RESUMEN
BACKGROUND: Neurosyphilis is the tertiary stage of Treponema pallidum infection that involves the central nervous system, which occurs within days or weeks after an initial syphilis infection, especially in immunocompromised patients. The diagnosis of neurosyphilis is quite challenging as it is uncommon and often presents with obscure symptoms since any organ system may be involved. CASE PRESENTATION: We describe a case of a 40-year-old African man who is human immunodeficiency virus positive with early neurosyphilis who presented with a stiff neck, headache, confusion, restlessness, and a left-sided chest pain; he did not respond to an empiric treatment of ceftriaxone and fluconazole for meningitis, and tramadol for headache. Ten days after admission, he developed generalized tonic-clonic convulsions; on examination he had ipsilateral facial nerve palsy and an oral ulcer, and responded well to benzathine penicillin treatment. CONCLUSIONS: Laboratory diagnosis of neurosyphilis is challenging because to date there is no single laboratory test which is considered sensitive enough for diagnosis of the disease, especially in resource-limited settings. Clinical judgment is still an important part of diagnosis; and neurosyphilis should be considered a diagnostic differential in patients with Human Immunodeficiency Virus presenting with central nervous system involvement and in other high-risk patients.