Allergic Granulomatous Contact Dermatitis: A Reaction to Metal Particles Used in Ear Lobe Piercing

Abstract

This is an image-based clinical vignette demonstrating a granulomatous reaction to metal particles used in ear lobe piercing in a teenage girl who presented with bilateral lesions on her ear lobes, clinically thought to be keloids. Microscopic examination showed extensive granulomatous inflammation with rare polarizable metal particles seen on H&E-stained sections. The granulomatous inflammation was disproportionately extensive in comparison with the rarity of metal particles triggering the process. The diagnosis of allergic granulomatous contact dermatitis was rendered. This overreaction phenomenon is typical of granulomatous inflammation and this case demonstrates the importance of examination of granulomatous inflammatory lesions under polarized light, especially in the context of negative staining for infectious agents.

Keywords

allergic granulomatous contact dermatitis - necrotizing granulomatous inflammation - metal particles - polarized light - foreign body

Introduction

Allergic granulomatous contact dermatitis is a rare reaction to metal particles in ear lobe piercings, typically presenting as nodular lesions rather than the typical eczematous rash. While nickel is the most common culprit in allergic contact dermatitis, granulomatous reactions are often associated with other metals like palladium or titanium. These reactions can involve a sarcoidal-type granulomatous response, which is characterized by epithelioid granulomas and multinucleate histiocytes.[1] [2]

Case Report

We present the case of a teenage girl (n = 1) who presented with bilateral lesions on her ear lobes, clinically thought to be keloids.

Discussion

Differential diagnoses of granulomatous inflammation include infectious causes such as mycobacterial infections (tuberculosis, mycobacterium avium intracellulare, etc.), fungal infections (e.g., aspergillosis, blastomycosis, etc.), bacteria (e.g., Bartonella henselae in cat scratch disease), Yersinia lymphadenitis, syphilis, and leprosy (Hansen's disease). Noninfectious causes include sarcoidosis, rheumatoid arthritis, foreign-body reactions such as from trauma or surgery, granulomatosis with polyangiitis, and cholesterol granuloma. Granulomatous inflammation can be associated with certain tumors, both benign and malignant. Langerhans cell histiocytosis, chondrodermatitis nodularis helicis, granuloma annulare, and necrobiotic granulomas including necrobiotic xanthogranuloma, rheumatoid nodules, and necrobiosis lipoidica are some other causes.[1] [3] [4] The granulomatous inflammation seen in our patient was disproportionately extensive in comparison with the rarity of metal particles triggering the process. This overreaction phenomenon is typical of granulomatous inflammation ([Figs. 1] and [2]).[1] [5] [6]

Fig. 1 (A–D) A composite of microscopic findings from an H&E-stained section of a patient's ear lobe lesion. Note the necrotizing granulomatous inflammation around foreign particles, suggesting allergic dermatitis, a reaction to metal particles used in ear lobe piercing.

Fig. 2 Rare metal particles were seen on H&E-stained sections (A and B). These particles are showing birefringence under polarized light (C and D). Special stains for organisms were negative.

The formation of cutaneous sarcoid-type allergic contact granuloma is rare and was first reported by Mann et al over 20 years ago in a patient who used gold earrings.[7] González-Pérez et al recently studied the case of a child who developed a sarcoid-type allergic contact granuloma on the ear after wearing several earrings containing a range of metals including palladium.[8] High et al described a granulomatous reaction to titanium alloy in ear piercing in a 68-year-old man.[2] Goossens et al described two cases of sarcoidal-type allergic contact granuloma due to metals in ear piercing, the first to palladium (Pd) only, and the second to Pd and possibly also to other metals. Both the patients developed papulonodular lesions at the helices following ear piercing, which after 3 to 4 weeks became more granulomatous and very resistant to treatment.[9] Examination under polarized light is helpful in detecting polarizable particles and solving the mystery of some cases and saving time and resources chasing other etiologies.

Conclusion

Knowledge of this pathologic entity, noting the anatomic site and the bilateral presentation of this process, is all important in making the diagnosis of allergic granulomatous contact dermatitis. It is important to always include examination under polarized light when dealing with granulomatous inflammation.[3]

Conflict of Interest

None declared.

Author's Contributions

S.B.K. made the diagnosis, wrote the first draft, and prepared composite photo. S.S. performed literature search and edited manuscript.

Compliance with Ethical Principles

None.

• References

• 1 Shah KK, Pritt BS, Alexander MP. Histopathologic review of granulomatous inflammation. J Clin Tuberc Other Mycobact Dis 2017; 7: 1-12
• 2 High WA, Ayers RA, Adams JR, Chang A, Fitzpatrick JE. Granulomatous reaction to titanium alloy: an unusual reaction to ear piercing. J Am Acad Dermatol 2006; 55 (04) 716-720
• 3 Chamani S, Mobasheri L, Rostami Z, Zare I, Naghizadeh A, Mostafavi E. Heavy metals in contact dermatitis: a review. J Trace Elem Med Biol 2023; 79: 127240
• 4 Ahlström MG, Thyssen JP, Wennervaldt M, Menné T, Johansen JD. Nickel allergy and allergic contact dermatitis: a clinical review of immunology, epidemiology, exposure, and treatment. Contact Dermatitis 2019; 81 (04) 227-241
• 5 Garner LA. Contact dermatitis to metals. Dermatol Ther 2004; 17 (04) 321-327
• 6 Casper C, Groth W, Hunzelmann N. Sarcoidal-type allergic contact granuloma: a rare complication of ear piercing. Am J Dermatopathol 2004; 26 (01) 59-62
• 7 Mann RJ, Peachey RDG. Sarcoidal tissue reaction–another complication of ear piercing. Clin Exp Dermatol 1983; 8 (02) 199-200
• 8 González-Pérez R, Ruiz-Carrillo G, Soloeta R. Sarcoid-type allergic contact granuloma caused by earrings in a boy. Actas Dermosifiliogr 2012; 103 (01) 73-74
• 9 Goossens A, De Swerdt A, De Coninck K, Snauwaert JE, Dedeurwaerder M, De Bonte M. Allergic contact granuloma due to palladium following ear piercing. Contact Dermatitis 2006; 55 (06) 338-341

Publication History

Article published online:
24 June 2025