (1.41; 1.07-1.85). Although breastfeeding should be recommended for all infants, it does not prevent eczema in children with a genetic risk.

CONCLUSION

Parental eczema is the major risk factor for eczema. But in this study, each month of breastfeeding also increased the risk.

Natural course of sensitization to cow's milk and hen's egg in childhood atopic dermatitis: ETAC study group

BACKGROUND

Sensitization to food allergens has been implicated in the pathogenesis of atopic diseases, in particular atopic dermatitis (AD). The aim of the present paper is to investigate the natural course of sensitization to egg and to cow's milk and its relationship with the severity of AD.

METHODS

The placebo intention-to-treat population of the ETACTM (Early Treatment of the Atopic Child) study consisted of 397 children with AD aged 12-24 months (mean+ SD: 17.2 + 4.1 months) who were followed for 18 months. All children were examined for objective SCORing Atopic Dermatitis (SCORAD) and specific IgE amongst other, to egg and to cow's milk at inclusion and after 3, 12 and 18 months. Fifteen patients were excluded from this analysis due to major protocol violations thus leaving 382 patients in the analysed population.

RESULTS

Sensitization to egg and to cow's milk was more common in atopic children with severe AD at all time-points. At inclusion, children sensitized to both egg and to cow's milk had the most severe AD (Kruskall-Wallis test P= 0.007). The degree of sensitization expressed in RAST classes was significantly related to the severity of AD. Furthermore, children sensitized to egg or to cow's milk at inclusion had a higher risk of persistence of AD (84% and 67%, respectively, vs. 57% in those not sensitized) and a higher objective SCORAD after 18 months follow-up.

CONCLUSION

We found an association between severity of AD and sensitization to egg or to cow's milk. Moreover, sensitization to egg, and to a lesser extent cow's milk, indicates a worse outcome of AD in terms of persistence and severity of the disease.