Case Presentation: A 75 YO woman with HTN presented to her optometrist with a one-week history of painless, blurred vision in her left eye. Her history was notable for a febrile illness without rash 2 months prior. She was advised to go to the ED where MRI and CT imaging showed no acute abnormalities and labs revealed an elevated ESR of 33 mm/hr. Seen 2 weeks later by Neuro-Ophthalmology, the patient was assessed to have asymmetric bilateral optic neuropathy with disc edema and disc/peripapillary hemorrhages, bilateral vision loss (left eye predominantly), and a left relative afferent pupillary defect. Serology revealed positive IgM and IgG Lyme antibodies which was confirmed on western blot analysis. The patient was then started on PO Doxycycline 100 mg BID. 10 days later, she presented to the ED with new-onset right eye visual defects. Upon presentation to the ED, oral doxycycline was discontinued, and she was started on 1g IV methylprednisolone Q24 hr along with IV ceftriaxone 2g Q24 hr. Labs on admission were unremarkable, vital signs were stable, and physical exam outside of the aforementioned ocular pathology was benign. Ophthalmology was consulted and based on their recommendation a lumbar puncture was performed which found an elevated CSF protein and glucose with a normal cell count and differential. CSF culture and PCR revealed no detected bacteria organisms nor viral DNA/RNA. CSF serology was positive for antibodies to Borrelia burgdorferi. Based on the clinical presentation and lab-work, the patient was diagnosed with Lyme optic neuritis. On day 4 of admission without vision changes, the patient was discharged with a PICC line to continue IV ceftriaxone and started on a 15-day prednisone taper.

Discussion: With the prevalence of Lyme disease expected to rise over the next century, it becomes prudent to be familiar with one of the more uncommon presentations of the disease: ocular Lyme (1). Various ocular manifestations of Lyme exist including follicular conjunctivitis, uveitis, and optic neuritis (2,3). Rarely, as in this case, ocular Lyme disease can present as unilateral, painless vision loss (4). When ocular Lyme disease is suspected, diagnosis can be made by a two-tiered system of enzyme-linked immunosorbent assay (ELISA) followed by Western blot (5). To confirm CNS Lyme disease, positive CSF Lyme antibodies or CSF PCR studies are the gold standard. Recommended antibiotic treatment of Lyme neuroborreliosis is 3 weeks of a CNS penetrating beta-lactam administered IV or 2-3 weeks of oral doxycycline (6).

Conclusions: When early pathognomonic presentations such as erythema migrans are not found, recognition of the less common neurologic presentations of Lyme disease can aid in diagnosis and treatment. Here we present a case of Lyme optic neuritis to increase awareness among practitioners of the ocular presentations of neuroborreliosis, as well as highlight the value of adding Lyme disease to the differential in presentations of non-specific ocular pathology in Lyme-endemic areas.