Case Presentation: The patient is a 72-year-old male with a medical history of gout and hypertension who presented from an outside hospital with diplopia and muscle cramps. Per patient report, he was sitting at home watching TV when he started noticing double vision, followed by a pressure sensation around his left eye. He did not have any pain with EOM, trauma, decrease in visual acuity, or sensitivity to light. He denied any history of recent travel or tick bites. Workup with MRI brain, MRA head and neck and orbital MRI was negative for stroke. ESR and CRP were normal. He was started on aspirin for concern of posterior circulation TIA with plans for discharge and advised to follow up with ophthalmology. On day of discharge, he noted mild light sensitivity and decreased visual acuity in his left eye and was found to have limited adduction and downward gaze. He was evaluated by ophthalmology and sent home without acute intervention with a diagnosis of binocular vision disorder with diplopia. He then returned to the ED four days later with right sided facial droop and perioral numbness. Differentials included microvascular cranial nerve III palsy, myasthenia gravis, myositis and Lyme disease. Lyme IgG Western Blot and Lyme AB screen were positive. Patient was started on a 4-week course of IV ceftriaxone and discharged home. His visual symptoms and facial droop started to improve within 2 weeks.
Discussion: Lyme disease is a tick-transmitted multisystem inflammatory disease caused by the spirochete Borrelia burgdorferi. With over 25,000 cases reported annually to the CDC, Lyme disease is now the most common vector-borne disease in the United States. Most cases are reported in the high endemic New England and mid-Atlantic states, as well as Minnesota and Wisconsin. The most common vector in the United States is the Ixodes scapularis tick. Acute Lyme neuroborreliosis is the second most frequent clinical manifestation after Erythema migrans. Early LNB generally develops within 2–18 weeks after infection and can be the presenting (or even the only) sign of Lyme disease. The most common manifestations of early LNB are painful meningoradiculitis and lymphocytic meningitis. The diagnosis is based on neurological symptoms suggestive of LNB without other obvious explanations, cerebrospinal fluid pleocytosis and intrathecal antibody production against Borrelia burgdorferi. Various antibiotics: penicillin, ceftriaxone, cefotaxime or doxycycline has shown to be effective in LNB. Recommended treatment duration is 14 days in acute LNB and 21 days in late LNB. Interestingly, in our case, the patient had involvement of the central nervous system evident via physical exam including CN 3 and CN 5 paralysis without any meningeal signs such as headache, AMS, fever or nuchal rigidity. This is what truly made our case unique as compared to other well documented cases of this disease. With a lack of these meningeal signs, it made it lower on the list of differentials when originally working up this case. He also did not originally present with facial nerve palsy, which is a common presentation of this disease.
Conclusions: Neuroborreliosis is a common manifestation of Lyme disease and is often thought of as a diagnosis of exclusion. This is in part due to its varying phenotypes. However, given the increased rates of this disease especially in endemic areas such as the New England and mid-Atlantic states, Lyme disease as a differential for acute neurologic manifestations including involvement of cranial nerves should be considered higher the list of differentials.
