Xanthelasma-like eyelid plaque secondary to periocular <i>Demodex</i> infestation with granulomatous dermatitis

Periocular <i>Demodex</i> infestation is common but exhibits a wide range of clinical presentations. We report a unique case expanding the clinical spectrum of periocular demodicosis. A 61-year-old Caucasian man with a history of multiple cutaneous malignancies presented with a 10 x 6 mm yellow plaque of the left upper pretarsal eyelid for one year associated with intermittent foreign body sensation. Examination demonstrated eyelid margin and lash line involvement with blepharitis, collarettes, and meibomian gland dysfunction. Biopsies of the lesion and eyelid margin were performed and revealed granulomatous dermatitis surrounding numerous <i>Demodex</i> mites. This case illustrates that periocular demodicosis may present as a xanthelasma-like eyelid plaque with granulomatous inflammation, mimicking xanthelasma, amyloidosis, or malignancy. Recognition of this atypical presentation is important, as biopsy of suspicious periocular lesions can establish the diagnosis and allow appropriate treatment.