Systemic contact dermatitis may occur in contact-sensitized individuals when they are exposed to haptens orally, transcutaneously, intravenously or by inhalation. We report the case of a woman developing a diffuse skin eruption after the topical use of Rhus toxicodendron alcoholic extract and the oral introduction of a homeopathic preparation of the same substance for herpes treatment. An open test, performed with the Rhus toxicodendron tincture, showed an erythemato-oedematous response at 48 h and vesicular reaction at 96 h that was still present after 7 days. Patch test with 65% ethyl alcohol gave negative results. The open test performed, as control, in eight healthy informed subjects revealed negative responses to Rhus tincture application. The result is interesting because in Italy, allergic contact dermatitis to Rhus is uncommon and this case increases the understanding of the pathogenetic mechanism leading to systemic contact dermatitis development.

BACKGROUND:Patch testing with additional series (AS) of allergens may be a useful tool in diagnosing allergic contact dermatitis (ACD).OBJECTIVE:Aim of the study was to verify the usefulness, to check the reliability in clinical practice and to evaluate the economic costs of AS previously built up.METHODS:A total of 281 patients with suspicious ACD underwent patch test with the standard series (SS) and with one or more AS (51 among 71 built up).RESULTS:A total of 170 patients (60.5%) showed positive reactions to SS; 116 (41.3%) to AS. Among 582 nonstandard allergens used, 113 (19.4%) elicited 1 or more positive reactions: out of 10,916 patch tests carried out, 260 (2.4%) positive reactions were observed. The correlation between SS and AS indicated that 8.2% patients resulted SS-/AS+, 27.7% SS+/AS-, 32.7% SS+/AS+, 31.3% SS-/AS-. The most frequently used AS showed the following percentages of patients with 1 or more positive reactions: clothes 41.4%, building industry 51.8%, hairdressers 77.3%, textile industry 42.1%, shoes 36.8%. Positive reactions to the most frequently used nonstandard allergens resulted: propylene glycol 0.4%, cobalt chloride 12.6%, phenylmercuric nitrate 2.2%, p-aminophenol 4.5%. The approximate economic cost of patch testing with AS has been evaluated in 1.3 euro per single patch test.CONCLUSION:The cost of patch testing AS is not irrelevant, but it can be compensated by the advantages deriving from the increase of data concerning ACD etiology. A reduction in the number of allergens included in single AS should be performed. Cobalt chloride, taking into account the high percentage of positive reactions observed and its presence in a large number of AS, could be (re)introduced in the standard series.

BACKGROUND:The Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali (GIRDCA) resolved to obtain the most relevant data regarding contact dermatitis (CD) in Italy by means of a multicenter epidemiological study, involving research units (RU) throughout the country. The survey was performed with the collaboration of Generale Per l'Informatica, Rome (GEPIN) over the periods 1984 to 1988 and 1989 to 1993. The analytical study (of a transverse kind) was aimed at supplying prevalence measures. MATERIALS AND METHODS:The number of subjects taking part in the survey was 42,839. All patients underwent patch testing with the GIRDCA standard series and were included in the survey only if the final diagnosis was either CD or eczematous dermatitis caused by contact. The main anamnestic, clinical data, and allergological test results of all patients were codified into a chart, and subsequently transcribed into a data bank. The data were then processed cumulatively and were statistically analysed by a chi-square for trend test. RESULTS:The four most frequent diagnoses (which, when considered together, make up 39,496 cases, or about 92% of all cases) proved to be nonoccupational allergic contact dermatitis (ACD), nonoccupational irritant contact dermatitis (ICD), occupational ACD, and occupational ICD. The haptens most frequently causing positive reactions in the total number of cases over the first 5 years were, in order of frequency: nickel sulphate, potassium dichromate, cobalt chloride, fragrance mix, balsam of Peru, and, in the second 5-year period, nickel sulphate, cobalt chloride, potassium dichromate, fragrance mix, and thimerosal. Occupational CD (ACD and ICD) was present in 11,694 cases overall, corresponding to approximately 27% of the total number of cases examined, and approximately 29% of all CD (including forms of nonoccupational CD). Regarding distribution by sex, a substantial equivalence of males and females for ACD, and a prevalence of females with ICD can be observed. Five occupations were reputed to be responsible for over 60% of total cases of occupational CD (housewives, bricklayers, workers in the metallurgic and mechanical industries, hairdressers, and healthcare personnel). Regarding the pathogenesis, a clearly dominant percentage of ACD may be observed among bricklayers and hairdressers, and of ICD among housewives. The haptens most frequently noted over the entire decade as the cause of positive reaction in occupational ACD were, in order of frequency, potassium dichromate, nickel sulphate, cobalt chloride, p-phenylenediamine and thiuram mix. Nonoccupational CD (ACD and ICD) was present in 27,802 cases overall, corresponding to about 65% of all cases under examination and over 70% of all CD (also including forms of occupational CD). In regard to distribution by sex, a clear dominance of females, as opposed to males, can be noted for ACD and also (although to a lesser extent) for ICD. The main products and materials (ie, components and relative substances) that are pinpointed as being responsible for nonoccupational ACD, were, in order of frequency, clothing accessories, cosmetics, topical pharmaceuticals, and clothing. The haptens most frequently recognized as the cause of positive reactions were, in order of frequency, nickel sulphate, fragrance mix, cobalt chloride, balsam of Peru, potassium dichromate, ethylenediamine, and diaminodiphenylmethane.

A multicenter study was performed in 12 Italian medical centers by members of Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali (GIRDCA) over 5 years (January 1984 to December 1988) to set up a computerized data bank on contact dermatitis. With a subsequent analytical study, the significance of trends of individual data was computed by using the chisquared test and a linear regression analysis. As to the distribution of the population under review (23,541 cases) in relation to the etiology, nonoccupational causes turned out to be responsible for contact dermatitis (CD) in more than 60% of cases, and, according to the pathogenesis, more than 60% of CDs are allergic contact dermatitis (ACD). Occupational ACD tends to decrease significantly and, on the contrary, tends to increase with time in cases of nonoccupational irritant contact dermatitis (ICD). In occupational CD after an initial prevalence of the allergic pathogenesis, irritation takes over while among nonoccupational forms allergics still clearly prevail. Clothing accessories made of metal and costume jewelry (39.6%), cosmetics (29.3%), medicaments (14.6%), and clothing (9.4%) are the main etiological factors in nonoccupational ACD. In the workplace, five professions (housewives, construction workers, workers in the metallurgical and mechanical industries, hairdressers, and health care providers) cause more than 60% of the cases of CD. The total values and percentages of positive reactions to patch tests for occupational and nonoccupational ACD manifest significant changes in time for some haptens, in particular, a trend toward an increase in nickel sulphate and wool alcohols and a decrease in thiuram mix, neomycin, p-phenylenediamine (PPD), Peru balsam, ethylenediamine, formaldehyde, and carba mix.

Reports in the literature [1] indicate that dermatological risk is low in the textile and garment industry. To date, there have been reports of only individual cases of contact dermatitis, and the major risk has been shown to be for the workers who do the dyeing operations [2, 3, 6–8]. The causes of sensitization often remain unknown, but the substances most often cited as responsible are potassium bichromate [4], antiwrinkling resins with formaldehyde base [3], antispotting agents [2], antiinflammatory agents [2], optical whiteners [9], and biocidal agents [3, 5].