Trends in patch-test results and allergen changes in the standard series: a Mayo Clinic 5-year retrospective review (January 1, 2006, to December 31, 2010).

BACKGROUND: Patch testing is essential for identification of culprits causing allergic contact dermatitis. OBJECTIVE: We sought to identify trends and allergen changes in our standard series during 2006 to 2010, compared with our previous report (2001-2005). METHODS: We conducted a retrospective review of patch-test results. RESULTS: A total of 3115 patients were tested with a mean of 73.0 allergens. Since our prior report, 8 allergens were added to the standard series; 14 were deleted. Significantly higher rates of allergic positive reaction were documented for carba mix, 3%, and Disperse Orange 3, 1%. Rates were lower for 10 allergens: neomycin sulfate, 20%; gold sodium thiosulfate, 0.5%; hexahydro-1,3,5-tris(2-hydroxyethyl)triazine, 1%; disperse blue 124, 1%; disperse blue 106, 1%; diazolidinyl urea, 1%; hexylresorcinol, 0.25%; diazolidinyl urea, 1% aqueous; 2-bromo-2-nitropropane-1,3-diol, 0.25%; and lidocaine, 5%. Many final patch-test readings for many allergens were categorized as mild reactions (erythema only). Overall allergenicity and irritancy rates declined significantly since our prior report. Results were generally comparable with those in a North American Contact Dermatitis Group report from 2005 to 2006. LIMITATIONS: This was a retrospective study; there is a lack of long-term follow-up. CONCLUSIONS: Since our previous report, our standard series composition has changed, and overall rates of allergenicity and irritancy have decreased. Notably, many final patch-test readings showed mild reactions.

Pemphigus foliaceus with epidermal detachment: adverse events from patch testing.

Uncommon adverse reactions to patch testing have been reported, but few cases have shown patch testing to be a potential contraindication. We report a patient with known pemphigus foliaceus who had significant epidermal detachment of normal skin during the removal of patch-testing tape.

Pulse versus continuous terbinafine for onychomycosis: a randomized, double-blind, controlled trial.

BACKGROUND: Effective treatments for onychomycosis are expensive. Previous studies suggest that less costly, pulsed doses of antifungal medications may be as effective as standard, continuous doses. Terbinafine is the current treatment of choice for toenail onychomycosis. OBJECTIVE: Our purpose was to determine whether pulse-dose terbinafine is as effective as standard continuous-dose terbinafine for treatment of toenail onychomycosis. METHODS: We conducted a double-blind, randomized, noninferiority, clinical intervention trial in the Minneapolis Veterans Affairs Medical Center. The main inclusion criteria for participants were a positive dermatophyte culture and at least 25% distal subungual clinical involvement. Six hundred eighteen volunteers were screened; 306 were randomized. Terbinafine, 250 mg daily for 3 months (continuous) or terbinafine, 500 mg daily for 1 week per month for 3 months (pulse) was administered. The primary outcome measure was mycological cure of the target toenail at 18 months. Secondary outcome measures included clinical cure and complete (clinical plus mycological) cure of the target toenail and complete cure of all 10 toenails. RESULTS: Results of an intent-to-treat analysis did not meet the prespecified criterion for noninferiority but did demonstrate the superiority of continuous-dose terbinafine for: mycological cure of the target toenail (70.9% [105/148] vs 58.7% [84/143]; P =.03, relative risk [RR] of 1.21 [95% confidence interval (CI), 1.02-1.43]); clinical cure of the target toenail (44.6% [66/148] vs 29.3% [42/143]; P =.007, RR =1.52 [95% CI, 1.11-2.07); complete cure of the target toenail (40.5% [60/148] vs 28.0% [40/143]; P =.02, RR=1.45 [95% CI, 1.04-2.01); and complete cure of all 10 toenails (25.2% [36/143] vs 14.7% [21/143]; P =.03, RR =1.71 [95% CI, 1.05-2.79). Tolerability of the regimens did not differ significantly between the groups (chi2 =1.63; P =.65). LIMITATIONS: The study population primarily consisted of older men with severe onychomycosis. CONCLUSIONS: This study demonstrated the superiority of continuous- over pulse-dose terbinafine. We also found this expensive therapy to be much less effective than previously believed, particularly for achieving complete cure of all 10 toenails.

Patch test results from the Mayo Clinic Contact Dermatitis Group, 1998-2000.

BACKGROUND: Patch testing is a diagnostic tool for the evaluation of patients with suspected allergic contact dermatitis. A standard series of allergens similar to that used by the North American Contact Dermatitis Group (NACDG) is used at Mayo Clinic. OBJECTIVE: Our aim was to report the results of patch testing with a standard series at Mayo Clinic from July 1, 1998, to Dec 31, 2000 and to compare our findings with those of the NACDG during the same period. METHODS: The results of patch testing with the standard series at Mayo Clinic were examined. Positive reaction rates were compared between Mayo Clinic and the NACDG. RESULTS: During the 30-month period, 1324 Mayo Clinic patients were patch tested with a standard series of allergens (mean, 60 allergens), whereas the NACDG standard series during this period included 50 allergens. Overall, 917 patients (69.3%) had at least one positive reaction and 606 patients (45.8%) had two or more positive reactions. The 10 allergens used both by Mayo Clinic and by the NACDG that most frequently caused positive reactions were nickel sulfate hexahydrate, balsam of Peru (Myroxylon pereirae), neomycin sulfate, cobalt chloride, fragrance mix, potassium dichromate (0.25%), thimerosal, bacitracin, formaldehyde, and glutaraldehyde. Statistically significant differences in positive reaction rates (P < .05) were observed for 12 of the 43 allergens common to both Mayo Clinic and the NACDG. CONCLUSION: With large standard patch test series, one can identify commonly encountered and potentially relevant contact allergens.

Patch-test reactions to thioureas are frequently relevant.

BACKGROUND: Thioureas are used as antioxidants in the manufacture of rubber (especially neoprene) and as fixatives in photography and photocopy paper. The number of reported cases of allergic contact dermatitis from thioureas is relatively low, and standard patch test series often do not contain thiourea allergens. Thioureas are included in our institution's standard patch test series. OBJECTIVE: To examine the occurrence and relevance of patch-test reactions to thioureas. METHODS: We retrospectively analyzed patch-test data for patients evaluated between January 1999 and June 2001. Patients included in the study underwent testing with a standard screening series of allergens and a standardized patch testing technique. Our standard patch test series includes mixed dialkyl thioureas at a concentration of 1% in petrolatum. RESULTS: Of 1,368 patients tested with our standard series, 33 patients (2.4%) had patch-test reactions to mixed dialkyl thioureas at day 5. Reactions in 14 (42%) of those patients were of definite clinical relevance, indicating a confirmed exposure to thioureas in many different settings. CONCLUSION: Patch-test reactions to thioureas occur as often as do reactions to many other allergens in the standard series and are often relevant. Institutions should consider including mixed dialkyl thioureas in their standard patch test screening series.

Botanical briefs: Capsicum peppers.

Capsicum peppers are widespread, both in and out of the kitchen, both nationally and internationally. They contribute to burning and stinging of hands, mouth, and eyes in conjunction with food preparation and ingestion that is often unreported to the medical community. The literature is not abundant on the subject and often is confusing. This article provides brief yet detailed information about this important plant.

Patch test results may vary depending on where testing is performed: a comparison of patch test results from three geographically distinct sites in the USA.

BACKGROUND: Do patch test results vary from one part of the USA to another? Few reports directly compare the results of patch testing across centers within the USA. OBJECTIVES: Our objective was to compare results of patch testing from three geographically disparate Mayo Clinic sites in the USA to ascertain whether there are any differences in allergic patch test rates. METHODS: We retrospectively reviewed patch test results for patients tested with a standard allergen series using our enterprise-wide protocol for patch testing. We compared data collected from January 1, 2001, through to December 31, 2007, from our practice sites in the Midwest, Southwest, and Southeast regions of the USA. RESULTS: In total, 5063 patients underwent patch testing. The mean (standard deviation) number of allergens tested per patient was 70.3 (3.8) (range: 10-87; interquartile range: 68-73). Analyses were conducted separately for 72 allergens with positive reactions from at least 20 patients. Risk-adjusted positive reaction rates (RAPRRs) for 44 allergens differed significantly (P<0.05) among the geographic sites; RAPRRs differed significantly across all three sites for 11 allergens and between two of the three sites for 33 allergens. CONCLUSIONS: Allergic patch test rates differed among our three practice sites for many allergens. It is likely that many factors contributed to these observed differences, including variations in the population undergoing patch testing, variations in allergen exposure, and variations in climate.

Changing trends and allergens in the patch test standard series: a mayo clinic 5-year retrospective review, january 1, 2001, through december 31, 2005.

OBJECTIVE: To present and interpret results of patch testing with the Mayo Clinic standard series over 5 years. DESIGN: Retrospective study. A standardized patch testing technique was used. Data were recorded on a standardized computer program from January 1, 2001, to December 31, 2005, and analyzed. SETTING: Tertiary referral center. PATIENTS: Patients who were referred for patch testing. INTERVENTION: Patch testing with the "standard series," ie, a standard series of allergens used by most clinicians to identify the most common offending allergens in patients with allergic contact dermatitis. MAIN OUTCOME MEASURES: Number of patients patch tested, allergens used over this period, and rates of allergic patch test reactions to allergens. RESULTS: A total of 3854 patients (mean age, 55.1 years; age range, 6.2-99.4 years; 2576 female [66.8%]) were tested. All dermatologists in the department performed patch testing. The mean number of allergens included was 69.3 (range, 6-87). There were 2664 patients with at least 1 positive reaction (69.1%) and 1933 with 2 or more positive reactions (50.2%). Metals, fragrances, topical antibiotics, preservatives, and individual allergens used in hair-care products, topical corticosteroids, glues, plastics, and rubber were still the most common allergen groups associated with allergic patch test reactions. CONCLUSIONS: We describe the structure of the patch testing service at our referral center. Ongoing analysis of our patch test reaction rates allows us to recommend broad, clinically relevant, and up-to-date allergens for testing.