PetriKey

Disease

Bacterial meningitis

Inflammation of meninges with rapid onset

men-in-JY-tis

cnsmeningescsfneck-stiffnessemergency

High-yield clue

Fever, headache, and nuchal rigidity with a neutrophil-rich, low-glucose CSF profile is the core study picture.

Overview

Infection of the membranes surrounding the brain and spinal cord, studied for its age-dependent causative organisms and classic cerebrospinal-fluid pattern. It matters as a rapidly progressive syndrome where recognition vocabulary is heavily tested.

Classification

  • CNS syndrome
  • Age-stratified organism patterns
  • Acute vs chronic framing
  • Pyogenic (bacterial) vs aseptic (viral) contrast

Lab & identification clues

  • CSF with high neutrophils, low glucose, high protein vocabulary
  • Nuchal rigidity, Kernig and Brudzinski sign terms
  • CSF Gram stain and culture concept
  • Petechial/purpuric rash association with meningococcus

Associations

  • Neonates: group B Strep, E. coli, Listeria vocabulary
  • Older children/adults: pneumococcus and meningococcus
  • College-dorm outbreak and vaccine public-health framing
  • Respiratory-droplet transmission for meningococcus

Commonly confused with

  • Viral (aseptic) meningitis
  • Encephalitis

Your notes

Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.

OpenStax: Microbiology 2e organism classification foundationssourceNCBI Bookshelf: Medical Microbiology organism chapterssourceCDC: CDC disease and public-health topic pagessource