Poison Ivy, Oak, and Sumac Dermatitis: What Is Known and What Is New?

Poison ivy, poison oak, and poison sumac are the most common causes of clinically diagnosed allergic contact dermatitis in North America. Approximately 50% to 75% of the US adult population is clinically sensitive to poison ivy, oak, and sumac. We reviewed the botany and history of these plants; urushiol chemistry and pathophysiology, clinical features, and the prevalence of allergic contact dermatitis caused by these plants; and current postexposure treatment and preventive methods, including ongoing investigations in the development of a vaccine (immunotherapy). Although extensive efforts have been made to develop therapies that prevent and treat contact dermatitis to these plants, there lacks an entirely effective method, besides complete avoidance. There is a need for a better therapy to definitively prevent allergic contact dermatitis to these plants.

Urushiol Patch Test Using the T.R.U.E. TEST System.

BACKGROUND: Poison ivy, poison oak, and poison sumac are the most common causes of allergic contact dermatitis in North America. Although extensive efforts have been made to develop therapies that prevent and treat allergic contact dermatitis to these plants, there lacks an entirely effective method, besides complete avoidance. Efforts to develop a more effective preventive therapy, such as a vaccine, are ongoing. To accurately evaluate the efficacy of these new therapies, an appropriate assessment tool is needed. OBJECTIVE: The aim of this study was to evaluate the safety and appropriate doses of urushiol required for a patch test based on the hydrogel delivery system of the Thin-Layer Rapid Use Epicutaneous Patch Test. METHODS: Nine subjects were patch tested with various doses of urushiol and a negative control on day 0. Patch test sites were inspected for any local reaction on days 2, 4, 7, 14, and 21 after the initial exposure and graded by standard morphology. CONCLUSIONS: All 9 subjects did not have any significant adverse effects. The urushiol patch test using the hydrogel delivery method demonstrated urushiol sensitivity. All doses of urushiol resulted in a local reaction, and severity of reactions was correlated with dosage of urushiol used in the patch test.

Different concentrations and volumes of p-phenylenediamine in pet. (equivalent doses) are associated with similar patch test outcomes: a pilot study.

BACKGROUND: Concern about causing active sensitization when patch testing is performed with p-phenylenediamine (PPD) 1% pet. has led to a recommendation to use PPD 0.3% pet. as a potentially safer preparation. However, the dose per area of allergen delivered, and hence the risk of active sensitization, depend on the amount dispensed into the patch test chamber, which can vary widely. OBJECTIVE: To evaluate whether patch testing with equivalent doses of different concentrations of PPD in pet. is associated with similar outcomes. METHODS: Seventeen known PPD-sensitive subjects were patch tested with different volumes and concentrations of PPD in pet. that deliver the same allergen dose per unit area (6 mg of PPD 1% pet. and 20 mg of PPD 0.3% pet. in Finn Chambers®, both equivalent to ∼ 0.09 mg/cm2 ). RESULTS: Eleven patients (65%) had positive reactions to both doses; 4 patients (24%) had negative results [percentage agreement of 88% (15/17)]. One patient each had a positive reaction to only one dose. CONCLUSIONS: The 88% concordance suggests that dose per unit area is more important in determining reactions to allergens than the excipient volume dispensed. Patch testing with a smaller volume of 1% PPD may be a reasonable alternative to testing with 20 mg of 0.3% PPD.

Jewellery: alloy composition and release of nickel, cobalt and lead assessed with the EU synthetic sweat method.

BACKGROUND: Several studies have shown nickel and cobalt release from jewellery by using spot tests, but the metal composition of jewellery is largely unknown. OBJECTIVES: To evaluate the metal composition of a large worldwide sample of mainly inexpensive jewellery items, and investigate the release of nickel, cobalt and lead from a subsample by using EN 1811:1998-required methods. METHODS: A total of 956 metallic jewellery components were examined with X-ray fluorescence spectroscopy. A subsample of 96 jewellery items purchased in the United States were investigated for nickel, cobalt and lead release by the use of artificial sweat immersion and plasma optical emission spectroscopy. RESULTS: Eighteen elements were detected. The 10 most frequently occurring were, in order of frequency, copper, iron, zinc, nickel, silver, chromium, tin, manganese, lead, and cobalt. Release of nickel was noted from 79 of the 96 US samples (0.01-98 µg/cm(2) /week), release of cobalt from 35 samples (0.02-0.5 µg/cm(2) /week), and release of lead from 37 samples (0.03-2718 µg/cm(2) /week). CONCLUSIONS: We present here a comprehensive list of the most frequently encountered metals in jewellery and fashion accessories. Different allergenic and non-allergenic metals are utilized. We also report the frequent release of nickel, cobalt and lead from these objects, despite legislative restrictions.

Spectrometric analysis of mercury content in 549 skin-lightening products: is mercury toxicity a hidden global health hazard?

BACKGROUND: Cosmetic skin lightening is practiced worldwide. Mercury is a well-documented melanotoxin added to some lightening products. However, mercury can cause many dermatologic, renal, and neurologic problems. The Food and Drug Administration limits the amount of mercury in cosmetic products to trace amounts, 1 ppm. OBJECTIVE: The objective of this study was to quantitatively evaluate a large international sample of lightening products for mercury content, focusing on products available to US consumers either online or in stores. METHODS: A total of 549 skin-lightening products, manufactured in 32 countries, were purchased online in the United States, Taiwan, and Japan and in stores in the United States, China, Taiwan, Thailand, Japan, and Sri Lanka. Cosmetics were screened for mercury content above 200 ppm using a low-cost portable x-ray fluorescence spectrometer. RESULTS: Of the 549 tested products, 6.0% (n = 33) contained mercury above 1000 ppm. In all, 45% of mercury-containing samples contained mercury in excess of 10,000 ppm. Of lightening products purchased in the United States, 3.3% were found to contain mercury in excess of 1000 ppm. LIMITATIONS: Our study did not evaluate creams for other melanosuppressive ingredients. Only 1 sample of each product was tested. CONCLUSION: Our study confirms the national and global presence of mercury in skin-lightening products.

A contemporary Fischer-Maibach investigation: variations in patch test delivery systems and implications for standardization.

BACKGROUND: Standardization of patch testing has been difficult to achieve. OBJECTIVES: This study aimed to identify physical variations in patch test systems that could affect delivery of allergens. METHODS: We compared the volume, depth, and contact area of 21 patch test delivery systems. We also filled a variety of patch test systems with different volumes of liquid (ferrous chloride) and petrolatum (disperse blue) allergens to investigate coverage and extrusion. RESULTS: The depth of chambers varied from minimal to greater than 1 mm. Mean areas ranged from 50 to almost 350 mm2. In most chambers, even the largest volume of liquid (40 µL) seemed to be completely contained by each product's absorbent material. The amount of petrolatum required to provide 100% coverage ranged from 15 to 45 µL. The dose delivered, as defined by mg per cm2, varied more than 2-fold across the systems. CONCLUSIONS: There are considerable differences across various patch tests. Different patch test systems likely do not deliver the same dose of allergen if the same volume of excipient is applied. Appreciating the differences between different patch test systems may help refine recommendations for the amount of allergens that should be applied to different patch test systems.

The cost of nickel allergy: a global investigation of coin composition and nickel and cobalt release.

BACKGROUND: Nickel is widely used in coins; nickel may cause contact allergy and allergic contact dermatitis in those who handle them. OBJECTIVES: To investigate alloy use, coin composition and nickel and cobalt release for a worldwide selection of currently circulating coins. MATERIALS AND METHODS: Eight hundred and fifty coins of 361 different denominations or issues from 52 countries were collected and analysed with X-ray fluorescence spectrometry and nickel and cobalt spot tests. RESULTS: Copper-nickel was the most frequently identified coin alloy, being observed in 100 denominations (28%), followed by aluminium-bronze (62, 17%). In total, 239 denominations released nickel (28%). Coins from Bolivia, Brazil and Costa Rica did not release nickel. Fewer than one-third of the denominations or issues from China, India, the euro area and Indonesia released nickel. In the United States, the Russian Federation, Japan, and Mexico, one-third or more of the denominations released nickel. CONCLUSIONS: This worldwide selection of circulating coins covered countries with 75% of the world population, and shows that the majority of the world population lives in countries where coins release nickel. Pertinently, ∼ 40% of circulating coin denominations do not release nickel.

Assessment of nickel release from earrings randomly purchased in China and Thailand using the dimethylglyoxime test.

BACKGROUND: China and Thailand produce large amounts of jewellery that are sold domestically and abroad. OBJECTIVE: To identify nickel release and metal content in earrings purchased in China and Thailand. METHODS: A total of 557 earrings were randomly purchased from vendors in 11 markets located in Beijing, Chengdu, Bangkok, Patong Beach, and Hat Yai. Earrings were subjected to dimethylglyoxime (DMG) tests and 26 of the DMG negative earrings were further evaluated qualitatively for major and minor metal content using X-ray fluorescence spectrometry. RESULTS: A total of 314 Chinese earrings (31.5%) and 243 Thai earrings (29.2%) were DMG test positive. Three (11.5%) of 29 DMG negative earrings contained nickel as a major component; 7 (26.9%) of 29 DMG negative earrings contained nickel as a minor component. DISCUSSION: Excessive nickel release was frequent. This may contribute to the high prevalence of nickel allergy in both countries. Increased public education together with the adoption of a regulatory intervention in Thailand may be warranted. In China, enforcement of the 2002 Chinese National Standard GB 11887 may assist in reducing sensitization. These initiatives may eventually result in decreased morbidity among the Chinese and Thai citizens, but can potentially benefit recipient countries of these important earring producing countries.

Prevalence of type I natural rubber latex allergy among dental hygienists.

PURPOSE: Oral health care professionals have been shown to be at risk for developing a type I allergy to natural rubber latex (NRL). The objective of this study was to assess the prevalence of this allergy in dental hygienists. METHODS: Participants attending the 2000-2002 American Dental Hygienists' Association (ADHA) national meetings were screened for type I allergies to NRL using skin prick testing, symptom assessment, and health history. Participants were classified as positive for a type I NRL allergy based on their positive skin prick reactions to standardized NRL solutions. Risk factors and symptom assessments were based on a self-reported health history. RESULTS: Of the 582 ADHA participants who completed the screening and health history questionnaire, 4.8% (n=28) screened positive for a type I allergy to NRL (SPT-positive). These SPT-positive participants were significantly more likely to report an allergy to cross-reacting foods, plants, molds, and pollens, and to report reactions to rubber products. Participants screened SPT-positive were also significantly more likely to report a history of hives and respiratory symptoms after contact with natural rubber. CONCLUSION: Based on skin prick testing, the prevalence of a type I allergy to NRL in dental hygienists appears similar to that reported for other oral health care professionals and is greater than the general population. Educating dental hygienists about type I NRL allergy may help reduce prevalence and improve its management.

Occupation-related allergies in dentistry.

BACKGROUND: Allergies to natural rubber latex (NRL) were unknown in dentistry until 1987. That changed with the publication of a report documenting NRL-based anaphylaxis in a dental worker. This case and others prompted regulatory and manufacturing changes in rubber products and increased awareness throughout the profession. However, other common dental chemicals cause allergic reactions and irritation and often are handled with insufficient precautions. Although recognition of NRL allergy has improved, awareness of other potential allergens and irritants in dentistry still is limited. OVERVIEW: Recent research indicates that the prevalence of NRL protein allergy may be decreasing. In contrast, occupation-related dermatoses associated with other dental products may be more common. Encounters with bonding agents, disinfectants, rubber, metals and detergents can cause occupation-based irritant contact dermatitis and allergic contact dermatitis. These conditions may be found in more than one-quarter of dental and medical personnel. Therefore, dental-specific information about the recognition and management of allergic and irritant reactions is needed. CONCLUSIONS AND CLINICAL IMPLICATIONS: The prevalence of occupation-related dermatitis may be increasing in dentistry. Reducing exposure to potential irritants and allergens and educating personnel about proper skin care are essential to reversing this trend.

Occupational allergens in dentistry.

PURPOSE OF REVIEW: Dental professionals and their physicians frequently do not recognize, accurately diagnose or appropriately manage occupational allergies. Dental allergen identification, diagnostics and practical avoidance strategies are summarized in this review. RECENT FINDINGS: Methacrylates, natural rubber latex proteins, rubber glove allergens, and glutaraldehyde are the predominant allergens in dentistry. Reactions range from cell-mediated contact allergy to urticaria and occupational asthma. SUMMARY: Despite recent advances in allergen characterization and increased awareness of selected allergens, treatment of occupational allergies can be improved. Better information and improved cooperation between dental workers and their clinicians is needed.

Allergic contact dermatitis in dental professionals: effective diagnosis and treatment.

BACKGROUND: Like other health care workers, dental professionals are at risk of developing allergic contact dermatitis, or ACD, after exposure to allergenic chemicals. Common allergens include antimicrobials, preservatives, rubber additives and methacrylates. CASE DESCRIPTION: The authors describe an orthodontic assistant with severe skin disease, whose symptoms included redness, cracking and bleeding that persisted for 10 years. The patient had previously received an incomplete diagnosis. After performing patch testing, assessing symptoms and evaluating the patient's medical history, the authors diagnosed ACD resulting from exposure to several dental allergens. The patient received appropriate treatment and counseling to better manage her allergies; this resulted in resolution of all symptoms and averted permanent occupational disability. CLINICAL IMPLICATIONS: Not all skin reactions are related to gloves or natural rubber latex. Dental professionals should be aware of common chemical allergens, symptoms of ACD and the appropriate treatment of occupational skin disease.

Management of dental patients with allergies to natural rubber latex.

Reports of serious allergic reaction to natural rubber latex (NRL) are not uncommon in dentistry. The prevalence of Type I allergies in high-risk patient groups can range as high as 17% for health care professionals and over 50% in patients with spina bifida. A Type IV allergy to NRL chemical additives, also known as allergic contact dermatitis, is common in health care professions. To safeguard patients and coworkers, dentists must learn to recognize patients and workers at risk for NRL allergies, identify the associated symptoms, implement preventive measures, and encourage thorough diagnostics and management. This article reviews the latest advances in NRL allergies, particularly as they apply in dentistry.