A 90-year-old female was referred for evaluation of a suspicious choroidal lesion in the left eye. The patient’s best-corrected visual acuity was 20/40 OD (right eye) and 20/50 OS (left eye), without a relative afferent pupillary defect. Her intraocular pressures were 15 mmHg OD and 14 mmHg OS. Her extraocular motilities were full. Unknowing to the patient, she was incidentally found to have an engorged tick actively feeding upon her right upper eyelid, adjacent to an eyelid hidrocystoma, which was discovered on slit lamp examination (Figure 1). She was noted to have bilateral upper eyelid dermatochalasis; otherwise, there was no associated edema, pain, ptosis, madarosis, or distortion of the right eyelid architecture. She reported that she was in her usual state of health, and review of systems was negative for any recent fevers, chills, fatigue, new rashes, or joint pains. Furthermore, she denied any visual disturbances, diplopia, pain, itching, or ocular irritation. The tick had not been noticed by the patient and her family. The tick was carefully removed at the slit lamp with forceps to ensure complete removal, and submitted to the Connecticut State Department of Public Health for analysis. Given the engorged size of the tick, it was postulated that the parasite had been present and feeding for many hours, although its exact feeding duration was unknown, and the patient was prescribed doxycycline 200 mg as a single oral dose for post-exposure prophylaxis against Lyme disease [1]. The specimen was identified as a slightly engorged adult female Ixodes scapularis tick, also known as a blacklegged tick or deer tick. The tick tested positive for the bacterium Anaplasma phagocytophilum, which can result in anaplasmosis. The patient was recommended to follow-up with her primary care physician and to monitor for other symptoms suggestive of tick-borne illness. She was subsequently followed-up at 1-week, 1-month, and 10-months post-tick removal and did not report development of any signs or symptoms of tick-borne disease. The adjacent eyelid hidrocystoma was excised. The patient’s originally presenting choroidal lesion was found to be a choroidal nevus that was managed with observation.

The Ixodes scapularis tick is known to transmit several pathogens, including Borrelia burgdorferi, A. phagocytophilum, and Babesia microti. Current guidelines recommend antibiotic prophylaxis therapy in areas highly endemic for Lyme disease when an Ixodes tick has been attached for ≥36 hours and when prophylaxis can be started within 72 hours. A limitation of our report is that the exact feeding duration was unknown. Routine prophylaxis is not recommended to prevent other rickettsial disease, such as anaplasmosis or babesiosis [1]. Anaplasmosis typically presents with nonspecific symptoms including fever, headache, fatigue, nausea, and myalgias, and abnormal laboratory results such as leukopenia, thrombocytopenia, and elevated liver enzymes [2]. Potential ocular complications, though extremely rare, include Bell’s palsy, optic neuritis, pupil abnormalities, and ophthalmoplegia [3],[4],[5]. Treatment for suspected anaplasmosis consists of empirical doxycycline for 10 days [1]. Previous case reports of tick bite infestations of the eyelid are associated with localized pain, erythema, swelling, infection, and pigmentary changes [6]. This is an unusual case where the patient presented asymptomatically, and the parasite had gone unnoticed by the patient and her family. The salivary secretions of ticks contain anesthetic, anti-hemostatic, and anti-inflammatory agents, which allow for suppression of symptoms [6],[7]. Careful removal of the tick is essential to prevent further complications. Removal with forceps may be difficult, as forceful pressure can result in regurgitation of infectious toxins by the tick and further disease transmission [6]. En bloc removal, with excision of the tick and the surrounding tissue, may allow for complete removal [6]. Tick removal may also be performed with chemical agents such as liquid dish soap; the use of other chemical agents, including nail polish and gasoline, have demonstrated questionable efficacy [8],[9]. This case further demonstrates the importance of a comprehensive periorbital examination to prevent further systemic complications of tick-borne illness.

In conclusion, healthcare providers should always perform a thorough skin exam to detect unusual lesions, foreign bodies, or even organisms that may evade the notice of patients and their caregivers. Patients may present with ticks feeding on areas of the body as conspicuous as the eyelid.