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Johannes Geier

Publications and source records attributed to Johannes Geier.

At least 19 recordsLinked to original sources
PubMed2006

White petrolatum (Ph. Eur.) is virtually non-sensitizing. Analysis of IVDK data on 80 000 patients tested between 1992 and 2004 and short discussion of identification and designation of allergens.

UNLABELLED: Sporadic cases of contact allergy to white petrolatum, which is used as a vehicle in patch test preparations, have been reported. The quantitative relevance of the phenomenon remains yet to be elucidated. METHODS: Retrospective analysis of patch test data of the Information Network of Departments of Dermatology (IVDK, http://www.ivdk.org) between 1992 and 2004. RESULTS: Analysis of 79 365 patients patch tested with pure petrolatum yielded 27 '+' (0.03%) and 2 '+++' (0.003%) reactions. The majority of non-negative reactions (0.3%) was interpreted as doubtful (235) or mild irritant (32). The negative reaction index (RI) (-0.8), and the high positivity ratio (PR) (93%) especially a lack of concordance with patch test preparations containing > or=99% petrolatum indicate that many of the 'positive' (+) reactions have to be considered as irritant. There were 2 '+++' reactions. In 1 case, an 'angry back reaction' was confirmed. The other case is probably a reading or documentation error, as the majority of patch test reactions to preparations containing petrolatum remained negative in this case also. CONCLUSIONS: True allergic patch test reactions to white petrolatum are extremely rare and probably due to an individually increased susceptibility to allergens and/or irritants. This is in agreement with considering petrolatum as a non-sensitizer.

Allergens↗
PubMed2006

Patch testing with components of water-based metalworking fluids: results of a multicentre study with a second series.

BACKGROUND: Although many allergens in metalworking fluids (MWF) are identified, there are still some MWF components, which are not sufficiently investigated concerning their sensitizing properties. OBJECTIVES: To investigate sensitization to 10 frequently used MWF components, which are not part of the established MWF test series, in metalworkers with suspected occupational dermatitis due to MWF. PATIENTS/METHODS: Oleyl alcohol, myristyl alcohol, dimethylolurea, 4,4'-methylenebis morpholine, imazalil, 1-amino-2-propanol (monoisopropanolamine; MIPA), 2-amino-2-ethyl-1,3-propanediol (AEPD), 2,5-bis(n-octyldithio)-1,3,4-thiadiazole, zinc alkyl dithiophosphate and dibenzyl disulfide have been patch tested in 144 patients. RESULTS: 7 patients reacted positively to the formaldehyde releaser 4,4'-methylenebis morpholine, and 6 of these patients also reacted to formaldehyde and/or other formaldehyde releasers. 4 patients reacted positively to myristyl alcohol tested at 10% petrolatum (pet.). Additionally, 20 doubtful or irritant reactions occurred. 1 patient each reacted positively to oleyl alcohol, MIPA, and AEPD. None of the other test substances mentioned above elicited any clear-cut positive reaction. Patch testing with well-known MWF allergens showed proportions of positive reactions, which were comparable to those from other studies, e.g. 11% to monoethanolamine, 8% to colophonium and 3%-5% to various preservatives. CONCLUSIONS: 4,4'-methylenebis morpholine may be an important MWF allergen, although clinical relevance could not be stated definitely in every case. Myristyl alcohol should not be patch tested at 10% pet., but at a lesser concentration, due to irritant properties.

Adult↗
PubMed2005

Patch testing with p-toluene diamine preparations of different ages.

Analyses of the stability of 1% p-toluene diamine (PTD) in petrolatum used for patch testing showed a rapid decline of the PTD concentration down to 0.1%, possibly due to the generation of dye complexes. To study whether the diagnostic quality of this test preparation is compromised by the chemical reactions taken place, a multicentre study was conducted by the German Contact Dermatitis Research Group (DKG), comparing patch test results in 177 patients with simultaneously tested PTD preparations of different ages. During the 10-month course of this study, the age of the batches ranged from 2 to 11 months for batch A, from 7 to 16 months for batch B and from 11 to 20 months for batch C. There were no statistically significant differences between reactions to batches A and B, A and C, and B and C. Agreement of patch test reactions to the 3 batches was very good and comparable to the general reproducibility of patch test with standard allergens. The chemical reactions mentioned above apparently do not affect the diagnostic quality of PTD patch test preparations because the true allergen probably is not PTD itself, but one or more of the reaction products.

Dermatitis, Contact↗
PubMed2005

Patch testing with patients' own cosmetics and toiletries--results of the IVDK*, 1998-2002.

Patch test results with products brought in by the patients collected by the members of the Information Network of Departments of Dermatology (IVDK) between 1998 and 2002 were analysed. 5911 patients were patch tested with their own cosmetics and toiletries during this period. The 34 082 single test preparations applied to these 5911 patients were manually assigned to 1 of 26 categories, based on the EU Classification Annex I to 76/768/EEC, which had been further refined. The leave-on product category most commonly tested was 'creams, emulsions, lotions, gels and oils for the skin' (n = 3621 tested, n = 312 positive). The rinse-off product type most commonly tested was 'bath and shower preparations' (n = 1333 tested, n = 71 positive). In one-third of patients tested positive to these products, no other positive test result was observed. In the remainder, positive reactions to the fragrance mix, Myroxylon pereirae resin, methyldibromo glutaronitrile, (chloro-)methylisothiazolinone, 2-bromo-2-nitropropane-1,3-diole and further ingredients of cosmetics and toiletries were more common than in product-negative patients. However, in view of the potential for false-positive reactions mainly to rinse-off products, the results must be interpreted with caution. In conclusion, testing of patients' own products can be regarded as efficient and safe, if in accordance with current recommendations.

Adult↗
PubMed2005

Skin-sensitizing and irritant properties of propylene glycol.

In the several publications reviewed in this article, propylene glycol (PG; 1,2-propylene glycol) is described as a very weak contact sensitizer, if at all. However, particular exposures to PG-containing products might be associated with an elevated risk of sensitization. To identify such exposures, we analysed patch test data of 45 138 patients who have been tested with 20% PG in water between 1992 and 2002. Out of these, 1044 patients (2.3%) tested positively, 1083 showed a doubtful, follicular or erythematous reaction (2.4%) and 271 explicit irritant reactions (0.6%). This profile of patch test reactions is indicative of a slightly irritant preparation, and thus, many of the 'weak positive' reactions must probably be interpreted as false positive. No private or occupational exposures associated with an increased risk of PG sensitization were identified, except for lower leg dermatitis. Therefore, according to our patch test data, PG seems to exhibit very low sensitization potential, and the risk for sensitization to PG on uncompromised skin seems to be very low.

Adult↗
PubMed2004

Contact sensitizations in metalworkers with occupational dermatitis exposed to water-based metalworking fluids: results of the research project "FaSt".

BACKGROUND: The composition of water-based metalworking fluids (wb MWF) is complex, and various admixtures may be added before or during usage. Wb MWF may cause irritant as well as allergic contact dermatitis. While several current case reports point towards allergens particularly related to wb MWF, systematic studies have not been performed for several years. From 1999 to 2001, a study on contact allergies among patients with occupational dermatitis (OD) called "Fruhzeitige Erkennung allergener Stoffe bei beruflicher und nicht-beruflicher Exposition" (German acronym: FaSt) was conducted by the Information Network of Departments of Dermatology (IVDK), funded by the employers' liability insurances in Germany (HVBG). OBJECTIVE: The objective of FaSt was to detect sensitization patterns related to particular occupational exposures. METHODS: Anamnestic and clinical data were gathered using a standardised questionnaire. Patch test results were recorded by computer within the IVDK routine procedure. In addition to descriptive statistical analyses, logistic regression analysis was performed to control the effect of potential confounders. RESULTS: Among the 1842 OD patients in the FaSt study, there were 160 metalworkers exposed to wb MWF, whose data is presented in this paper. A specific allergen pattern of these patients can be described: most frequently, sensitizations to monoethanolamine (MEA), colophony/abietic acid, and fragrance mix were observed. Additionally, cobalt, formaldehyde, formaldehyde releasers and other biocides are important allergens in these patients. CONCLUSIONS: Preventive measures and aimed in-depth research may be based on these results. The special MWF test series have to be kept up to date based on exposure information from the MWF industry and on continuous surveillance of the target group.

Adult↗
PubMed2004

Contact allergy in construction workers: results of a multifactorial analysis.

OBJECTIVES: To quantify the risk of contact allergy (CA) to important ubiquitous allergens associated with certain occupations, in particular the construction industry, and to identify possible time trends, controlling for potential confounding variables. METHODS: Bivariate as well as Poisson regression analysis of standardized anamnestic and patch test data comprising 82,561 patients assessed in the 33 German and Austrian contact dermatitis units of the Information Network of Departments of Dermatology (IVDK) between 1992 and 2000. RESULTS: CA to five of the 18 (groups of) allergens considered here were observed significantly more often in construction workers: dichromate, epoxy resin (BADGE), cobalt, thiurams and N-isopropyl-p-phenylenediamine (IPPD). Multifactorial analysis confirmed an increased risk of CA to these allergens in construction workers, compared with other occupations. A very strong association between cobalt and chromate allergy was found in construction workers (OR 39.1, 95% CI 21.1-79.6). CONCLUSIONS: Dichromate is still an prominent allergen in construction workers; as yet, there is only weak evidence of a decrease in Germany. Therefore, the addition of ferrous sulphate to cement, which has been a successful intervention in other countries, should be promoted further. Although CA to other important occupational allergens like thiurams, IPPD and epoxy resin or cobalt (very often associated with dichromate CA) is less frequent, prevention should address these allergens, too. The use of protective gloves with minimal intrinsic CA risk, e.g. due to thiurams in (synthetic) rubber or chromate in leather gloves, should be promoted.

Adult↗
PubMed2004

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.

Bryophyta↗
PubMed2004

Isopropyl myristate recommended for aimed rather than routine patch testing.

Isopropyl myristate (IPM) is considered a very weak sensitizer. Patch test results with 20% IPM in petrolatum (pet.) in 8117 patients and 10% IPM in pet. in 4554 patients between January 1992 and December 2001 by the IVDK are presented. While irritant and questionable reactions were frequently observed, especially with 20% test concentration and 2-day patch test exposure, respectively, and a decrescendo pattern was common, morphologically positive reactions at day 3 were seen in only 16 patients, i.e. altogether 0.13%. In line with previous clinical and experimental evidence, our results indicate that IPM is an extremely weak sensitizer or possibly, in our material, not a sensitizer at all. IPM should thus not be tested routinely, but only in the case of suspected exposure as a possible source of allergic contact dermatitis, e.g. to cosmetics and perfumes, to avoid an unacceptable reduction of the positive predictive value of the test.

Adult↗
PubMed2004

Patch test results with the metalworking fluid series of the German Contact Dermatitis Research Group (DKG).

Based on the information of the interdisciplinary task force on allergy diagnostics in the metal branch, in 2001, the German Contact Dermatitis Research Group (DKG) compiled two metalworking fluid (MWF) test series with currently and previously used components, respectively. After 2 years of patch testing, we present results obtained with these series, based on data of the Information Network of Departments of Dermatology (IVDK). 251 metalworkers who were patch tested because of suspected MWF dermatitis in 2002 and 2003 were included in this retrospective data analysis. Of these, 206 were tested with the current MWF series and 155 with the historical MWF series. Among the current MWF allergens, monoethanolamine ranked 1st with 11.6% positive reactions. Diethanolamine (3.0%), triethanolamine (1.1%), and diglycolamine (1.9%) elicited positive reactions far less frequently. Allergic reactions to p-aminoazobenzene were frequently observed (6.0%), but the relevance of these reactions is still obscure. Positive reactions to biocides ranged from 4.5% for Bioban CS 1135 to 0.5% for iodopropynyl butylcarbamate and 2-phenoxyethanol. Concomitant reactions to formaldehyde, which caused positive reactions in 3.3%, and formaldehyde releasers occurred to varying extents without conclusive pattern. No positive reactions were seen to dibutyl phthalate, di-2-ethylhexyl phthalate, tricresyl phosphate, isopropyl myristate or benzotriazole. With the historical MWF test series, positive reactions to methyldibromo glutaronitrile (MDBGN) were observed most frequently. However, sensitization via allergen sources other than MWF seems likely, as MDBGN, during the study period, has been one of the most frequent preservative allergens in cosmetics and body care products. Other historical MWF allergens comprised morpholinyl mercaptobenzothiazole (3.3%), benzisothiazolinone (BIT; 2.0%) and Bioban P 1487(1.3%). BIT is currently used in MWF again, so it was shifted to the current MWF test series. As decreasing reaction frequencies to former MWF allergens that are no longer used can be expected, the historical series should be re-evaluated after some years. The test series with current MWF allergens has to be kept up-to-date based on information from industry and to be kept concise by eliminating test substances which never cause positive reactions.

Adolescent↗
PubMed2004

Patch testing with metalworking fluids from the patient's workplace.

In view of the wide variety of components currently used in metalworking fluids (MWF), relevant contact sensitizations may be overlooked, because commercially available MWF test series cannot cover the full spectrum. Hence, patch testing with MWF from the patient's workplace is an important additional diagnostic tool. However, recommendations on how to perform such patch tests vary. We retrospectively analyzed patch test data of the Department of Dermatology in Dortmund, 1992-2003. In 141 metalworkers tested because of suspected occupational contact dermatitis due to MWF, 829 patch tests with 306 samples of MWF were performed. Water-based MWF (wb MWF) were mainly tested in 2 dilution series, i.e. pure (workplace concentration), 10% aq. and 1% aq., and pure, 50% aq. and 10% aq. Positive reactions to wb MWF occurred in 27 patients. Patch testing with wb MWF at workplace concentration resulted in 16.1% (39/242) positive reactions, with a positivity ratio of 69% and a reaction index of 0. From the analysis of reaction patterns and concomitant reactions, we conclude that most of these positive reactions indicated true contact allergy. With lower concentrations, relevant allergic reactions may be missed. Neat oils were tested as is or diluted from 1 to 50% in olive oil, but no reactions at all were observed. For optimum benefit of patch testing with MWF from the patient's workplace, breakdown testing is recommended. To overcome the time-consuming difficulties associated with this procedure, we propose a centre for information and documentation of contact allergies due to occupational exposure. Furthermore, full declaration of MWF ingredients is desirable.

Adult↗
PubMed2004

Contact allergy to farnesol in 2021 consecutively patch tested patients. Results of the IVDK.

Farnesol is one of the fragrances considered to be a significant contact allergen. Therefore, it was decided by the European Union to label products containing farnesol. Farnesol was tested [5% petrolatum (pet.)] together with the standard series between 1 January 2003 and 30 June 2003 in 2021 consecutive patients, 1243 females and 778 males. Of these, 22 [1.1%, 95% confidence interval (CI): 0.7-1.6%] had a positive reaction to farnesol. 147 (8.1%) of those 1825 tested to Myroxylon pereirae resin (balsam of Peru, 25% pet.) at the same time reacted positively, 143 (7.8%) of those 1823 tested to the fragrance mix (FM) (8% pet.) and 34 (1.9%) of 1831 tested to propolis (10% pet.). With regard to concomitant reactions in farnesol-positive patients, 5 of 22 reacted additionally to the FM [odds ratio (OR): 4.3; CI: 1.53-12.15] and 2 (of these 5) additionally to M. pereirae resin (OR: 1.27; CI: 0.29-5.54). The strongest association was seen to propolis (OR: 6.2; 95% CI: 1.4-27.7). Compared to those with negative reactions to farnesol, the group of patients allergic to farnesol was characterized by a higher proportion of young females and office workers, and the hand and the face were more often affected. In conclusion, farnesol is an important allergen. We recommend that farnesol should be included in a fragrance patch-test preparation and that its use should be regulated for consumer safety reasons. Furthermore, the extent of exposure to farnesol should be further studied.

Adult↗