Use Of Patch Testing Research Articles

Cross-reactions among hair dye allergens

Background: p-Phenylenediamine (PPD) is an important hair dye allergen, but there remains a reasonable suspicion that other hair dye chemicals may also be responsible for a proportion of the clinical burden of hair dye allergy. Objective: To assess to what extent presently assessed additional patch test agents contribute to the diagnosis of non-PPD hair dye allergy. Methods: A retrospective analysis was conducted of patch test results with hair dye allergens, focusing on the extent to which patients who were positive for allergic reactions to other hair dye allergens also had a concomitant positive reaction to PPD. Results: For the hair dye allergens other than p-toluenediamine (PTD), reactions in the absence of a concomitant positive reaction to PPD were very rare. Positive reactors to PTD were also positive for reactions to PPD in 5 of every 6 cases. Pyrogallol positives often occurred in the absence of a PPD positive, but were never judged to be of clinical relevance. Conclusions: Hair dye chemicals other than PPD may be of importance, but the presently tested materials, with the possible exception of PTD, are normally positive only when a PPD-positive reaction is also present, suggesting that their use in patch testing in hair dye allergy is likely to be of limited value.

Patch Testing for the Diagnosis of Anticonvulsant Hypersensitivity Syndrome

Anticonvulsant hypersensitivity syndrome (AHS), also known by the other names drug rash (reaction) with eosinophilia and systemic symptoms (DRESS) and drug-induced hypersensitivity syndrome (DIHS), is a rare and potentially fatal reaction that occurs in susceptible patients after exposure to certain drugs, including aromatic anticonvulsants. Because of its ill-defined clinical picture and resemblance to other diseases, the diagnosis of AHS is often difficult and requires a safe and reliable diagnostic test. The skin patch test has been proven to be very useful for prediction and diagnosis of some types of hypersensitivity reactions such as delayed drug eruptions to beta-lactam antibacterials. However, the diagnostic value of patch testing for AHS is yet to be determined and its negative predictive values (NPVs) and positive predictive values (PPVs) are still unknown. This systematic review attempts to evaluate the usefulness of patch tests in the diagnosis of AHS and to examine different technical aspects of patch testing that may contribute to its performance. We included studies in which aromatic anticonvulsant drugs are the likely causes of the hypersensitivity reaction. Analysis of original publications from 1950 to August 2008 and cited in PubMed, MEDLINE and EMBASE has revealed contradictory findings, possibly due mainly to the use of unstandardized methods. Numerous factors have been suggested to affect the final result of the test, including the following: type of drug tested; concentration of drug and vehicle used; timing of the test after exposure; and the clinical picture of the reaction. The PPV of the test in optimal conditions was as high as 80-90% depending on the drug tested. On the other hand, this value is around 10-20% in many other published studies. Although patch testing may be a useful diagnostic test for AHS, accurate determination of its sensitivity and specificity is yet to be achievable due to the lack of a gold standard test against which the performance of patch testing can be measured. Its PPV appears to be higher than its NPV, a matter that necessitates the use of other confirmatory tests in case of negative patch tests (e.g. careful systemic rechallenge). The benefit of testing appears to be maximal with certain drugs (i.e. carbamazepine and phenytoin) and for specific clinical manifestations (strong reactions). It should be performed 2-6 months after recovery from the date of the ADR for best results, with adequate vehicle control.

The Use of Patch Tests in Determining Hypersensitivity to Etanercept and Infliximab—Reply

The Use of Patch Tests in Determining Hypersensitivity to Etanercept and Infliximab—Reply

The Use of Patch Tests in Determining Hypersensitivity to Etanercept and Infliximab

The Use of Patch Tests in Determining Hypersensitivity to Etanercept and Infliximab

Use of patch testing for identifying allergen causing chronic urticaria

Use of patch testing for identifying allergen causing chronic urticaria

Foot Dermatitis: A Shoe-In

Symmetric dermatitis on the dorsum of the feet suggests allergic contact dermatitis from footwear; it also should suggest the use of patch testing to determine the responsible allergen. Warshaw and co-workers sought to identify the frequency with which various allergens caused shoe dermatitis. They reviewed the records of 10,061 patients patch tested with the North American Contact Dermatitis Group (NACDG) standard screening panel at various sites between 2001 …

Use of patch testing for identifying allergen causing chronic urticaria

The aim of this present study was to evaluate the role of patch testing for the etiological diagnosis of chronic urticaria (CU) by using the Indian standard battery of patch test allergens approved by Contact and Occupational Dermatitis Forum of India (CODFI). A total of 57 cases with chronic urticaria were tested with the Indian standard battery of allergens. All those cases that showed allergy to patch test allergens were advised to avoid contact with the allergen(s) to whom they had allergy; they were also advised to avoid/restrict allergens in the diet. This avoidance/restriction was advised for a period of six weeks. During this period, clinical improvement of each patient was evaluated and recorded at weekly intervals. Out of the 57 cases of CU, 11 patients showed positive reactions to one or more patch test allergens. Nine out of eleven showed complete disappearance of CU by 2-3 weeks on avoidance of the allergen and this improvement continued till the end of six weeks. The remaining two cases showed partial recovery from CU during the same period. Patch testing is a safe, simple and inexpensive alternative that can be used for the etiological diagnosis of chronic urticaria before undertaking expensive investigations.

Use of patch test in fixed drug eruption due to metamizole (Nolotil®)

Use of patch test in fixed drug eruption due to metamizole (Nolotil^®)

The use of patch testing in the diagnosis of food allergy

Diagnosing food allergies can be challenging to the practitioner. Our armamentarium includes standardized skin prick testing, radioallergoimmunosorbent (RAST) testing, and food challenges. These methods have certainly been helpful in the IgE-mediated disorders, including urticaria and anaphylaxis. However, diagnosing patients who have the non-IgE (cell-mediated) or mixed (IgE and cell-mediated) disorders remains challenging with our current diagnostic methods. Recent studies have examined the use of patch testing for these food-allergic patients, specifically those with atopic dermatitis and eosinophilic esophagitis. In this article, we review literature regarding patch testing: its methods, its statistical usefulness, and its potential future role.

Cross-reactivity among p-amino group compounds in sulfonamide fixed drug eruption: diagnostic value of patch testing.

We studied 28 patients with fixed drug eruption (FDE) caused by sulfonamide antibiotics to investigate cross-reactivity between sulfonamide derivatives and p-amino compounds and to explore the usefulness of patch testing, as an alternative to controlled oral challenge testing (COCT), in diagnosis within this clinical area. COCT with sulfamethoxazole (SMX), sulfadiazine (SDZ), sulfamethizole (SMZ), furosemide (FU), procaine (PRO) and glipizide (GPZ) was performed. Patch testing (PT) with SMX and SDZ was carried out. In all patients, the diagnosis of FDE was confirmed by positive COCT and allergy to trimethoprim ruled out by COCT. 42.8 and 31.8% of the SMX-induced FDE patients reacted to SMZ and SDZ, respectively. All patients (n = 28) tolerated FU, PRO and GPZ. COCT performed with the 3 sulfonamide antibiotics in 12 patients was positive in 2 subjects with the 3 drugs, in 2 patients only with SMX and SMZ and in the remaining 8, SMX was the only causative drug. PT was positive in 5 of 25 patients positive on COCT. The probability of obtaining a positive PT was higher among patients who had a residual lesion than that among those who lacked this. Cross-reactivity between different sulfonamide antibiotics is thus variable, being most likely between SMX and SMZ. We have found no cross-reactivity between sulfonamide antibiotics and other sulfonamide derivatives or p-amino drugs in FDE. PT is a useful tool in the diagnosis of FDE, especially if there are residual lesions, because it avoided the need for COCT in 20% of patients.

Changing patterns of contact allergy in chronic inflammatory ear disease.

Chronic inflammatory ear disease comprises a wide range of conditions. Although contact allergy to topical medicaments is common in such conditions, the causes of these reactions have not been examined in a large series for over a decade. Our aim was to investigate the major sensitizers recorded in 179 patients over the last 17 years. Medicament contact allergic dermatitis was diagnosed in 45 patients (25%), of whom 34 (76%) demonstrated a relevant allergy to neomycin, 28 (62%) to framycetin, 11 (31%) to gentamicin, 8 (18%) to quinoline mix and 5 (11%) to caine mix. Of all neomycin-allergic patients, 28 (76%) were also allergic to framycetin and 12 (43%) to gentamicin. Comparing the first 60 patients (1985-94) to the most recent 60 (1998-2002) identified a significant recent reduction in the number of patients allergic to neomycin (P = 0.002) and framycetin (P = 0.050), with a non-significant reduction in the total number diagnosed as medicament-allergic (P = 0.066). We have therefore demonstrated a high frequency of medicament contact allergy in chronic inflammatory ear disease, supporting the routine use of patch testing in these patients. We have also shown a significant recent reduction in the number of such patients with allergy to neomycin and framycetin.

North American Contact Dermatitis Group Patch-Test Results, 2001-2002 Study Period

Allergic contact dermatitis is a significant cause of cutaneous disease affecting many individuals in the home and at the workplace. Patch testing is the most worthwhile diagnostic tool for the evaluation of patients with suspected allergic contact dermatitis. This study reports the results of patch testing from January 1, 2001, to December 31, 2002, by the North American Contact Dermatitis Group (NACDG). Patients were tested with an extended screening series of 65 allergens. A standardized patch-testing technique was used. Data from these patients were recorded on a standardized computer entry form and analyzed. Sixty-five allergens were tested on 4,913 patients. The top 10 allergens remain the same in this study period as in the 1999-2000 study period: nickel sulfate (16.7%), neomycin (11.6%), Myroxilon pereirae (balsam of Peru) (11.6%), fragrance mix (10.4%), thimerosal (10.2%), sodium gold thiosulfate (10.2%), quaternium-15 (9.3%), formaldehyde (8.4%), bacitracin (7.9%), and cobalt chloride (7.4%). Of the 4,913 patients tested, 69% had at least one positive allergic patch-test reaction. Of all patients, 15.8% had occupation-related dermatitis; 15.4% were determined to have irritant contact dermatitis, and 11.1% of the 15.4% had a relevant reaction to an occupational irritant. Of all patients tested, 16.7% had a relevant reaction to an allergen not in the NACDG standard series, and 5.5% had a relevant reaction to an occupational allergen not in the standard series. Our findings once again reinforce the need for a more comprehensive group of diagnostic allergens than those found in the standard screening kits. The usefulness of patch testing is enhanced when a greater number of allergens are tested, especially nonstandard allergens occupationally encountered.

Patch testing for allergic contact dermatitis in the allergist office.

The identification of allergens responsible for allergic contact dermatitis (ACD) is key to the management of this disease. The patch test (PT) is the only safe, objective, scientific, and practical method for the diagnosis of ACD. There is no single PT panel that will screen all the relevant allergens in a patient's environment. It is generally thought that 20 to 30 allergens in routine screening tests can identify 50% to 70% of clinically relevant ACD. However, the usefulness of patch testing is enhanced with the number of allergens tested. Although the PT might be simple to apply, it might be difficult to read, interpret, and correlate to the patient's symptoms. A familiarity with the patient's environment, the process of the industry in that environment, and the uses of various chemicals in the industry is needed in most cases.

Concurrent cereal allergy in children with cow's milk allergy manifested with atopic dermatitis.

There is increasing consensus about the significance of food allergens in the pathogenesis of atopic dermatitis (AD) in infancy and childhood, with cow's milk and egg accounting for most of the reactions. Previous studies have indicated that multiple food sensitization, such as cereals, is very common in patients with cow's milk allergy (CMA). Evidence is lacking, however, as to its clinical relevance. The purpose of this study was to determine the concurrent occurrence of cereal allergy among children with challenge-proven CMA who have residual symptoms, such as AD and/or gastrointestinal symptoms, during cow's milk elimination diet. Further, we sought to evaluate the utility of patch testing in prescreening foods other than cow's milk behind allergic symptoms in children. The study population comprised 90 children, aged from 2.5 to 36 months (mean 1.1 years), with challenge-proven CMA. As a result of residual symptoms during meticulous cow's milk elimination diet (AD: n=80, and gastrointestinal: n=10), the children were put on a cereal elimination diet (oats, wheat, rye, and barley) and skin prick tests (SPT) and patch testing with cereals were performed. Open cereal challenge was performed to confirm cereal allergy. Cereal challenge was positive in 66 (73%) of the children with CMA. Of them, 17% reacted with immediate reactions and delayed-onset reactions were seen in 83% of the children. SPT was positive in 23%, patch test in 67%, and either SPT or patch test was positive in 73% of the children with cereal allergy. SPT gave the best positive predictive value, whereas SPT together with patch test gave the best negative predictive value. Residual symptoms, such as eczema or gastrointestinal symptoms in CMA children may be a sign of undetected allergy to other food antigens. SPT with cereals aids in diagnosing cereal allergy in small children, especially when used together with patch testing.

The usefulness of patch testing on the previously most severely affected site in a cutaneous adverse drug reaction to tetrazepam

The usefulness of patch testing on the previously most severely affected site in a cutaneous adverse drug reaction to tetrazepam

Dermatitis to captopril

reports on delated cutaneous reactions to captopril have been seldom reported. Captopril is an angiotensin-converting enzyme (ACE) inhibitor and their cutaneous side-effects are documented, but little has been published concerning the usefulness of patch test when they occur. We presented the case of a patient who developed a cutaneous reaction induced by captopril with positive patch test. patch testing was performed with captopril, other ACE (enalapril, lisinopril ramipril), and European standard series. Following, we performed a double-blind oral challenge test with drugs who results was negative. Positive reaction were obtained to captopril at 4 days and the others test being negative. The same test were negative in five control patients. The patient tolerated enalapril, and lisinopril without problems. the allergological studies confirmed sensitisation to captopril and tolerance to lisinopril, and enalapril. When patch test are performed with several drugs of the same family, results seem to indicate an absence of cross-sensitivity, but in several patients, oral provocation test were needed because patch test gave no conclusive information.

North American Contact Dermatitis Group patch test results for the detection of delayed-type hypersensitivity to topical allergens

Background: Allergic contact dermatitis is a significant cause of cutaneous disease affecting many individuals. Patch testing, when used properly, often provides support for the diagnosis of allergic contact dermatitis. Objective: This article reports patch testing results from July 1, 1994, to June 30, 1996, by the North American Contact Dermatitis Group (NACDG). Methods: Patients evaluated in our patch test clinics were tested with the same screening series of allergens by the use of a standardized patch testing technique. The data from these patients were recorded on a standard computer entry form and analyzed. Results: Forty-nine allergens were tested on 3120 patients. Budesonide was added to the series in July 1995 and tested on 1678 patients. Of these patients, 66.5% had positive allergic patch test reactions, and 57% had at least one allergic reaction that was felt to be clinically relevant to the present or past dermatitis. The 20 screening allergens commercially available to United States dermatologists in the Allergen Patch Test Kit, accounted for only 54.1% of the patients with positive allergic reactions. The additional 30 allergens on the NACDG screening series accounted for 47% of patients with positive allergic reactions. Had the Allergen Patch Test Kit alone been used, 12.4% of all patients tested may have had their disease misclassified as a nonallergic disorder, and an additional 34.4% of all tested patients would not have had their allergies fully defined. Among those patients with positive responses to the supplemental allergens, 81% of the responses were of present or past relevance. The 12 most frequent contact allergens were nickel sulfate, fragrance mix, thimerosal, quaternium-15, neomycin sulfate, formaldehyde, bacitracin, thiuram mix, balsam of Peru, cobalt chloride, para-phenylenediamine, and carba mix. The present relevance varied with the specific allergen from 10.7% (thimerosal) to 85.7% (quaternium-15). Among newer allergens, methyldibromoglutaronitrile/phenoxyethanol (cosmetic preservative) caused positive allergic reactions in 2% of the patients; tixocortol-21-pivalate and budesonide (corticosteroids), in 2.0% and 1.1% of the patients, respectively; and ethylene urea/melamine formaldehyde mix (textile resin), in 5% of the patients. Conclusion: The usefulness of patch testing is enhanced with the number of allergens tested, because allergens not found on the commercially available screening series in the United States frequently give relevant allergic reactions. (J Am Acad Dermatol 1998;38:911-8.)

Patch testing in cutaneous reactions caused by carbamazepine

The usefulness of patch testing in the diagnosis of carbamazepine-induced allergic skin eruptions was studied in 18 patients with previous histories of skin eruptions caused by carbamazepine. The etiological role of carbamazepine was ascertained by peroral or topical provocation in 15 (out of 18) patients. The clinical reactions caused by the drug were classified as maculopapular exanthema with general symptoms (7 patients), other type of exanthema (3), exfoliative dermatitis (erythroderma) (3), fixed drug eruption (3), erythema multiforme (1) and urticaria (1). Patch testing showed positive reactions to carbamazepine in 7 patients; in addition, 2 patients had doubtful reactions. Positive patch test reactions were seen only in patients with exfoliative dermatitis (all 3 patients) and maculopapular exanthema (4 out of 7). None of the patients with fixed drug eruption, erythema multiforme or urticaria, or the control subjects, had positive patch test reactions to carbamazepine. The present study suggests that patch testing is useful in the diagnosis of carbamazepine allergy in patients with maculopapular eruptions or erythrodermas.

Dermatitis in Machinists: A Retrospective Study

Background: Over the years, studies have been performed to analyze contact dermatitis in metalworkers. Results for industrial workers in general have shown that about 25% clear, 50% improve, and 25% do no better or worsen. This retrospective study looked at the machinists who were treated in the occupational dermatology clinic at the Hershey Medical Center to evaluate their presentation, patch test results, diagnosis, and prognosis. In addition, we looked at the usefulness of patch testing in the subjects' outcome. A total of 20 machinists' charts were reviewed. Results: Five workers had allergic contact dermatitis, five had irritant contact dermatitis, four had endogenous dermatitis, and six had mixed dermatitis. Conclusions: We found that 25% of our workers cleared (5 of 20), 55% improved (11 of 20), and 20% were unable to be reached to further evaluate their prognosis (4 of 20). The results of patch testing seemed to have aided the improvement or clearance of dermatitis in seven cases.

Dermatitis in Machinists: A Retrospective Study

Background: Over the years, studies have been performed to analyze contact dermatitis in metalworkers. Results for industrial workers in general have shown that about 25% clear, 50% improve, and 25% do no better or worsen. This retrospective study looked at the machinists who were treated in the occupational dermatology clinic at the Hershey Medical Center to evaluate their presentation, patch test results, diagnosis, and prognosis. In addition, we looked at the usefulness of patch testing in the subjects' outcome. A total of 20 machinists' charts were reviewed. Results: Five workers had allergic contact dermatitis, five had irritant contact dermatitis, four had endogenous dermatitis, and six had mixed dermatitis. Conclusions: We found that 25% of our workers cleared (5 of 20), 55% improved (11 of 20), and 20% were unable to be reached to further evaluate their prognosis (4 of 20). The results of patch testing seemed to have aided the improvement or clearance of dermatitis in seven cases.