Occupational Contact Dermatitis

Reduced protein levels in latex gloves may play an alternative approach to lowering latex sensitization risks among health workers; a cross-sectional analytical study

BACKGROUND

Latex gloves are essential for protecting healthcare workers from biological hazards but pose a risk of latex allergy, particularly due to powdered, protein, and allergen content. Recent advancements in latex glove manufacturing have led to reduced levels of extractable proteins, a known factor triggering allergenic reaction. This study aimed to compare latex sensitization between nursing staff using low-protein and high-protein latex gloves at a tertiary university hospital in Thailand.

METHODS

A cross-sectional analytical study categorized participants into two groups based on glove exposure: the low extractable protein group (only exposed to non-powdered latex gloves with extractable protein levels below 50 µg/g) and the high extractable protein group (exposed to powdered latex gloves with levels above 50 µg/g). The sample size comprised 163 individuals in the low protein group and 318 in the high protein group (1:2). Latex allergy symptoms and sensitization were assessed using a self-administered questionnaire and latex-specific IgE measurement (ImmunoCAP), respectively. Data analysis involved descriptive and inferential statistics, including odds ratios and 95%CI.

RESULTS

Demographic data was mostly similar in both exposure groups except for age. No significant differences in latex sensitization between the low and high protein groups were found via latex-specific IgE measurement (crude OR 1.90, 95%CI: 0.5, 7.18), potentially attributed to lower extractable protein levels in powdered latex gloves compared to previous studies. In contrast, the low protein group exhibited significantly fewer current latex allergy symptoms in both bivariate (crude OR 0.24, 95%CI: 0.06, 0.74) and multiple variable analysis (adjusted OR 0.18, 95%CI: 0.04, 0.86). Moreover, there was a significant reduction in latex allergy symptoms among the low protein group, decreasing from 9.8% who reported experiencing symptoms (when powdered latex gloves were used) to 1.2% who still reported current symptoms (OR 0.11, 95%CI: 0.02, 0.44).

CONCLUSIONS

This study underscores the importance of using non-powdered and low-protein latex gloves to reduce latex allergy symptoms while emphasizing the need for further investigation into the relationship between extractable protein levels in addition to the attempt of the major allergen removal and latex sensitization amid evolving glove manufacturing practices.

Toll-Like Receptors and Contact Dermatitis

Contact dermatitis (CD) is a common cutaneous inflammatory condition that affects millions of people worldwide. Xenobiotic agents are frequently encountered in substances used in everyday life, making it difficult to avoid personal and occupational exposure. Toll-like receptors (TLRs) are transmembrane receptors that modulate the innate immune system in response to tissue injury or infection. TLRs play a key role in the pathophysiology of contact dermatitis. TLR signaling is involved in three major forms of CD: protein CD, allergic contact dermatitis (ACD), and irritant CD. Of the 10 TLRs found in humans, three play an important role in ACD. This makes TLRs a useful potential therapeutic target to consider against CD. In this review, we discuss the role of TLRs in CD and summarize current and emerging treatments for CD that target TLRs.

Dendritic cells under allergic condition enhance the activation of pruritogen-responsive neurons via inducing itch receptors in a co-culture study

BACKGROUND

Itch sensitization has been reported in patients with chronic allergic skin diseases and observed in a mouse model of allergic contact dermatitis (ACD). There is evidence suggesting that neuroimmune interactions may contribute to itch sensitization, as an increase in dendritic cells (DCs) within ganglia has been observed during allergic conditions. However, how DCs interact with sensory neurons in ganglia during allergic conditions is still not known. This study aims to investigate the role of DCs in dorsal root ganglion (DRG) under ACD conditions, specifically focusing on itch sensitization within the DRG. The tolylene-2,4-diisocyanate (TDI) mouse model for ACD and the co-culture model of DCs and DRG neurons was employed in this study.

RESULTS

We successfully induced ACD by TDI, as evidenced by the development of edema, elevated total serum IgE levels, and an observed itch reaction in TDI-sensitized mice. Calcium imaging and RT-qPCR analysis revealed that TDI-sensitized mice exhibited signs of peripheral sensitization, including a higher percentage of neurons responding to pruritogens and increased activation and expression of itch receptors in excised DRG of TDI-sensitized mice. Immunofluorescence and flow cytometric analysis displayed an increase of MHCII+ cells, which serves as a marker for DCs, within DRG during ACD. The co-culture study revealed that when DRG neurons were cultured with DCs, there was an increase in the number of neurons responsive to pruritogens and activation of itch receptors such as TRPA1, TRPV1, H1R, and TRPV4. In addition, the immunofluorescence and RT-qPCR study confirmed an upregulation of TRPV4.

CONCLUSIONS

Our findings indicate that there is an increase of MHCII+ cells and itch peripheral sensitization in DRG under TDI-induced ACD condition. It has been found that MHCII+ cells in DRG might contribute to the itch peripheral sensitization by activating itch receptors, as shown through co-culture studies between DRG neurons and DCs. Further studies are required to identify the specific mediator(s) responsible for peripheral sensitization induced by activated DCs.

A review of skin disease in military soldiers: challenges and potential solutions

Introduction: Military soldiers comprised 1,195 million United States active-duty members and 778,000 reserve members in 9/2021. Soldiers are often exposed to drastic climates, environments, and living conditions which may make them more susceptible to cutaneous diseases.Methods: A PubMed search of studies published between 1/1/2002 - 8/30/2022, using MeSH terms: ((("Military Personnel"[Majr]) OR "Military Hygiene"[Majr])) OR "Military Medicine"[Majr]) AND "Skin Diseases"[Majr]), the reference lists of select articles, and other applicable sources were reviewed to identify articles on skin conditions affecting military soldiers and treatment options.Discussion: In this article, we review skin conditions that affect military soldiers in both the deployed and non-deployed settings including infectious diseases, arthropod associated diseases, sexually transmitted infections, ultraviolet radiation related skin disease, acne, diseases of hair and hair follicles, dermatitis, onychocryptosis, and conditions caused by extreme weather conditions and occupational exposures. We also discuss treatment options and prevention methods as they relate to military settings.Conclusion: Dermatological conditions can considerably impact soldiers' wellbeing and military performance, often lead to evacuation of military personnel, and are associated with high financial costs. Cutaneous disease is one of most common reasons for soldiers to seek medical care and may cause significant morbidity. Serving in the military often impacts and limits treatment options.

Advancing the understanding of allergic contact dermatitis: from pathophysiology to novel therapeutic approaches

Allergic contact dermatitis (ACD) is a common inflammatory skin disease that, especially when the condition becomes chronic, has a high impact on the quality of life and represents a significant disease burden. ACD represents a type IV delayed-type hypersensitivity reaction that is triggered by contact with an allergen in previously sensitized individuals through the activation of allergen-specific T cells. In the acute phase, it is characterized by eczematous dermatitis, which presents with erythema, edema, vesicles, scaling, and intense itch. Non-eczematous clinical forms are also described (lichenoid, bullous, and lymphomatosis). Lichenification is the most common clinical picture in the chronic phase if the culprit allergen is not found or eliminated. ACD can be associated with both occupational and non-occupational exposure to allergens, representing approximately 90% of occupational skin disorders along with irritant contact dermatitis. Patch testing with suspected allergens is required for a diagnosis. Metals, especially nickel, fragrance mix, isothiazolinones, and para-phenylenediamine, are the most commonly positive allergens in patients patch tested for suspected ACD. The treatment goal is to avoid contact with the culprit agent and use topical and/or systemic corticosteroid therapy.

What Is New in Occupational Allergic Contact Dermatitis in the Year of the COVID Pandemic?

PURPOSE OF REVIEW

This article aims to summarize some recent trends in occupational allergic contact dermatitis (ACD), including dermatitis related to pandemic-level personal protective equipment in healthcare workers, hazards patients may experience when working from home, and occupational perspectives on the recent American Contact Dermatitis Society (ACDS) allergens of the year and ACDS Core Allergen Series updates.

RECENT FINDINGS

Recent ACDS Allergens of the Year may be particularly relevant to healthcare workers, including isobornyl acrylate, which is present in glucose sensors and propylene glycol present in hand cleansers and disinfectants. Lavender, limonene, and linalool, all of which are new additions to the ACDS Core Allergen Series, have been reported as causes for occupational ACD in massage therapists and aromatherapists. Isothiazolinone allergy continues to rise in both consumer and occupational settings. Finally, the COVID-19 pandemic has resulted in a wave of occupational ACD in healthcare workers to personal protective equipment, and revealed new potential allergens for individuals working from home. Occupational allergic contact dermatitis continues to exert a significant occupational disease burden. Remaining aware of the current trends in allergens may allow for earlier recognition, diagnosis, and treatment, subsequently helping our patients to work in healthier and safer environments.