VIRAL MENINGITIS Flashcards
1
Q
Common Causes in Acute Meningitis
A
- Enteroviruses (coxsackieviruses, echoviruses, and human enteroviruses 68-71) - Varicella-zoster virus - Herpes simplex virus 2 - Epstein-Barr virus - Arthropod-borne viruses - HIV
2
Q
- most common cause of viral meningitis >85% of cases
- most likely in the summer and fall months (children <15 years)
- PE: careful search for stigmata of enterovirus infection including exanthems, hand-foot-mouth disease, herpangina, pleurodynia, myopericarditis, and hemorrhagic conjunctivitis.
- CSF profile: lymphocytic pleocytosis (100-1000 cells/pL), normal glucose and normal or mildly elevated protein concentration.
- CSF reverse transcriptase PCR (RT-PCR) is the diagnostic procedure of choice
A
Enteroviruses
3
Q
- increasingly recognized as a major cause of viral meningitis in adults
- second most important cause of viral meningitis 5% of total cases
- uncomplicated meningitis: ____-2 Herpes simplex virus} - - HSV encephalitis: ____-1 (90%)
- occurs in ~25-35% of women and ~10-15% of men at the time of an initial (primary) episode of genital herpes.
- Diagnosis is usually by CSF PCR
A
Herpes simplex virus}
4
Q
- Should be suspected in the presence of concurrent chickenpox or shingles
- The frequency as a cause of meningitis is extremely variable, ranging from as low as 3% to as high as 20% in different series
- Diagnosis is usually based on CSF PCR
- Serologic studies complement PCR testing
A
Varicella-zooster virus
5
Q
- May also produce aseptic meningitis, with or without associated infectious mononucleosis.
- Presence of atypical lymphocytes in the CSF or Peripheral blood
- Serum and CSF serology - IgM viral capsid antibodies (VCAs), antibodies to early antigens (Eas), and the absence of antibodies to EBV-associated nuclear antigen (EBNA)
A
Epstein-Barr virus
6
Q
- should be suspected in any patient presenting with a viral meningitis with known or suspected risk factors for HIV infection
- may occur following primary infection with HIV in 5-10% of cases and less commonly at later stages of illness.
- Cranial nerve palsies (CN: V, Vil, or VIII) are more common in HIV meningitis than in other viral infections
- Diagnosis can be confirmed by detection of HIV genome in blood or CSF
A
HIV
7
Q
- should be considered when meningitis occurs in the late winter or early spring, especially in males. (M:F of 3:1)
- presence of parotitis, orchitis, oophoritis, pancreatitis, or elevations in serum lipase and amylase is suggestive
- Diagnosis is typically made by culture of virus from CSF or by detecting IgM antibodies or seroconversion
A
Mumps
8
Q
- be considered when aseptic meningitis occurs in the late fall or winter
- individuals with a history of exposure to house mice (Mus musculus), pet or Lymphocytic choriomeningitis virus laboratory rodents or their excreta.
- Lab clues: Presence of leukopenia, thrombocytopenia, or abnormal liver function tests.
- Diagnosis is based on serology and/or culture of virus from CSF.
A
Lymphocytic choriomeningitis virus
9
Q
CLINICAL MANIFESTATION OF VIRAL MENINGITIS
A
- Immunocompetent adult patients:
+ Headache
+ Fever
+ signs of meningeal irritation coupled with an inflammatory CSF profile - Headache characterized as frontal or retroorbital and frequently associated with photophobia and pain on moving the eyes.
- Nuchal rigidity is present in most cases
Constitutional signs: malaise, myalgia, anorexia, nausea and vomiting, abdominal pain, and/or diarrhea. - Mild lethargy or drowsiness
- Profound alterations in consciousness, do not occur, and suggest the presence of encephalitis or other alternative diagnoses.
10
Q
- most important laboratory test
- Pleocytosis
- normal or slightly elevated protein conc. (0.2- 0.8 g/L [20-80 mg/dt])
- normal glucose conc.
- Normal or mildly elevated opening pressure (100-350 mmH20)
A
CSF Examination
11
Q
has become the single most important method for diagnosing CNS viral infections
A
Polymerase Chain Reaction Amplification of Viral Nucleic Acid
12
Q
- Sensitivity is generally poor.
- Specific viruses may also be isolated from throat swabs, stool, blood, and urine.
A
Viral Culture
13
Q
diagnosis of arboviruses such as WNV
A
Serologic Studies
14
Q
Treatment of almost all cases is primarily symptomatic and includes use of
A
- analgesic
- antipyretics
- antiemetics
15
Q
Tx for Seriously ill HSV patients:
A
- IV acyclovir
- Acyclovir
- Famciclover
- Valacyclovir
