Differential Diagnosis for Sporadic Encephalitis in West Africa

• Single most likely diagnosis
  • Herpes: This is the most common cause of sporadic encephalitis in many parts of the world, including West Africa. Herpes simplex virus (HSV) is particularly known for causing severe encephalitis.
• Other Likely diagnoses
  • VZV (Varicella-Zoster Virus): While less common than herpes simplex, VZV can cause encephalitis, especially in individuals with compromised immune systems or during outbreaks.
  • Lymphocytic choriomeningitis: Caused by the LCMV virus, this condition is more commonly associated with meningitis but can lead to encephalitis, particularly in immunocompromised patients.
• Do Not Miss
  • CMV (Cytomegalovirus): Although more commonly associated with congenital infections or immunocompromised states, CMV encephalitis can be severe and is crucial not to miss due to its implications for treatment and prognosis.
• Rare diagnoses
  • Other viral causes such as enteroviruses, arboviruses (like West Nile virus, though more commonly associated with regions outside West Africa), and less common pathogens that might cause encephalitis in specific contexts or outbreaks.

Each of these options has a different level of likelihood based on the region, the patient's immune status, and the specific clinical presentation. However, Herpes stands out as a common and severe cause of encephalitis globally, including in West Africa. CMV is highlighted in the "Do Not Miss" category due to its potential severity and the importance of early diagnosis in immunocompromised patients.