Contact sensitization to modern dressings: a multicentre study on 354 patients with chronic leg ulcers

Sensitization to Lanolin in North-Eastern Italy, 1997-2021: Prevalence, Risk Factors and the Impact of Occupation

Background: Direct skin contact with items containing lanolin can induce sensitization and development of contact dermatitis (CD). This multi-centric study investigated prevalence of lanolin sensitization among 30,269 outpatients from North-Eastern Italy patch tested during 1997-2021. Methods: European baseline and extended Triveneto series were applied on the upper part of patients' back and removed after 48 h. Risk factors for lanolin sensitization were investigated by multiple logistic regression analysis, reporting adjusted odds ratios (aOR) with 95% confidence interval (95%CI). Results. Overall lanolin patch test positive ratio (PTPR) was 1.64% (=501/30,629), with variability over time and by research center. The body area most frequently affected by CD were hands (36.32%), followed by face (19.52%) and legs (8.09%), with a lanolin PTPR of 1.68%, 1.37% and 3.07%, respectively. Prevalence of occupational CD was 8.24%, and 1.83% patients with occupational CD patch tested positive against lanolin. Lanolin sensitization was significantly higher in males (aOR = 1.34; 95%CI: 1.08; 1.65) and among patients with leg CD aged 49-60 years (aOR = 2.34; 95%CI: 1.20; 4.57) or older than 60 (aOR = 4.21; 95%CI: 2.59; 6.85). Sub-group analysis confirmed the significantly higher sensitization rate of older patients with leg CD, with much stronger effect size in females 61+ years old (aOR = 5.33; 95%CI 2.87; 9.89) than males in the same age group (aOR = 2.92; 95%CI: 1.34; 6.39). Moreover, female house painters were more likely to test positive to lanolin. Conclusions: The variability of lanolin PTPR over time and by research center endorsed the ongoing debate on the relevance of the respective skin reaction. Clinicians assessing patients with dermatitis should collect information on potential risk factors for lanolin sensitization, particularly use of skin care products containing the hapten. Occupational exposure to lanolin-containing varnishes should also be considered.

Sodium Dehydroacetate and Dehydroacetic Acid

The Expert Panel for Cosmetic Ingredient Safety (Panel) first published a safety assessment of Sodium Dehydroacetate and Dehydroacetic Acid in 1985. The Panel previously concluded that Sodium Dehydroacetate and Dehydroacetic Acid are safe as used in the present practices of use and concentration, as stated in that report. Upon re-review in 2003, the Panel reaffirmed the original conclusion, as published in 2006. The Panel reviewed updated frequency and concentration of use data again in 2023, in addition to any newly available, relevant safety data. Considering this information, as well as the information provided in the original safety assessment and the prior re-review document, the Panel reaffirmed the 1985 conclusion.

Polysensitization in the Spanish Contact Dermatitis Registry (REIDAC): A 2019-2022 prospective study with cluster and network analysis

BACKGROUND

There is still limited clinical-practice data on specific clinical and patch test features, as well as on allergen clusters in polysensitization (PS).

OBJECTIVES

To determine the frequency, relevance, symptoms duration and risk factors in polysensitized patients and to assess possible allergen aggregation.

METHODS

Prospective multicentric study (January 2019-December 2022) conducted in setting of the Spanish Contact Dermatitis Register (REIDAC). Clinical and patch test data of polysensitized and oligosensitized patients were compared, and risk factors of PS were investigated with logistic multivariate regression. Unsupervised hierarchical clustering and network analysis were used to study allergen aggregation in PS.

RESULTS

A total of 10,176 patients were analysed. PS was found in 844 (8.3%). Current relevance was significantly higher in polysensitized patients (p < 0.01). Risk factors for PS were atopic dermatitis (OR: 1.58, 95% CI: 1.24-2.02), age (≥60 years vs. ≤24 years, OR: 1.75, 95% CI: 1.25-2.44) and some special locations (legs vs. face OR: 1.54, 95% CI: 1.05-2.25, hands vs. face OR: 1.46, 95% CI:1.15-1.85, arms vs. face OR: 1.49, 95% CI:1.01-2.20, trunk vs. face OR: 1.40, 95% CI:1.06-1.85). Cluster and network analyses revealed specific-allergen clusters and significant associations, including allergens belonging to metals group, fragrances and botanicals group, topical drugs group, rubber allergens and biocides.

CONCLUSIONS

This study confirms that PS is structured by discernible patterns of specific-allergen clusters and reinforces significant allergen associations in PS. Cross-reactivity and/or concomitant sensitization could explain the formation of allergen clusters in PS.

Advances in tissue engineering and biofabrication for in vitro skin modeling

The global prevalence of skin disease and injury is continually increasing, yet conventional cell-based models used to study these conditions do not accurately reflect the complexity of human skin. The lack of inadequate in vitro modeling has resulted in reliance on animal-based models to test pharmaceuticals, biomedical devices, and industrial and environmental toxins to address clinical needs. These in vivo models are monetarily and morally expensive and are poor predictors of human tissue responses and clinical trial outcomes. The onset of three-dimensional (3D) culture techniques, such as cell-embedded and decellularized approaches, has offered accessible in vitro alternatives, using innovative scaffolds to improve cell-based models' structural and histological authenticity. However, these models lack adequate organizational control and complexity, resulting in variations between structures and the exclusion of physiologically relevant vascular and immunological features. Recently, biofabrication strategies, which combine biology, engineering, and manufacturing capabilities, have emerged as instrumental tools to recreate the heterogeneity of human skin precisely. Bioprinting uses computer-aided design (CAD) to yield robust and reproducible skin prototypes with unprecedented control over tissue design and assembly. As the interdisciplinary nature of biofabrication grows, we look to the promise of next-generation biofabrication technologies, such as organ-on-a-chip (OOAC) and 4D modeling, to simulate human tissue behaviors more reliably for research, pharmaceutical, and regenerative medicine purposes. This review aims to discuss the barriers to developing clinically relevant skin models, describe the evolution of skin-inspired in vitro structures, analyze the current approaches to biofabricating 3D human skin mimetics, and define the opportunities and challenges in biofabricating skin tissue for preclinical and clinical uses.

Sodium dehydroacetate-induced disorder of coagulation function in broiler chickens and the protective effect afforded by vitamin K

Sodium dehydroacetate (S-DHA) is used widely as a preservative in several products, including poultry feed. The anticoagulation effect of 200 mg/kg S-DHA in rats has been reported to accompany a reduction in hepatic expression of vitamin K epoxide reductase complex 1 (VKORC1). Poultry and mammals have different physiology and coagulation systems, and species differences in VKORC1 expression have been found. The effect of S-DHA on blood clotting of poultry has not been studies deeply. S-DHA was given to yellow-plumage broilers (YBs) as single and multiple administrations. Vitamin K3 (VK₃) was injected into YBs 2 wk after S-DHA administration. Then, the prothrombin time (PT), partial activated prothrombin time (APTT), plasma levels of vitamin K (VK), factor IX (FIX), and S-DHA, and hepatic expression of VKORC1 were obtained. Chicken hepatocellular carcinoma (LMH) cells were also exposed to S-DHA, and the cell activity, VK level, and FIX level were measured. S-DHA prolonged the PT or APTT significantly, decreased levels of VK and FIX in blood, and inhibited hepatic expression of VKORC1. The maximum changes were 1.15-fold in the PT, 1.42-fold in the APTT, 0.8-fold in the VK level, 0.7-fold in the FIX level, and 0.35-fold in VKORC1 expression compared with controls. The cell activity, VK level, FIX level, and VKORC1/VKORC1L1 expression of LMH cells were reduced significantly at S-DHA doses of 2.0 to 10.0 mM. Prolongation of the PT/APTT and lower levels of VK/FIX in YBs or the lower cell activity and VK/FIX levels in LMH cells induced by S-DHA therapy were resisted significantly by VK₃ treatment. We demonstrated that S-DHA could induce a disorder in coagulation function in YBs or in LMH cells via reduction of VKORC1/VKORC1L1 expression, and that VK could resist this anticoagulation effect.

Mechanism of VKORC1 and VKORC1L1 signaling in the effects of sodium dehydroacetate on coagulation factors in rat hepatocytes

Sodium dehydroacetate (Na-DHA) is widely used as an antibacterial and preservative additive in food and cosmetics. Previously, we reported that repeated oral administration of Na-DHA induces coagulation disorders, and inhibited liver vitamin K epoxide reductase complex subunit 1 (VKORC1) and VKORC1-like protein 1 (VKORC1L1) in rats. However, the effects of Na-DHA on coagulation factors in rat hepatocytes and the mechanism of VKORC1 and VKORC1L1 signaling in that process are unclear. Here, we constructed stable Vkorc1 and Vkorc1l1 overexpressing cell lines using lentiviruses and transfected small interfering RNAs into buffalo rat liver BRL3A cells for Vkorc1 and Vkorc1l1 overexpression and silencing, respectively. After treatment with 5 mmol/L Na-DHA for 24 h, VKORC1 and VKORC1L1 expression levels were detected by real-time PCR and western blotting. Vitamin K (VK) and factor IX (FIX) contents were detected using enzyme linked immunosorbent assays. We observed that Na-DHA inhibited VKORC1 and VKORC1L1 expression levels and reduced VK and FIX levels in rat hepatocytes. Overexpression or silencing of Vkorc1 and Vkorc1l1 increased or decreased, respectively, the production and secretion of VK and FIX in rat hepatocytes, and alleviated or aggravated the inhibitory effects of Na-DHA on VKORC1 and VKORC1L1 expression levels. Taken together, the results indicated that both VKORC1 and VKORC1L1 signaling play regulatory roles in the effects of Na-DHA on coagulation factors in rat hepatocytes.

Potential Allergens in Wound Care Products

Background: Patients with chronic wounds have an increased risk of developing allergic contact dermatitis (ACD). Reports of ACD to wound care products are not uncommon. To minimize contact sensitization in patients with chronic wounds, allergenic ingredients should be avoided when possible. Objective: With more than 5000 wound care products available in the United States, it is essential to understand which products can be chosen to minimize allergen exposures. Methods: Ingredients in wound care products in 5 wound care clinics across 2 institutions were cross-referenced with the American Contact Dermatitis Society core allergen series 2020. Results: Of the 267 wound care products included, 97 (36.3%) contained at least one allergen, including 31 dressings/wraps (22.3%), 25 medications (69.4%), 12 cleaning supplies (36.3%), 16 tapes/glues (80%), 2 instruments (14.3%), 8 emollients and vehicles (61.5%), 1 ostomy product (11.1%), and 2 odor-eliminating products (66.7%). Thirty-four different allergens were identified across all products. The most common allergens present in the included items were acrylates and propylene glycol, followed by parabens, cetyl stearyl alcohol, tocopherol, fragrance, and phenoxyethanol. Conclusions: Many wound care products contain at least one contact allergen, highlighting the importance of clinician education on ACD in the context of wound care product selection.

Lanolin

Lanolin is a complex mixture of high molecular weight esters, aliphatic alcohols, sterols, fatty acids, and hydrocarbons that has been widely used for centuries for its emollient properties. The purification of crude lanolin into lanolin wax and the processing of this wax into various derivatives began in 1882 and continue to this day with newer highly purified anhydrous lanolins. Controversy as to lanolin's allergenicity began in the 1920s and remains an issue. The most appropriate patch test preparation(s) for detecting allergy remain disputed. Detection of lanolin-induced contact dermatitis in diseased skin by patch testing on normal skin may lead to false negative results. Patients with a positive patch test to lanolin may tolerate use of lanolin on normal skin. Although lanolin is a weak sensitizer and the frequency of contact allergy to it in the European population reportedly is 0.4%, there are high-risk concomitant conditions: stasis dermatitis, leg ulcers, perianal/genital dermatitis, and atopic dermatitis (AD). Children and the elderly are also at greater risk of developing contact allergy to lanolin, partly because of comorbidities (AD and stasis dermatitis/leg ulcers, respectively). Finally, in the United States, non-Hispanic white patients are more likely than their non-Hispanic black counterparts to be lanolin allergic.

Potential Allergens in Wound Care Products

BACKGROUND

Patients with chronic wounds have an increased risk of developing allergic contact dermatitis (ACD). Reports of ACD to wound care products are not uncommon. To minimize contact sensitization in patients with chronic wounds, allergenic ingredients should be avoided when possible.

OBJECTIVE

With more than 5000 wound care products available in the United States, it is essential to understand which products can be chosen to minimize allergen exposures.

METHODS

Ingredients in wound care products in 5 wound care clinics across 2 institutions were cross-referenced with the American Contact Dermatitis Society core allergen series 2020.

RESULTS

Of the 267 wound care products included, 97 (36.3%) contained at least one allergen, including 31 dressings/wraps (22.3%), 25 medications (69.4%), 12 cleaning supplies (36.3%), 16 tapes/glues (80%), 2 instruments (14.3%), 8 emollients and vehicles (61.5%), 1 ostomy product (11.1%), and 2 odor-eliminating products (66.7%). Thirty-four different allergens were identified across all products. The most common allergens present in the included items were acrylates and propylene glycol, followed by parabens, cetyl stearyl alcohol, tocopherol, fragrance, and phenoxyethanol.

CONCLUSIONS

Many wound care products contain at least one contact allergen, highlighting the importance of clinician education on ACD in the context of wound care product selection.

Quaternary ammonium compounds in hypersensitivity reactions

Quaternary ammonium compounds (QAC) are commonly used disinfectants, antiseptics, preservatives, and detergents due to their antibacterial property and represent the first used biocides before phenolic or nitrogen products. Their common structure consists of one or more quaternary ammonium bound with four lateral substituents. Their amphiphilic structure allows them to intercalate into microorganism surfaces which induces an unstable and porous membrane that explains their antimicrobial activity towards bacteria, fungi, and viruses. QAC are thus found in many areas, such as household products, medicines, hygiene products, cosmetics, agriculture, or industrial products but are also used in medical practice as disinfectants and antiseptics and in health care facilities where they are used for cleaning floors and walls. QAC exposure has already been involved in occupational asthma in healthcare workers or professional cleaners by many authors. They also have been suggested to play a role in contact dermatitis (CD) and urticaria in workers using cosmetics such as hairdressers or healthcare workers, inciting reglementary agencies to make recommendations regarding those products. However, distinguishing the irritant or sensitizing properties of chemicals is complex and as a result, the sensitizing property of QAC is still controverted. Moreover, the precise mechanisms underlying the possible sensitization effect are still under investigation, and to date, only a few studies have documented an immunological mechanism. Besides, QAC have been suggested to be responsible for neuromuscular blocking agents (NMBA) sensitization by cross-reactivity. This hypothesis is supported by a higher prevalence of quaternary ammonium (QA)-specific IgE in the professionally exposed populations, such as hairdressers, cleaners, or healthcare workers, suggesting that the sensitization happens with structurally similar compounds present in the environment. This review summarizes the newest knowledge about QAC and their role in hypersensitivities. After describing the different QAC, their structure and use, the most relevant studies about the effects of QAC on the immune system will be reviewed and discussed.

The importance of periwound skin in wound healing: an overview of the evidence

DECLARATION OF INTEREST

The authors have no conflicts of interest.

Allergies and COVID-19 vaccines: An ENDA/EAACI Position paper

BACKGROUND

Anaphylaxis, which is rare, has been reported after COVID-19 vaccination, but its management is not standardized.

METHOD

Members of the European Network for Drug Allergy and the European Academy of Allergy and Clinical Immunology interested in drug allergy participated in an online questionnaire on pre-vaccination screening and management of allergic reactions to COVID-19 vaccines, and literature was analysed.

RESULTS

No death due to anaphylaxis to COVID-19 vaccines has been confirmed in scientific literature. Potential allergens, polyethylene glycol (PEG), polysorbate and tromethamine are excipients. The authors propose allergy evaluation of persons with the following histories: 1-anaphylaxis to injectable drug or vaccine containing PEG or derivatives; 2-anaphylaxis to oral/topical PEG containing products; 3-recurrent anaphylaxis of unknown cause; 4-suspected or confirmed allergy to any mRNA vaccine; and 5-confirmed allergy to PEG or derivatives. We recommend a prick-to-prick skin test with the left-over solution in the suspected vaccine vial to avoid waste. Prick test panel should include PEG 4000 or 3500, PEG 2000 and polysorbate 80. The value of in vitro test is arguable.

CONCLUSIONS

These recommendations will lead to a better knowledge of the management and mechanisms involved in anaphylaxis to COVID-19 vaccines and enable more people with history of allergy to be vaccinated.

Isocyanates may contribute to allergic contact dermatitis from diabetes devices and wound dressings

BACKGROUND

Isocyanates are well-known occupational allergens, but can also be present in medical devices.

OBJECTIVES

To highlight that contact sensitization to isocyanates might contribute to allergic contact dermatitis (ACD) from polyurethane (PU)-containing diabetes devices and wound dressings.

PATIENTS AND METHODS

Nineteen patients with suspected allergic contact dermatitis (ACD) from diabetes devices and/or wound dressings were patch tested to an isocyanate series. Four wound dressings, 6 diabetes devices and 4 monomeric isocyanate patch test preparations were analysed with gas chromatography - mass spectrometry (GC/MS).

RESULTS

Eight patients reacted to isocyanates and corresponding amines: 3 to isophorone diisocyanate (IPDI), 4 to 4,4'-diaminodiphenylmethane (MDA), 4 to 2,4-toluene diisocyanate (TDI) and 1 to polymeric methylene diphenyl diisocyanate (PMDI). Three of 4 wound dressings contained isocyanates (MDI, TDI and/or IPDI), whereas 5 of 6 diabetes devices contained 4,4'-methylene diphenyl diisocyanate (MDI), and one of them also IPDI. None of the medical devices contained 1,6-hexamethylene diisocyanate (HDI). Contrary to IPDI, and especially MDI, only the concentration of the TDI patch test preparation corresponded approximately (80%) to its label.

CONCLUSION

Patch tests with isocyanates may be worth-while in patients with suspected ACD from PU-containing medical devices. Besides MDA, and PMDI, also TDI might potentially be a marker for MDI-sensitization. This article is protected by copyright. All rights reserved.

Contact dermatitis: An important consideration in leg ulcers

The prevalence of chronic wounds is increasing with the aging population, with 1% to 2% of the worldwide population experiencing leg ulcers and positive patch tests reported in up to 75% of this population. With the introduction of modern dressings and compression therapies, clinicians should be cognizant of the potential risk of contact dermatitis in patients with leg ulcers. Contact dermatitis (both allergic and irritant) to wound products may present as maceration, pain, and overall impaired wound healing. Herein, we review the literature on contact dermatitis to wound-care products.

Allergic contact versus irritant contact dermatitis in patients with hard-to-heal leg ulcer: clinical and diagnostic approach

BACKGROUND

Dermatitis of surrounding skin may complicate hard-to-heal leg ulcers, delaying wound healing. The coexistence of hard-to-heal leg ulcers and irritant or allergic contact dermatitis may create difficulties for both diagnostic and therapeutic management.

OBJECTIVE

The aim of our study was to evaluate the incidence of dermatitis occurring in the surrounding skin in a population affected by hard-to-heal leg ulcers during treatment, and to differentiate between allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD) with the use of a patch test. Furthermore, we investigated which medications were most probably related to these conditions.

METHOD

We conducted an observational study from 21 February to 21 July 2017, enlisting all patients affected by hard-to-heal leg ulcers who attended the Wound Care Service of the Dermatologic Department of ASST, Spedali Civili, Brescia, Italy.

RESULTS

We enrolled 95 patients; 81 patients did not develop dermatitis, while 14 patients developed dermatitis of the surrounding skin. These patients underwent a patch test which gave a positive result in seven patients, permitting the diagnosis of ACD.

CONCLUSION

Our study confirmed the incidence of dermatitis of the surrounding skin reported in the literature but reassessed the incidence of ACD as opposed to ICD.

Contact allergy and allergic contact dermatitis from benzalkonium chloride in a tertiary dermatology center in Melbourne, Australia

BACKGROUND

Benzalkonium chloride (BAK) is a quaternary ammonium compound that is used widely as an antiseptic and preservative. It is a strong irritant and considered a weak sensitizer.

OBJECTIVE

To analyze the temporal trend of BAK sensitization and the demographics of sensitized patients.

METHODS

We conducted a single-center retrospective study of 7390 patients who were patch tested with BAK between January 1, 2003 and December 31, 2019.

RESULTS

Of the 7390 patients who were patch tested to BAK, 108 (1.5%) had a positive reaction, with 21 reactions deemed clinically relevant (0.3% of total patch tested) and a further 5 doubtful reactions deemed clinically relevant, resulting in a total of 26 relevant reactions (0.4% of total patch tested). Common sources of exposure were ophthalmic drops (30.8%), topical antiseptic preparations (26.9%), cosmetics (15.4%), disinfectant solutions (11.5%), hand sanitizers (11.5%), and hand washes (7.7%). One fifth of patients with relevant reactions were health care workers. There has been a dramatic increase in the number of positive reactions since 2017, for reasons not totally clear.

CONCLUSION

Contact allergy (CA) and allergic contact dermatitis (ACD) in response to BAK are now increasing at our center. Awareness of this trend is important, given that the coronavirus disease 2019 (COVID-19) pandemic is likely to further expose people to BAK.

A review of acrylates: Super glue, nail adhesives, and diabetic pump adhesives increasing sensitization risk in women and children

Allergic contact dermatitis (ACD) is a cutaneous type IV hypersensitivity immune reaction mounted against substances in contact with the skin to which the patient has been sensitized. ACD is common, affecting approximately 72 million Americans per year, and is more common in women. One common contact allergen group is acrylates, which are monomers that are polymerized in the making of glues, adhesives, and plastic materials. It is the monomers that are sensitizing, whereas the final polymers are inert. Acrylates were the 2012 Contact Allergen of the Year with the specific acrylate, isobornyl acrylate, being the 2020 Contact Allergen of the Year. This article reviews the history of acrylate use, epidemiology, and both known and emerging sources of acrylates resulting in ACD.

Surrounding skin management in venous leg ulcers: A systematic review

OBJECTIVES

Chronic venous insufficiency may lead to the development of venous leg ulcers, the most common form of chronic wounds in the lower extremity. Key to venous leg ulcer care is the maintenance of healthy skin surrounding the ulcer, as failure to maintain skin integrity may influence the healing outcome. We thus reviewed the scientific literature looking for assessment and management instruments regarding this common but often neglected issue.

METHOD

The search included all studies published between 2000 and May 2019. Keywords used were: "peri-wound skin care", "surrounding skin venous ulcers", "surrounding skin management leg ulcers", and "peri-lesional skin management".

RESULTS

Management of moisture-balance with the selection of appropriate dressings is the most important target in surrounding-wound skin care. Moreover, contact dermatitis related to products and the dressings themselves is a neglected problem in patients with chronic leg ulcers which clinicians increasingly have to manage. The literature search revealed that there is an increasing interest in the use of noninvasive assessment tools in the field of wound care, and focusing on the surrounding-wound skin plays a role in assessing the potential of wound healing. Transepidermal water loss measurement (TEWL) and ultrasonography are two of the measurement techniques available.

CONCLUSION

The integrity of the surrounding skin is necessary for wound healing, and appropriate management is needed to address this aspect which is part of an overall approach to treating wounds.

Allergic contact dermatitis caused by acrylic-based medical dressings and adhesives

BACKGROUND

Acrylates and methacrylates are acrylic resin monomers that are known to induce skin sensitization as a result of their presence in different materials, such as nail cosmetics, dental materials, printing inks, and adhesives. Allergic contact dermatitis resulting from the use of modern wound dressings containing them has only rarely been reported.

OBJECTIVES

To describe 2 patients who developed allergic contact dermatitis caused by acrylic-based modern medical dressings and/or adhesives.

METHODS

The medical charts of patients consulting since 1990 were retrospectively reviewed for (meth)acrylate allergy resulting from contact with such materials, and their demographic characteristics and patch test results were analysed.

RESULTS

Two patients were observed in 2014 and 2016 who had presented with positive patch test reactions to several acrylic-based dressings and/or adhesive materials, and to several (meth)acrylates, that is, hydroxyethyl acrylate, hydroxyethyl methacrylate, ethyleneglycol dimethacrylate, bisphenol A-glycidyl methacrylate/epoxy-acrylate, urethane diacrylate, and/or penta-erythritol acrylate.

CONCLUSIONS

Allergic contact dermatitis needs to be considered in patients with eczematous reactions or delayed healing following the use of acrylic-based modern dressings or adhesives. However, identification of the culprit allergen is hampered by poor cooperation from the producers, so adequate labelling of medical devices is an urgent necessity.

[Frequency of contact sensitization to modern dressings used to treat chronic leg ulcer]

INTRODUCTION

Allergic contact dermatitis around chronic leg ulcers (CLU) is a common complication in patients presenting CLU and prolongs healing times. The aim of this study was to describe the rate of sensitization to modern dressings (MD) used in these patients and to assess whether there is a relation between the number of sensitizations and ulcer type, the time from onset of the ulcer, and patient age and gender.

PATIENTS AND METHODS

We conducted a retrospective study at Reims University Hospital between 2010 and 2014 that included all patients with CLU of vascular etiology surrounded by eczematous lesions, and who had one of the patch-tests in the following 3 series: European baseline±leg ulcers±corticosteroids.

RESULTS

Among the 73 patients included, 43 % were polysensitized. Thirty-three patients (45 %) were sensitized to MD (38 % to hydrocolloids, 18 % to hydrogels, 7 % to hydrocellular dressings, 7 % to hydrofiber dressings, 5 % to contact layers and 3 % to alginates). Median age and sex did not differ between "polysensitized" patients and "non-polysensitized" patients (P=0.84 and P=0.25, respectively). Polysensitization was more frequent among patients presenting ulcers for more than 5 years (P=0.032).

CONCLUSION

Practically half of all patients presenting CLU with surrounding contact dermatitis had sensitization to modern dressings (mostly hydrocolloids and hydrogels). The rate of sensitization increased with the length of presence of CLU.

On the significance of negative-pressure wound therapy with instillation in dermatology

Methods used in the treatment of acute and chronic wounds undergo constant evolution, reevaluation, and innovation. While negative-pressure wound therapy (NPWT) is an established treatment modality, the combination of NPWT and instillation of normal saline as well as solutions with active antiseptic components for topical treatment of the wound bed represents a novel approach. The well-known effects of NPWT may thus be combined with those of local antisepsis. They include a decrease in wound area, induction of granulation tissue, and reduction in bacterial colonization. To date, studies have focused on NPWT with instillation for orthopedic/surgical indications, whereas clinical data in dermatosurgery is limited to case reports or small case series. There are as yet no randomized prospective studies investigating NPWT with instillation in the treatment of skin disorders. The goal of this review is to present the method of NPWT with instillation, to highlight its mode of action as well as possible complications and contraindications, and to review the recent literature. In summary, there is increasing evidence that both simple and complicated wounds may be effectively treated with NPWT with instillation, resulting in markedly accelerated tissue granulation and thus earlier defect closure.

An unusual presentation of a common condition: Allergic contact dermatitis

Allergic contact dermatitis commonly affects patients with chronic venous leg ulcers and can contribute to impaired wound healing. Many allergens have been identified, and despite the use of advanced dressings, the incidence of allergy has remained high. We discuss an unusual presentation of allergic contact dermatitis in a patient with a chronic wound. The patient's history was consistent with a recurrent venous leg ulcer, but on this occasion, the wound continued to deteriorate despite optimal treatment. This prompted further investigation, which included patch testing. Although the clinical features were not suggestive of allergy, the patch test was positive for several allergens, including Atrauman^® dressings, which the patient was using at the time. This case highlights the importance of regular reassessment and accurate diagnosis for the management of chronic wounds. It also demonstrates that allergic contact dermatitis can contribute to delayed wound healing without causing the classical clinical features of inflammation of the surrounding skin, and even hypoallergenic, non-adherent dressings can be sensitising.

Contact sensitivity in patients with venous leg ulcer: A multi-centric Indian study

Venous leg ulcers are the most common form of non-healing leg ulcers. They are subjected to treatments such as topical medications, dressings, and compression therapies. This can lead to exposure to a number of allergens with subsequent sensitisation and contact dermatitis of the regional skin. This may contribute to the poor ulcer healing. To detect the various contact sensitisers in patients with venous leg ulcers through patch testing, patients from 6 centres across India with venous leg ulcers of longer than 6 weeks duration were enrolled for the study. They were patch tested using a special parch test kit with 27 antigens. A total of 172 patients were included in the study; 82 (48.2%) tested positive for at least 1 antigen. Among them, polyvalent sensitisation was noted in 71% of patients. Wood tar mix (10.4%) and the framycetin (8.7%) were the most common allergens. There is a high frequency of allergic sensitisation to various ingredients of topical therapies used in the venous ulcer management, which may interfere with wound healing. Avoiding them can help obtain a better therapeutic outcome.

Wound-Related Allergic/Irritant Contact Dermatitis

PURPOSE

To provide information from a literature review about the prevention, recognition, and treatment for contact dermatitis.

TARGET AUDIENCE

This continuing education activity is intended for physicians and nurses with an interest in skin and wound care.

OBJECTIVES

After participating in this educational activity, the participant should be better able to:1. Identify signs and symptoms of and diagnostic measures for contact dermatitis.2. Identify causes and risks for contact dermatitis.3. Select appropriate treatment for contact dermatitis and its prevention.

ABSTRACT

Contact dermatitis to wound care products is a common, often neglected problem. A review was conducted to identify articles relevant to contact dermatitis.A PubMed English-language literature review was conducted for appropriate articles published between January 2000 and December 2015.Contact dermatitis is both irritant (80% of cases) or allergic (20% of cases). Frequent use of potential contact allergens and impaired barrier function of the skin can lead to rising sensitization in patients with chronic wounds. Common known allergens to avoid in wound care patients include fragrances, colophony, lanolin, and topical antibiotics.Clinicians should be cognizant of the allergens in wound care products and the potential for sensitization. All medical devices, including wound dressings, adhesives, and bandages, should be labeled with their complete ingredients, and manufacturers should be encouraged to remove common allergens from wound care products, including topical creams, ointments, and dressings.

The tissue residues of sodium dehydroacetate used as feed preservative in swine

BACKGROUND

Sodium dehydroacetate (Na-DHA) is a food and feed additive with antimicrobial effects. There is little information on Na-DHA residue levels in foods derived from animals. In this study, Na-DHA residue levels in swine tissues were determined by HLPC, and the pharmacokinetics of Na-DHA in tissues were determined.

RESULTS

The Na-DHA residue levels in swine tissues were <1.2 mg kg^-1 at different withdrawal time after thirty-two Duroc × Landrace × Yorkshire pigs were administered 200 mg Na-DHA kg^-1 through the feed for 30 days. In decreasing order of Na-DHA residue levels, the tissues were kidney > liver > muscle > fat. The pharmacokinetics of Na-DHA followed a binomial regression model, and the half-time of Na-DHA in swine tissues was 9.07 days for kidney, 7.19 days for liver, 6.66 days for muscle, and 5.39 days for fat tissue. The accuracy of the HPLC method for Na-DHA determination ranged from 80.18% to 91.33% recovery, with coefficients of variation <6.4%, limit of detection of 0.08 mg kg^-1 , and limit of quantification of 0.2 mg kg^-1 .

CONCLUSION

Na-DHA included at 200 mg kg^-1 in a swine diet is a safe feed additive based on residue elimination and ADI values reported. © 2017 Society of Chemical Industry.

The current spectrum of contact sensitization in patients with chronic leg ulcers or stasis dermatitis - new data from the Information Network of Departments of Dermatology (IVDK)

BACKGROUND

Patients with lower leg dermatitis, chronic venous insufficiency or chronic leg ulcers have a high prevalence of contact sensitization.

OBJECTIVES

To identify the current spectrum of contact allergens in these patients.

PATIENTS AND METHODS

Data of the Information Network of Departments of Dermatology on 5264 patients with the above diagnoses from the years 2003 to 2014 (study group) were compared with data on 4881 corresponding patients from 1994 to 2003 (historical control group) and with a current control group without these diagnoses (n = 55 510).

RESULTS

Allergic contact dermatitis was diagnosed less frequently in the study group than in the historical control group (25.9% versus 16.9%; p < 0.001), and contact sensitization to most allergens had declined. The allergen spectrum, however, was largely unchanged. Important allergens are Myroxylon pereirae (balsam of Peru) (14.8% positive reactions), fragrance mix I (11.4%), lanolin alcohol (7.8%), colophonium (6.6%), neomycin sulfate (5.0%), cetearyl alcohol (4.4%), oil of turpentine (3.1%), and paraben mix (2.6%). Patch testing with additional series showed sensitization to Amerchol L-101 (9.7%), tert-butyl hydroquinone (8.7%), framycetin sulfate (5.0%), and gentamicin sulfate (3.1%).

CONCLUSIONS

Topical preparations for treating the above-mentioned conditions should not contain fragrances, Myroxylon pereirae, and colophonium. The special allergen spectrum has to be considered in patch testing.

[When to worry about before a vascular chronic leg ulcer?]

Leg ulcers are a chronic condition. Healing can be long for venous ulcers and the risk of complications is significant. Infection is the most severe complication and can occur in the form of easily diagnosed acute bacterial dermohypodermitis that generally responds well to antibiotic treatment if given at an appropriate dose or in the form of localized infection that is more difficult to diagnosis. Indeed, no consensus has been reached in the literature on the clinical criteria to retain for the diagnosis of localized infection. Similarly, the most appropriate treatment remains to be established. Local care would be a logical starting point, followed by systemic antibiotics if this approach is unsuccessful. Individual conditions also should be taken into consideration (immunodepression, severe arteriopathy warranting more rapid use of systemic antibiotics). The second most frequent complication is an allergic reaction to a topical agent used for wound care. The rate of sensitivization in patients with leg ulcers is high (60 %), although the rate is declining with modern dressings. No product can be considered perfectly safe for these polysensitized patients. Dermocorticoid therapy can be very effective. Allergology tests are needed. Certain leg ulcers require special care from diagnosis. An arterial origin must be suspected for deep, or necrotic ulcers. Arterial supply must be explored rapidly, followed by a revascularization procedure when necessary. Highly painful superficial extensive necrotic ulcers due to necrotic angiodermitis require hospital care for skin grafts that will control the antiodermitis and provide pain. Carcinoma should be suspected in cases of leg ulcers with an atypical localization exhibiting excessive budding. A biopsy is mandatory for leg ulcers with an unusual course (absence of healing despite well-conducted care).

Zum Stellenwert der Unterdruck-Instillationstherapie in der Dermatologie

Die Methoden zur Behandlung akuter und chronischer Wunden unterliegen einer steten Weiterentwicklung, Reevaluierung und Anwendung innovativer Therapieformen. Die Vakuumtherapie zur Wundbehandlung gehört zu den etablierten Behandlungsmodalitäten. Ein innovatives Verfahren kombiniert die Vakuumtherapie mit der automatisierten, kontrollierten Zufuhr und Drainage wirkstoffhaltiger Lösungen zur topischen Wundbehandlung im Wundbett und auch wirkstofffrei durch Instillation physiologischer Kochsalzlösung (Unterdruck-Instillationstherapie). Hierdurch können die Effekte der konventionellen Vakuumtherapie mit denen der lokalen Antisepsis kombiniert werden. Hierdurch kommt es zu einer Reduktion der Wundfläche, einer Induktion von Granulationsgewebe sowie einer Reduktion der Keimbesiedelung der Wunden. Bisher publizierte Studien konzentrieren sich auf die Anwendung dieses Therapieverfahrens zur Behandlung orthopädisch-chirurgischer Krankheiten. Die Datenlage bezüglich der Vakuum-Instillationstherapie in der Dermatochirurgie beschränkt sich derzeit auf Fallberichte und Einzelfallerfahrungen. Randomisierte, prospektive Studien zum Vergleich der Vakuum-Instillationstherapie zur Behandlung dermatologischer Krankheitsbilder existieren bislang nicht. Ziele des vorliegenden Artikels sind die Vorstellung der Vakuumtherapie mit Instillation einschließlich ihres Wirkprinzips, deren mögliche Komplikationen, die Diskussion erdenklicher Kontraindikationen sowie eine Übersicht über die aktuell verfügbare Datenlage. Zusammenfassend scheint sich die Evidenz zu verdichten, dass mittels Unterdruck-Instillationstherapie sowohl einfache als auch komplizierte Wunden effizient behandelt werden können, was sich in einer deutlichen Beschleunigung der Wundgranulation mit konsekutiv früher möglichem Defektverschluss äußert.

Wound dressings, does it matter and why?

Compression therapy and treating venous insufficiency is the standard of care for venous leg ulcers. The need for debridement on healing venous leg ulcers is still debated. Dressings are often used under compression bandages to promote faster healing and prevent adherence of the bandage to the ulcer. A wide range of dressings is available, including modern dressings with different kinds of biological activity. Microbial burden is believed to underlie delayed healing, but the exact role of microbiofilm in wound healing is uncertain. Before choosing a specific wound dressing, four main functions should be considered: (1) cleaning, (2) absorbing, (3) regulating or (4) the necessity of adding medication. There is no clear evidence to support the use of one dressing over another, as demonstrated by many Cochrane review studies. In addition, the prescriber should enquire about contact allergies that may also develop during wound treatment. It is shown that early intervention and early investment may reduce the cost of treatment. The choice of wound dressings should be guided by cost, ease of application and patient and physician preference and be part of the complete strategy. The role of the medical specialist is evident. Wound dressings matter as part of the optimal treatment in VLU patients.