Results of patch testing in 10 patients with peristomal dermatitis.

BACKGROUND: Peristomal dermatitis is a common problem in patients with ostomies that is a source of considerable morbidity. Irritant contact dermatitis is most common, but allergic contact dermatitis can also occur. Because of the lack of published reports on patch testing for this indication, we undertook a retrospective study of patch testing results in patients with suspected peristomal allergic contact dermatitis. OBJECTIVE: We sought to describe our patch testing experience with patients referred with peristomal dermatitis. METHODS: This was a retrospective review of medical records of patients with ostomies and peristomal dermatitis who underwent patch testing in the Mayo Clinic Departments of Dermatology in Jacksonville, FL; Rochester, MN; and Scottsdale, AZ, during a 10-year period (2000-2010). RESULTS: Ten patients with peristomal dermatitis were referred for patch testing (6 in Minnesota, 2 in Florida, and 2 in Arizona). Patients were patch tested to the materials used in their stoma devices, to the standard series, and in some cases to supplemental series. All 10 had at least one allergic patch test reaction, most commonly to stoma paste (3 of 10 patients). LIMITATIONS: Retrospective nature of study via chart review is a limitation. CONCLUSION: Patch testing is a useful tool for identification of allergens in patients with peristomal dermatitis.

Delayed patch test reading after 5 days: the Mayo Clinic experience.

BACKGROUND: Some patients may have delayed allergic patch test reactions that are not identified with a typical 5-day reading protocol. OBJECTIVE: To identify allergens with delayed-positive reactions and to determine whether a late reading (day 7-9) can be substituted for the day-5 reading. METHODS: We retrospectively reviewed medical records of patients who underwent patch testing for suspected allergic contact dermatitis from October 1997 through December 2006 and returned for delayed readings between days 7 and 10 or beyond. (This cohort was predominantly patients with suspected allergies to metals and corticosteroids). RESULTS: A total of 36,064 individual reactions (471 allergens, 372 patients) were interpreted on day 5 and at least once during days 7 through 21. We analyzed the 170 allergens that were each tested in at least 50 patients. The 4 allergens with the highest percentage of delayed-positive reactions were gold sodium thiosulfate 0.5% (delayed-positive reactions in 22/353 patients), dodecyl gallate 0.25% (6/105), palladium chloride 2% (8/194), and neomycin sulfate 20% (10/253). We observed a low number of delayed-positive readings for p-phenylenediamine 1% (1/251) and for corticosteroids. Reactions to certain preservative and fragrance allergens dissipated after the day-5 reading. Most reactions that dissipated after day 5 were mild, whereas the reactions that became apparent after day 5 were strong. LIMITATIONS: This was a retrospective study. Most patients had suspected allergies to metals and corticosteroids. CONCLUSION: Late patch test readings (day 7 or beyond) were useful when interpreting reactions to metals and topical antibiotics, but it was not useful in the diagnosis of reactions to other allergens, including topical corticosteroids. Because reactions to certain fragrance and preservative allergens may dissipate after 5 days, patch test reactions therefore are optimally read at days 3 and 5, but an additional reading on day 7 or beyond is useful if patch tests to metals and topical antibiotics are performed.

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.

Low yield for extended reading of patch tests with topical corticosteroids.

BACKGROUND: On the basis of reports that up to 30% of patch test reactions are missed if an extended reading is not performed, we required that patients who were being patch tested with the corticosteroid series return for a reading at least 1 week after placement of the allergens. OBJECTIVE: To report our institutional experience with extended readings (day 7 or beyond) of patch test reactions to the corticosteroid series. METHODS: We retrospectively reviewed patch test reactions to corticosteroids since extended readings were implemented (April 2001 to June 2004). RESULTS: A total of 135 patients were patch tested with 1,656 corticosteroid allergens. On day 5, five patients had five positive patch test reactions; by the time of the extended reading, no new reactions had developed in these patients. Of the patients with no reactions on day 5, two had a positive result at the extended reading: each had a relevant reaction to budesonide 0.1%, one on day 7 and the other on day 9. CONCLUSIONS: Only 2 reactions (to 1,656 corticosteroids) became apparent at the extended reading. Extended readings were of limited value in our experience.

Patch testing with textile allergens: the mayo clinic experience.

BACKGROUND: Recognition of allergic contact dermatitis attributed to textile dyes and resins is steadily increasing. OBJECTIVE: This study aims to review the results of patch testing with a textile series at our institution and to compare with previously published reports. METHODS: We performed a retrospective review of results in patients who underwent patch testing using a series of textile dyes and resins from January 1, 2000, through September 30, 2011. RESULTS: A total of 671 patients (mean age, 56.5 years; female, 65.9%) were patch tested with the textile series (42 dyes and resins). These patients were also generally tested with the standard patch test series (n = 620). Of the patients, 219 (32.6%) demonstrated allergic reaction to 1 or more textile dyes and resins, and 71 (10.6%) manifested irritant reactions. The most frequent allergens were disperse blue 106 1% (8.3%), disperse blue 124 1% (8.0%), and melamine formaldehyde 7% (8.0%). Of patients tested with the standard series, 36 (5.8%) showed a positive reaction to the traditional textile screening allergen p-phenylenediamine 1%. CONCLUSIONS: Supplementing the standard series with the textile series increased detection of textile allergies. In patients suspected of textile allergy, addition of the textile series is necessary for appropriate diagnosis.

Patch-testing with hairdressing chemicals.

BACKGROUND: Hairdressing chemicals may be associated with allergic contact dermatitis. OBJECTIVE: To review our experience of patch-testing with hairdressing chemicals. METHODS: We reviewed results from patients who underwent patch testing with our standard allergen series (including 15 hairdressing chemicals) and a supplementary "hairdresser series" (18 additional hairdressing chemicals) at Mayo Clinic (Rochester, MN; Scottsdale, AZ; and Jacksonville, FL) from January 1, 2000, through December 31, 2008. RESULTS: Two hundred ten patients (mean age, 53.8 years [SD, 16.9 yr]; female, 94.8%) were patch-tested. The most common sites of dermatitis were the scalp, face, and hands. Patients had widely varying occupations. The most common occupations were cosmetologist (10.5%), housewife (9.5%), and beautician (5.2%); 14.3% were retired. The hairdresser series detected 13 additional patients with allergies (6.4%; 204 patients tested with both series) who would not have been detected with the standard allergen series alone. The highest allergic patch-test rates in the supplemental hairdresser series were with ammonium persulfate (14.4%), 4-aminoazobenzene (13.4%), and pyrogallol (9.1%). CONCLUSIONS: Patch-testing with hairdressing-specific chemicals (standard series plus supplemental hairdresser series) was appropriate for numerous clinical situations and was not limited to patients in hair care occupations. The supplemental hairdresser series helped identify more patients than would have been identified with the standard series alone.

Allergic contact dermatitis from exotic woods: importance of patch-testing with patient-provided samples.

Exotic woods from tropical and subtropical regions (eg, from South America, south Asia, and Africa) frequently are used occupationally and recreationally by woodworkers and hobbyists. These exotic woods more commonly provoke irritant contact dermatitis reactions, but they also can provoke allergic contact dermatitis reactions. We report three patients seen at Mayo Clinic (Rochester, MN) with allergic contact dermatitis reactions to exotic woods. Patch testing was performed and included patient-provided wood samples. Avoidance of identified allergens was recommended. For all patients, the dermatitis cleared or improved after avoidance of the identified allergens. Clinicians must be aware of the potential for allergic contact dermatitis reactions to compounds in exotic woods. Patch testing should be performed with suspected woods for diagnostic confirmation and allowance of subsequent avoidance of the allergens.

Patch testing with a large series of metal allergens: findings from more than 1,000 patients in one decade at Mayo Clinic.

BACKGROUND: The standard allergen series used in patch testing contains metals that most commonly cause allergic contact dermatitis, but testing with additional metal allergens is warranted for select patients. OBJECTIVE: To report our experience with patch testing of metals. METHODS: We retrospectively analyzed outcomes of 1,112 patients suspected of having metal allergies. Patients were seen from January 1, 2000, through December 31, 2009. Patch testing was performed with 42 metal preparations (6 in the standard series, 36 in the metal series). RESULTS: Patch testing most commonly was performed for patients with oral disease (almost half the patients), hand dermatitis, generalized dermatitis, and dermatitis affecting the lips, legs, arms, trunk, or face. At least one positive reaction was reported for 633 patients (57%). Metals with the highest allergic patch-test reaction rates were nickel, gold, manganese, palladium, cobalt, Ticonium, mercury, beryllium, chromium, and silver. Metals causing no allergic patch-test reactions were titanium, Vitallium, and aluminum powder. Metals with extremely low rates of allergic patch-test reactions included zinc, ferric chloride, and tin. Reaction rates varied depending on metal salt, concentration, and timing of readings. CONCLUSION: Many metals not in the standard series were associated with allergic patch-test reactions. The many questions raised by these findings, concerning patch testing with individual metals, will be the subject of future studies.

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.

The hazards of moist toilet paper: allergy to the preservative methylchloroisothiazolinone/methylisothiazolinone.

BACKGROUND: Methylchloroisothiazolinone/methylisothiazolinone (MCI/MI), a common preservative in some brands of moist toilet paper (baby wipes and moist towelettes), has been reported to be a cause of allergic contact dermatitis. However, few cases have been reported in the United States. OBSERVATIONS: We report the cases of 4 adult patients with severe perianal and perineal allergic contact dermatitis seen at our institution during a 6-month period. With patch testing, we identified allergy to MCI/MI, and we determined that all 4 patients were using moist toilet paper. The dermatitis resolved after use of the moist toilet paper was discontinued. CONCLUSION: This study highlights that the MCI/MI in moist toilet paper can be a cause of perianal and perineal allergic contact dermatitis.

A localized flare of dermatitis may render patch tests uninterpretable in some patients with recently controlled widespread dermatitis.

BACKGROUND: Patch testing rarely is confounded by localized dermatitis induced in the area being tested (usually the back). Its occurrence renders the interpretation of patch tests impossible. OBJECTIVE: To review our experience of the circumstances in which this phenomenon occurs during patch testing. METHODS: We retrospectively reviewed patients with this phenomenon who underwent patch testing from January 1, 2002, through June 30, 2006. RESULTS: Of the 3,569 patients tested, 12 (0.34% [9 men and 3 women]) had development of this phenomenon. All patients previously had recent widespread dermatitis that was suppressed temporarily with topical corticosteroids and wet dressings at the time of patch testing. The period between control of the dermatitis and the initiation of patch testing was less than 1 week for all patients. Three patients (25%) had recently discontinued therapy with systemic corticosteroids (less than 1 week earlier). CONCLUSION: In patients with irritable skin either immediately after widespread dermatitis is controlled or after the cessation of systemic corticosteroid treatment, a flare of dermatitis induced by patch testing may render patch tests unreadable and therefore uninterpretable. To avoid this confounding occurrence, a waiting period between control of widespread dermatitis and initiation of patch testing is advised.

Retrospective evaluation of patch testing before or after metal device implantation.

OBJECTIVE: To review the results of patch testing before or after metal device implantation. DESIGN: Retrospective medical chart review. SETTING: Tertiary care academic medical center. PATIENTS: All patients who underwent patch testing before or after metal device implantation. INTERVENTIONS: Patch testing. RESULTS: From January 1999 through March 2006, 44 patients underwent patch testing in conjunction with metal device implantation, 22 preoperatively and 22 postoperatively. The reason for preoperative patch testing was a history of allergy to metals. Five patients had positive results for a component of the proposed device. The reasons for postoperative patch testing were unexplained skin eruptions at the implantation site (13 patients), chronic joint pain (8 patients), and joint loosening (1 patient). None of the patients had positive patch test results to a component of the previously implanted device. CONCLUSIONS: Although the numbers of patients in this study were small, patch testing performed before metal device implantation was helpful in guiding the choice of device selected. Patch testing after implantation was of limited value.

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.

Rate of patch test reactions to a Dermatophagoides mix currently on the market: a mite too sensitive?

BACKGROUND: There long has been debate over the role of the dust mite antigen Dermatophagoides in provoking or perpetuating atopic and other forms of dermatitis, particularly airborne contact dermatitis. Reactivity to Dermatophagoides has been measured by specific IgE and by immediate-type responses to prick test challenge. More recently, patch testing has been advocated as a means of determining reactivity to Dermatophagoides. OBJECTIVE: To determine patch test reactivity to a Dermatophagoides mix in a population receiving patch testing. METHODS: A commercially available mix of 2 species of Dermatophagoides, Dermatophagoides pteronyssinus and Dermatophagoides farinae, recently became available. The authors chose the lower available concentration of this mix (20%) and added it to their standard patch testing tray between December 1999 and January 2001. Results were interpreted in the standard manner. RESULTS: A total of 662 patients received patch testing to Dermatophagoides (men 32%, women, 68%). Mean age was 53.4 years (range, 37 to 94). The Dermatophagoides mix was the most common allergen in the standard tray to evoke a reaction. At 96 hours, positive reactions were noted in 55% of patients. The reactions were interpreted as irritant in 16.2%, relevant in 6.7%, of questionable relevancy in 30.5%, and of no relevancy in 32.6%. The majority of reactions were of the "crescendo" pattern. CONCLUSION: The currently available formulation of Dermatophagoides mix, even at its lower concentration, led to a high rate of reactivity with a low rate of relevance.