herpes encephalitis
| Headline | |
|---|---|
| Etiology | HSV1 - 90% of cases HSV2 - more common in babies <3 months obligate intracellular virus that enters via infecting nasopharyngeal cells into the sensory branch of lingual nerve then ascends to trigeminal ganglion and remains latent for a lifetime. |
| Epidemiology | |
| Clinical presentation | affects temporal and frontal lobe mainly fever, headache, altered consciousness |
| Pathogenesis | |
| Investigations: | Radiology: (copied from Radiopaedia) - bilateral asymmetrical involvement of the limbic system, medial temporal lobes, insular cortices and inferolateral frontal lobes → hyperintense T2 signal in the medial temporal lobes, inferior frontal lobes and insula - basal ganglia sparing Lumbar puncture: - lymphocytosis - HSV PCR sensitivity 96–98%, specificity 95–99% EEG |
| Management: | IV aciclovir - 10mg/kg is CNS dose - anyone on aciclovir should be well hydrated |