Patch testing and sensitization to multiple drugs.

BACKGROUND: Adverse drug reactions pose an increasing diagnostic challenge in hospitals and in outpatient clinics. When consecutive or repeated allergic drug eruptions are suspected, patch testing is a useful diagnostic tool for determining the causative drugs. OBJECTIVES: The aim of the study was to identify patient cases with multiple delayed-type drug sensitizations by using patch testing. METHODS: Eight hundred and eleven patients with suspected drug allergy were patch tested during a 9-year period. RESULTS: Multiple delayed drug sensitizations were found in 12% of those patients with positive results in drug patch testing. CONCLUSIONS: Drug patch testing is useful in cutaneous adverse drug reactions where multiple drugs are suspected. Multiple drug sensitizations can be found in a proportion of patients who have delayed drug allergies. In addition to drug reactions with eosinophilia and systemic symptoms, these patients may have repeated exanthemas or contact dermatitis.

[Update on current care guidelines: Allergen specific immunotherapy]. / Siedätyshoito.

Immunotherapy involves the specific treatment of IgE-mediated allergic diseases, indicated for allergic rhinitis and conjunctivitis, allergic asthma, insect sting (bee and wasp) allergy, and food allergy (especially cow's milk, egg and wheat). Subcutaneous injection immunotherapy with pollens (both trees and grass), animal danders, insect venoms and house dust mite preparations for allergic rhinitis and asthma is effective for both adults and children. Sublingual immunotherapy indicated for allergic rhinitis caused by grass pollens (especially timothy), is effective and appears to be a safe route of administration. Specific oral tolerance induction is used in children over five years of age with severe food allergy.

Non-occupational contact sensitization to epoxy resin of bisphenol A among general dermatology patients.

BACKGROUND: Sensitization to epoxy resins often results from occupational exposure in various fields of construction and industry. Non-occupational sensitization sources and environments have remained overlooked. OBJECTIVES: To analyse non-occupational and occupational contact sensitization to epoxy resin of bisphenol A among general dermatology patients. Special attention was paid to patients sensitized from non-occupational sources. PATIENTS AND METHODS: During a 10-year period, 6042 general dermatology patients were patch tested with epoxy resin (bisphenol A) in the Dermatology Clinic of Turku University Hospital. The clinical data and the sources of occupational and non-occupational exposure to epoxy resin were analysed in sensitized patients. RESULTS: Epoxy resin sensitization was found in 59 patients. Non-occupational sensitization was found in 21 (35%) patients, whereas the number of occupational cases was 38 (65%). The most common sources of non-occupational epoxy resin sensitization were materials used in domestic renovation and construction projects and in boat repair. CONCLUSIONS: Non-occupational sensitization sources account for approximately one-third of epoxy resin sensitization cases, and therefore represent an important risk among hobbies and leisure activities.

Gum arabic as a cause of occupational allergy.

Background. Gum arabic is a potential sensitizer in food industry. Methods. We examined 11 candy factory workers referred to examinations due to respiratory and skin symptoms paying attention to exposure and sensitization to gum arabic. Skin tests, pulmonary function tests, and respiratory provocation tests were carried out as indicated by the symptoms and findings. Results. Occupational asthma, caused by gum arabic was diagnosed in 4/11 candy factory workers and two of them had also occupational contact urticaria and one had occupational rhinitis. One of them had oral symptoms associated with ingestion of products containing gum arabic. Conclusions. Airborne exposure to gum arabic may cause sensitization leading to allergic rhinitis, asthma, and urticaria.

[Drug-induced skin reactions]. / Lääkeaineiden aiheuttamat ihoreaktiot.

Antimicrobials and anti-inflammatories are the most common drugs causing skin reactions, but reactions are also brought about by ACE inhibitors, antiepileptics, many anticancer and certain other drugs. Exanthema and urticaria are the most common types of drug reactions. Urticaria may or may not be accompanied by angioedema or anaphylaxia. Possible life-threatening drug reactions include also toxic epidermal necrolysis, Stevens-Johnson syndrome and eosinophilia with systemic symptoms. A drug reaction resembles a typical allergic reaction. Diagnosis is based on the clinical picture and anamnesis.

Nickel sensitization in orthodontically treated and non-treated female adolescents.

BACKGROUND: The importance of the nickel exposure from fixed orthodontic appliances is under continuous discussion. OBJECTIVES: Our aim was to investigate nickel allergy and the risk of nickel sensitization among female adolescents during orthodontic treatment with fixed appliances as compared with non-treated female adolescents. SUBJECTS AND METHODS: Female patients starting or with ongoing orthodontic treatment (n = 30) and young females without a history of orthodontic treatment (n = 140) were studied. Patch testing with 5% nickel sulfate was carried out twice on each participant with an approximately 1-year interval. The subjects completed a questionnaire before the first testing. RESULTS: None of the 7 orthodontic patients with a positive patch test reaction to nickel had any clinically visible intraoral allergic symptoms during their treatment. No significant difference was seen in the occurrence of positive nickel reactions in regard to orthodontic treatment, or between the first and second tests. In the treatment group, 2 patients changed from nickel-positive to nickel-negative during the observation period, and one patient showed an opposite change. The quantity and course of changes in the repeated nickel patch test reactions did not differ significantly between the subjects with and without orthodontic treatment experience. CONCLUSIONS: Nickel sensitization from orthodontic appliances is improbable, but nickel sensitization may develop also during orthodontic treatment.

The relevance of chlorhexidine contact allergy.

BACKGROUND: Chlorhexidine is used for disinfection of skin and mucosae in medicine and dentistry. Prolonged exposure may lead to contact sensitization and allergic contact dermatitis or stomatitis. OBJECTIVES: The purpose of this study was to analyse the sources of chlorhexidine exposure and sensitization, and to obtain data on the prevalence of sensitization and chlorhexidine-related contact allergy. PATIENTS AND METHODS: From 1999, patch testing was performed with chlorhexidine digluconate (0.5% aq.) on 7610 general dermatology patients with suspected contact allergy at the Turku University Hospital Dermatology Department. The medical records were reviewed concerning the patients' exposure to chlorhexidine. RESULTS: A positive patch reaction to chlorhexidine was seen in 36 patients (0.47%). Current dermatitis or stomatitis caused by chlorhexidine-containing topical medicaments was seen in 5 patients. Chlorhexidine sensitization contributed to the current dermatitis in 11 patients. A history of earlier exposure to chlorhexidine-containing products was recalled by only 16 sensitized patients, whereas no exposure was revealed in 4 cases. CONCLUSIONS: Chlorhexidine-containing corticosteroid creams, skin disinfectants and oral hygiene products are principal sources of chlorhexidine contact sensitization. Exposure to chlorhexidine in cosmetics may lead to delayed improvement of eczema in sensitized patients, emphasizing the importance of identifying the potential cosmetic sources.

Contact sensitization to methylisothiazolinone in Finland--a multicentre study.

BACKGROUND: Antimicrobials constitute the second most common cause of contact allergy to cosmetics. Methylisothiazolinone (MI), previously always used together with methylchloroisothiazolinone (MCI), has recently been approved in the EU for use on its own in cosmetics and also various industrial products. MCI has been classified as an extreme-strong and MI as a strong-moderate sensitizer. OBJECTIVES: To study the frequency of positive patch test reactions to MI, and its relevance and relation to MCI/MI sensitivity, in Finland. METHODS: Over a period of 3 years (2006-2008), MI 0.1% (1000 ppm) and 0.03% (300 ppm) were patch tested in 10,821 patients at eight Finnish dermatological clinics. During 2008, patients with positive reactions to MI were asked to take part in a repeated open application test (ROAT). RESULTS: Of the patients tested, 1.4% and 0.6% showed positive patch test reactions to 0.1% and 0.03% MI, respectively. Sixty-six per cent of those who were MI-positive were also positive to 100 ppm MCI/MI. Thirty-three agreed to undergo the use test, and 10 of these gave positive results (30%). CONCLUSIONS: Our data show that MI used alone also potentially induces contact allergy. Careful monitoring is needed to determine whether or not this antimicrobial is safe to use in cosmetics.

Sensitization to thiourea derivatives among Finnish patients with suspected contact dermatitis.

BACKGROUND: Thiourea derivatives in rubber products may induce contact sensitization and allergic contact dermatitis. Sensitization is most often from neoprene rubber, but the multitude of possible sensitizing products has remained poorly characterized. OBJECTIVE: The aim of this study was to collect information on the occurrence of thiourea-related contact allergy and to show novel sources of sensitization. PATIENTS AND METHODS: A mixture of dibutyl-, diethyl-, and diphenylthiourea was included in patch test baseline series in five Finnish dermatology clinics during 2002-2007. In addition, an extended series of rubber chemicals was tested in patients with suspected rubber allergy. Sources of sensitization to thioureas were analysed in sensitized patients. RESULTS: Thiourea mix yielded positive patch test reactions in 59 of 15,100 patients (0.39%); 33/59 patients were also tested with individual rubber chemicals. Diethylthiourea was positive in 24/33, diphenylthiourea in 5, and dibutylthiourea in 1 patient. The most common sources of sensitization included various neoprene-containing orthopaedic braces, sports equipment, and foot wear. CONCLUSIONS: The sources of sensitization to thiourea chemicals were detected in most cases. These sources comprise a heterogenous group of products extending from orthopaedic materials to sports equipment.

[Sweet lupin--a new food allergen]. / Makea lupiini--uusi ruoka-allergeeni.

Lupin, a legume with good nutritional value, is used in food production today, most often in bakery products. In Finland, lupin is a labelled ingredient in very few products. Clinically relevant lupin allergy, even anaphylaxis, often occurs in patients without atopic background or other food allergies, whereas lupin sensitization without clinical relevancy most commonly seems to represent cross reactivity to other legumes. Lupin allergy should be suspected and studied in patients with adverse reactions to food, and patients with allergy to other legumes should be advised about possible lupin allergy, as well.

Sensitization to dimethyl fumarate with multiple concurrent patch test reactions.

BACKGROUND: Chairs and sofas imported from China to Europe were shown to contain dimethyl fumarate (DMF), a sensitizing, volatile chemical. Many of the sensitized patients also had positive patch test reactions to acrylates. OBJECTIVES: To analyse the occurrence and strength of DMF sensitization and the appearance of concomitant reactions. METHODS: Patch testing with DMF in concentrations of 0.1-0.00001% was carried out in 37 patients. Diethyl fumarate (DEF), diethyl maleate (DEM), dimethyl maleate (DMM), ethyl acrylate (EA), methyl acrylate (MA), and methyl methacrylate (MMA) were also tested with a dilution series at equimolar concentrations. RESULTS: The lowest concentration of DMF eliciting a reaction varied between 0.0001% and 0.1% and all but four patients reacted concurrently to DEF. DEM elicited positive patch test reactions in 21/37 patients and DMM reactions were seen in all 9 patients tested. EA elicited positive reactions in 13/37 patients and a positive MA reaction was seen in 7/37 patients, 2 of whom also reacted to MMA. CONCLUSIONS: The strength of the sensitization to DMF showed variation and concurrent reactions were common. Concurrent reactions to (meth)acrylates were seen in patients, who reacted to lower (0.001% or less) DMF concentration probably elicited by cross-reactivity.

Lupin allergy and lupin sensitization among patients with suspected food allergy.

BACKGROUND: Lupin, a legume with good nutritional value, is used in food production today, most often in bakery products. Lupin sensitization is often seen among patients with reactions to legumes, but the number of reports describing lupin anaphylaxis is also increasing. OBJECTIVE: To investigate the occurrence of lupin sensitization, cross-reactivity, and lupin allergy among patients with suspected food allergy in Finland, where lupin is a labeled ingredient in few products. METHODS: The occurrence of positive skin prick test (SPT) reactions to lupin seed flour was studied among 1522 patients with suspected food allergy from November 1, 2005, through December 31, 2007. Clinical histories and diagnostic SPT results were analyzed among patients with positive SPT results to lupin. For 1 patient, ImmunoSpot and lupin radioallergosorbent test inhibition methods were used. RESULTS: Lupin sensitization was shown in 25 of 1522 patients (1.6%), and probable lupin allergy was diagnosed in 7 of 25 patients, in whom the clinical symptoms varied from anaphylaxis and respiratory symptoms to contact urticaria and itchy mouth. Cross-reactions or concurrent reactions to other legumes were seen in 18 of 25 patients. CONCLUSIONS: Clinically relevant lupin allergy often occurs in patients without atopic background or other food allergies, although lupin sensitization most commonly seems to represent cross-reactivity to other legumes. The occurrence of lupin allergy in a country where lupin has not been traditionally used is surprisingly common, suggesting that short-term use of modest amounts of lupin can cause serious allergic reactions.

Allergy to carmine red (E120) is not dependent on concurrent mite allergy.

BACKGROUND: Positive skin prick test (SPT) reactions to carmine red (E120) have been reported to occur concurrently with reactions to mites. The relationships between positive SPT reactions to carmine, carmine allergy and concurrent mite reactions are unknown. The aim of this study was to analyse the prevalence of carmine sensitization and its clinical importance among patients with suspected allergy to food additives. METHODS: The occurrence of positive SPT reactions to mites was studied in 6,464 patients: 3,164 were tested with carmine and 2,837 with shrimp. Carmine ingestion-associated symptoms were registered at the time of testing. Patients with positive SPT to carmine received a follow-up questionnaire on their symptoms 1-5 years later. RESULTS: Positive SPT reactions to carmine were seen in 94 patients (3.0%) of whom 74% also had positive SPT reactions to mites and 22% to shrimp. Carmine ingestion-associated symptoms were not dependent on concurrent mite reactivity in 39/94 (42%) patients. CONCLUSIONS: Carmine sensitization without sensitization to mites is seen in one fourth of the patients. Allergic reactions to carmine are not dependent on concurrent reactivity to mites.

Sources of sensitization, cross-reactions, and occupational sensitization to topical anaesthetics among general dermatology patients.

BACKGROUND: Contact sensitization to local anaesthetics is often from topical medicaments. Occupational sensitization to topical anaesthetics may occur in certain occupations. OBJECTIVES: The aim of the study was to analyse the occurrence of contact sensitization to topical anaesthetics in general dermatology patients. PATIENTS AND METHODS: Patch testing with topical anaesthetics was carried out in 620 patients. Possible sources of sensitization and the clinical histories of the patients are analysed. RESULTS: Positive patch test reactions to one or more topical anaesthetics were seen in 25/620 patients. Dibucaine reactions were most common (20/25), and lidocaine sensitization was seen in two patients. Six patients had reactions to ester-type and/or amide-type anaesthetics concurrently. Local preparations for perianal conditions were the most common sensitizers. One patient had developed occupational sensitization to procaine with multiple cross-reactions and with concurrent penicillin sensitization from procaine penicillin. CONCLUSIONS: Dibucaine-containing perianal medicaments are the major source of contact sensitization to topical anaesthetics. Although sensitization to multiple anaesthetics can be seen, cross-reactions are possible. Contact sensitization to lidocaine is not common, and possible cross-reactions should be determined when reactions to lidocaine are seen. Occupational procaine sensitization from veterinary medicaments is a risk among animal workers.

Positive patch test reactions to gentamicin show sensitization to aminoglycosides from topical therapies, bone cements, and from systemic medication.

BACKGROUND: A history of prolonged use of topical antimicrobials is common among patients with positive patch test reactions to gentamicin and to aminoglycosides. OBJECTIVES: The aim of this study was to show sources of gentamicin sensitization in patients with positive patch test reactions to gentamicin. PATIENTS AND METHODS: About 7814 patients were patch tested with a baseline patch test series and 620 of them were further tested with gentamicin. The clinical histories, concurrent contact sensitivities, and sources of sensitization are analysed among these patients. RESULTS: Positive patch test reactions to gentamicin were seen in 29/620 patients, most of whom (18/29) also reacted to neomycin and to kanamycin (7/29). Mean age of the gentamicin-positive patients was 62 years, but three young operating room nurses with hand dermatitis had a history of gentamicin exposure from bone cement. Among the 11/29 neomycin-negative patients, a history of exposure to different aminoglycosides was apparent, and one patient had a history of systemic netilmicin-medication-associated exanthema. CONCLUSIONS: Positive patch test reactions to gentamicin reflect sensitization to different aminoglycosides for which gentamicin seems to represent a sensitive indicator. Gentamicin sensitization may result from occupational exposure to gentamicin containing bone cements or from systemic medication with aminoglycosides.

Contact sensitization to 4,4'-diaminodiphenylmethane and to isocyanates among general dermatology patients.

BACKGROUND: Diisocyanates and 4,4'-diaminodiphenylmethane (MDA) are industrial sensitizers. Occupational asthma is a risk among workers exposed to diisocyanates. Exposure may also lead to contact sensitization and allergic contact dermatitis. OBJECTIVE: The aim of this study was to determine the occurrence of contact sensitization to MDA and to diisocyanates among general dermatology patients. PATIENTS AND METHODS: Patch testing with MDA was carried out in 1595 patients. Diphenylmethane-4,4'-diisocyanate (MDI) and toluene-2,4-diisocyanate (TDI) were tested in 1023 patients and isophorone diisocyanate (IPDI) and 1,6-hexamethylene diisocyanate (HDI) in 433 patients. The clinical data and sources of exposure are analysed. RESULTS: MDA reactions were seen in 17 (1.1%) patients and MDI reactions in 4 patients. Six MDA-positive patients reacted to p-phenylenediamine and two to epoxy chemicals. 5/10 of the TDI reactions were seen concurrently with reactions to MDI, MDA, HDI, or to IPDI. IPDI reactions were seen in eight patients and HDI reactions in two patients. Possible sources of exposure were traced in most patients, although the association with the current dermatitis was not apparent in all cases. CONCLUSION: (Di)isocyanates may induce contact sensitization with or without allergic contact dermatitis.