"GRE/SWI: may demonstrate blooming if haemorrhagic (rare in neonates, common in older patients)"
"Herpes simplex (HSV) encephalitis, or herpes simplex virus encephalitis (HSVE), is the most common cause of fatal sporadic fulminant necrotising viral encephalitis and has characteristic imaging findings 12."
"Herpes simplex virus encephalitis has an incidence of 1-4 cases per million population annually, making it the most common cause of sporadic viral encephalitis in high-income countries. HSV accounts for 50-75% of identified viral encephalitis cases 19. Childhood and adult herpes encephalitis are usually due to HSV-1 (90%) with the rest due to HSV-2 5. There is no particular age, sex, or seasonal predilection."
"Herpes simplex virus encephalitis has an incidence of 1-4 cases per million population annually, making it the most common cause of sporadic viral encephalitis in high-income countries. HSV accounts for 50-75% of identified viral encephalitis cases 19. Childhood and adult herpes encephalitis are usually due to HSV-1 (90%) with the rest due to HSV-2 5. There is no particular age, sex, or seasonal predilection."
"Herpes simplex virus encephalitis has an incidence of 1-4 cases per million population annually, making it the most common cause of sporadic viral encephalitis in high-income countries. HSV accounts for 50-75% of identified viral encephalitis cases 19. Childhood and adult herpes encephalitis are usually due to HSV-1 (90%) with the rest due to HSV-2 5. There is no particular age, sex, or seasonal predilection."
"HSV encephalitis demonstrates a bimodal age distribution with peaks under 20 years old and over 50 years old with the highest peak between 60-64 years 20."
"Diagnosis is established with PCR of CSF, although the combination of the clinical scenario, CSF demonstrating pleocytosis (may be absent in ~20% 9) and elevated protein, and appropriate imaging is usually highly suggestive and permits commencement of treatment 12."
"HSV is an obligatory intracellular virus. Primary infection of the oropharyngeal or nasopharyngeal mucosa results in the virus entering the olfactory bulb or trigeminal ganglion and remaining there. Reactivation in the case of immunosuppression, trauma, or other stresses can result in herpes encephalitis or, less commonly, the brainstem. HSV has a high affinity for limbic systems, with bilateral but asymmetric involvement of the temporal lobes being most common 12,13."
"HSV is an obligatory intracellular virus. Primary infection of the oropharyngeal or nasopharyngeal mucosa results in the virus entering the olfactory bulb or trigeminal ganglion and remaining there. Reactivation in the case of immunosuppression, trauma, or other stresses can result in herpes encephalitis or, less commonly, the brainstem. HSV has a high affinity for limbic systems, with bilateral but asymmetric involvement of the temporal lobes being most common 12,13."
"Post HSV autoimmune encephalitis develops in approximately 27% of patients, most commonly NMDAR antibody autoimmune encephalitis 21."
"Post HSV autoimmune encephalitis develops in approximately 27% of patients, most commonly NMDAR antibody autoimmune encephalitis 21."
"other viral encephalitides: many can have very similar appearances and are difficult to separate clinically, and the diagnosis usually requires PCR 4"
"human herpesvirus 6 (HHV-6) encephalitis"
"Herpes simplex virus encephalitis has an incidence of 1-4 cases per million population annually, making it the most common cause of sporadic viral encephalitis in high-income countries. HSV accounts for 50-75% of identified viral encephalitis cases 19. Childhood and adult herpes encephalitis are usually due to HSV-1 (90%) with the rest due to HSV-2 5. There is no particular age, sex, or seasonal predilection."
"HSV encephalitis demonstrates a bimodal age distribution with peaks under 20 years old and over 50 years old with the highest peak between 60-64 years 20."
"Epstein-Barr virus (EBV) encephalitis"
Expected headings
"Complications"
"Herpes simplex virus encephalitis has an incidence of 1-4 cases per million population annually, making it the most common cause of sporadic viral encephalitis in high-income countries. HSV accounts for 50-75% of identified viral encephalitis cases 19. Childhood and adult herpes encephalitis are usually due to HSV-1 (90%) with the rest due to HSV-2 5. There is no particular age, sex, or seasonal predilection."
"Non-specific prodromal symptoms such as fever, headache, nausea, and malaise typically precede neurological features, which may include focal deficits, seizures, and altered or decreased consciousness 12."
"Evidence of haemorrhage is common in the affected brain parenchyma, especially with the use of SWI, due to cortical and subcortical necrosis; however, this is nearly always petechial in nature 18. Frank intracerebral haemorrhage is very rare 17,18, and intraventricular haemorrhage 15,16 or subarachnoid haemorrhage 15 is exceedingly rare."