DOXY do, or DOXY Don't? Syphilis and doxycycline post-exposure prophylaxis: A case report

Area of Science:

• Infectious Diseases
• Neurology
• Public Health

Background:

• Syphilis is re-emerging in Europe with atypical presentations.
• Early diagnosis of syphilis is crucial to prevent severe complications.

Purpose of the Study:

• To report a case of neurosyphilis masked by DoxyPEP.
• To raise awareness about DoxyPEP's potential impact on syphilis diagnosis.

Main Methods:

• Case report of a young man who has sex with men (MSM).
• Clinical presentation included persistent headaches and forehead swelling.
• Diagnosis of neurosyphilis confirmed despite a recent negative syphilis test.

Main Results:

• Neurosyphilis was diagnosed in a patient using DoxyPEP.
• DoxyPEP is suspected to have delayed diagnosis by altering the antibody response.
• Atypical symptoms mimicked other conditions like giant cell arteritis (GCA).

Conclusions:

• DoxyPEP may hinder syphilis detection and influence disease progression.
• Further research is needed on DoxyPEP's effects on syphilis, antimicrobial resistance, and the microbiome.
• Clinicians should consider DoxyPEP use when diagnosing syphilis, especially in MSM.