Although rare, photoallergic contact dermatitis caused by dust from various types of wood, mainly tropical species, is well documented. We report here a case of allergic contact dermatitis involving both airborne transmission and exposure to light.
1. Case Report
A 68‐year‐old man, with no history of atopic conditions and who worked with wood as a hobby, reported facial eczema that had been present for 1 year, affecting the entire face and neck, including the eyelids, the areas behind the ears and under the chin (Figure 1), which had progressed in flare‐ups and spread to his forearms. The patient was convinced that he was suffering from photosensitivity/photoallergy, as his symptoms worsened with sun exposure, despite the fact that he was not using any photosensitising medication. Various patch tests (IQ Ultra chambers, Chemotechnique) were performed using the European Baseline, Plant, Cosmetics and Photopatch series, but all proved negative. The patient had not brought any personal products. Given the involvement of sun‐exposed areas, phototests were then carried out. The minimal erythema dose (MED) for UVB was reduced to 0.07 J/cm2 and the MED for UVA was normal (> 9 J/cm2). Iterative phototests proved negative for both UVA and UVB.
FIGURE 1.
Eczema of the face and neck during allergist appointment.
Photo‐patch tests were positive (+) for non‐irradiated ebony dust (provided on this occasion by the patient) diluted to 10% in petrolatum (Figure 2a), positive (++) for ebony dust irradiated with UVB at 0.05 J/cm2 (DEM at 0.07 J/cm2) (Figure 2b) and positive (+++) for ebony dust irradiated with UVA at 8 J/cm2 (DEM > 9 J/cm2) (Figure 2c) on the fourth day. We concluded that the patient had a contact allergy to ebony with photoaggravation induced by UVA and UVB. Subsequently, he continued to work with wood using other local species, without any adverse effects.
FIGURE 2.
(a) Positive (+) patch testing for non‐irradiated ebony wood dust at Day 2; (b) Positive (++) patch testing for UVB‐irradiated ebony dust at Day 2; (c) Positive (++(+)) patch testing for UVA‐irradiated ebony dust at Day 2.
2. Discussion
Exotic woods are used for both professional and recreational purposes by carpenters and hobbyists to make a wide range of items, including decorative objects, furniture, tool handles, musical instruments and decorative jewellery such as bracelets and necklaces.
Exotic woods most commonly cause irritant contact dermatitis, but they can also induce allergic contact dermatitis, mainly linked to sensitising quinones [1, 2, 3, 4].
Photoallergy to wood is a rare phenomenon and, to our knowledge, only six cases have been described [5]. Due to the worsening and spread of the eczema to sun‐exposed areas, photopatch tests were performed and proved positive in all cases. It is noteworthy that, in our case, the photopatch tests were performed based on the patient's belief that he was photoallergic. Without this belief, we would have concluded that he had an airborne contact allergy to ebony dust. Overall, this suggests that photoallergy/photoaggravation to wood is likely underreported. Furthermore, quinones, which are the main sensitising agents present in wood, are highly photoreactive in the UV spectrum (6).
Clinicians should therefore be aware of the additional role that UV exposure may play in airborne contact dermatitis caused by wood. We also believe that a wood photopatch test should be routinely performed in such cases.
Author Contributions
Nicolas Rouyer: writing – original draft. Angéline Charansol: validation. Anatole Hanniet: validation. François Aubin: validation. Fabien Pelletier: validation. Florence Castelain: conceptualisation, investigation, writing – review and editing, supervision.
Consent
The patient gave written consent to publish their case details and photographs.
Conflicts of Interest
The authors declare no conflicts of interest.
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
References
- 1. Rackett S. C. and Zug K. A., “Contact Dermatitis to Multiple Exotic Woods,” American Journal of Contact Dermatitis 8, no. 2 (1997): 114–117. [PubMed] [Google Scholar]
- 2. Podjasek J. O., Cook‐Norris R. H., Richardson D. M., Drage L. A., and Davis M. D., “Allergic Contact Dermatitis From Exotic Woods: Importance of Patch‐Testing With Patient‐Provided Samples,” Dermatitis 22, no. 2 (2011): E1–E6. [PubMed] [Google Scholar]
- 3. Wlodek C. and Lovell C. R., “Contact Dermatitis Caused by Ebony Wood,” Contact Dermatitis 71, no. 6 (2014): 381–382. [DOI] [PubMed] [Google Scholar]
- 4. Krenitsky A., Ramsauer K., Hossler E., and Mowad C., “Allergic Contact Dermatitis Following Occupational Exposure to Various Exotic and Domestic Woods,” Contact Dermatitis 81, no. 6 (2019): 477–479. [DOI] [PubMed] [Google Scholar]
- 5. Serrano P., Medeiros S., Quilhó T., Santos R., and Brandão F. M., “Photoallergic Contact Dermatitis to Brosimum Wood,” Contact Dermatitis 58, no. 4 (2008): 243–245. [DOI] [PubMed] [Google Scholar]
- 6. Rajendran M., “Quinones as Photosensitizer for Photodynamic Therapy: ROS Generation, Mechanism and Detection Methods,” Photodiagnosis and Photodynamic Therapy 13 (2016): 175–187. [DOI] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.