Welcome to August… We’ve Survived July!!! Noon Conf Today: Emergency Radiology 12:15 Lunch 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 3 rd 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