Welcome to August…We’ve Survived July!!!

Noon Conf Today:Emergency Radiology

Tomorrow @ 12:15Lunch from Physician’s Resource Group

Viral Meningitis

• Clinical syndrome of meningeal inflammation with negative bacterial cultures in a patient who did not receive antibiotics before lumbar puncture

• Viruses (Enterovirus) most common• Terms aseptic and viral meningitis may be

used synonymously

Terminology

• Meningitis- inflammation of meninges– CSF Pleocytosis

• Encephalitis- inflammation of brain parenchyma– Produces neurologic dysfunction

• Myelitis- Inflammation of spinal cord– Flaccid paralysis and reduced reflexes

Enteroviruses

• Most prevalent in summer months• 90% of cases of viral meningitis• Clinical features: conjunctivitis, pharyngitis,

rash, herpangina, hand-foot-mouth– Rarely may cause CN palsies, flaccid paralysis,

pulm edema

Herpesviruses

• Wide spectrum of illness• Meningitis- – Infants: possibly fever as only symptom– Older children: meningeal findings

• Encephalitis with or without multiorgan involvement– Altered MS, focal deficits, seizures

• Sacral radiculopathy– Urinary retention, constipation, paresthesia, weakness

Arboviruses

• Arthropod or insect vectors (summer months)• St. Louis Encephalitis– “flu-like” sx to fatal encephalitis

• La Crosse (California) encephalitis– may mimic HSV encepalitis

• West Nile Virus– Maculopapular rash in 50% of pts– Peripheral neuropathy or paralysis (adults)

• Western Equine Encephalitis– Neurologic sequelae in infants

Rabies

• Prodrome 2-10 days fever, HA, myalgias, cough, N/V– Hallucinations, nightmares, insomnia

• Neuro deterioration in 1-2wks– Coma and death by 3rd wk

Need for Hospitalization

• Encephalitis or ill-appearance• Need for emperic Abx• Need for IVF or aggressive pain control• Immunocompromised host• Age < 1y/o

Is CT needed prior to LP

• S/S of increased ICP– Altered mental status– Papilledema– Focal neuro deficits

• Other indications– Immune deficiency– CSF shunt or hydrocephalus– CNS trauma– Hx neurosurgery or space-occupying lesion

Provisional Dx of Viral Meningitis

• CSF WBC of <500 cells/microL – >50% Mononuclear cells (lymphs + monos)

• Normal CSF glucose • CSF protein <100 mg/dL • Negative CSF Gram stain • Enterovirus disease in the community• Improvement following LP

Presumed Bacterial Meningitis

• CSF WBC >1000/microL– Neutrophil predominance

• CSF glucose <40• Ill appearance

Emperic Abx

• Low threshold to treat while awaiting cultures• Must treat while awaiting cultures:– Age < 3months– Severely ill– Immunocompromised

• Ceftriaxone and Vancomycin

Emperic Antivirals

• Acyclovir• All pts -CSF pleocytosis with:– Encephalitis, focal findings on exam, imaging, or

EEG• Infants <28 days of age– Vesicles, seizures, lethargy, resp distress,

thrombocytopenia, hypothermia, hepatitis, sepsis-like illness, elevated transaminases

• Immunocompromised

Complications

• Neonates– Encephalitis, viremia, myocarditis, pericarditis,

hepatic failure, DIC, pneumonitis• SIADH

Persistent Sx or Atypical Course

• If symptoms not improving within 1wk consider:– Partially treated meningitis– Fungal, mycobacterial (TB), lyme, rickettsial,

parasitic– Abscess or parameningeal infxn– ADEM– Vasculitis– Malignancy

In viral meningitis, BG normal or slightly reduced, > 40% of serum glucose