Reduced frequency of nickel allergy upon oral nickel contact at an early age

From animal studies we know that oral administration of T-dependent antigens before sensitization effectively induces systemic immune unresponsiveness. Such 'oral tolerance' is persistent, dose-dependent, antigen-specific and presumably T suppressor cell-mediated. Oral tolerance induction could be an effective way to prevent undesired T cell-mediated immune functions, such as playing a role in allograft reaction, autoimmune and allergic diseases. In the present study allergic contact hypersensitivity (ACH) to nickel, currently presenting the most frequent contact allergy in man, was chosen to establish the feasibility of oral prevention of undesired T cell-mediated immunity in man. Potentially tolerizing (oral nickel contacts via orthodontic braces) as well as sensitizing (ear piercing) events were studied retrospectively in 2176 patients attending nine European patch test clinics. Patients were interviewed by means of a confidential questionnaire. The results show that ear piercing strongly favoured development of nickel ACH. More importantly, patients having had oral contacts with nickel-releasing appliances (dental braces) at an early age, but only if prior to ear piercing, showed a reduced frequency of nickel hypersensitivity. Frequencies of other hypersensitivities, in particular to fragrance, were not affected. These results support our view that induction of specific systemic immunologic tolerance by timely oral administration of antigens is feasible in man.

A comparison of expression of surface-bound immunoglobulin E on antigen-presenting cells in cutaneous tissue between patients with allergic, irritant and atopic dermatitis

The expression of surface-bound immunoglobulin E by dendritic cells within cutaneous tissue has been compared in atopic and contact dermatitis. 45 patients were recruited into 4 groups using clinical criteria and patch testing to a standard series of allergens: atopic (12 cases), allergic contact dermatitis (14 cases), irritant contact dermatitis (10 cases) and the control group (9 cases); using clinical criteria and patch testing to a standard series of allergens. Skin biopsies from each patient were analysed by the indirect immunofluorescence technique. This differentiated 3 patterns of cutaneous IgE distribution: (i) no detectable cutaneous IgE; (ii) detection of IgE solely within the dermis; (iii) detection of IgE within both epidermis and dermis. Detection of IgE within the epidermis was always associated with the presence of IgE within the dermis. In each case, IgE was surface-bound by dendritic cells. Immunoglobulin E was detected within both epidermis and dermis in skin biopsies from 8 (66.7%) atopic patients and 2 (20%) patients with irritant contact dermatitis. No other cases demonstrated IgE deposition within both the epidermis and dermis. Atopic patients were significantly more likely to have detectable IgE deposition, within both epidermis and dermis, than patients with contact dermatitis (allergic and irritant groups combined, p = 0.0011) or controls (p = 0.0049). This finding suggests that the demonstration of IgE within both epidermis and dermis supports a diagnosis of atopic dermatitis. It would therefore be of value in differentiating between atopic and contact dermatitis, where clinical diagnosis is in doubt.

The nickel content of certain commercially available metallic patch test materials and its relevance in nickel-sensitive subjects

The nickel contamination of the metallic patch test substances from 3 commercial sources was estimated by atomic absorption spectrophotometry. Contamination was generally greatest in the cobalt patch test substances. To determine whether the levels of contamination encountered were sufficient to produce a false positive patch test, 20 nickel-sensitive patients were patch tested to various concentrations of free elemental nickel in aqueous solution. The level of nickel contamination was less than that required to produce a false positive patch test in our patients, but was at a level which could produce false positive reactions in subjects highly sensitive to nickel.

Minocycline-induced pigmentation occurring in two sisters

Two sisters are described who developed facial pigmentation while on minocycline therapy for acne vulgaris. It is suggested that the possible mechanisms for this relatively uncommon complication occurring in these two patients may be due to either a genetically acquired alteration in metabolic handling of minocycline or to the ethinyloestradiol component of Dianette, which they were also receiving as treatment for their acne vulgaris. It is concluded that patients on minocycline should be regularly screened for signs of hyperpigmentation, especially if they are on other drugs which are known to accentuate pigmentation of skin.

Incidence of acne vulgaris in patients with infantile acne

A group of patients who attended dermatology clinics in Northern Ireland between 1960 and 1970 with a diagnosis of infantile acne was compared with a similar age-matched control group of 160 medical students. The severity of the acne was judged according to the form of treatment required--topical treatment, systemic antibiotics or isotretinoin. The statistical power of this study is limited but there appears to be a trend towards higher incidence and greater severity of acne vulgaris in teenage years in patients with a history of infantile acne compared to their peers.

Patch testing with the "sesquiterpene lactone mix": a marker for contact allergy to Compositae and other sesquiterpene-lactone-containing plants. A multicentre study of the EECDRG

6278 patients were patch tested with a sesquiterpene lactone mix (SL-mix) in 10 European clinics. 4011 patients were tested only with 0.1% SL-mix, 63 (approximately 1.5%) of whom were positive, with 26 (41%) of these cases being considered clinically relevant. There were no cases of active sensitization, though 5 cases of irritation were reported. 22 irritant reactions and 22 cases of active sensitization occurred when testing also with 1% and 0.33% concentrations of SL-mix. SL-mix 0.1% pet. is shown to be an important patch test and many relevant sensitizations will be missed without routine screening with such a mix. Most patients with SL-mix sensitivity presented with hand and/or face dermatitis, apparent photodermatitis or more generalised eczema.

Elevated T cell subpopulations in dental students

The absolute numbers of circulating white cells and lymphocyte subpopulations were studied in 25 final-year dental students and compared with a control group of 28 medical students. The total lymphocyte count, total T cell numbers (CD3), T helper/inducer (CD4), and T suppressor/cytotoxic (CD8) numbers were significantly elevated in the dental students as compared with the control group. There was no significant difference in the T helper/inducer to T suppressor/cytotoxic cell ratios or the circulating B cell (CD21) and natural killer cell (CD16) numbers between the study and control groups. Patch testing to mercury and mercuric compounds in both the study and control groups showed no evidence of cutaneous hypersensitivity to mercury. The reason for the observed elevations in T cell subpopulations in dental students is not clear. However, one possible explanation is the dental student's occupational exposure to mercury. Further work is underway to examine this possible relationship and it is suggested that dental personnel take adequate measures to reduce their exposure to mercury until the results of these studies are available.

Contact allergy to Bronopol

A total of 8149 patients were patch tested with the preservative Bronopol in 7 European contact clinics. The majority of patients (6507) were investigated in London. Reactivity was low, with a total of 10 irritant (0.12%) and 38 allergic reactions (0.47%). In only 17 cases (0.21%) was the patch test reaction to Bronopol considered to be of current or past clinical relevance. Concomitant sensitization to formaldehyde was present in about 1/3 of patients. Based on these figures, the present sensitization rate to Bronopol in Europe seems to be quite low, which may be related to its less frequent use as a preservative in cosmetics and medicaments in comparison to parabens or isothiazolinones.

Nickel allergy in relationship to previous oral and cutaneous nickel contact

Potential relationships between the development of nickel allergy and previous ear piercing or orthodontic treatment with nickel-containing appliances were studied in 294 patients. We found 77 (31.2%) of 247 patients with pierced ears were allergic to nickel compared to only three (6.4%) patients without pierced ears (p = 0.001), which confirms earlier suggestions that nickel allergy (as assessed by patch testing) is promoted by ear piercing. If orthodontic treatment preceded the event of ear piercing, the frequency of nickel allergy was reduced from 36% to 25%. This supports the view that oral allergenic contacts may induce immunological tolerance.

The measurement and definition of ptosis

Measurements of 242 ptotic and normal eyelids were recorded clinically and compared with algebraically derived measurements from projected 35 mm photographs. Accuracy to 1.5 mm or better was obtained in 84% of clinical as compared with photographic measurements. The following definition is suggested: ptosis is present when the upper eyelid is less than 2 mm from midpupil. Reduction of the upper field of vision to 30 degrees or less is present in 97% of eyes with ptosis so defined. Asymmetric ptosis is present in the lower of the two upper eyelids when there is 2 mm or more asymmetry between the levels of the upper eyelids, even if both eyelids are 2 mm or more from midpupil. Although ptosis is best defined in terms of the midpupil to upper lid distance, the diagnosis of ptosis rests with the examining physician based on the clinical evaluation of the patient.

Atopy in subjects with a history of nickel allergy but negative patch tests

Various markers of atopy were studied in 20 subjects with a history of nickel allergy but negative patch test reactions, and compared with 2 control groups: 13 subjects with no history of nickel allergy and negative patch tests; 11 subjects with a history of nickel allergy and positive patch tests. No significant difference in the incidence of atopy was detected in the 3 groups.

T-cell subset assay. A useful differentiating marker of atopic and seborrheic eczema in infancy?

To confirm T-cell changes previously reported in atopic eczema, to compare T-cell subset values in atopic and seborrheic infants, and to determine whether T-cell subset assay would be a useful differentiating marker between atopic and seborrheic infants, three age- and sex-matched groups of normal, seborrheic, and atopic infants were recruited. T-cell subset values, total serum IgE, and serum IgE to specific allergens (Dermatophagoides pteronyssimus, cat epithelium, dog dander, rye grass, egg white, and milk) were measured. The results showed that total and allergen-specific IgE levels were higher in atopic disease in infancy, but no statistical differences in T-cell subset values between seborrheic and atopic infants were found. T-cell subset values are therefore not a reliable differentiating marker between atopic and seborrheic eczema in infancy.

Stimulation of urinary copper excretion by trientine((R)) in nickel-sensitive patients

Trientine((R)) is not an effective drug for the treatment of intractable hand dermatitis in nickel-sensitive patients. In a controlled, double-blind study this chelator, on oral administration, failed to stimulate nickel excretion. Early morning urine samples from two groups of nine patients were analyzed by atomic absorption spectrophotometry in a stabilized Temperature Platform Furnace equipped with Zeeman background correction. Group 1 patients received placebo for 6 wk, then a 4-wk rest before crossover. Group 2 received the drug in the first period. No difference in Ni levels between the placebo period and the drug period in either group was demonstrated, nor was there any significant improvement in the hand eczema.Copper was measured in the same urine samples using the same instrumentation, but with atomization off the wall. There was a considerable increase in copper excretion during the drug treatment period. Group 1 excreted a mean 538±378 (SD) μg/L, which represented a mean increase of 787±653 % (SD). Group 2 excreted a mean 960±410 (SD) μg/L; a mean difference of 630±398 % (SD). It was concluded that the use of Trientine((R)) in subjects of normal copper status should be carefully controlled and monitored.