title: Neurosyphilis with optical involvement in an immunocompetent patient: a case report.
abstract: BACKGROUND
  Neurosyphilis became a rare disease after the introduction of antibiotics. The resurgence of syphilis in association with human immunodeficiency virus infection in the past decades increased the incidence of this tertiary form of the disease. However, in immunocompetent patients neurosyphilis remains uncommon and accurate diagnosis is challenging as the clinical presentation is unspecific and the validity of supportive laboratory tests is unclear.
  
  
  METHODS
  We describe the case of a 60-year-old man who presented with a 6-month clinical picture of depression-like symptoms and recent sudden unilateral blindness. Medical history uncovered a primary syphilitic event 20 years before. The investigation led to the diagnosis of neurosyphilis with optical involvement in a patient who did not present with any signs of secondary syphilis. Treatment with penicillin G and topical steroids resulted in significant clinical improvement and resolution of the visual loss.
  
  
  CONCLUSIONS
  In the well-established natural history of syphilis, primary syphilis is almost always followed by manifestation of the secondary form, which in turn precedes a period of latency. This case emphasizes the need for a high index of suspicion of neurosyphilis in an immunocompetent patient with nonspecific neuropsychiatric manifestations and an atypical course of syphilis infection.
authors.affiliation: Internal Medicine Service, Saint John Hospital Center, Porto, Portugal.
authors.forename: Rui Paulo
authors.initials: RP
authors.lastname: Rodrigues
authors.forename: Nuno
authors.initials: N
authors.lastname: Correia
authors.forename: António Vieira
authors.initials: AV
authors.lastname: Lopes
keywords: neurosyphilis; parenchymatous neurosyphilis; syphilis