Neuroretinitis as a Complication of Cat Scratch Disease

In this case report, a patient with neuroretinitis from a Bartonella henselae infection is described, and insights into methods to distinguish this type of case from more common etiologies of optic nerve edema are presented. A 21-year-old female with a history of right monocular vision loss due to amblyopia presented to the emergency department (ED) with occipital headache, fever, dizziness, nasal congestion, and painless blurry vision in the left eye for one day. A lumbar puncture found a slightly high opening pressure but no evidence of meningitis. The patient was diagnosed with a viral illness and discharged with outpatient follow-up. The patient, however, had persistent central vision loss and recurring headaches and returned to the ED. Subsequent ultrasound of the patient's optic nerve revealed significant optic nerve swelling. A new working diagnosis of idiopathic intracranial hypertension was made, and the patient was started on oral acetazolamide. On the next day, she was seen by ophthalmology, and recent scratches from her cat were noted on her arm. She tested positive for B. henselae and was started on doxycycline and rifampin. Nearly two weeks after the initial presentation, a macular star pattern, indicative of neuroretinitis, was noted on the fundoscopic exam. The patient had recovered her vision by three months later. In ED cases with unilateral vision loss, early use of point-of-care ultrasound and infection with B. henselae should always be considered. Early serology testing may be warranted to allow for earlier treatment since classic signs of neuroretinitis may not be apparent at the onset.