Robert L. Rietschel

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.

North American Contact Dermatitis Group patch-test results, 2001-2002 study period.

Background: 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. Objective: This study reports the results of patch testing from January 1, 2001, to December 31, 2002, by the North American Contact Dermatitis Group (NACDG). Methods: 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. Results: 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. Conclusion: 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-test results of the North American Contact Dermatitis Group 2005-2006.

Background The North American Contact Dermatitis Group (NACDG) tests patients who have suspected allergic contact dermatitis with a broad series of screening allergens, and publishes periodic reports of its data. Objective To report the NACDG patch‐test results from January 1, 2005, to December 31, 2006, and to compare results to pooled test data from the previous 10 years. Methods Standardized patch testing with 65 allergens was used at 13 centers in North America. Chi‐square statistics were utilized for comparisons with previous NACDG data. Results NACDG patch‐tested 4,454 patients; 12.3% (557) had an occupation‐related skin condition, and 65.3% (2,907) had at least one allergic patch‐test reaction. The 15 most frequently positive allergens were nickel sulfate (19.0%), Myroxilon pereirae (balsam of Peru, 11.9%), fragrance mix I (11.5%), quaternium‐15 (10.3%), neomycin (10.0%), bacitracin (9.2%), formaldehyde (9.0%), cobalt chloride (8.4%), methyldibromoglutaronitrile/phenoxyethanol (5.8%), p‐phenylenediamine (5.0%), potassium dichromate (4.8%), carba mix (3.9%), thiuram mix (3.9%), diazolidinylurea (3.7%), and 2‐bromo‐2‐nitropropane‐1,3‐diol (3.4%). As compared to the 1994‐2004 data, there were significant increases in rates of positivity to nickel, quaternium‐15, potassium dichromate, lidocaine, and tea tree oil. Of patch‐tested patients, 22.9% (1,019) had a relevant positive reaction to a supplementary allergen; 4.9% (219) had an occupationally relevant positive reaction to a supplementary allergen. Conclusion Nickel has been the most frequently positive allergen detected by the NACDG; rates significantlyincreased in the current study period and most reactions were clinically relevant. Other common allergens were topical antibiotics, preservatives, fragrance mix I and paraphenylenediamine. Testing with an expanded allergen series and supplementary allergens enhances detection of relevant positive allergens.

Finasteride in the treatment of men with frontal male pattern hair loss

BACKGROUND Finasteride, a specific inhibitor of type II 5alpha-reductase, decreases serum and scalp dihydrotestosterone and has been shown to be effective in men with vertex male pattern hair loss. OBJECTIVE This study evaluated the efficacy of finasteride 1 mg/day in men with frontal (anterior/mid) scalp hair thinning. METHODS This was a 1-year, double-blind, placebo-controlled study followed by a 1-year open extension. Efficacy was assessed by hair counts (1 cm2 circular area), patient and investigator assessments, and global photographic review. RESULTS There was a significant increase in hair count in the frontal scalp of finasteride-treated patients (P < .001), as well as significant improvements in patient, investigator, and global photographic assessments. Efficacy was maintained or improved throughout the second year of the study. Finasteride was generally well tolerated. CONCLUSION In men with hair loss in the anterior/mid area of the scalp, finasteride 1 mg/day slowed hair loss and increased hair growth.

North American Contact Dermatitis Group Patch-test Results, 1998 to 2000

BACKGROUND Patch testing is the most worthwhile diagnostic tool for the evaluation of patients with suspected allergic contact dermatitis. OBJECTIVE This study reports patch-testing results from July 1, 1998, to December 31, 2000, by the North American Contact Dermatitis Group. METHODS Patients were tested with the same screening series of allergens, using a standardized patch-testing technique. The data from these patients were recorded on a standard computer entry form and analyzed. RESULTS Fifty allergens were tested on over 5,800 patients. Amidoamine, benzophenone-3, and iodopropynyl butylcarbamate were the new allergens. The top 10 allergens in frequency of positive reactions were identical to those of our 1996-to 1998-study period. The incidence of allergic nickel reactions continues to go up, leading all the test substances by 16.2%. CONCLUSION Our findings reinforce the need for a more comprehensive group of diagnostic allergens than is found in the T.R.U.E. TEST, which is sold in the United States.

Clinical dose ranging studies with finasteride, a type 2 5α-reductase inhibitor, in men with male pattern hair loss

BACKGROUND Androgenetic alopecia is a common condition of adult men. Finasteride, a type 2 5alpha-reductase inhibitor, decreases the formation of dihydrotestosterone from testosterone. OBJECTIVE Two separate clinical studies were conducted to establish the optimal dose of finasteride in men with this condition. METHODS Men from 18 to 36 years of age with moderate vertex male pattern hair loss received finasteride 5, 1, 0.2, or 0.01 mg/day or placebo based on random assignment. Efficacy was determined by scalp hair counts, patient self-assessment, investigator assessment, and assessment of clinical photographs. Safety was assessed by clinical and laboratory measurements and by analysis of adverse experiences. RESULTS Efficacy was demonstrated for all end points for finasteride at doses of 0.2 mg/day or higher, with 1 and 5 mg demonstrating similar efficacy that was superior to lower doses. Efficacy of the 0.01 mg dose was similar to placebo. No significant safety issues were identified in the trials. CONCLUSION Finasteride 1 mg/day is the optimal dose for the treatment of men with male pattern hair loss and was subsequently identified for further clinical development.

The cost of initiating appropriate therapy for skin diseases: A comparison of dermatologists and family physicians

A prospective survey examining how forty-one dermatologists and forty-one family practitioners manage patients with skin diseases was carried out in Atlanta, GA. The results show that dermatologists diagnose more conditions accurately, refer patients less often, charge more in professional fees, prescribe more medicines at higher cost to the patient but order laboratory tests costing less than do family physicians. More appropriate treatment was prescribed for nine of ten diseases by specialists compared to generalists. This limited study provides data which suggests that dermatologists provide more appropriate care than family practitioners in the treatment of skin diseases at no greater cost.

Prevention of poison ivy and poison oak allergic contact dermatitis by quaternium-18 bentonite☆

BACKGROUND Poison ivy and poison oak are the most common causes of allergic contact dermatitis in North America. OBJECTIVE We investigated whether a new topical lotion containing 5% quaternium-18 bentonite prevents experimentally induced poison ivy and poison oak allergic contact dermatitis. METHODS A single-blind, paired comparison, randomized, multicenter investigation was used to evaluate the effectiveness and safety of quaternium-18 bentonite lotion in preventing experimentally induced poison ivy and poison oak allergic contact dermatitis in susceptible volunteers. One hour before both forearms were patch tested with urushiol, the allergenic resin from poison ivy and poison oak, 5% quaternium-18 bentonite lotion was applied on one forearm. The test patches were removed after 4 hours and the sites interpreted for reaction 2, 5, and 8 days later. The difference in reactions between treated and untreated patch test sites was statistically analyzed. RESULTS Two hundred eleven subjects with a history of allergic contact dermatitis to poison ivy and poison oak were studied. One hundred forty-four subjects had positive reactions to urushiol. The test sites pretreated with quaternium-18 bentonite lotion had absent or significantly reduced reactions to the urushiol compared with untreated control sites (p < 0.0001) on all test days. When it occurred, the reaction consistently appeared later on treated than on control sites (p < 0.0001). One occurrence of mild, transient erythema at the application site was the only side effect from the quaternium-18 bentonite lotion. CONCLUSION Quaternium-18 bentonite lotion was effective in preventing or diminishing experimentally produced poison ivy and poison oak allergic contact dermatitis.

North American Contact Dermatitis Group patch test results for 2007-2008.

BackgroundThe North American Contact Dermatitis Group (NACDG) tests patients with suspected allergic contact dermatitis to a broad series of screening allergens and publishes periodic reports. ObjectiveThe aims of this study were to report the NACDG patch-testing results from January 1, 2007, to December 31, 2008, and to compare results to pooled test data from the previous 2 and 10 years to analyze trends in allergen sensitivity. Methods and MaterialsStandardized patch testing with 65 allergens was used at 13 centers in North America. &khgr;2 analysis was used for comparisons. ResultsA total of 5085 patients were tested; 11.8% (598) had an occupationally related skin condition, and 65.3% (3319) had at least 1 allergic patch test reaction, which is identical to the NACDG data from 2005 to 2006. The top 15 most frequently positive allergens were nickel sulfate (19.5%), Myroxylon pereirae (11.0%), neomycin (10.1%), fragrance mix I (9.4%), quaternium-15 (8.6%), cobalt chloride (8.4%), bacitracin (7.9%), formaldehyde (7.7%), methyldibromoglutaronitrile/phenoxyethanol (5.5%), p-phenylenediamine (5.3%), propolis (4.9%), carba mix (4.5%), potassium dichromate (4.1%), fragrance mix II (3.6%), and methylchloroisothiazolinone/methylisothiazolinone (3.6%). There were significant increases in positivity rates to nickel, methylchloroisothiazolinone/methylisothiazolinone, and benzophenone-3. During the same period of study, there were significant decreases in positivity rates to neomycin, fragrance mix I, formaldehyde, thiuram mix, cinnamic aldehyde, propylene glycol, epoxy resin, diazolidinyl urea, amidoamine, ethylenediamine, benzocaine, p-tert-butylphenol formaldehyde resin, dimethylol dimethyl hydantoin, cocamidopropyl betaine, glutaraldehyde, mercaptobenzothiazole, tosylamide formaldehyde resin, budesonide, disperse blue 106, mercapto mix, and chloroxylenol. Twenty-four percent (1221) had a relevant positive reaction to a non-NACDG supplementary allergen; and 180 of these reactions were occupationally relevant. ConclusionsPeriodic analysis, surveillance, and publication of multicenter study data sets document trends in allergen reactivity incidence assessed in the patch test clinic setting and provide information on new allergens of relevance.

North American Contact Dermatitis Group patch-test results, 2003-2004 study period

Background: Allergic contact dermatitis is a significant cause of both occupational and non‐occupational skin disease. Patch testing is an important diagnostic tool for the determination of responsible allergens. Objective: This study reports the results of patch testing by the North American Contact Dermatitis Group from January 1, 2003, to December 31, 2004. Methods: At 13 centers in North America, patients were tested with the same screening series of 65 allergens, with a standardized patch‐testing technique. Data were recorded on standardized forms and manually verified and entered. Descriptive frequencies were calculated, and trends were analyzed with chi‐square statistics. Results: A total of 5,148 patients were tested. Of these, 3,432 (66.7%) had at least one positive reaction, 2,284 (44.4%) were ultimately determined to have primary allergic contact dermatitis, and 676 (13.1%) had occupation‐related skin disease. There were 9,762 positive allergic reactions. Compared to the previous reporting period (2001‐2002), allergies to nickel, budesonide, mercaptobenzothiazole, and paraben mix were at least 1.12 times more common (all p values < .03). Compared with the previous 8 years (1994‐2002), only the prevalence rates of allergies to nickel and budesonide were statistically significantly higher (p values < .003). Conclusion: Allergic contact dermatitis from nickel and budesonide may be increasing in North America. These results again underscore the value of patch‐testing with many allergens.