Davis, Mark D.P.

Background: Photopatch testing is important for diagnosing photoallergic contact dermatitis. Although results of photopatch testing have been presented from many European centers, there have been few reports of the results of photopatch testing in the United States. Objective: To review the Mayo Clinic’s recent experience with photopatch testing, identify common photoallergens, and compare our current and previous findings. Methods: We retrospectively reviewed records of patients who underwent photopatch testing at the Mayo Clinic between January 1, 2000, and December 31, 2005 (N=182). Results: Fifty-four patients (29.7%) had photoallergic contact reactions, and 29 (15.9%) had allergic contact reactions. The most common photoallergens were medications, sunscreen agents, fragrances, and antiseptics. Conclusion: Photopatch testing is the technique useful in identifying photoallergens. The series of allergens used must be constantly updated to reflect newly identified and outdated photoallergens. We present a 6-year experience with photopatch testing. Medications, sunscreen agents, fragrances, and antiseptics were the most frequently identified photoallergens.

Background: Allergic contact dermatitis from rubber chemicals is increasingly recognized. Objective: To review the results of patch testing with rubber allergens from January 1, 2000, through December 31, 2007. Methods: Patients who underwent patch testing with a specialized series of rubber allergens were identified. Results: In total, 773 patients (64.2% female; mean age, 48.6 years) were patch-tested with a rubber series (27 allergens), and 739 (95.6%) were concomitantly patch-tested with a standard allergen series. Commonly affected sites of dermatitis were the hand (49.7%), foot (15.9%), leg (12.0%), and arm (10.9%). The most common occupations were health care worker (16.3%) and homemaker (6.5%); 11.3% were retired. The rate of allergic reaction to at least one rubber allergen was 245 of 773 (31.7%). The allergens that most commonly yielded positive reactions were 4,4-dithiodimorpholine 1% (28/286 [9.8%]), thiuram mix (56/739 [7.6%]), and diphenylguanidine 1% (57/759 [7.5%]). Conclusion: Rubber is a frequent cause of allergic contact dermatitis. Patch testing with a rubber series improved the ability to diagnose allergic contact dermatitis caused by rubber.

Background: Delayed hypersensitivity reactions to natural rubber latex (NRL) have been recognized. These reactions may contribute to allergic contact dermatitis. We therefore have undertaken patch testing of patients with NRL if they are suspected to have allergic contact dermatitis to rubber. Objective: To review results of patch testing with NRL (January 1, 2000, through December 31, 2007). Methods: Patients suspected of having allergic contact dermatitis from rubber who underwent patch testing with NRL were identified retrospectively. For safety reasons, patients with immediate hypersensitivity to NRL were excluded from patch testing. Results: Of 148 patients patch-tested with NRL, 3 (2.0%) had an allergic patch-test reaction. Conclusions: NRL is as common a cause of allergic contact dermatitis as many of the other allergens included in a specialized rubber allergen series. Patients suspected to be allergic to rubber should be patch-tested with NRL (provided they do not have type 1 hypersensitivity to NRL).

Abstract: The recently published 2016 revision of the WHO classification of lymphoid neoplasms includes primary cutaneous acral CD8-positive T-cell lymphoma (PCATCL) as a provisional entity. This is a rare indolent lymphoma characterized by papules or nodules on the ear and a dermal infiltrate of CD8-positive T-lymphocytes with cytotoxic marker expression. A retrospective review of a single institutional experience with PCATCL identified 3 patients (mean age 54; range 49–62) with papules or nodules on the ear. Lesional biopsies demonstrated a dense diffuse dermal infiltrate of atypical lymphocytes with a Grenz zone in 2 cases and focal epidermotropism in 1 case. The atypical lymphocytes were predominantly CD3 and CD8 positive with expression of cytotoxic marker TIA1. Staging evaluation failed to reveal systemic disease. Two patients underwent local excision, and the third received local radiation therapy all with complete response and no disease recurrence at last follow-up 3 months (range 2–5 months). Our cases add to the existing limited literature on the clinical and histopathological features of PCATCL. We also performed an updated systematic literature view of the entity.

BACKGROUND Few reports describe squamous cell carcinoma (SCC) arising in hidradenitis suppurativa (HS). OBJECTIVE The 2 objectives were (1) to describe the clinical characteristics, pathologic findings, and postoperative outcomes of SCC in HS and (2) to assess whether human papillomavirus (HPV) is involved in the pathogenesis. MATERIALS AND METHODS Cases of SCC in HS were identified through institutional medical records (1976–2013) and the Rochester Epidemiology Project. Tumor specimens were assessed for HPV DNA/RNA with in situ hybridization. RESULTS Twelve patients were identified (11 Caucasians and 9 men). All SCCs involved gluteal, perianal, or perineal skin; 1 patient had, in addition, involvement of the vagina. Surgical excision was performed on all 12 patients, 4 of whom had a colostomy. Mean duration of HS before SCC development was 28.5 years (range, 15–53 years). Mean follow-up was 4.3 years after surgical excision. Seven of 12 patients followed had postoperative SCC recurrence. Squamous cell carcinoma caused death despite wide surgical excision in these 7 patients. Of the remaining 5 patients, 4 are unknown and 1 who did not recur had an in situ SCC (Bowen disease carcinoma). Squamous cell carcinoma was not associated with high-risk or low-risk HPV. CONCLUSION Invasive SCC arising in HS carries a high risk of death.

Background Patch testing to a standard (baseline) series of allergens is the screening tool used to identify culprit allergens in patients with contact dermatitis. The allergens and concentrations used in a standard series are constantly evolving to be most relevant to the patients being patch tested. Objective The aim of this study was to analyze the 2011–2015 patch test results of the Mayo Clinic standard series. Methods We retrospectively reviewed patch test reactions of standard series allergens from 2011 through 2015 and compared these results with the 2011–2012 and 2013–2014 North American Contact Dermatitis Group (NACDG) reports. Conclusions Of 2582 patients included, 1566 (60.7%) had at least 1 positive reaction, and 516 (20.0%) had at least 1 irritant reaction. The 15 allergens with the highest reaction rates (from highest to lowest) were nickel sulfate hexahydrate, methylisothiazolinone, Myroxylon pereirae resin, neomycin sulfate, cobalt (II) chloride hexahydrate, benzalkonium chloride, fragrance mix I, potassium dichromate, bacitracin, methylchloroisothiazolinone/methylisothiazolinone, carba mix, formaldehyde, p -phenylenediamine, quaternium-15, and methyldibromo glutaronitrile. Twelve (80%) of these allergens were also in the top 15 of the most recent NACDG report; the 3 allergens not in the NACDG top 15 allergens were potassium dichromate, benzalkonium chloride, and methyldibromo glutaronitrile (the latter 2 allergens are not included in their series).

AbstractHand, foot, and mouth disease (HFMD) is an enterovirus‐mediated condition that predominantly affects children under 5 years of age. The tendency for outbreaks to peak in warmer summer months suggests a relationship between HFMD and weather patterns. We reviewed the English‐language literature for articles describing a relationship between meteorological variables and HFMD. Seventy‐two studies meeting criteria were identified. A positive, statistically significant relationship was identified between HFMD cases and both temperature (61 of 67 studies, or 91.0%, reported a positive relationship) [CI 81.8–95.8%,P = 0.0001] and relative humidity (41 of 54 studies, or 75.9%) [CI 63.1–85.4%,P = 0.0001]. No significant relationship was identified between HFMD and precipitation, wind speed, and/or sunshine. Most countries reported a single peak of disease each year (most commonly early Summer), but subtropical and tropical climate zones were significantly more likely to experience a bimodal distribution of cases throughout the year (two peaks a year; most commonly late spring/early summer, with a smaller peak in autumn). The rising global incidence of HFMD, particularly in Pacific Asia, may be related to climate change. Weather forecasting might be used effectively in the future to indicate the risk of HFMD outbreaks and the need for targeted public health interventions.