[Oral lichen planus, amalgam and other restorative materials]

Mucosal lesions in the oral cavity, identical to oral lichen planus (OLP), as a consequence of contact with in particular dental silver amalgam may be due to an allergic reaction to mercury or, possibly, a toxic effect on the oral mucosa. Substitution of amalgam preferably by gold--unless sensitisation to gold exists--often results in remission, which sustains a pathogenic role of amalgam in OLP. Substitution of amalgam should be considered if the mucosal lesions correspond topographically to the restorations and epicutaneous patch testing results in a positive reaction on mercury.

Expression of E-cadherin, alpha- & beta-catenin, and CD44V6 and the subcellular localization of E-cadherin and CD44V6 in normal epidermis and basal cell carcinoma

Basal cell carcinoma (BCC) of the skin is a locally invasive, rarely metastasizing epithelial tumor. In the current study, the expression of E-cadherin, alpha- and beta-catenin and CD44V6 in normal epidermis and on BCC cells were investigated. A significantly reduced expression of alpha-catenin and CD44V6 and a slightly reduced expression of E-cadherin on BCC cells were observed compared with the overlying epidermis. Immunoelectron microscopy was used to investigate whether the decreased expression of E-cadherin and CD44V6 was due to either an absence or downregulation of specific membrane structures or due to an overall downregulation of these adhesion molecules in all membrane structures in BCC. E-cadherin and CD44V6 were expressed in adherens junctions, desmosomes, and complex interdigitating membrane structures both in normal epidermis and in BCC. A quantitative analysis showed that only a percentage of desmosomes was stained. In addition, the effect of pro-inflammatory cytokines, such as interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha), was investigated in biopsy specimens of normal skin and BCC, using a biopsy culture system and immunohistochemistry. The expression of E-cadherin and CD44V6 was not significantly decreased after culturing BCC or normal skin biopsy specimens for 48 hours with or without recombinant human (rHu)IFN-gamma or rHuTNF-alpha. It may be concluded that the decreased expression of both E-cadherin and CD44V6, observed in light microscopy, was not attributable to the absence of specific specialized structures in BCC and most likely also not caused by downregulation by local cytokines, but rather by generic downregulation of both of these adhesion molecules during malignant transformation.

[Cutaneous and mucosal reactions to dental materials]

The concentration of substances released by dental materials is usually too low to cause systemic-toxic effects, but there is the potential to induce dermatoses in especially dentists as well as mucositis in mainly dental patients. The cytotoxic irritative and allergic diseases are successively described categorized according to their pathogenesis. The identification of the diseases, which often have a similar appearance, depends on history-taking and patch testing. Non-dental sensitization is of diagnostic importance.

Prevalence of natural rubber latex allergy (type I and type IV) in laboratory workers in The Netherlands

The objective of the study was to study the prevalence of Type IV and Type I allergy to natural rubber latex (NRL) in a population at risk in the Netherlands. Laboratory workers regularly using gloves were invited to complete a questionnaire and to be tested. We performed patch tests with standard contact allergens, rubber additives, glove powder and pieces of 4 gloves; prick tests with inhalant allergens, glove extracts, glove powder and fruit extracts; and RASTs. Glove-related hand dermatitis was reported in 36.9% of the individuals interviewed. A positive patch test result for rubber additives was seen in only 6.6%. Glove-related urticaria, rhinoconjunctivitis and/or asthma were reported in 24.6% of all cases. Confirmation of an IgE-mediated reaction was achieved in 8.3% by prick test with glove extracts and 5.0% by RAST. No reaction to glove powder was noticed in patch testing or in prick testing. A high prevalence rate of glove-related symptoms and NRL Type I allergy was found in laboratory workers exposed to rubber gloves. Surprisingly, there was no co-existence of Type I and Type IV allergy in this population.

Expression of interferon-gamma receptors and interferon-gamma-induced up-regulation of intercellular adhesion molecule-1 in basal cell carcinoma; decreased expression of IFN-gamma R and shedding of ICAM-1 as a means to escape immune surveillance

The peritumoural inflammatory infiltrate in basal cell carcinoma (BCC) of the skin consists mainly of T lymphocytes which hardly invade the tumour nests. The absence of intercellular adhesion molecule-1 (ICAM-1) on BCC cells may explain the lack of tumour-infiltrating cells and the lack of an active cell-mediated immune response in this tumour. In this study, the induction of ICAM-1 was investigated in BCC biopsies using recombinant human interferon-gamma (rHuIFN-gamma). The expression of interferon-gamma receptors (IFN-gamma R) in the biopsies was also investigated. The results showed that BCC cells expressed ICAM-1 after incubation with rHuIFN-gamma, but to a lesser degree than normal epidermal cells. The levels of shed ICAM-1 were significantly increased in the culture supernatants of tumour biopsies compared with those from normal skin biopsies, after culturing in the presence of rHuIFN-gamma. The expression of IFN-gamma R was significantly decreased on the tumour cells compared with the overlying epidermis. The decreased expression of IFN-gamma R on the tumour cells and the shedding of ICAM-1 into the peritumoural stroma may be a plausible mechanism by which the tumour cells are protected against an active cell-mediated immune response.

Delayed-type hypersensitivity to contact allergens in psoriasis. A clinical evaluation

The possibility for patch testing procedures to detect contact allergy was examined in 85 hospitalized patients with forms of psoriasis. Exclusion criteria were active lesions on the back, the use of strong topical corticosteroids, methotrexate, cyclosporin and UV therapy. After screening, a group of 47 patients with different forms of psoriasis were selected for patch testing. Personal history, including topical treatment, occupation and domestic circumstances, were reasons to extend the standard series of allergens. Tars, nickel sulfate, perfume and balsam of Peru scored high. The overall positive rate was 68%. This is higher than that observed in earlier studies. The unexpected results are discussed in the light of the possible mechanism of action.

Allergy to carbamazepine: parallel in vivo and in vitro detection

PURPOSE

Five to 20% of patients discontinue antiepileptic drug (AED) therapy because of adverse reactions. Careful reintroduction, however, may be considered if true drug allergy can be ruled out. Definitive assessment of such immunologically mediated reactions requires demonstration of either specific antibodies or sensitized lymphocytes.

METHODS

We investigated whether skin patch tests (PTs) and in vitro lymphocyte proliferation assays (LPAs) were suitable for detection of allergy to carbamazepine (CBZ) and the possibly cross-reactive oxcarbazepine (OCBZ). Data of 65 patients displaying a wide range of possibly allergic side effects to CBZ were available for analysis. Data of CBZ users without any side effects and healthy volunteers served as controls. Both PTs and LPAs were done with CBZ, OCBZ and three metabolites [CBZ-10,11-epoxide (CBZ-E), 10-monohydroxy-CBZ (MHD), and 10,11-dihydroxy-CBZ (DIOL)].

RESULTS

Positive PTs with CBZ were seen in 20% and with OCBZ in 14% of the patients. Positive LPA results with CBZ and OCBZ, respectively, were found in 40 and 19%. Both tests were positive in 14 and 7% of the patients. Cross-reactivity to OCBZ was seen in -40% of CBZ-reactive patients in both PTs and LPAs.

CONCLUSION

These data illustrate the additional value of LPAs in the detection of CBZ allergy while showing that a major part of side effects to CBZ and OCBZ is not immunologically mediated, according to PTs and LPAs.

Somatostatin receptor scintigraphy in cutaneous malignant lymphomas

BACKGROUND

Lymphoid cells may express somatostatin receptors (SS-Rs) on their cell surface. Therefore radiolabeled somatostatin analogues may be used to visualize SS-R-positive lymphoid neoplasms in vivo. Exact staging is the basis for treatment decisions in cutaneous malignant lymphoma. We considered the possibility that SS-R scintigraphy might offer a clinically useful method of diagnostic imaging in patients with cutaneous malignant lymphoma.

OBJECTIVE

We evaluated SS-R scintigraphy in comparison with conventional staging methods in the staging of cutaneous malignant lymphoma.

METHODS

We conducted a prospective study in 14 consecutive patients with histologically proven cutaneous malignant lymphoma. SS-R scintigraphy was compared with physical, radiologic, and bone marrow examinations. Lymph node excisions were performed in patients with palpable lymph nodes.

RESULTS

SS-R scintigraphy was positive in the lymph nodes in all four patients with malignant lymph node infiltration and negative in the three patients with dermatopathic lymphadenopathy. In two patients, previously unsuspected lymphoma localizations were visualized by SS-R scintigraphy. In only three patients all skin lesions were visualized by SS-R scintigraphy; these three patients had not been treated with topical corticosteroids. SS-R scintigraphy failed to detect an adrenal mass in one patient and bone marrow infiltration in two patients.

CONCLUSION

SS-R scintigraphy may help distinguish dermatopathic lymphadenopathy from malignant lymph node infiltration in patients with cutaneous malignant lymphoma.

Increased expression of interleukin-4 receptors on psoriatic epidermal cells

Abnormal keratinocyte proliferation and differentiation, the main characteristics of psoriasis, may be induced and maintained by cytokines produced by activated resident and recruited inflammatory cells in lesional skin. As the epidermal cytokine profile is clearly altered in psoriasis and because increased expression of interleukin-4 receptor (IL-4R) has been reported in some epithelial proliferative diseases, we investigated the expression of IL-4R on psoriatic epidermal cells (ECs). The expression of IL-4R on freshly isolated ECs from healthy skin and untreated psoriatic lesions was studied by immunostaining using an IL-4R-specific antibody and by examining their capacity to bind biotinylated recombinant human IL-4 using flow cytometry. The number of IL-4R+ ECs and the number of binding sites per cell were significantly increased on psoriatic ECs as compared with healthy control ECs. Immunostaining confirmed these results, whereby staining was mainly observed in the lower epidermal layers. In addition, an increased IL-4R mRNA expression was also observed in psoriatic epidermis using a digoxigenin-labeled IL-4R RNA probe. In short-term in vitro cultures, lipopolysaccharide/phorbol-myristate-acetate-stimulated and unstimulated psoriatic ECs did not produce any immunoreactive IL-4. The results of this study together with the reported increased expression of IL-4R in epithelial neoplasias suggest an association between overexpression of IL-4R and abnormal keratinocyte activation and proliferation.

Methyldibromoglutaronitrile is an important contact allergen in The Netherlands

From 15 May to 15 December 1994, 2943 patients suspected of having contact dermatitis (1955 women, 988 men) were patch tested with methyldibromoglutaronitrile 0.3%, 0.1% and 0.05% pet. 119 patients (4.0%; women 4.1%, men 3.8%) proved to be allergic. 71% of the reactions were considered to be relevant. In 2/3 of the patients, causative products were cosmetics, in 1/3 moistened toilet tissues. Testing with methyldibromoglutaronitrile at lower concentrations (0.05% and 0.1%) and with commercial allergens (Euxyl K 400 and methyldibromoglutaronitrile, both containing methyldibromoglutaronitrile 0.1%), resulted in a number of false-negative reactions. All preservatives in the European standard series had lower scores than the 4% positive reactions to methyldibromoglutaronitrile (formaldehyde 2.0%, MCI/MI (Kathon CG) 3.2%, parabens 1.0%, quaternium-15 1.3%). It is concluded that methyldibromoglutaronitrile (present in the commercial preservative Euxyl K 400) is an important contact allergen in the Netherlands in cosmetics and moistened toilet tissues. It should be added to cosmetics series and to proctological series. The optimal test concentration is unknow, but may be 0.3% pet. The concentration of 0.1% methyldibromoglutaronitrile in the currently available commercial allergens appears to be too low, resulting in a number of false-negative reactions.

Adhesion molecules and IL-1 costimulate T lymphocytes in the autologous MECLR in psoriasis

Membrane molecules such as CD36 (OKM5), intercellular adhesion molecule-1 (ICAM-1, CD54), gamma interferon-induced protein 10 (gamma-IP10) and IL-1 are induced and/or upregulated in psoriatic epidermis. These molecules have important accessory, trafficking or signalling functions in the immune system and also play a role in the pathophysiology of psoriasis. The relevance of adhesion molecules, CD36 and epidermal IL-1 in psoriasis was studied in vitro in the autologous mixed epidermal cell - T lymphocyte reaction (MECLR). Their level of expression was quantitated in epidermal cell suspensions (ECS) from patients with psoriasis and their function was assessed by blocking with specific mAbs and antisera or by depleting CD36+ cells from the ECS prior to the MECLR. ECS from psoriatic lesions contained increased numbers of CD36+ (23 +/- 12%), ICAM-1(+) (31 +/- 14%) and IL-1(+) (57 +/- 21%) cells. The autologous MECLR was inhibited in samples from all patients by mAb to CD2 (LFA-2), CD11a (LFA-1alpha), CD18 (LFA-1beta), ICAM-1, CD58 (LFA-3) and an antiserum to IL-1beta. Thus, adhesion molecules facilitate inflammation in psoriasis not only via adhesion and recruitment of T lymphocyte in psoriatic lesions, but also via activation of T cells. Furthermore CD36 molecules on psoriatic epidermal cells do not costimulate autologous T lymphocytes in psoriasis. The observed costimulatory function of IL-1beta in the MECLR emphasizes its relevance in psoriasis.

Expression of cytokeratin 8 in basal cell carcinoma: a comparative immunohistochemical and immunoelectron microscopy study

The comparative study reported here was undertaken in order to resolve the discrepancies in the detection of cytokeratin (Ck) 8 reported in previous studies. The expression of Ck 8 was compared in 6 basal cell carcinomas (BCCs) using immunohistochemical and immunoelectron microscopic techniques and a panel of 4 different commercially available monoclonal antibodies (MoAbs). The results of this comparative study demonstrated not only that the consistent expression of Ck 8 using one of the MoAbs in immunohistochemistry was confirmed by immunoelectron microscopy, but that the inconsistent expression of Ck 8 observed using two other MoAbs was also confirmed. One of the MoAbs did not show any staining at all. The inability of this MoAb to detect the expression of Ck 8 using either of the techniques also indicated that this MoAb may be directed against an epitope of Ck8 that is not detectable in BCC in situ.

Effects of cyclosporine on cytokines and cytokine receptors in psoriasis

BACKGROUND

Oral cyclosporine is effective in the treatment of recalcitrant psoriasis. However, the precise mechanism(s) are not fully understood. A possible mode of action may be via down-modulation of proinflammatory cytokines that are increased in psoriatic lesions.

OBJECTIVE

This study was designed to monitor the effects of cyclosporine treatment on the expression of cytokines, cytokine receptors, and other markers of inflammation in psoriatic skin.

METHODS

Ten patients with recalcitrant psoriasis were treated with cyclosporine. The in vivo effects of cyclosporine on cytokines and their receptors were studied by the use of cryostat-cut sections and a panel of antibodies. The in vitro effects were studied with flow cytometry of epidermal cell suspensions prepared from psoriatic lesions and control skin.

RESULTS

Clinical improvement was noted in all patients after 2 weeks of cyclosporine treatment. The expression of interleukin-1 beta, interleukin-8, CD25(IL-2R), CD36 and E-selectin were significantly decreased, whereas the number of tumor necrosis factor-receptor-positive epidermal cells was significantly increased in psoriatic lesions.

CONCLUSION

Clinical improvement of psoriasis with cyclosporine treatment is accompanied by down modulation of proinflammatory epidermal cytokines and decreased dermal inflammation. Thus besides suppressing cytokine production by the inflammatory infiltrate, the beneficial effect of cyclosporine in psoriasis also depends on the inhibition of the epidermal cytokine network.

In vivo cytokine profiles in allergic and irritant contact dermatitis

Local cytokine profiles in skin biopsies from allergic and irritant patch test reactions were determined by in vivo immunohistochemistry to differentiate between these 2 clinically identical afflictions especially at the same time of final reading in diagnostic patch testing. Biopsies were taken from established allergic persons after specific allergic patch tests to epoxy resin (1%), and formaldehyde (1%) and from non-allergic individuals with irritant patch tests to sodium lauryl sulfate (10%) and formaldehyde (8%). At 72 h after application of the agents, significantly enhanced frequencies of dermal infiltrating cells, producing IL-alpha, IL-2, and IFN-gamma per 100 infiltrating cells in the dermis, were observed in allergic as well as irritant test patch reactions, as compared to normal skin. Significantly higher frequencies of IL-1alpha producing cells were observed in biopsies from epoxy resin (1%) allergen-affected and formaldehyde (8%) irritant affected skin. The allergic and irritant patch test reactions showed similar levels of expression of the Th1 cytokines IL-2 and IFN-gamma in the dermis, confirmed by probe based detection of IL-2 mRNA and IFN-gamma mRNA. In conclusion, the described similarity shows that allergens and irritants can induce the same profile of IL-1alpha, TNF-alpha, IL-2, and IFN-gamma production, resulting in the near impossibility of discriminating between allergic and irritant contact dermatitis at the time of patch test reading.

Migration of human antigen-presenting cells in a human skin graft onto nude mice model after contact sensitization

Fluorescent contact chemical allergens provoke sensitization after application on both syngeneic and allogeneic skin grafts in mice. We attempted to determine whether the functional activity in a contact sensitization response of human skin graft was affected at the level of antigen uptake and migration. After xenogeneic skin transplantation, we examined the effect of topical exposure of the graft to rhodamine B isothiocyanate (RITC). This paper describes the migration of RITC-carrying cells and human major histocompatibility complex (MHC) class II DR (HLA-DR)+ cells, from the graft to mouse draining lymph nodes. As demonstrated by immunohistochemistry, grafting resulted in a time-dependent decrease of human HLA-DR+ and CD1a+ cells, and an increase of mouse MHC class II (Ia)+ cells within the graft. Application of RITC on a 3-week-old human skin graft showed optimal migration capability compared to 6- or 9-week-old grafts. In addition, the time-dependent increase of frequencies of RITC+ and HLA-DR+ cells in the draining lymph nodes, and the time-dependent decrease of HLA-DR+ cells in the 3-week-old human skin graft, were concurrent. Supporting these data, human cytokine interleukin-1 alpha (IL-1 alpha), IL-1 beta and tumour necrosis factor-alpha (TNF-alpha), analysis in situ revealed that cytokine production by keratinocytes, a property associated with dendritic cell migration, was preserved in the human skin graft. Thus, like dendritic cells in contact sensitization in allografted skin, dendritic cells from human xenografted skin onto nude mice are capable of migration to mouse draining lymph nodes after allergen application. Induction of contact hypersensitivity is possible in a human skin graft onto nude mice model, although the use of this ex vivo model to analyze contact sensitivity is probably limited to 3 weeks after transplantation.

Hyposensitization in nickel allergic contact dermatitis: clinical and immunologic monitoring

BACKGROUND

In allergic contact dermatitis (ACD) previously sensitized T cells cause skin damage. If an ubiquitous allergen such as nickel is involved, no effective treatment is available. Down-regulation of this allergic response has been described after antigen presentation in the absence of adequate costimulatory signals. UV exposure can enhance such hyposensitization.

OBJECTIVE

The aim of this study was to establish the capability of a hyposensitization procedure to induce antigen-specific tolerance.

METHODS

Twenty-one patients with nickel ACD were randomly assigned to either a hyposensitized or control group. A schedule consisting of UVB treatment and subcutaneous nickel sulfate administration (hyposensitization) or UVB only (control) was applied. During the ensuing 2 years, several clinical and immunologic features were monitored.

RESULTS

During UVB treatment we observed a significant clinical improvement in both groups that persisted in the hyposensitized group. Except for increased slope variances of specific lymphocyte proliferation in time, no clear changes were seen in the immunologic findings.

CONCLUSION

Despite significant clinical improvement induced by UVB, hyposensitization did not induce significant changes in the immunologic findings in patients with nickel ACD.

Cutaneous adverse reactions after intra-articular injection of triamcinolone acetonide

A patient is described with a disseminated morbilliform and partially persistent urticarial dermatitis following intra-articular injections of triamcinolone acetonide. A delayed-type hypersensitivity to triamcinolone acetonide was observed after patch and intradermal testing. However, an immediate-type hypersensitivity to this drug was not observed. A delayed-type sensitization to betamethasone, dexamethasone and prednisolone, but not to hydrocortisone was also observed after patch testing. Intradermal tests with these representatives of corticosteroids were all negative. Although little is known yet about the relationship between immediate and delayed-type hypersensitivity and the side-effects of oral use of corticosteroids, the absence of positive skin tests to corticosteroids other than triamcinolone acetonide may indicate a safe use of these drugs orally or via injection.

Sensitization to thimerosal (Merthiolate) is still present today

The results on thimerosal (Merthiolate) hypersensitivity of a retrospective study, together with the relevant data on thimerosal hypersensitivity referred to in the literature up to 1993, are presented. Positive patch test reactions to thimerosal (0.1% pet.) were observed in 32 (1.3%) of 2461 adult patients with suspected contact allergy examined in the period 1987-1992. 20 (0.8%) patients had a solitary positive patch test to thimerosal. The observed incidence is low. Clinical symptoms related to thimerosal hypersensitivity were observed in only 3 patients. The collected results are discussed with emphasis on the clinical implications of sensitization to thimerosal. It appears that a positive patch test to thimerosal is frequently clinically irrelevant.

Cyclosporin in atopic dermatitis: a multicentre placebo-controlled study

The efficacy of cyclosporin (Sandimmun) given in a daily dose of 5 mg/kg for 6 weeks in severe atopic dermatitis was confirmed in this double-blind, placebo-controlled, short-term study. Of the 46 patients included in the study, 23 were randomized to receive cyclosporin and 23 to receive placebo. Four of the 23 patients (17%) on cyclosporin, and 14 of the 23 patients (61%) who received placebo, discontinued the trial because of inefficacy. All patients who discontinued the trial were assessed following the principle of 'intention to treat'. Compared with the baseline, the mean scores for disease severity [6-area, total body severity assessment (TBSA)] improved by 55%, and the mean scores for extent of disease [rule-of-nines area assessment (RoNAA)] improved by 40%, in patients treated with cyclosporin. Nine of the patients who received cyclosporin and completed the study (n = 14) had an individual reduction of disease severity (TBSA) of 75% or more, and in three patients this reduction was nearly 100%. In the placebo group, a mean worsening of disease severity (4%) and of extent of the disease (25%), compared with the baseline, was observed at week 6. Patients' and investigators' mean scores for the overall efficacy were similar, and showed a statistically significant difference in favour of cyclosporin. Two patients on cyclosporin developed hypertension during therapy, and one of these withdrew from the study. At the end of the trial, no statistically significant differences in the systolic or diastolic blood pressures were observed between the two groups. In the cyclosporin group, the increases in the values of serum creatinine and bilirubin at week 6, compared with the respective values at the baseline, were statistically significantly different from those in the placebo group, but all values normalized in the post-treatment period. Cyclosporin can be a safe and very effective treatment in episodes of severe atopic dermatitis, provided that the recommended guidelines for its administration are strictly observed.

Oral manifestations of gold allergy

BACKGROUND

Sensitization to gold in a large group of patients suspected of clinical allergy to this metal has not been reported.

OBJECTIVE

Two hundred patients with symptoms of persistent oral mucosal or cutaneous lesions that were possibly related to allergy to constituents of gold alloys or gold jewelry were patch tested to determine the frequency of sensitization.

METHODS

Patch testing was performed with the European standard series and a series of dental materials including three different salts of gold. A persistent papular reaction to gold-(tri)chloride was considered a positive reaction.

RESULTS

In 17 patients (8.5%, all women, mean age 50.2 years) persistent papular patch test reactions to both 0.5% and 1.0% gold(tri)chloride were observed. In five of seven patients with oral lichen planus (OLP) and in one of six patients with the burning mouth syndrome, gold in the dentures was replaced. Particularly in patients with OLP, a significant but variable improvement was observed. In all cases in which gold was replaced and improvement occurred, the patients were sensitized to 0.5% gold(tri)chloride. One patient with allergic contact stomatitis and one patient with allergic contact dermatitis healed completely after gold had been replaced.

CONCLUSION

Sensitization to gold should be considered as a possible cause of allergic contact dermatitis and allergic contact stomatitis as well as a pathogenic or triggering factor in OLP.

[Amalgam. VI. Allergy to mercury in dental materials; oral and systemic reactions]

Allergy for mercury in dental alloys can be responsible for the induction of allergic contact stomatitis. Evidence is also available for a role of mercury sensitization in the pathogenicity of oral lichen planus in particular. Aspects related to the development of allergic processes in the oral cavity are summarized. Allergy for mercury as the cause of oral mucosal reactions is rather rare in spite of the frequent use in dental amalgam, but probably underestimation of the incidence should be considered. Recent views with respect to the role of mercury as allergen in allergic contact stomatitis, oral lichen planus, the so-called Burning mouth syndrome and in systemic allergic reactions are summarized. Immunologic aspects in the pathogenesis are briefly discussed. Especially in cases in which the site or oral lesions is opposite to the dental alloy it is important to establish sensitization for mercury by use of epicutaneous path testing. When a positive test to mercury is obtained replacement of mercury containing alloys should be considered.

Frequency of false-negative reactions to the fragrance mix

To estimate the frequency of false-negative reactions to the fragrance mix, the 8 constituents of the mix in concentrations of 5% (2% for cinnamic aldehyde) were added to the European standard series for routine testing. Patients with positive reactions to individual ingredients in the absence of a reaction to the mix were retested with serial dilutions. In a 4-month period, 677 patients were tested. 61 (9%) reacted to the mix and to 1 or more of the ingredients. 4 patients (0.6% of all patients tested and 6.2% of the patients allergic to fragrances) had false-negative reactions to the mix. They were allergic to cinnamic alcohol, geraniol, isoeugenol and oak moss (1 reaction each), in the absence of a reaction to the fragrance mix. It is concluded that the currently used concentration of the mix (8 x 1%) not infrequently results in false-negative reactions, and that further research should be done to overcome this problem.

Secondary erythermalgia in systemic lupus erythematosus; [comment]

Secondary erythermalgia, as a symptom of an underlying illness, is characterized by burning pain in the extremities together with local erythema and warmth. The onset and clinical symptomatology of secondary erythermalgia in a woman with a 20 year history of systemic lupus erythematosus (SLE) is described. Histopathologic examination of affected skin areas revealed an inflammatory process compatible with vasculitis. These findings completely differ from the histopathology in erythromelalgia and in primary erythermalgia. The erythermalgic symptoms completely resolved by treatment with prednisone. We conclude that secondary erythermalgia in SLE in our patient was associated with cutaneous vasculitis.

Cyclosporine in atopic dermatitis. Modulation in the expression of immunologic markers in lesional skin

BACKGROUND

In previous studies, oral cyclosporine was highly effective in the treatment of patients with severe atopic dermatitis. In this study seven patients with severe and therapy-resistant atopic dermatitis underwent therapy with cyclosporine, 5 mg/kg/day, for 6 weeks.

OBJECTIVE

The effect of cyclosporine on the expression of cytokines, which probably play a role in this disease, was examined.

METHODS

The study was performed with a panel of antibodies as markers of inflammatory cells, adhesion molecules, and cytokines (interferon-gamma [IFN-gamma], tumor necrosis factor-alpha [TNF-alpha] and interleukins 1 alpha, 1 beta, and 8 [IL-1 alpha, IL-1 beta, and IL-8, respectively]). They were visualized by indirect immunoperoxidase techniques.

RESULTS

After 2 weeks of cyclosporine therapy, a reduction of 60% in the disease (severity and extent) was observed. This reduction was 89% after 4 weeks and 90% after 6 weeks of therapy. Results of indirect immunoperoxidase stains performed on lesional skin sections after 2 weeks of treatment showed statistically significant reduced numbers of CD14+, CD25 (IL-2R+) and IL-8+ inflammatory cells in the dermis and CD36(OKM5)+ cells in both the epidermis and dermis. The number of cells expressing IFN-gamma and TNF-alpha, assumed to be the products of the helper T-cell (TH)1 subset, was unaltered despite the impressive clinical benefit observed. Keratinocytes in lesional atopic skin did not express intercellular adhesion molecule type 1 (ICAM-1). The expression of the adhesion molecules ICAM-1, lymphocyte function-associated (LFA) type 1, and LFA-3 on inflammatory cells also remained unaffected by cyclosporine treatment.

CONCLUSION

A statistically significant reduction in the number of activated T cells and in the number of cells expressing the IL-2 receptor (CD25) paralleled a marked improvement in the disease and supports the view that atopic dermatitis is based on a T-cell-mediated immune inflammation.

Sensitization to azo dyes: negative patch tests to yellow and red azo dyes in printed paper

An over 2 x fold increase in para-aminoazobenzene allergy was observed in patients with allergic contact dermatitis during the years 1990-1991. Presuming that an increase in colour-printed newspapers might be a new unrecognized source of clinical allergy to azo dyes, patch tests were performed in 32 patients with an established p-aminoazobenzene allergy using a series of important azo dyes used in offset printing ink (Pigment Yellow 12, Pigment Yellow 13, Pigment Red 53, Pigment Red 57), as well as with dye-containing inks and specimens of colour-printed newspaper containing these azo dyes. In 25 out of the 32 patients (78%), positive patch tests were seen to textile azo dyes, in particular to Disperse Orange 3 (24 patients). In none of the 32 patients were reactions observed to the azo dyes used in printing ink, to the inks used or to the colour-printed paper specimens, indicating that these products were apparently not a cause of contact dermatitis in our group of patients with azo dye sensitization.

Burning mouth syndrome: a possible etiologic role for local contact hypersensitivity

BACKGROUND

The pathogenesis of the burning mouth syndrome (BMS) is not yet understood. Apart from psychologic factors, several etiologic "somatic" factors have been reported.

OBJECTIVE

In 22 patients (19 women, 3 men, mean age 56 years) classified with BMS, clinical and laboratory investigations were performed, with particular emphasis on the role of contact hypersensitivity. Twenty of the 22 patients wore a complete or partial denture.

METHODS

Besides clinical and laboratory investigations patch testing was performed with a standard routine series and a standardized denture-dental (acrylate and metal) series.

RESULTS

Folate, iron, pyridoxine deficiency, and Candida infections were found, but correction of the deficiency or treatment of the infection was of no benefit. Contact allergy to allergens used in the production of acrylate-based dentures was observed in six (27%) of the cases (all wore a denture); positive reactions were seen to N,N,-dimethyl-4-toluidine (3 cases), to 4-tolyldiethanolamine (2 cases), to benzoylperoxide (2 cases), and to oligotriacrylate (1 case). In six cases (27%) a possible relevant sensitization was seen to dental metals and in particular to gold chloride (four cases).

CONCLUSION

The possible role of local hypersensitivity reactions to denture or dental components as etiologic factors in BMS must be considered.

Differential role of lymphocyte function-associated antigens in the activation of nickel-specific peripheral blood T lymphocytes

The possible role(s) of the adhesion molecules LFA-1 alpha (CD11a), LFA-1 beta(CD18), ICAM-1 (CD54), CD2 (T11, LFA-2), and LFA-3 (CD58) in the in vitro activation of nickel-specific peripheral blood (PB) T lymphocytes was studied. For this purpose, monoclonal antibodies (MoAb) to these markers were used. Both LFA-2 and LFA-3 appeared to be consistently involved, whereas LFA-1 was inconsistently involved. In studies using antigen-presenting cells (APC) isolated from peripheral blood to present nickel, anti-LFA-1 alpha and/or LFA-1 beta MoAb partially inhibited the in vitro activation of nickel-specific T lymphocytes in nine of 42 patients allergic to nickel. In the other 33 patients variable results, ranging from a slight increase or inhibition of proliferation to no inhibition at all, was observed, in particular when different anti-LFA-1 alpha MoAb were added to the cultures. In those patients who showed no inhibition when anti-LFA-1 (alpha and beta) MoAb were added, no inhibition was also observed when a mixture of anti-LFA-1 (alpha and beta) and ICAM-1 MoAb were added to the cultures. Similar results were also obtained using epidermal APC. In control experiments the various anti-LFA-1 (alpha and beta) MoAb effectively inhibited the tetanus toxoid and Con-A induced T-lymphocyte proliferation as well as the spontaneous aggregation of the JY cell line. Anti-CD2 and anti-LFA-3 MoAb strongly inhibited the proliferative responses of nickel-specific peripheral blood T lymphocytes from all 42 patients. These results indicated that the receptor-ligand interaction between CD2 and LFA-3 is essential for in vitro activation of nickel-specific peripheral blood T lymphocytes. This activation, however, does not regularly involve LFA-1 molecules on T lymphocytes. The involvement of LFA-1 in the activation of nickel-specific T lymphocytes correlated positively with high patch test scores to nickel and the disease activity in contact dermatitis patients.

The autologous mixed epidermal cell-T lymphocyte reaction is elevated in psoriasis: a crucial role for epidermal HLA-DR+/CD1a- antigen-presenting cells

The objective of this study was to determine whether epidermal cells (EC) from psoriasis lesions and uninvolved skin could stimulate autologous T lymphocytes in the in vitro autologous mixed epidermal cell-T lymphocyte reaction (autologous MECLR). The functional role of antigen-presenting cell (APC) subsets was concurrently determined in this reaction. Mononuclear cells and purified T lymphocytes from peripheral blood of psoriasis patients showed a clear proliferative response to autologous unpurified epidermal cells from involved as well as uninvolved skin. The autologous mixed leukocyte reaction (MLR) was not elevated in psoriasis patients. In healthy controls and contact allergy patients, T-lymphocyte proliferation was not observed either in the autologous MECLR or in the autologous MLR. The level of proliferation in the autologous MECLR from psoriasis patients correlated to the number of epidermal cells that were added. To exclude the possibility that the observed proliferation in the autologous MECLR in psoriasis was due to the presence of epidermal T lymphocytes that were being stimulated and expanded in vitro, the stimulator EC were gamma irradiated (30 Gy) in some experiments. Preincubation of EC with cyclosporin A (CsA) significantly inhibited the autologous MECLR. The CsA-induced inhibition could be neutralized by the addition of fresh untreated EC to these cultures. This indicated that one of the modes of action of CsA in resolving psoriasis is, as some investigators have already shown, via inhibition of epidermal accessory cell function. In the autologous MECLR, APC from psoriasis skin could initiate this reaction, whereas APC from peripheral blood could not. This occurred in an MHC class II restricted fashion. Depletion experiments showed that Langerhans cells (HLA-DR+/CD1a+) were not the principal stimulators of autologous T lymphocytes in the MECLR. These results indicated that mainly HLA-DR+/CD1a- epidermal cells from psoriasis patients could stimulate autologous peripheral blood T lymphocytes in an MHC class II-restricted fashion.

Bullous pemphigoid in children. Report of three cases with special emphasis on therapy

Three children aged 4 months, 7 years, and 12 years, had bullous pemphigoid (BP). Two children suffered from disseminated BP and one (12 years) from vulvar localized BP. This last form has been described only once before in a girl. The various forms of pemphigoid in childhood are rare and reported in only about 40 instances. Bullous pemphigoid in childhood does not differ clearly from the adult counterpart, although lesions of the mucous membranes seem more common in childhood.