Meningitis Self Learning Flashcards
What is Meningism?
Complex of:
- Headache
- Photophobia
- Vomiting
- Neck stiffness
Meningism is associated with what/
Meningitis
SAH
Bacteraemia
Severe influenza
How does neck stiffness present in meningism?
Passive flexion stiffness
Lateral/rotational stiffness indicated Cervical spine cause
Outline the pathogenesis of meningitis?
- Attachment ot mucosal epithelial cells
- Transgression of mucosal barrier
- Survival in blood
- Entry into CSF
- Production of overt infection without brain infection
How is meningitis classified?
Bacterial, Fungal or Viral
What are the common bacterial pathogens in meningitis?
- Neisseria meningitidis*
- Streptococcus pneumoniae*
- Haemophilius influenzae*
Neonates: E. coli, Group B Strep
What are the common viral pathogens in meningitis?
Enteroviruses
Herpes simplex virus
Mumps
Meningitis is associated with which surgery?
Ventriculo-atrial/peritoneal shunts (10-30%)
Coagulase negative Staphylococci
What are the non-infective causes of meningitis?
Tumour cells in CSF - diagnosed by CSF cytology
Drug reactions
Sarcoidosis/SLE
What are the typical causes of meningism?
Influenza, head and neck infections, UTI, bacteraemia
Subarachnoid haemorrhage
Migraine
Meningitis should always be considered as a diagnosis in what?
Unexplained unconsciousness
What are the risk factors for meningitis?
Recent skull trauma
Alcoholism
Diabetes mellitus
What are the typical symptoms of meningitis?
Meningism - photophobia, neck stiffness, vomoting, headache
Fever
Clouded consciousness
How should a suspected meningitis case be examined?
General - Pyrexia, GCS, Petechiae, rashes
CVS - Pulse rate, BP
Neuro - Focal neurological signs, papilloedema
Kernig’s sign
Chin to chest
What is Kernig’s Sign?
Flex hip - can patient straighten leg?
Cannot straighten hamstring due to spasm? Meningism likely
What investigations should be used for suspected meningitis?
Bloods before antibiotics
Lumbar puncture unless focal signs, papilloedema
PCR
FBC
U+E
What are the contraindications for Lumbar Puncture?
Focal Neurological signs
Papilloedema
Space occupying lesion
In case of papilloedema or focal neurological signs, what should be performed before a lumbar puncture in suspected meningitis?
Head CT to exclude space occupying lesion
What should be recorded when testing the CSF?
Opening pressure
CSF Microbiology
- Gram/ZN stain
- Differential cell count
- Culture (+ mycobacterial/fungal)
- PCR
CSF Biochemistry
- Glucose
- Protein
How CSF factors are assessed in suspected meningitis?
Appearance
Cells
Predominant cell type
Glucose
Protein
How do CSF factors change in bacterial meningitis?
Appearance - Turbid
Cells - Increased
Predominant cell type - Neutrophils
Glucose - Decreased
Protein - Increased
How do CSF factors change in bacterial meningitis?
Appearance - Clear
Cells - Increased
Predominant cell - Lymphocyte
Glucose - Normal
Protein - Moderate increase
Bacterial meningitis due to common bacterial pathogens is typically associated with what?
Nasopharyngeal colonisation
What is key in antibiotic therapy for menigitis?
Ability for agent to penetrate the CSF
What antibiotics are used in meningitis?
Benzylpenicillin
Ceftriaxone
How is meningitis managed?
Vaccinations
Antibiotics (ceftriaxone, benzylpenicillin)
Steroids (dexamethasone - prevent complications)
How does Fulminant Meningococcal Septicaemia present?
Sudden onset:
- LoC
- Fever
- Septicaemic shock
- Renal failure
- DIC
What conditions are associated with Neisseria meningitidies infections?
Meningitis
Fulminant meningococcal septicaemia
Chronic meningococcaemia
How is Meningococcal meningitis/sepsis treated?
Parenteral penicillin then hospital admission
Notified to health protection
What are the most common causes of viral meningitis?
Enteroviruses (echovirus, coxsackie virus)
MMR
HSV
Varicella
In HIV - EBV
How is Viral meningitis managed?
Symptomatic
Immunocompromised: IV Ig
Where is fungal meningitis seen?
Immunocompromised (HIV, diabetics, lymphoma, immunosuppressant drugs)
What are the most common pathogens in fungal meningitis?
Cryptococcus neoformans
How is Cryptococcal meningitis managed?
Amphotericin
Fluconazole
How does meninigitis differ in neonates?
Poorly localised symptoms/signs
More common pathogens: Group B Strep, E. coli, Enteroviruses
How is neonatal meningitis treated?
Ampicillin
Gentamicin/cefotaxime
IV Ig in viral
Chemoprophylaxis in childbirth for high-risk mothers
