Meningitis

Etiology

  • Inflammation of layers covering brain (meninges)
  • Bacterial: Strep Pneumo, H Flu, Listeria, N Menigitidis
  • Viral: EBV, enterovirus, HSV, VZV, Measels, HIV
  • Fungal: cryptococcus, histoplasmosis, coccidioomycosis, blastomyces
  • Mycobacterial: TB Spirochetes: Lyme, Leptospirosis, Syphillis
  • Rickettsiae: Rocky mountain spotted fever, Typhus (scrub)
  • Parasites: Malaria, Cysticercosis (T Solium)
  • Non-infectious: Collagen vascular disease→ lupus, cancer involving the meninges, post infectious, medications→ NSAIDs, IVIG, other

Risk Factors

  • Strep: living in close quarters (college dorms, barracks), asplenic, immunocompromised
  • Neisseria: Living in close quarters (college dorms, barracks), not vaccinated
  • H Flu: not-vaccinated
  • Listeria: ends of the age spectrum (old or young)
  • Measels: not vaccinated
  • Fungal, Mycobacterial: HIV, compromised by chemotherapy or meds that impair T-Cell function
  • Parasites: exposure in an endemic area, not-using prophylaxis (malaria), eating contaminated pork (T Solium)

Symptoms

  • Photphobia
  • Headache
  • Fever
  • Acute neck stiffness
  • Spectrum from acute confusion to obtundation
  • Generalized illness
  • Fungal, mycobacteriall tend to cause more sub-acute sx

Physical Exam Findings

  • F
  • Neck pain w/paracervical palpation; sometimes wont bend neck--> can raise torso off bed
  • + Kernigs (specific not sensitive)→ pain with passive knee extension when hip flexed to 90; + Brudzinski (specific not sensitive)→ hip and knee flexion occurs w/passive neck flexion
  • + jolt (sensitive not specific)→ worsening ha when patient rotates head back & forth
  • Less common to have focal neurological findings and overall less impaired compared w/encephalitis

Sub-Diseases

Tests

Links