Itch and Pain Behaviors in Irritant Contact Dermatitis Produced by Sodium Lauryl Sulfate in Mice.

Irritant contact dermatitis (ICD) is a nonspecific skin inflammation caused by irritants, leading to itch and pain. We tested whether differential responses to histamine-dependent and -independent pruritogens can be evoked in ICD induced by sodium lauryl sulfate (SLS). An ICD mouse model was established with 5% SLS in acetone versus a vehicle topically applied for 24 h to the cheek. Site-directed itch- and pain-like behaviors, occurring spontaneously and in response to mechanical, thermal, and chemical stimuli (histamine, ß-alanine, BAM8-22, and bradykinin) applied to the cheek, were recorded before (day 0) and after irritant removal (days 1, 2, 3, and 4). Skin inflammation was assessed through visual scoring, ultrasound, and measurements of skin thickness. SLS-treated mice exhibited hyperalgesia-like behavior in response to mechanical and heat stimuli on day 1 compared to the controls. SLS mice exhibited more spontaneous wipes (pain) but not scratching bouts (itch) on day 1. Pruritogen injections caused more scratching but not wiping in SLS-treated mice compared to the controls. Only bradykinin increased wiping behavior compared to saline. SLS-treated mice developed noticeable erythema, scaling, and increased skin thickness on days 1 and 2. SLS induced cutaneous inflammation and behavioral signs of spontaneous pain and itching, hyperalgesia to mechanical and heat stimuli and a chemical algogen, and enhanced itch response to pruritogens. These sensory reactions preceded the inflammation peak and lasted up to two days.

Moisture-associated skin damage: an overview of its diagnosis and management.

This educational article introduces an explores moisture-associated skin damage (MASD) and the four forms it manifests as, namely, incontinence-associated dermatitis; intertriginous dermatitis; peristomal moisture-associated dermatitis; and peri-wound moisture-associated dermatitis. The aetiology and predisposing factors of each form are critically discussed, in addition to the treatments and interventions that can be used by nurses to support patient recovery. Nurses and other health professionals working with patients who are at risk of skin damage or who already require wound care, must be knowledgeable about all aspects of MASD. Fortunately, a plethora of evidence-based literature exists to support health professionals in their practice, although validated assessment and recording tools for incontinence-associated dermatitis are limited.

How to manage incontinence-associated dermatitis in older adults.

An estimated 14 million adults experience incontinence in England alone, and this population is at a very high risk of developing incontinence-associated dermatitis (IAD). The risk associated with developing IAD is further increased among older adults, due to the effects of the ageing process, which leave the skin thinner and more fragile. Understanding the causative factors of IAD in addition to understanding the impact of IAD on the skin enable the clinician to make informed choices regarding treatment, management and prevention. Additionally, understanding the association between IAD and pressure ulcers is a critical component of IAD management, as IAD and pressure ulcers often coexist or develop alongside each other.

The role of skin barrier in occupational contact dermatitis.

Skin diseases represent one of the most common work-related diseases and may have a detrimental effect on social, personal and occupational aspects of life. Contact dermatitis (CD), which comprises predominately irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD), accounts for vast majority of occupational skin diseases, especially in occupations associated with frequent skin contact with irritants and contact allergens. Although ICD and ACD have similar clinical manifestation, their pathophysiology and the role of the skin barrier are different. In ICD, perturbation of the skin barrier is the primary event which sets into motion diverse metabolic processes and triggers activation of innate immunity without the involvement of adaptive immune system. In ACD, a type IV hypersensitivity reaction induced by contact allergens, the skin barrier impairment may evoke innate signalling pathways during the sensitization phase required for the activation of T-cell adaptive response. Thus, skin barrier impairment may increase the risk of ICD or ACD not only because of enhanced permeability and ingress of irritants and allergens but also by the generation of innate immune signal needed for the induction of allergic response. Hence, an efficient way to prevent CD is to avoid skin barrier damage in the workplace. This review focuses on the skin barrier, how it is affected by skin irritants and how its impairment contributes to the development of ICD and ACD.

Specific barrier response profiles after experimentally induced skin irritation in vivo.

BACKGROUND: Recently, natural moisturizing factors (NMFs) and corneocyte surface topography were suggested as biomarkers for irritant dermatitis. OBJECTIVES: To investigate how exposure to different irritants influences corneocyte surface topography, NMF levels and the barrier function of human skin in vivo. METHODS: Eight healthy adult volunteers were exposed to aqueous solutions of 60% n-propanol, 0.5% sodium lauryl sulfate (SLS), 0.15% sodium hydroxide, and 2.0% acetic acid, and distilled water, in a repeated irritation test over a period of 96 hours. Erythema, transepidermal water loss (TEWL), skin hydration, the dermal texture index (DTI) and NMF levels were measured at baseline, and after 24 and 96 hours. RESULTS: SLS and sodium hydroxide had the most pronounced effects on erythema and TEWL. Although n-propanol caused only slight changes in TEWL and erythema, it showed pronounced effects on skin hydration, NMF levels, and the DTI. NMF was the only parameter that was significantly altered by all investigated irritants. The changes in the DTI were inversely associated with NMF levels and skin hydration. CONCLUSION: Skin barrier impairment and the inflammatory response are irritant-specific, emphasizing the need for a multiparametric approach to the study of skin irritation. NMF levels seem to be the most sensitive parameter in detecting irritant-induced skin barrier alterations.

IRRITANT AND ALLERGIC CONTACT DERMATITIS - SKIN LESION CHARACTERISTICS.

- Contact skin lesions may be the consequences of contact with various irritants or allergens, or due to other factors (e.g., UV radiation, microbials), intrinsic factors (e.g., in autoimmune responses), or even their combination. There are many substances related to irritant contact dermatitis (CD), causing irritant or toxic effects, e.g., chemical and physical agents, plants, phototoxic agents, airborne irritants, etc. Impaired barrier function (e.g., aberrancies in epidermal pH buffering capabilities) also participates by promoting bacterial biofilms and creating an environment favoring sensitization. Development of allergic CD skin lesions includes complex immune pathways and inflammatory mediators, influenced by both genetic (predominantly filaggrin mutations) and environmental triggers. In the pathogenesis of allergic CD, antimicrobial peptides play a prominent role; they are produced by various skin cells (e.g., keratinocytes, sebocytes) and move to inflamed lesions during an inflammation process. Also, in allergic CD skin lesions, the skin shows different types of immune responses to individual allergens, although clinical manifestations do not depend on the causative allergen type, e.g., nickel stimulates immune activation primarily of the Th1/Th17 and Th22 components. Also important are alarmins, proteases, immunoproteomes, lipids, natural moisturizing factors, tight junctions, smoking, etc. We expect that future perspectives may reveal new pathogenetic factors and scientific data important for the workup and treatment of patients with CD.

Management of Moisture-Associated Skin Damage: A Scoping Review.

BACKGROUND: Protecting the skin against moisture-associated damage is an important component of comprehensive skin and wound care. Based on a review of literature, the authors propose key interventions to protect and prevent damage in the skin folds, perineum, and areas surrounding a wound or stoma. OBJECTIVE: The aim of this scoping review is to identify and provide a narrative integration of the existing evidence related to the management and prevention of moisture-associated skin damage (MASD). METHODS: Study authors searched several databases for a broad spectrum of published and unpublished studies in English, published between 2000 and July 2015. Selected study information was collated in several different formats; ultimately, key findings were aggregated into a thematic description of the evidence to help generate a set of summative statements or recommendations. RESULTS: Based on inclusion criteria, 37 articles were considered appropriate for this review. Findings included functional definitions and prevalence rates of the 4 types of MASD, assessment scales for each, and 7 evidence-based strategies for the management of MASD. CONCLUSIONS: Based on this scoping review of literature, the authors propose key interventions to protect and prevent MASD including the use of barrier ointments, liquid polymers, and cyanoacrylates to create a protective layer that simultaneously maintains hydration levels while blocking external moisture and irritants.

Understanding Moisture-Associated Skin Damage, Medical Adhesive-Related Skin Injuries, and Skin Tears.

GENERAL PURPOSE: To provide information on superficial skin issues related to moisture-associated skin damage, medical adhesive-related skin injury, and skin tears. TARGET AUDIENCE: This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care. LEARNING OBJECTIVES/OUTCOMES: After participating in this educational activity, the participant should be better able to:1. Examine the anatomy of skin, including changes that occur from aging and chronic wounds.2. Identify issues related to moisture-associated skin damage, medical adhesive-related skin injury, and skin tears, including techniques for prevention. ABSTRACT: The purpose of this continuing education article is to examine the superficial skin issues related to moisture-associated damage, medical adhesive-related skin injury, and skin tears. Similarities, differences, prevention, and treatment will be described.

The Application of a Moldable Skin Barrier in the Self-Care of Elderly Ostomy Patients.

The quality of ostomy directly affects the stoma patient's quality of life. This study investigated the application of a moldable skin barrier in the self-care of elderly stoma patients after colostomy for colorectal cancer. A total of 104 elderly stoma patients (65-79 years) who underwent colostomy because of colorectal cancer were randomly divided into an experimental group (56 cases) receiving a moldable skin barrier and a control group (48 cases) receiving a conventional skin barrier. The information on peristomal irritant dermatitis occurrence, the satisfaction of self-care, and related care costs were collected 1 month after patients were discharged from the hospital. The overall incidence of irritant dermatitis was significantly lower (p = .01), the self-care satisfaction score was significantly higher (p = .02), and the cost for leakage-proof cream (p < .001) was significantly lower in the experimental group than in the control group. In contrast, no significant differences in the cost of ostomy equipment and the barrier replacement interval were observed. In conclusion, a moldable skin barrier can reduce the incidence of irritant dermatitis in elderly stoma patients, improve their self-care satisfaction, and reduce the cost of leakage-proof cream use compared with the conventional stoma skin barrier.

Effect of glove occlusion on the skin barrier.

Wet work tasks are the most common exposures leading to occupational irritant contact dermatitis. Use of liquid-proof gloves is recommended when performing wet work, however, gloves may also contribute to impairment of the skin barrier and development of irritant contact dermatitis. The aim of this study is to review the literature on the effects of glove occlusion on skin barrier function. The PubMed database was searched up to 1 February 2015 for articles on the association between glove occlusion and skin barrier function, including human studies only and in English. Only experimental studies including assessment of the skin barrier function were included in the data analysis. Thirteen articles were identified, 8 with focus on occlusion alone, 7 with focus on occlusion in combination with irritant exposure (some overlapping), and 2 field studies. In conclusion, data from the literature showed that the negative effect of occlusion in itself is limited, and that only extensive and long-term occlusion will cause barrier impairment. However, studies investigating combined effect of occlusion and exposure to soaps/detergents indicate that occlusion significantly enhances the skin barrier damage caused by detergents/soaps in a dose-response fashion.

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.

Thymic stromal lymphopoietin induction by skin irritation is independent of tumour necrosis factor-α, but supported by interleukin-1.

BACKGROUND: Thymic stromal lymphopoietin (TSLP) is an extensively studied cytokine linked to the pathogenesis of allergic diseases, but the inherent activities behind TSLP expression are not well defined. OBJECTIVES: To explore the conditions favourable to TSLP induction outside of a typically allergic set-up and determine the associated mechanisms, and to assess whether TSLP is similarly controlled in murine and human skin. METHODS: A combination of primary keratinocytes, skin explants/epidermal sheets and in vivo strategies was employed. The skin of wild-type and tumour necrosis factor knockout (TNF-/-) mice was subjected to acute irritation. Cells and specimens were stimulated with a range of TSLP inducers in the presence or absence of neutralizing antibodies. TSLP was quantitated by quantitative reverse-transcriptase polymerase chain reaction, enzyme-linked immunosorbent assay and immunohistochemistry. RESULTS: In addition to cytokines, skin irritation brought about by various causes (e.g. shaving, scratching and chemical perturbation) elicited uniformly high-level production of TSLP, which entered the circulatory system. Despite the potency of TNF-α as an in vitro TSLP inducer, the use of TNF-/- mice revealed that this mechanism was completely independent of endogenous TNF-α. Conversely, irritation-elicited TSLP depended on interleukin (IL)-1, which had a more pronounced influence in human skin than in murine skin. Murine and human skin differed considerably regarding TSLP regulation. CONCLUSIONS: Thymic stromal lymphopoietin is a general responder to disrupted skin homeostasis and may have a role in triggering the alarm system of the skin. TSLP induction is rapid, transient and driven by a mechanism that does not involve TNF-α, but partially relies on the evolutionarily ancient IL-1 system. The irritated skin secretes TSLP into the circulatory system. TSLP regulation varies between species.

Skin reaction and regeneration after single sodium lauryl sulfate exposure stratified by filaggrin genotype and atopic dermatitis phenotype.

BACKGROUND: Filaggrin is key for the integrity of the stratum corneum. Mutations in the filaggrin gene (FLGnull) play a prominent role in atopic dermatitis (AD) pathogenesis. People with AD have increased susceptibility to irritants. However, little is known about the effect of filaggrin genotype and AD phenotype on irritant response and skin regeneration. OBJECTIVES: To investigate the role of FLGnull and AD groups for skin reaction and recovery after sodium lauryl sulfate (SLS) irritation. METHODS: This is a case-control study comprising 67 subjects, including healthy controls and patients with and without FLGnull and AD. Reactivity to different doses of SLS at 24, 48, 72 and 145 h after SLS application was measured by transepidermal water loss (TEWL) and laser Doppler flowmetry (LDF). Reactivity was assessed univariately and by pattern analysis. RESULTS: All patient groups showed a higher degree of skin-barrier disruption and inflammation than did controls in response to SLS. Assessing reactivity by the delta value of the area under the curve for both TEWL and LDF showed significant differences between healthy controls and those with the AD phenotype, irrespective of filaggrin mutation. The poorest regeneration was among those with the AD phenotype. The two AD phenotype groups were separated by multivariate technique, due to earlier inflammatory reactivity among subjects with FLGnullplus AD compared with the AD phenotype alone. CONCLUSIONS: Both skin reaction and regeneration were significantly different between the patient population and the healthy controls. Additionally, response severity and regeneration depended more on AD phenotype than on filaggrin genotype, whereas the response was more rapid among the FLGnullplus AD individuals.

Direct comparison of laser Doppler flowmetry and laser Doppler imaging for assessment of experimentally-induced inflammation in human skin.

OBJECTIVE AND DESIGN: Laser Doppler imaging (LDI) and laser Doppler flowmetry (LDF) can measure localized skin perfusion. The purpose of the study was to directly compare LDF with LDI as a tool for measuring skin blood changes in an experimental model of chemically-induced skin inflammation. METHODS: Regions of interest 1.8 cm² in area on the forearm skin of eight healthy volunteers were randomized and exposed to 0.25, 0.5, 1, or 2 % topical sodium lauryl sulfate (SLS) or vehicle for 24 h. Mean blood flow was measured by LDI and LDF at 24, 48, and 72 h. Inflammation was clinically graded using a standardized, clinical score. RESULTS: Sodium lauryl sulfate induced significant, dose-dependent local inflammation. Both Doppler methods were significantly correlated with the clinical grading (LDF, r = 0.755; LDI, r = 0.836). LDF and LDI showed similar significance differences with regard to dose- and time-response patterns compared to the vehicle. The absolute and relative LDF and LDI values were significantly correlated. CONCLUSIONS: Laser Doppler flowmetry and LDI showed similar dose- and time-response relations in irritant-induced inflammatory skin reactions. For the assessment of localized skin reactions, LDI possesses no apparent advantages over the less expensive LDF method for grading dermal inflammatory reactions.

Irritant contact dermatitis due to ammonium bifluoride in two infant twins.

Ammonium bifluoride is one of the most corrosive acids that may produce severe chemical burns when in contact with skin. This hazardous chemical is widely used in household products. We report two pediatric cases of irritant contact dermatitis after exposure to a rust remover, which contained ammonium bifluoride.

[The changes of skin barrier of patients with different facial dermatitis and the comparison of CE and KLK5].

OBJECTIVE: To study the clinical symptoms and the condition of skin barrier of different facial dermatitis. METHODS: The patients with facial dermatitis were divided into 4 groups based on their diagnosis: hormone-dependent dermatitis (HDD) group, sensitive skin (SS) group, cosmetic intolerance (CI) group and normal control group. All patients received the evaluation on clinical symptoms with measuring scale, measurements of stratum corneum water content (SCWC), sebum, pH, trans-epidermal water loss (TEWL) and blood flow. The skin scales were collected for the measurements of the ratio of immature cornified envelope (CE) via immunofluorescence and the concentration of kallikrein 5 (KLK5) via enzyme-linked immunosorbent assay. RESULTS: There were total 146 patients included (HDD 38, SS 53, CI 15, control group 30), most of them had their symptoms evaluated as moderate to severe. Compared with the control, the disease groups had lower SCWC and sebum (P < 0.05), higher pH, TEWL and blood flow (P < 0.05), higher ratio of immature CE (P = 0.011) and lower concentration of KLK5 (P = 0.000); while these parameters among the disease groups did not show statistical significant difference. CONCLUSION: There is no difference in the clinical symptoms and the condition of skin barrier between facial dermatitis with different inducements. The growth of CE may be inhibited and the concentration of KLK5 decreases in facial dermatitis.

Percutaneous absorption in diseased skin: an overview.

The stratum corneum's (SC) functions include protection from external hazardous environments, prevention of water loss and regulation of body temperature. While intact skin absorption studies are abundant, studies on compromised skin permeability are less common, although products are often used to treat affected skin. We reviewed literature on percutaneous absorption through abnormal skin models. Tape stripping is used to disrupt water barrier function. Studies demonstrated that physicochemical properties influence the stripping effect: water-soluble drugs are more affected. Abrasion did not affect absorption as much. Freezing is commonly used to preserve skin. It does not seem to modify water absorption, but still increases the penetration of compounds. Comparatively, heating the skin consistently increased percutaneous absorption. Removing SC lipids may increase percutaneous absorption of drugs. Many organic solvents are employed to delipidize. Delipidization with chloroform-methanol increased hydrophilic compound permeability, but not lipophilic. Acetone pre-treatment enhanced hydrophilic compound penetration. More data is needed to determine influence on highly lipophilic compound penetration. Sodium lauryl sulfate (SLS) induces irritant dermatitis and is frequently used as a model. Studies revealed that SLS increases hydrophilic compound absorption, but not lipophilic. However, skin irritation with other chemicals increases lipophilic penetration as much as hydrophilic. Animal studies show that UV exposure increases percutaneous absorption whereas human studies do not. Human studies show increased penetration in psoriatic and atopic dermatitis skin. The data summarized here begin to characterize flux alteration associated with damaged skin. Understanding the degree of alteration requires interpretation of involved conditions and the enlarging of our database to a more complete physicochemical spectrum.

Topical antioxidants protect the skin from chemical-induced irritation in the repetitive washing test: a placebo-controlled, double-blind study.

BACKGROUND: There is increasing evidence that reactive oxygen species play an important role in the development of both irritant and allergic contact dermatitis. OBJECTIVES: To assess the potential of topical antioxidants to prevent the development of experimentally induced irritant contact dermatitis. METHODS: We evaluated the effect of a cream containing a combination of antioxidants on sodium lauryl sulfate-induced irritant contact dermatitis in the repetitive washing test. As readout parameters for skin barrier function and cutaneous inflammation stratum corneum hydration, cutaneous blood flow and transepidermal water loss were assessed in 25 volunteers with bioengineering methods. RESULTS: In comparison with the cream base and a frequently used barrier cream, the antioxidant cream had high radical scavenging activity and effectively protected the skin from chemical-induced irritation. CONCLUSIONS: The superiority of the cream with antioxidants to the cream base suggests that reactive oxygen species, at least in part, play a role in the development of irritant contact dermatitis.

Evidence of increased skin irritation after wet work: impact of water exposure and occlusion.

BACKGROUND: Exposure to humid environments/water and prolonged glove occlusion are both believed to cause irritant contact dermatitis. OBJECTIVES: To study the effects of different forms of wet work, especially the differences between water exposure and occlusion, by using an experimental model simulating occupational wet work. METHODS: The responses to water exposure and occlusion over multiple daily exposure periods for 7 days were compared in 73 volunteers. After the 1 week exposure, the sites were irritated with sodium lauryl sulfate (SLS). Comparison was performed via visual inspection and bioengineering methods. RESULTS: Whereas occlusion did not induce measurable alterations in skin physiology, water exposure for more than 3 hr daily caused a significant increase in transepidermal water loss (TEWL) as compared with the control areas. SLS irritation of the previously occluded and the water-exposed sites induced higher TEWL and clinical scores in a time-dependent fashion as compared with the control areas, with more pronounced reactions in the water-exposed sites than in the occluded sites. CONCLUSION: Both previous occlusion and water exposure were capable of inducing higher susceptibility to SLS irritation. Skin hydration by occlusion had a different biological effect than water exposure. Short occlusions seem to harm the skin less than water exposure for the same duration.

Allergic contact dermatitis: immune system involvement and distinctive clinical cases.

The aim of this review is drawing the attention to the contact dermatitis, an inflammatory skin condition due to pro-inflammatory and toxic factors able to activate the skin innate immunity (irritant contact dermatitis) or caused by a T-cell- mediated hypersensitivity reaction (allergic contact dermatitis). The immune system involvement and a variety of clinical pictures are described in order to better diagnose, prevent and treat allergic contact dermatitis.