A Rare Co-occurrence of Monkeypox Encephalitis and Neurosyphilis.

Monkeypox (MPOX according to the Centers for Disease Control and Prevention) has been a disease of interest in populations with high-risk sexual behavior. As sporadic outbreaks of MPOX have led to a worldwide spread, it has been declared a public health emergency by the World Health Organization. Here, we describe the case of a 44-year-old male with high-risk sexual behavior who presented with typical rashes of MPOX and altered mental status. MPOX polymerase chain reaction from the skin lesion and cerebrospinal fluid-Venereal Disease Research Laboratory tests were positive, raising the possibility of concomitant infection with neurosyphilis. The patient was treated with tecovirimat and aqueous penicillin G resulting in an improvement in the patient's clinical condition. Our case describes that MPOX has the potential to cause central nervous system manifestations through possibly a direct viral invasion or an immune-meditated insult.