High frequency of contact allergy to gold sodium thiosulfate

When gold sodium thiosulfate was added to the patch test standard series, positive reactions were obtained in 8.6% of 823 consecutive patients with suspect contact allergy. The test reactions were clinically of an allergic type and, in several cases, long-lasting. There was no correlation with other allergens in the standard series. In a special study on 38 patients with contact allergy to gold sodium thiosulfate, the following principal findings were obtained: positive patch tests to the compound itself in dilute concentration; positive patch tests to potassium dicyanoaurate; negative patch tests to gold sodium thiomalate, sodium thiosulfate, and metallic gold; positive intradermal tests to gold sodium thiomalate. Our findings make gold sodium thiosulfate the 2nd most common contact allergen after nickel sulfate. It is suggested that a positive skin test to gold sodium thiosulfate represents gold allergy.     

Polyvinyl chloride dermatitis not caused by phthalates

Seven cases of contact dermatitis in children due to identification bracelets made of poly-vinyl chloride plastic are reported. Patch tests with the bracelets were negative in the five cases tested. It is concluded that the reactions were irritant due to some unknown chemical in the bracelets.
The most widely used plasticizers in PVC, phthalates, must have very low sensitising properties, as only one positive patch test was found in 1532 patch tests with phthalate mix, performed as a joint study by the International Contact Dermatitis Research Group.     

Allergic contact dermatitis due to phenylephrine hydrochloride, with an unusual patch test reaction

2-day (2-D) closed patch tests are often used in daily clinical practice and useful for evaluating the cause of allergic contact dermatitis. However, even when 2-D closed patch tests at appropriate concentrations are performed for suspected allergic contact dermatitis based on clinical findings, positive reactions are not always obtained. Therefore, although the use of the allergen again induces similar symptoms, a definite diagnosis cannot be made in some cases. We report a case of allergic contact dermatitis due to phenylephrine hydrochloride in eyedrops, with an unusual patch test reaction. Although the results of the routine 2-D closed patch test were negative, a definite diagnosis could be made by closed scratch-patch test. In addition, long-lasting allergic patch test reactions were observed at the positive scratch-patch test site for about 3 months. We speculated that these unusual results on patch testing in our case were associated with the degree of percutaneous absorption of causative agents. Therefore, even when 2-D closed patch tests are negative, scratch-patch tests may be indicated for patients in whom clinical symptoms continue strongly to suggest contact dermatitis.     

Intradermal test in contact allergy to metals.

Variations of intradermal test results were studied in a group of patients with clinically evident contact dermatitis and with the history suggestive of contact with metals and with negative patch tests reactions to the latter. The positive reactions obtained in several cases indicate that intradermal tests may reveal specific sensitivities, which patch tests using standard concentrations are not always capable of demonstrating.     

Plants as the cause of contact allergy diagnosed at the Dermatological Clinic, Medical Academy, in Bia?ystok

In patients with allergic changes hospitalized in the years 1984-1988 in the Department a careful history was obtained for detection of correlations between the appearance of skin lesions and contact with plants. In patients with a positive history patch tests were done with a panel of routine allergens and leaves and/or flowers of certain plants. Positive tests with various plants were obtained in 14 cases. In 6 patients reporting contact with primrose positive tests were obtained with flowers and leaves of this plant, four of five tobacco planters tested who had eczematous lesions of the hands, aave also positive results of the test with tobacco leaves, and in three children reporting contact with butter-cup changes were observed resembling dermatitis pratensis bullosa. In one case allergy to parsnip was demonstrated. It is stressed that plants may give rise to contact dermatitis as well as to allergic-toxic changes.     

Air-borne contact dermatitis caused exclusively by xanthium strumarium

Most cases having air-borne contact dermatitis (ABCD) in India are considered to be caused by Parthenium hysterophorus. In some cases however, other plants have also been noticed to give positive patch test reactions. We are reporting two cases presenting as ABCD who showed positive patch tests with Xanthium strumarium while the patch tests with Parthenium hysterophorus were negative. It is therefore necessary to realise that every case of ABCD is not caused by Parthenium, and patch testing with Parthenium alone can lead to serious mistakes.     

Contact allergy to gold in dental patients

Summary Gold sodium thiosulphate (GSTS) In patch test series commonly yields positive reactions. In this study of dental patients, the clinical relevance of these positive reactions, the suitability of gold compounds as patch test materials, and value of the lymphocyte proliferation test in gold contact allergy, were evaluated. The frequency of positive patch test reactions to GSTS was 12·4% in the dental series. Fifty-two patients, only two of whom were male, were studied. Thirteen (25%) had had symptoms from jewellery or dental restorations. However, in most cases gold allergy was subclinical. A 10% aqueous solution of gold sodium thiomalate (GSTM) was almost as good as 0·5% GSTS in petrolatum as a marker of gold contact allergy, but 0·001% potassium dicyanoaurate (PDCA) yielded a high percentage of false-negative results. Seventy-three per cent of the subjects with positive patch tests to GSTS responded to gold compounds in vitro in the lymphocyte proliferation test, whereas 13 controls without gold contact sensitivity were negative. Consistent results in skin and lymphocyte proliferation tests provide support for the concept that gold salt-induced'allergic-like' reactions are truly allergic in nature.     

Comparison of Personal History with Patch Test Results in Metal Allergy

In order to compare the validity of patient personal history of contact sensitivity to metal alloys with patch test results, 160 patients with hand eczema were patch tested with a standard series according to the ICDRG after a special questionnaire. In 65%, history and patch test results were identical. Seventy-eight (48.8%) patients thought they would be allergic to metal ions, whereas the patch test revealed a positive result in only 21.3% cases. Positive history but negative test was more frequent in women; in the male group, negative history and positive patch test was the most common finding. Although 82 patients had a negative history, the patch test was positive for contact sensitivity to metal allergens in 12 of them. Both false positive patch tests and false negative histories are possible. Since many factors influence a positive patch test, not only the patient's history but also a synopsis of the anamnesis and patch testing will help to achieve the correct diagnosis of metal contact hypersensitivity.     

A 10-year review of an industrial dermatitis clinic

During a 10-year period, 678 patients were seen al an occupational dermatitis clinic attached to a District General Hospital. Of these, 424 were accepted as having an occupational dermatosis. The pattern of skin lesions and the patch test findings were those associated with a diversified light industrial selling coupled with a large traditional furniture industry. Fifty-one per cent of all cases were regarded as being allergic but the proportion varied greatly from one industry to another. Positive patch tests were obtained to the Standard European Series in 50.3% but additional tests increased this to 64%. In the furniture industry most of the positive reactions occurred only with such additional tests. The significance of the patch test reactions is discussed in relation to the findings in 992 unselected patients seen in the contact dermatitis clinic during; i 3-year period.     

Patch,prick or intradermal tests to detect delayed hypersensitivity to corticosteroids?

Background. Contact allergy to topical corticosteroids is usually detected by patch testing. Objectives. This study compares the test results obtained with patch, prick and intradermal testing, to assess the most sensitive method for diagnosing corticosteroid hypersensitivity. Patients/Methods. Nineteen corticosteroid‐allergic subjects and three control subjects were included. Patch, prick and intradermal tests were performed with five commercial corticosteroid preparations, as well as with the respective active principles diluted in ethanol. The test readings were performed at different time points, i.e. at 8, 24, 48 and 96 hr, and at 7 days. Results. Patch tests with ethanolic preparations produced more positive reactions than the commercial ones. The intradermal tests became positive earlier than the patch tests, a concordance between patch and intradermal tests being found in 11/15 (two positive intradermal test results with negative patch test results and vice versa). However, several subjects developed skin atrophy (14/22) at intradermal injection sites. Conclusion. Patch testing with the active principles diluted in ethanol remains the diagnostic method of choice for the detection of delayed hypersensitivity to corticosteroids. Intradermal tests with late readings, despite detecting additional contact allergy cases, should not be routinely performed, because of an important risk of atrophy, particularly with corticosteroid suspensions.     

Allergic contact dermatitis from rosin used as soldering flux

Two cases of allergic contact dermatitis from soldering fluxes are reported. Both were caused by rosin (colophony). One case was confirmed by a positive patch test to rosin purchased from a commercial European patch test supplier. The other could be confirmed only by a positive patch test to the specific rosin used to flux the solder; repeated patch tests to rosin purchased from the same European supplier were negative. Dermatitis from soldering fluxes is reviewed.     

Incidence of contact allergy in patients with eczema nummulare

In patients with eczema nummulare patch tests with a panel of 18 allergens were done with positive result in 9 (18%) cases. In 6 cases multivalent allergy was found. Most frequently positive tests were obtained with potassium dichromate. The tests showed participation of contact allergy in the development of changes in a part of patients with eczema nummulare.     

Sensitization to reactive textile dyes in patients with contact dermatitis

Reactive dyes are used especially for colouring natural fibres (cotton, silk and wool) that arc widely used in Western countries, particularly Italy, in the production of clothes. The aim of our study was to investigate sensitization to the most commonly used reactive textile dyes in patients undergoing patch tests, and to assess the clinical relevance of contact sensitization of these dyes. 1813 consecutive patients underwent patch tests with the GIRDCA standard series and an additional textile series of 12 reactive dyes. 18 of these patients were sensitized to reactive dyes (0.99) (4 only to reactive dyes). The dyes most frequently responsible for positive patch tests were Red Cibacron CR and Violet Remazol 5R (respectively, 8 and 5 positivities). In 5 cases only was a history of intolerance to particular garments given; of 4 patch tests performed with pieces of garment, 2 were positive. In 1 occupationally-exposed patient, airborne contact dermatitis was suspected. Owing to the lack of up-to-date patch test series, some cases of allergic contact dermatitis from textile dyes are probably misdiagnosed: new colouring agents are continuously introduced to the market, so that a close relationship with textile industry is necessary to improve our diagnostic tools.     

Contact urticaria to commercial fish in atopic persons

The frequency of contact urticaria provoked by certain fish prepared in the Danish fish industry was examined in 14 persons with atopia. In 71.4% of the test persons we found positive confirmation in a 20-minute scratch patch test to one or more fish species. All occluded patch tests were negative, while 33.9% of the scratch patch tests were positive. It was impossible to make a correlation between positive scratch patch tests and atopic allergen/total IgE. The investigation emphasizes that atopics have a higher frequency of contact urticaria to fish than have non-atopics.     

Contact dermatitis from antioxidants

In a search for contact sensitivity to antioxidants we patch tested consecutive patients referred with eczematous dermatitis. Six cases of allergic contact sensitivity to nordihydroguairetic acid (NDGA) were observed. Three had been sensitized by one brand of cream containing 0.1% NDGA, in three patients the source of sensitization could not be traced. In four patients we found positive patch tests to butylated hydroxyanisole and/or to butylated hydroxytoluene. In two cases the positive patch tests were relevant, since both patients remained asymptomatic when antioxidants were avoided in food. They both had acute flares of vesicular eczema on the fingers after oral administration of small amounts. Gallate esters and Vitamin E (d,l-alpha-tocopherol) each gave one unexplained positive patch test. The present data suggest that further search for hidden sensitizers in topical medicaments and cosmetics is warranted. A declaration of all ingredients in industrial products should be placed on the label.     

Statistical evaluation of the persistence of acquired hypersensitivity by standardized patch tests

Numerous studies have focused attention on the influence of various biological and environmental factors on contact hypersensitivity. In order to evaluate the persistence and/or modification of allergic contact sensitivity 10 a number of common contact sensitizers, the same standardized patch tests were repeated on 174 subjects with contact sensitivity after a lime lapse of 5 years (1987–1992). In 18.4% of the cases, 1 or more sensitivities were lost: 28.7% of the patients had a higher number of positive patch tests after 5 years, while the remaining 52.9% of the patients showed no change in the number of positive patch tests. In 88%, the positive allergens were unchanged, whereas in the remaining 12% of the subjects, they showed 1 or more variations. The association between the allergens most often positive was calculated for both the 1st and the 2nd patch lest results. Moreover, to evaluate the frequency of an allergen's positivity. We studied the disappearance of old sensitivities and the appearance of new sensitivities by the McNemar test. Cobalt chloride was the only allergen with a significant frequency of new positivities over the period of observation ( p < 0.01). Logistic regression analysis was performed to evaluate the possible influence of positive tests to other allergens, and of some clinical findings associated with contact dermatitis, on the sensitivity to cobalt chloride in 1987 and in 1992.     

Allergic contact dermatitis from a pyridine derivative in polyvinyl chloride leather.

Antimicrobial coating of household products has gained wide acceptance in Japan in the past several years. Pyridine derivatives, used as antifungal or antibacterial agents in many common products, are known to cause contact dermatitis. We present a case of severe contact dermatitis caused by a pyridine derivative used as an antifungal agent in the polyvinyl chloride (PVC) leather of a chair. An open patch test was performed with each ingredient of the PVC leather. Other products were previously eliminated from consideration based on a series of negative patch tests. The PVC leather obtained from the patient's chair gave a ++ reaction with evident blistering, according to the International Contact Dermatitis Research Group standard. Fifteen ingredients of the PVC leather were open patch tested; a positive reaction was found with 2,3,5,6-tetrachloro-4 (methylsulphonyl) pyridine (1% in petrolatum). Clinicians should be aware that antifungal or antibacterial agents may be increasingly incorporated into common household products and should be suspected in cases of contact dermatitis.     

Patch testing with methyldibromo glutaronitrile, a multicentre study within the EECDRG

Contact allergy to and allergic contact dermatitis from methyldibromo glutaronitrile (MDBGN) have frequently been reported. As there has been no agreement on which MDBGN test preparation to use, a study was initiated to help determine the optimal patch test preparation for MDBGN. 2661 consecutively patch tested patients at 11 test clinics representing 9 European countries participated. Petrolatum preparations with MDBGN at 1.0%, 0.5%, 0.3% and 0.1% were inserted in the standard series. Contact allergy rates were noted in the range 4.4-1.1% following decreasing test concentrations. Reactions not fulfilling all criteria to be classified as allergic reactions could represent either weak allergic or irritant reactions, and such reactions were noted in the range 8.2-0.5% with decreasing concentrations. A significant number of these reactions represented weak allergic reactions, as allergic reactions were obtained to higher patch test concentrations in the same individual. Morphologically irritant reactions were noted only for the highest test concentrations. In summary, the contact allergy rates and frequencies of doubtful and irritant reactions vary with the patch test concentration. The final decision on patch test concentration for MDBGN should not only rely on these factors but also include information on patch test concentrations required to diagnose individual cases with allergic contact dermatitis from MDBGN as well as results of repeated open application tests.     

Clinical and experimental studies of octocrylene's allergenic potency

Background. Reports of positive patch test and photopatch test reactions to the chemical ultraviolet filter octocrylene have increased during the last decade. Little is known about the reason for octocrylene's allergenic activity. Objectives. To present and discuss the results of patch tests and photopatch tests with octocrylene, and to investigate the possible cause of its allergenic properties. Methods. Results of patch tests and photopatch tests with octocrylene in patients with adverse skin reactions to sunscreen products and/or ketoprofen were collected. The allergenic potency of octocrylene was investigated in the murine local lymph node assay (LLNA). Chemical reactivity assays were used to mimic octocrylene's interaction with biomolecules. Results. We report 23 cases of positive test reactions to octocrylene (5 patch test and 18 photopatch). Notably, many of these patients also had positive photopatch test reactions to ketoprofen and benzophenone‐3. Octocrylene was shown to be a moderate sensitizer in the LLNA, and it reacted with amines such as lysine, but not with thiols such as cysteine. Conclusions. The clinical studies show that octocrylene is both a photocontact allergen and a contact allergen. Octocrylene's ability to cause contact allergy is probably attributable to its reactivity towards lysine. To be able to understand why octocrylene causes photocontact allergy, further studies are needed.     

Vitamin e contact allergy: a controversial subject

: Although vitamin E has been described as a source of allergic contact dermatitis (ACD), in only a few cases a true sensitization has been confirmed. We describe 2 cases of suspected ACD to vitamin E products. Patch tests and repeated open application tests were performed with the patients' own offending products. Then, patch tests with tocopherol acetate at different concentrations and further patch tests and repeated open application tests with a new sample of the product were carried out. Whereas the first sessions of tests gave positive reactions, the last sessions of tests performed with new samples were negative. Based on these results, we conclude that both our patients probably developed a true vitamin E ACD. However, as vitamin E exerts an anti-inflammatory effect and is an unstable molecule and its allergic potential change during the time, when ACD to vitamin E is tested a bimodal behavior of this molecule may be expected.