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Allergic contact dermatitis due to guava tea
Abstract
Keywords:allergic contact dermatitis;atopic eczema;medicaments;herbal remedies;guava;Psidium guajava;tannic acid;tannins;45 kD protein
... Recent research has suggested its insertion into the group of food allergens [26]. Among the aforementioned fruits, bananas and avocados are classically related to cross allergy with latex [13], while there are reports in the literature of contact dermatitis with guava [27], although with no solid references to food allergy. ...
Introduction
Although the prevalence of allergic diseases, including food allergies, has increased over recent decades, relevant information on this topic is still lacking, particularly in younger children living in small cities.
Objective
To investigate the prevalence of reported food allergies in preschoolers in Limoeiro/Pernambuco, Brazil.
Methods
This was a cross-sectional study with preschoolers. Parents/guardians of all preschoolers enrolled at municipal schools between March and June 2019 (total of 619) were invited to complete a screening questionnaire (total of 619). Another 151 questionnaires were applied on the streets of the town. For positive responses, a second, more detailed and validated questionnaire was completed.
Results
A total of 412 questionnaires were returned, of which, 47 presented a positive response to food allergies and only 29 (7.04%) identified a particular food. The most frequently reported food items were shrimp, mollusks, pork, fruit and milk. Of the 29 who identified foods, 22 responded to the detailed questionnaire, resulting in only 4 (0.97%) positive responses. Of these, two were later discarded through clinical examinations and an open oral provocation test, resulting in a final prevalence of 0.48% of confirmed food allergies.
Conclusion
The prevalence of reported food allergies was lower than that described in previous studies. The most commonly mentioned foods were shrimp, mollusks and pork, with more reports of multiple food allergies, even in children who had never been previously exposed to these possible allergens, which highlights the relevance of perception in reported food allergy studies.
... Obi and colleagues described a case of ACD from tannins in guava tea. 13 Tannins were reported to cause ACD in two patients with perianal eczema applying a topical haemorrhoidal cream containing tannin 14 and in a patient with hand eczema who applied synthetic tannin (Tannosynt liquid). 15 The allergens in tannins have not been clearly defined. ...
We report a case of a 50-year-old lady with allergic contact dermatitis to para-phenylenediamine, who in her quest to find a substitute hair dye, subsequently reacted to a number of plant-based hair dyes, including pure henna, black tea and indigo powder respectively. While these substances all contain tannins, testing to possible constituents tannic acid and gallic acid was negative.
Despite continuous improvement of techniques for the evaluation of the allergenic potential of a substance before it is introduced to the market, despite strict legislative regulations where and how to use dangerous substances and despite refined surveillance methods, the number of literature reports on newly observed contact allergens is still high. New allergens and new areas of employment demand the continuous search for possibilities of exposure. In this paper, reports from the allergological literature of the past 3 years are summarized. "New" allergens, but also new applications, new terms, altered behavioral patterns, occupational allergens, changes in the standard series, changed marketing methods as well as altered indications for patch testing will be mentioned. This article shall document that the search for trigger factors of contact allergy necessitates continuous education regarding the relevant literature, a fair amount of scientific curiosity and a dedicated patch test clinic.
Guava (Psidium guajava Linn.) commonly known for its food and nutritional values throughout the world. The medicinal properties of guava fruit, leaf and other parts of the plant are also well known in traditional system of medicine. Since, each part of guava tree possesses economic value; it is grown on commercial scale. Guava plant is considerable process has been achieved regarding the biological activity and medicinal application of guava and the fruit considered as poor man apple of tropics. The guava plant parts are used for the treatment of various disease and important medicinal values. In the present review, nutritional value of guava fruit and medicinal properties its various parts have beesn discussed to provide collective information on its multipurpose commercial values.
The objective of the study was to investigate the anti arthritic activity of the hydroalcoholic extract of the leaf of Psidium guyava linn against complete Freund's adjuvant induced arthritis in laboratory rats. Arthritis was induced in male wistar rats by administration of complete Freund's adjuvant in the sub plantar region of the hind paw. Diclofenac sodium (4 mg/kg/day p.o was used as the standard drug.The hydroalcoholic extract of Psidium guyava(HEPG) was administered at the following doses 50, 100, 200mg/kg/day p.o. The following parameters were measured: change in paw volume, body weight, diameter of the tibiotarsal joint and total leukocyte count in the blood. The results demonstrate that hydroalcoholic extract of Psidium guyava linn. at a dose of 200 mg/kg/day p.o showed significant anti arthritic activity.
The aim of this review is to provide a summary on multidisciplinary scientific information obtained from medicinal plants used worldwide to treat anxiety, focusing on pharmacological and clinical studies. The bibliographical investigation was carried out by consulting five peer-reviewed worldwide database publications for references, and patents. The information gathered on plants with attributed anxiolytic properties are presented as follows: (1) plant extracts with anxiolytic properties evaluated in animal models; (2) plants with clinical trials; (3) identified active compounds in plants that have been assayed in animal models; (4) mechanism of action of anxiolytic plant extracts and compounds; and (5) registered patents for anxiolytic plant preparations. We recorded 112 plant species belonging to 63 botanical families for which the anxiolytic properties had been tested in animal models. Eleven plant species to treat general anxiety disorders as well as eleven species to treat anxiety-associated conditions, had been documented by clinical trials. Thirty-three registers for active compounds belonging to five general types of secondary metabolites had also been recorded. The mechanism of action at the central nervous system level had been determined in 33 plant species, either in their extracts or isolated compounds. Forty-seven patent registrations for plant preparations to be used for the treatment of anxiety were included.
10. 1. 1. 1 The Purpose of Patch Testing Patch testing is a well-established method of diagnosing allergic contact dermatitis, a delayed type of hypersensitivity (type IV reaction). Patients with a history and clinical picture of contact dermatitis are reexposed to the suspected allergens under controlled conditions to verify the diagnosis. Besides testing patients with hand, arm, face or leg eczema (stasis dermatitis), testing of other types of eczema (atopic, seborrhoeic dermatitis, nummular eczema) is sometimes indicated, especially when the dermatologist suspects contact allergy to prescribed topical medicaments and their vehicles. Apart from its use to confirm a suspected allergic contact dermatitis, the patch test procedure can also be used before recommending alternative corti costeroids, skin care products, cosmetics, gloves, etc. in a particular patient. If the patient does not react to the alternatives tested, it is very unlikely that she or he will react to the products in ordinary use. 10. 1. 1.2 Standardization The first patch tests according to present principles were carried out in 1895 [1], but were preceded by some preliminary experiments [2] (see Chap. 1).
Repetitive washing with 0.01 mol/l sodium lauryl sulphate solution for one week was followed by a measurable skin function disorder as evaluated by corneometry, laser Doppler flowmetry, and transepidermal water loss (TEWL) measurements. The application of commercially available barrier creams (Marly Skin®, Saniwip®, Tactosan®) as well as the application of well-defined oil-in-water emulsions containing 10% urea or 10% glycerol, respectively, significantly reduced skin function deterioration following repetitive washings. Urea and glycerol containing oil-in-water emulsions were at least as effective as the most effective commercial barrier cream Tactosan and had the additional advantage of better user acceptance.
We have patch-tested 18 patients with skin symptoms who were exposed to cycloaliphatic epoxy resins (CA-ERs) in a factory where CA-ERs have been used to manufacture outdoor electrical insulators. The CA-ERs were Araldit CY 184 and Leku-therm X 100. Based on mass spectrometry and nuclear magnetic resonance (NMR) investigations, the CA-ERs were found to contain diglycidyl ester of hexahydrophthalic acid. Most of the patients were also exposed to diglycidyl ether of bisphenol A (DGEBA)-based epoxy resin modified by diglycidyl aniline (Lekutherm X 287). Insulators made of DGEBA-based epoxy resin are used for indoor mountings. The amount of DGEBA molecular weight (MW) 340 was 43% in Lekutherm X 287, and its highest concentration was 0.5% in CA-ERs. The highest total amount of nine reactive diluents [n-butyl glycidyl ether (GE), allyl GE, phenyl GE, cresyl GE, butanediol diglycidyl ether (DGE), hexanediol DGE, neopentyl glycol DGE, glycidyl ester of synthetic fatty acids (Cardura E 10), and glycidyl ether of aliphatic alcohols (Epoxide 8)] in the three epoxy resins was 0.4%. Diglycidyl ester of hexahydrophthalic acid was the main component of Araldit CY 184 and Lekutherm X 100, and the amounts were 50% (w/w) and 70% (w/w), respectively.
Patch tests were performed with the following epoxy compounds: DGEBA epoxy resin of standard series [1% petrolatum (pet.)]; the reactive diluents except butanediol DGE (0.25% pet.); and Araldit CY 184, Lekutherm X 100, and Lekutherm X 287 (each 1%, 0.3%, and 0.1% pet.). Of 18 patients, 12 showed allergic patch test reactions to CA-ERs (12 to Araldit CY 184 and 11 to Lekutherm X 100) and 7 patients to Lekutherm X 287, but only 1 patient to DGEBA epoxy resin. Of the 12 patients, 5 had patch test reactions to 1–4 of the diluents tested, possibly indicating cross-reactivity between CA-ERs and reactive diluents. Six patients had no allergic reactions to the epoxy compounds. None of the patients were allergic to the anhydride hardeners of the resins. The tests showed considerable irritation in 3 of 32 control patients with Araldit CY 184 and Lekutherm X 100 at the concentration of 1% pet., but lower concentrations provoked no reactions in the patients.
The present study indicates that CA-ERs are strong sensitizers in humans, and that CA-ER allergy is not revealed by testing with DGEBA epoxy resin. The most suitable test concentration for CA-ERs may be 0.5% pet. In most cases, minimization of exposure and certain industrial hygienic improvements will make it possible to continue work despite sensitization. The highest risk of exposure to CA-ERs occurs in the electrical industry, e.g., the manufacture of insulators.
A 32-year-old female dentist developed severe fingertip dermatitis. typical of acrylics allergy, and associated paronychia. On patch testing she was positive to eight acrylics, including ethyl acrylate, methyl methacrylate, 2-hydroxyethyl methacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, which were also shown by gas chromatography/mass spectrometry to be present in the particular dental products that she herself used at work. Five of these dental products, namely Scotchbond multipurpose primer and adhesive. Fuji LC liquid, and Dyract-PSA Prime adhesive and plastic, also gave allergic patch test reactions. The dentist had immediate relapses when returning to work and should change to a job in which she would not be exposed to acrylics. Dental acrylics need to be made safer, or used more carefully, because of the significant economic and mental stress inflicted on affected patients in cases of sensitization.
Three cases of allergic contact dermatitis from anaerobic acrylic sealants (all from Loctite products) and seven cases of allergic acrylate contact dermatitis from dental composite resins have been detected. The different types of acrylate patch test reactions are described.
Dendropanax tifidus Makino (family Araliaceae, syn. Gilibertia trificda Makino) has been reported as causing allergic contact dermatitis in Japan. To identify the major allergen, fractionated extracts of fresh leaves of Dendropanax tifidus were patch tested on 2 patients with hypersensitivity to the plant. Cis-9,17-octadecadiene-12,14-diyne-1,16-diol (I), an analog of falcarinol, was identified as an active component. 18 normal control subjects were patch tested with the leaf of Dendropanax tifidus and I diluted to 0.05% in pet. 4 of them showed active sensitization to the leaf of Dendropanax trifidus and I. Our results suggest that I is the major allergen of Dendropanax trifidus and is a strong sensitizer, The results of patch testing on patients and control subjects with the leaves of Fatsia japonica Decne. et Planch. and Hedera helix L., which also belong to the Araliaceae family, and urushiol are also shown. (C) Munksgaard, 1997.
: In most cases, allergic contact dermatitis (ACD), acquired through exposure to epoxy resin compounds (ERCs), is caused by the epoxy resin based on the diglycidyl ether of bisphenol A (DGEBA-ER). In rare cases an isolated allergy to non-DGEBA-ERs, reactive diluents, or hardeners occurs without positive patch tests to any other ERCs tested. During 1974 to 1990 we have had 113 patients with occupational ACD from ERCs. Thirty of the 113 patients (27%) had occupational ACD from epoxy hardeners. Five of these cases are presented here. Three cases of isolated hardener allergy were detected. One patient had contact allergy to diethylenetriamine from the hardener of a spray paint, and another from that of a mortar adhesive. Two patients, a painter and a process worker, had become allergic to 2,4,6-tris-(dimethylaminomethyl)phenol (tris-DMP) and to the isophoronediamine (IPDA) in the hardeners of epoxy paints and coatings that they handled. The painter had isolated allergies to the hardener compounds, but the process worker was also allergic to the DGEBA-ERs. The fifth patient had become sensitized to three components of the hardeners of concrete floor coatings, ie, to IPDA, trimethylhexamethylenediamine, and to a component containing 30% xylylenediamine. He was also allergic to the DGEBAERs. To find out about epoxy hardener allergies, patients should be tested with their "own" hardeners. The test concentrations are dependent on the free polyamine contents in the hardeners. Testing with isolated hardener compounds is highly desirable to identify the specific allergens.
Background: Patch testing is commonly used in dermatologic practice for the diagnosis of contact dermatitis. Objective: The objective of this study was to describe the patient population of an occupational contact dermatitis clinic and compare the results of patch testing in this setting with the pooled results from other patch test clinics. Methods: Patch testing was performed using standardized methodology in 14 clinics in North America. Results: The prevalence of positive patch test responses is influenced by the age and sex distribution of the population. When the Toronto occupational contact dermatitis clinic results were compared with those of the other centers in North America, there was an increased prevalence of positive responses to colophony, paraphenylenediamine, and nickel in the Toronto group. Conclusions: Although the patient mix is different in an occupationally oriented patch test clinic, when appropriate corrections are made for age and sex differences, the results of patch testing are generally similar to pooled results from a number of dermatology clinics. The differences in results do not reflect a strong occupational difference but may reflect a difference in exposure to various materials.
: Contact allergy to clothing is considered to be rare. Is the problem underrecognized? In a contact dermatitis referral practice, 13 of 462 patients (all dermatologist referred) were found to have a contact allergy to a formaldehyde textile resin finish or textile dye that was thought to be relevant to the patient's dermatitis. Pursuit of a diagnosis of clothing dermatitis can be frustrating due to the difficulty in obtaining patch test materials, interpreting findings, and ability to make practical recommendations to the allergic patient. This article reviews some of the more common questions that might arise as a dermatologist considers the problem of clothing dermatitis.
(C)1992American Contact Dermatitis Society, All Right Reserved
Chemicals used on fabrics to improve 10 different performance characteristics have resulted in irritant or allergic contact dermatitis. The most significant problem is due to formaldehyde and N-methylol compounds to produce durable press fabrics. Little is known about incidence of finish dermatitis or mode and amount of transfer of chemicals from fabric to skin.
There is no evidence that nickel-sensitive patients, when given a modern plastic-to-steel hip replacement, develop cutaneous reactions or loosening of their prostheses. However, eczema I occasionally seen with static metal prostheses and eruptions sometimes accompanied the use of the older types of joint prosthesis. Modern plastic-to metal joint replacements rarely cause sensitization to the composite metals. In the rare instances when this has been detetcted by patch testing, the affected patients have not developed eczema or loosening of their prostheses.
In addition lo previously presented patients with allergic contact dermatitis from cycloalipoatic epoxy resins (ERs), during 1974–1990, we have seen 4 patients with allergic contact dermatitis (ACD) caused by products containing uncured non-diglycidyl-ether-of-bisphenol-A ER. The patients were negative on patch testing with the standard ER based OT diglycidyl ether of bisphenol A (DGEBA-ER). The following non-DGKBA-ERs wore included in the causative agents: heterocyclic dimethylhydantoin ER. phenol novolak ER, and brominated ER. We were unable to Specify the type of ER in un epoxy primer used by the 4th patient. Apart from the ACD caused by the brominated HR. I of the patients also had IgE-mediated occupational rhinitis caused by methyl hexahydrophthalic anhydride (MHHPA), an epoxy hardener. The diagnosis was verified by positive prick tests and specific IgE determinations with MHHPA. Intense rhinitis evoked by a bronchial challenge with MHHPA confirmed the diagnosis. We stress the importance of performing patch testing with the relevant epoxy resins to which the patient has been exposed, in addition to patch testing with the standard ER.
The improvement of stratum corneum hydration is one of the most important claims in the cosmetic industry.
Objective assessment of moisturization can be done with devices based on electrical methods provided these instruments are used in an appropriate manner.
This paper deals with the biophysical basis behind these techniques and describes the most important variables, pitfalls and drawbacks related to measurements and current instrumentation. Individual-related and environment-related variables are also analyzed as well as study designs for predictive or use tests.
Practical suggestions for standardization of measurements are given.
Sweat and household detergents were shown to have the capacity to release nickel from stainless steel. This finding substantiates the thesis that the American-style stainless steel kitchen and other stainless steel commodities can be sources of skin contact allergy with nickel. Furthermore, a negative spot test (DMG) does not reflect the "safety" of a nickel alloy.
The first prescriptions for castor oil may well have been enscrolled on papyrus; certainly, the oil's cathartic properties have been recognized and employed therapeutically for centuries. Like some of its modern counterparts, castor oil has been prescribed at times without adequate pharmacological definition; indeed, its mechanisms of action are defined vaguely in classical pharmacological references, and only then in terms of an "irritant" or "stimulant" effect on the gut (1, 2). The past 15 years have seen a new interest develop in the drug and its actions on the gastrointestinal tract. A major incentive has been the insight given by this ancient remedy to the relationship between malabsorption of dietary fat and diarrhea. In 1890, Meyer (3) identified the active component of the oil as ricinoleic acid and this reference still constitutes a foundation for discussion of the drug's actions. Ricinoleic acid is a C~8, monounsaturated (at C9-1o), monohydroxylated
The maximization test for detecting contact allergens has proved to possess both sensitivity and specificity. However, modifications have become necessary because of excessive irritancy reactions to sodium lauryl sulfate. Fewer exposures are now recommended during induction and lower concentrations for challenge patch testing. Pre-testing of each subject in the panel is now standard procedure. The problem of interpreting challenge patch tests is discussed in detail.
A young woman developed erythema multiforme in association with multiple patch test reactions. Sequential patch testing revealed 2 true positive reactions (colophony and fragrance mix), and was not associated with flare of erythema-multiforme-type lesions. The development of erythema multiforme should be included in the list of possible adverse reactions to patch testing, albeit a rare occurrence.
Formaldehyde resins have been used to impart wrinkle resistance to clothing fabrics since 1926. After several patients with positive patch tests to formaldehyde resins had been examined, a study was undertaken of the records of all patch tests performed at the University of Louisville Patch Test Clinic and the Allergy Section of the Skin and Cancer Clinic of New York University Medical Center from January 1988 through April 1990 to determine the prevalence of positive patch-test reactions to formaldehyde-based textile resins and the clinical and demographic patterns associated with textile resin allergy.
Seventeen patients were identified at the two centers. Twelve were allergic to formaldehyde as well as to formaldehyde textile resins. Several clinical patterns were found, including accentuation of dermatitis in areas of tight clothing, primary occurrence in clothing-covered areas, and a chronic recalcitrant course. Ethylene urea melamine formaldehyde resin was the best screening agent with 14 definite positive reactions and one equivocal reaction.
Formaldehyde textile resin allergy is more common than has been previously recognized. Patch testing with one or more formaldehyde textile resins is indicated in patients with a particular pattern of dermatitis.
There are at least 2 quantitative variables when applying allergens to obtain sensitization: the absolute amount of allergen and the surface concentration. This review analyzes the limited studies on surface concentration and determines surface area threshold levels for the allergens documented in the literature.
Of a total of 3731 patients investigated between 1974 and 1990, 1844 (49.4%) had an occupational skin disease. Of them 142 (7.7%) had an occupational skin disease caused by epoxy compounds--135 patients (95%) had allergic contact dermatitis, five had irritant contact dermatitis, and two had contact urticaria. Apart from dermatoses, two patients had IgE-mediated asthma from exposure to DGEBA epoxy resins. Thus epoxy compounds are one of the main causes of occupational allergic contact dermatoses and can be considered potential causes of occupational asthma. The most frequent causes were epoxy resin compounds, which together induced 93% (132 cases) of all epoxy compound dermatoses. The three most common causative products were epoxy paints and their raw materials (31%, 41 cases), epoxy resin compounds used in electrical insulation (29%, 38 cases) and epoxy glues (18%, 24 cases). Fewer cases were caused by products containing epoxy acrylate and EPTMAC. The present study found that, in addition to contact allergy to DGEBA epoxy resins, contact allergy to epoxy hardeners, non-DGEBA resins and reactive diluents is common. Polyamine hardeners, most frequently MDA, DETA and TETA, rarely IPDA, tris-DMP, EDA, TMD and XDA, were the second commonest causes of contact allergy induced by epoxy resin compounds, after DGEBA epoxy resins. Cycloaliphatic epoxy resins and other non-DGEBA epoxy resins, including heterocyclic dimethyl hydantoin, phenol novolak and brominated epoxy resins, were the third commonest causes, and reactive diluents the fourth commonest cause of allergic dermatitis due to epoxy resin compounds. Most patients sensitized to reactive diluents were allergic to PGE, ortho-CGE, HDDGE and BDDGE, whereas fewer patients were sensitized to AGE, NPGDGE and BGE. Cross-sensitization between reactive diluents was common. Cardura E 10 and Epoxide 8 provoked no reactions. The present study also indicated that DGEBA epoxy resins with a high average MW ought to be regarded as potential sensitizers, and organic solvents probably promote sensitization to DGEBA, even if the amount of DGEBA is low in the causative products. When contact dermatitis induced by epoxy compounds is suspected, an accurate diagnosis is made with the use of detailed data on the patient's exposure and extensive patch testing, including tests with the patient's own products. No chemical can be used alone to screen for sensitization to all different contact allergens of epoxy compounds.(ABSTRACT TRUNCATED AT 400 WORDS)
All causes of occupational skin diseases seen during a 10-year period (1974-1983) at the Institute of Occupational Health in Helsinki were analyzed, and certain important groups of occupational dermatosis diagnosed at the Institute during 1974-1988 underwent further, detailed study. A total of 1,082 cases of occupational dermatoses were diagnosed between 1974 and 1983. Contact eczema was the most common diagnosis, comprising 1,052 cases (97%), of which 542 cases (52%) were allergic and 510 cases (48%) irritant eczema. The five most frequent causes of allergic eczema were metals (154 cases = 28%), plastic materials (150 cases = 28%), rubber and rubber chemicals (108 cases = 20%), formaldehyde (31 cases = 6%), and colorants (16 cases = 3%). When the statistics compiled by the Institute in 1946-1972 were compared to the data of the present study, allergy to plastic materials and rubber had increased considerably, accounting for 8% and 11% of cases in the first statistics, and for 28% and 20% of cases, respectively, in the latter. Chromium, which had previously ranked first of all allergens, fell to third place. Turpentine is no longer one of the main allergens, whereas formaldehyde still remains one of the most common causes of occupational allergic eczema. Rubber gloves caused two-thirds of all cases of rubber eczema diagnosed during 1974-1983. Rubber gloves represented 93%, whereas plastic gloves represented only 7% of all allergic glove dermatoses during that 10-year period. Acrylates, which are both skin irritants and sensitizers, were the fourth most common cause of eczema due to plastics during the same 10-year period. Textile, leather and fur dyes were the main causes of occupational eczema due to colorants during the 10-year period of 1974-1983. The present study also found that formaldehyde is a common cause of occupational allergic eczema, and a rare cause of occupational urticaria. The most common sources of formaldehyde allergy were glues, washing agents, textiles, formaldehyde solutions, and dust containing formaldehyde resins. All patients were allergic to 1% formaldehyde in water, and a positive dilution series confirmed the result. A provocation test commonly used when formaldehyde asthma is suspected is recommended to confirm the diagnosis of formaldehyde urticaria.
The eponym Kaposi's varicelliform eruption (KVE) describes a characteristic syndrome of disseminated vesicopustules that occasionally complicates a number of dermatoses. Among these, the most common is atopic dermatitis, and the inciting agent is most often herpes simplex virus (HSV). Very few reports of ocular herpetic disease exist among the many cases of KVE reported in the literature, despite extensive cutaneous involvement with herpetic lesions. We describe 10 patients with KVE, none of whom have developed evidence of herpetic ocular disease despite widespread facial involvement in all patients. All random conjunctival swab cultures performed in 3 patients were positive for growth of viable HSV. Although ocular exposure to HSV may commonly occur in KVE, ocular pathology due to this virus does not appear to be a common sequela.
The observations described here reveal several important aspects of the human immune system and its responses. The immune system is like most major physiologic systems in that it has tidy and predictable dose-response relationships. This applies both to the induction phase and also the elicitation or expression phase. There is thus a graded, dose-related increase in the magnitude of sensitization that applies throughout the range both of clinically detectable reactivity but also down to subclinical levels of response. It becomes possible to speculate about the kinetics of clonal expansion and the stage of the process at which specific T cells leave the lymph node to enter the circulation--the onset of clinical sensitivity. Additional stimulation to the system causes "boosting"--additional clonal expansion, already well known in the field of humoral immunology. Immune responsiveness appears to be normally distributed in the population, with one "tail" of the distribution containing "high responders" who are particularly susceptible to sensitization by environmental antigens. The high responder status reflects a propensity for increased activation of antigen-specific T cells during the induction of the response. Interestingly, the slope of the challenge dose-response curve and hence the expression phase is the same as that for normal subjects. An important factor in the activation or induction of an immune response is the concentration of antigen per unit area. Our studies on the influence of area of application of antigen indicate that at very small areas, between 3 mm and 1 cm across, changing area and hence number of antigen-bearing Langerhans cells may alter sensitization. Above a threshold or plateau level, changing the area makes very little difference, whereas change in the concentration per unit area, i.e., the number of antigen molecules per Langerhans cells, is a powerful determinant of sensitizing potency. We have not explored the upper limit of this phenomenon, i.e., maybe the relationship does not hold above a certain area or dose. The final series of observations showed that the application of antigen to skin pretreated with UVB or PUVA is followed by an absence of immunologic response. This state differs from that seen in mice in that it reflects a "failure" of activation of the immune system rather than a state of down-regulation or tolerance. Having established these ground rules, it will be possible to move on to a whole series of additional questions relating basic aspects of immunology to the applied areas of contact dermatitis.
The histopathology of systemic allergic contact dermatitis is usually characterized by spongiosis. A number of other much less common to rare histological findings have also been reported, including erythema multiforme-like eruption, vasculitis, urticaria, and miscellaneous groups.
We have investigated the effect on sensitization of altering the area of application of 2,4,dinitrochlorobenzene (DNCB) at a constant dose per unit area. We showed that, when an area of less than 1 cm2 is used, this area is critical in determining the degree of sensitization. This contrasts with previous work that showed, for larger areas, an alteration in the area of application had little effect on sensitization, whereas keeping the area constant and increasing the concentration of DNCB increased the degree of sensitization. We suggest that not only is the amount of antigen important in determining response, but also the distribution of the antigen as presented to the afferent limb of the immune system.
In order to discourage her habit of nail biting and to repair her damaged nails, a 50-year-old woman sought cosmetic improvement in a beauty salon, where a manicurist suggested the use of sculptured nails. A permanent paresthesia resulted from this procedure without allergic reaction.
11 common herbal topical medicaments in Hong Kong were selected for patch testing to study whether they could cause skin reactions under occlusive conditions. These included White Flower Oil, Hung Far Oil, Kwan Loong Medicated Oil, Tiger Oil, Jaminton Oil, Bee Brand Oil, Tiger Balm, Au Kah Chuen Skin Lotions, Mopiko Ointment, OronineH Ointment and Mentholatum. The former 7 were traditional Chinese herbal medicaments, the last one was made in USA and the remaining 2 were Japanese products. 20 patients were patch tested with the 11 medicaments. Hung Far Oil caused mild to moderately severe irritation in 8 patients; White Flower Oil, Jaminton Oil and Tiger Balm caused mild irritation in 1 to 3 patients; and the rest showed no positive reactions at all. With the exception of Hung Far Oil, all the other medicaments should be safe when applied openly. For Hung Far Oil, additional warning as to its irritant properties and the proper method for its application should be provided for the protection of its users.
Two female patients with aquagenic urticaria were studied in order to better clarify the pathogenesis of urticarial reactions to water. One patient suffered also from atopy and from cholinergic and chronic urticaria, and two of her sisters had noted aquagenic urticaria since puberty. The second patient had had aquagenic urticaria for only 2 years. Local applications of ethyl alcohol (96%) to the patients' skin did not elicit any lesions, and pretreatment of the skin with topically applied atropine did not inhibit whealing in response to water. Intracutaneous injections of aqueous extracts of human callus resulted in reproducible burning sensations in the patients' skin but not in control skin. Injections of buffer alone or of supernatants of stimulated epidermal cell suspension induced no abnormal reactions in patients' skin or control skin. Callus extracts also caused in vitro basophil histamine release from patients' peripheral blood basophils but not from cells of a healthy volunteer. These data suggest that patients with aquagenic urticaria react to a water-soluble antigen in the epidermal horny layer that diffuses into the dermis to cause histamine release from sensitized dermal mast cells.
7 patients were occupationally sensitized to dental composite resin products (DCR): 6 dental nurses and 1 dentist. All had a positive patch test to their DCR. 2 independent types of allergy were seen; (a) aromatic epoxy acrylate, and/or (b) aliphatic acrylates. 4 out of 5 patients reacted to BIS-GMA, the most widely used aromatic epoxy acrylate in DCR, but not the dentist. She and 2 dental nurses were allergic to aliphatic acrylates, including triethylene glycol dimethacrylate (TREGDMA) and triethylene diglycol diacrylate (TREGDA). 4 patients were allergic to epoxy resin (ER) (containing mainly MW 340), possibly an impurity in some DCR. 2 patients were also allergic to methyl methacrylate (MMA): the dentist, had been exposed to MMA, but the nurse's exposure was uncertain. 1 patient was also allergic to rubber gloves, 2 to rubber chemicals but not their gloves, and 5 to disinfectants used. diagnosis was delayed as long as 13 years in spite of previous patch testing. Dermatologists need to use the patients' own DCR and the (meth)acrylate series for patch testing. No dental nurses could continue their occupation, but the dentist could occasionally handle DCR if wearing PVC gloves. Dental personnel need to know about the risks of DCR, and use no-touch techniques and protective gloves.
Patients with a contact allergy to chromium, cobalt and/or nickel, patch test verified before implantation of a metallic orthopaedic device, were followed up years later by clinical and radiographic examination as well as with epicutaneous and intracutaneous tests. Eighteen patients had been exposed to an orthopaedic implant for several years (mean 6.3 years) containing a metal to which they were allergic. None had suffered any dermatologic or orthopaedic complications attributable to the contact allergy.
The immune response to herpes simplex virus (HSV) was studied in 59 patients with primary and recrudescent facial HSV infections. The patients included nine with atopic eczema, seven of whom had eczema herpeticum (EH). All patients had antibodies to HSV (measured by ELISA) and all but three had HSV-specific cell mediated immunity (CMI) (measured by in vitro lymphoproliferation). Thirteen control subjects were negative for both tests. All three patients with absent CMI to HSV had suffered from severe EH and had depressed CMI to HSV for several months following an attack. In two of these EH patients, a positive CMI response was produced by in vitro removal of CD8 + ve T lymphocytes from peripheral blood mononuclear cells using a panning technique. Thus the absence of CMI to HSV in these patients was due to suppressor cell function rather than a lack of specifically responsive cells. The other four EH patients with normal CMI to HSV had suffered less severe EH, but no association between the absence of CMI to HSV and serum IgE level or activity of the eczema was apparent in the atopic patients. No specific anti-HSV IgE antibody was detectable.
High-performance polymerizable anaerobic sealants originated in 1953 and are used to lock metal parts together chemically. A case of hand contact dermatitis from Loctite RC/601, 242, and 504 is reported in a 60-year-old machine assembler. This diagnosis was documented by positive patch tests of the product and of three of the components: polyethylene glycol dimethacrylate, hydroxypropyl, and hydroxyethyl methacrylate. This is the third report of contact dermatitis caused by these sealants in the United States, is the second in the world on hydroxypropyl methacrylate, and is another example of the wide environmental use of potentially sensitizing acrylic resins.
The manufacture of soft, disposable contact lenses, which are left in place for 2 weeks and then discarded, is a new application of the UV-cured polyacrylates. Two laboratory technicians, exposed to the monomers used during manufacture, developed an occupational hand dermatitis. They were patch tested with the ICDRG standard series using Finn Chambers® on Scanpor®, and supplementary tests with their own materials. The reactions were read as recommended by the ICDRG. The factory kindly provided samples of the constituents of the lenses. They contained the following chemicals: 2-hydroxyethyl-acrylate (HEA), 2-hydroxyethyl-methacrylate (HEMA), ethyleneglycol-di-methacrylate (EDMA) and Darocur® 1173 (2-hydroxy-2-methyl-1-phenylpropane-1-on) as a photocatalyst. The purity of HEA and HEMA were 98% and of EGDMA 95% as determined by HPLC analyses. Patch tests with HEA 0.1% pet. on 17 healthy controls were negative.