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.

Desmoplastic nevus: An entity distinct from spitz nevus and blue nevus.

Desmoplastic (sclerotic) nevus is an infrequently reported poorly characterized benign melanocytic proliferation, with only 4 case series published to date. To better define this nevus, we examined the clinical and histologic features of 25 lesions. Desmoplastic nevus is seen in both children and adults and can be located on the face, trunk, or extremities. There is a female predominance. Clinically, it can resemble intradermal nevus, atypical nevus, melanoma, and pigmented basal cell carcinoma. These are generally small, symmetric, and well-circumscribed lesions, averaging 3.5 mm in diameter. The most distinctive features include predominantly compound growth, a zonal configuration with greater cellularity in the superficial portion of the lesion, and a mixture of melanocytic phenotypes including type A, B, and C nevus cells, ovoid and dendritic melanocytes, and Spitzoid melanocytes. A distinctive eosinophilic stroma which either resembles that of a dermatofibroma or neurofibroma is always present. Variable amounts of melanin pigment are found in both tumor cells and macrophages, but this is not a prominent feature. Mitotic activity is exceedingly rare (1 case), and pleomorphism is minimal. These lesions are distinct from typical compound nevus, Spitz nevus, epithelioid blue nevus, and desmoplastic melanoma, to which they are often compared. Strict application of these histologic features allows definitive diagnosis of desmoplastic nevus as a distinct form of a benign melanocytic nevus.

Results of patch testing to personal care product allergens in a standard series and a supplemental cosmetic series: an analysis of 945 patients from the Mayo Clinic Contact Dermatitis Group, 2000-2007.

BACKGROUND: Patch testing to a standard screening series of allergens in combination with supplemental cosmetic allergens is often used to diagnose allergic contact dermatitis due to personal care products. OBJECTIVE: To report results of patch testing to skin care product allergens contained in a standard series and a supplemental cosmetic series and to compare efficacy of this combined series in detecting positive reactions to personal care product allergens with the efficacy of various standard screening series. METHODS: Positive reaction rates to skin care product allergens were tabulated for patients who underwent patch testing to both standard and cosmetic series allergens at Mayo Clinic between 2000 and 2007. Data were compared with skin care allergens detected on standard screening series, including the thin-layer rapid use epicutaneous (TRUE) test. RESULTS: Of 945 patch-tested patients, 68.4% had at least one positive reaction and 47.3% had at least two positive reactions. Also, 49.4% of patients reacted to at least one preservative; 31.2% reacted to at least one fragrance/botanical additive. Compared with use of our standard series and cosmetic series, use of the TRUE test would have missed 22.5% of patients with preservative allergy, 11.3% with fragrance/botanical allergy, and 17.3% with vehicle allergy. LIMITATIONS: Various allergens tested over time, patch test reading by residents, and lack of confirmation of allergen in personal care products. CONCLUSION: Standard patch-test screening series miss a substantial number of patients with skin care product ingredient allergy.

Primary cutaneous B-cell lymphoma in a child.

Primary cutaneous B-cell lymphoma is a B-cell lymphoma of the skin with no evidence of extracutaneous involvement at the time of diagnosis. In this report, we describe an 8-year-old boy who presented with a firm, alopecic, skin-colored, smooth nodule over the right frontal scalp. Histological examination revealed a mid-to deep-dermal mononuclear lesion. Immunohistochemical staining revealed a B-cell population that was CD10(+), CD5(-), CD21(+), and bcl2(-). This pattern of reactivity is characteristic of primary cutaneous B-cell lymphoma of follicle-center subtype. To the best of our knowledge, this is the first report of this type of cutaneous lymphoma in a child.

Treatment of locally metastatic melanoma: a novel approach.

We report a case of an 83-year-old female with locally metastatic melanoma treated with imiquimod and tazarotene. The patient originally presented to our dermatology clinic with local metastases of malignant melanoma after having undergone multiple surgical procedures and adjuvant radiation therapy for disease recurrence. At this juncture, she refused further surgical management but was interested in topical therapy. A 4-week course of topical imiquimod therapy was initiated. As no clinical response was noted at the end of the treatment period, tazarotene cream was introduced. The patient experienced complete clinical clearance of the treated area after a 6-week course of combination imiquimod and tazarotene therapy. The rationale for using both medications will be discussed.

Delayed Patch-Test Reading After 5 Days: An Update From the Mayo Clinic Contact Dermatitis Group.

BACKGROUND: Patch-test readings after day 5 have previously been used to identify delayed reactions to metals and topical antibiotics. OBJECTIVE: The aims of this study were to identify allergens for which late readings (beyond day 5) would be most valuable and to compare our results with our previous study on delayed patch-test readings. METHODS: This was a retrospective study of 298 patients who underwent metal and corticosteroid series patch testing from January 1, 2007, through December 31, 2013. Patch-test readings were conducted on days 3 and 5 and at least once sometime between days 7 and 14. All reactions were examined at each reading. CONCLUSIONS: These results were concordant with our previous findings that additional readings after day 7 are particularly useful for identifying reactions to metals (gold, cobalt, beryllium, palladium), specific preservatives (dodecyl gallate, propolis), and the topical antibiotic neomycin. New delayed reactions to bacitracin, p-phenylenediamine, and topical corticosteroids were not seen in this cohort.

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.

Contact dermatitis in older adults: a review of the literature.

Contact dermatitis is a significant health problem affecting the elderly. Impaired epidermal barrier function and delayed cutaneous recovery after insult enhances susceptibility to both irritants and allergens. Exposure to more numerous potential sensitizers and for greater durations influences the rate of allergic contact dermatitis in this population. Medical co-morbidities, including stasis dermatitis and venous ulcerations, further exacerbate this clinical picture. However, while these factors tend to increase the degree of sensitization in the elderly, waning immunity can actually decrease such a propensity. This interplay of both intrinsic and extrinsic factors makes a generalization on trends for contact dermatitis in older adults challenging. The literature has varying reports on the overall incidence of allergic contact dermatitis with advancing age. Nevertheless, it does clearly show that sensitivity to topical medicaments increases with age. Irritant contact dermatitis studies are more consistent, with less reactivity (to irritants) in older compared with younger skin. Diagnosis of both irritant and allergic contact dermatitis is based on a thorough history, complete skin examination, and comprehensive patch testing. The mainstay of therapy is avoidance of the offending chemical substances and the use of topical along with systemic therapies, depending on the severity of the condition.