Deer tick masquerading as pigmented conjunctival lesion

Conjunctival adherence of a tick is an uncommon event with few reports previously cited in the literature. We report a unique case of tick penetration, specifically a black-legged deer tick (Ixodes scapularis), into the conjunctiva.

This patient experienced a 3-week history of unilateral mild ocular pain, decreased vision, and pigmented lesion of her right eye. Slit lamp examination demonstrated a tick attached to the conjunctiva. Pathology confirmed the insect exoskeleton. Visual appreciation of the tick demonstrated probable deer tick larval stage given the shape, size, pigmentation pattern and geographic location of the specimen. Polymyxin-trimethoprim eye drops were prescribed for use three times daily and loteprednol twice daily.

Despite the low risk for Lyme disease, which is endemic to the Adirondack region where the patient was affected, doxycycline was prescribed for prophylaxis. In any case of suspected tick penetration to the ocular surface, immediate ophthalmologic consultation and prompt removal via the method mentioned above is recommended, as well as attention paid to the Infectious Diseases Society of America guidelines regarding prophylaxis.