Neurosyphilis in disguise.

Purpose Neurosyphilis can mimic different diseases, not only in its clinical presentation but also on imaging. Treponema pallidum is also known as the "great imitator." Having an ultimate diagnosis of neurosyphilis is quite critical as this can affect management drastically. Herein, we discuss the case of a 69-year-old female who was treated for neurosyphilis, while having an atypical imaging finding of anterior temporal lobe enhancement that simulated an infection with herpes simplex virus (HSV); we also review the available literature on different imaging findings in both the early and late stages of the disease. Methods We performed a literature search using the new PubMed in June 2021. The terms "neurosyphilis", "MRI", and "neuroimaging" were used either alone or in combination with "early neurosyphilis" or "late neurosyphilis". Data on neurosyphilis and imaging findings was mainly derived from review articles, cohort studies, case series, and individual reports. Conclusion Neurosyphilis can present with an extensive variation and different patterns on the MRI, and clinicians must be aware of the wide variety in radiological presentations. Anterior temporal lobe involvement is a rare presentation and requires evaluating for neurosyphilis to prevent a missed diagnosis and treatment.