Abstract
Epidemiological trends have demonstrated re-emergence of neurosyphilis in the twenty-first century. As prevalence rises in clinical practice, neurosyphilis must be considered in the differential diagnosis even if initial diagnostic workup is unrevealing, especially in patients with human immunodeficiency virus (HIV). Co-infection of neurosyphilis and HIV can result in atypical presentations. In this report, we discuss a challenging diagnosis of neurosyphilis in a man with HIV who presented with atypical imaging findings and initially negative cerebrospinal fluid (CSF) nontreponemal testing. Our patient underwent repeated CSF evaluation and a comprehensive diagnostic workup, including brain biopsy, to arrive at the appropriate diagnosis. He received antibiotic treatment with excellent outcome. We review typical imaging features of neurosyphilis and highlight other neurological diseases that may mimic these radiographic findings. We discuss CSF testing and interpretation in this high-risk patient population.