VIRAL MENINGITIS Flashcards
The most common cause of viral meningitis?
Enteroviruses (EV)
- Enteroviruses (EV) are the most common cause of viral meningitis, accounting for >85% of cases
- CSF reverse transcriptase PCR (RT-PCR) is the diagnostic procedure of choice and is both sensitive (>95%) and specific (>100%).
- Treatment is supportive, and patients usually recover without sequelae.
The major cause of viral meningitis in adults, and overall, the second most important cause of viral meningitis?
HSV meningitis
What is the most common cause of HSV strain that is implicated in adult HSV meningitis?
HSV-2
- In adults, the majority of cases of uncomplicated meningitis are due to HSV-2, whereas HSV-1 is responsible for 90% of cases of HSV encephalitis
Therapeutic regimen for viral meningitis?
Oral or IV acyclovir
*IV Acyclovir (15–30 mg/kg per day in three divided doses) followed by an oral drug such as Acyclovir (800 mg 5x daily), Famciclovir (500 mg TID), or Valacyclovir (1000 mg TID) for a total course of 7–14 days
TRUE OR FALSE: In adults, the prognosis for full recovery from viral meningitis is POOR?
FALSE.
In adults, the prognosis for full recovery from viral meningitis is EXCELLENT
Presence of_________ in the CSF or peripheral blood is suggestive of EBV infection
Atypical lymphocytes
- EBV infections may also produce aseptic meningitis, with or without associated infectious mononucleosis.
_____ meningitis should be suspected in the presence of concurrent chickenpox or shingles.
VZV meningitis
The single most important method for diagnosing CNS viral infections
Amplification of viral-specific DNA or RNA from CSF using PCR amplification
TRUE OR FALSE: The sensitivity of CSF cultures for the diagnosis of viral meningitis and encephalitis is generally POOR.
TRUE
Which of the following symptoms is not typically associated with viral meningitis?
A) Headache
B) Photophobia
C) Profound confusion or coma
D) Retroorbital pain
Answer: C) Profound confusion or coma
Rationale: Viral meningitis is usually associated with mild lethargy or drowsiness, but profound confusion, stupor, or coma suggests encephalitis or another alternative diagnosis.
Which of the following does not suggest a diagnosis of viral meningitis?
A) Headache and photophobia
B) Lymphocytic pleocytosis in CSF
C) Low CSF glucose concentration
D) Normal or mildly elevated opening pressure in CSF
Answer: C) Low CSF glucose concentration
Rationale: Viral meningitis typically presents with normal glucose levels in the CSF. Low CSF glucose is more suggestive of fungal, tuberculous, or bacterial infections.
What is the most common cause of viral meningitis?
A) HSV-1
B) Enteroviruses
C) HIV
D) Varicella-zoster virus (VZV)
Answer: B) Enteroviruses
Rationale: Enteroviruses account for >85% of viral meningitis cases. These include echoviruses and coxsackieviruses.
Which of the following findings in CSF analysis is most suggestive of viral meningitis?
A) Polymorphonuclear (PMN) cell predominance
B) Increased protein concentration (>1 g/L)
C) Lymphocytic pleocytosis with normal glucose levels
D) Markedly elevated opening pressure (>500 mmH₂O)
Answer: C) Lymphocytic pleocytosis with normal glucose levels
Rationale: CSF in viral meningitis typically shows lymphocytic pleocytosis, normal or slightly elevated protein, and normal glucose. A low glucose concentration suggests bacterial, fungal, or tuberculous meningitis.
A 25-year-old patient presents with aseptic meningitis. PCR testing detects HSV DNA in the CSF. Which virus is most likely responsible?
A) HSV-1
B) HSV-2
C) EBV
D) CMV
Answer: B) HSV-2
Rationale: HSV-2 is the leading cause of HSV meningitis in adults. HSV-1 is more commonly associated with HSV encephalitis.
Which virus is known to cause aseptic meningitis associated with infectious mononucleosis?
A) HSV-1
B) EBV
C) HIV
D) Arbovirus
Answer: B) EBV
Rationale: EBV can cause aseptic meningitis, often in the setting of infectious mononucleosis. Atypical lymphocytes in CSF or blood suggest EBV infection.
