Contact Allergy
Conditions
Brief summary
This study will investigate what concentrations of the most common thiurams and carbamates that elicit allergic contact dermatitis under patch test and what concentrations of the rubber accelerators that elicit allergic contact dermatitis by repeated exposures under simulated use conditions. Further, it will investigate whether a damaged skin barrier as caused by wet work increase the severity of the allergic contact dermatitis. The participants will be assigned to either the SLS (sodium lauryl sulfate)-group or non SLS-group. For the participants of the SLS-group, one volar forearm will be randomized to be pre-irritated with a soap i.e. detergent: sodium lauryl sulfate (SLS) for 24 hours to simulate wet work. The participants of the non SLS-group will not be pre-irritated with SLS. Following this, the participants' volar forearms will be exposed to thiurams or carbamates and a control solution every night for 7 nights to simulate the repeated exposure to rubber gloves with accelerators. The skin reactions will be read cf. current international guidelines and further quantified using laser Doppler flowmetry. During the study, all participants will be patch tested on the upper back with rubber accelerators to investigate their current degree of sensitization and the dose-response relationships.
Interventions
OTHERRubber accelerators and control chamber/solution for NON-SLS group
Repeated exposure to rubber accelerators and control chamber/solution on arms. Three different concentrations of rubber accelerators and one control chamber/solution will be applied on the arms.
OTHERSLS
Exposure to SLS on a randomized arm
OTHERRubber accelerators and control chamber/solution for SLS group
Repeated exposure to rubber accelerators and control chamber/solution on arms. Two different concentrations of rubber accelerators and one control chamber/solution will be applied on both arms.
OTHERPatch test on back
Patch test on the back with thiurams or carbamates in different concentrations and a control chamber/solution
Sponsors
National Allergy Research Center, Denmark
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
The forearm randomized to SLS and the order in which the different concentrations of thiurams and carbamates and the control solution are applied to the skin, will be blinded for the reader of the skin reactions and the latter also for the participant.
Intervention model description
The participants are assigned to either the SLS-group or NON-SLS-group.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
Allergic participants Inclusion Criteria: * Adults ≥18 years old * Sensitized to thiurams, carbamates or both. * Received written and oral information about the study. * Signed written consent form
Exclusion criteria
* Dermatitis on back or arms * Tattoos or significant scar tissue on exposure areas * Pregnancy * Breast feeding * Recently given birth * Treatment with systemic immunomodulators within the last 4 weeks * Treatment with local immunomodulators on arms or back within the last 4 weeks * Excessive ultraviolet light on arms or back within the last 4 weeks Healthy Controls: Inclusion Criteria: * adults ≥18 years old * Received written and oral information about the study. * Signed written consent form
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Reading of skin reactions | Day 0, Day 1 (only participants' arms in the SLS-group), Day 2 and Day 3 or Day 4, and Day 7, and Day 8. Further, eventually, if any reactions occur up to Day 16. | Development of dermatitis by reading of skin reactions based on international dermatitis scoring guidelines. |
| Skin blood flow | Day 0, Day 1 (only participants' arms in the SLS-group), Day 2 and Day 3 or Day 4, and Day 7, and Day 8. Further, eventually, if any reactions occur up to Day 16. | Changes in blood flow on the arms using laser doppler flowmetry |
Countries
Denmark
Outcome results
None listed