Meningitis and encephalitis

Meningitis, encephalitis and stroke for medical students preparation slide:

Meningitis and encephalitis: causes, symptoms, investigations, complications and treatment

Introduction and definition of meningitis:

• Meningitis is the inflammation of the CSF and the meninges. 
• If the infection spreads into the brain it is termed meningoencephalitis.
• Usually is caused by an infection, but chemical meningitis also may occur in response to a nonbacterial irritants introduced into the subarachnoid space.

Types of meningitis:

• Infectious meningitis can be broadly divided into:
• Acute pyogenic (usually bacterial),
• Aseptic (usually viral), and 
• Chronic (usually tuberculous, spirochetal, or cryptococcal) subtypes.

Acute Pyogenic Meningitis (Bacterial Meningitis)

• In neonates:

• • Escherichia coli and the group B streptococci; 

• In adolescents and in young adults:

• • Neisseria meningitidis 

• In older individuals: 

• • Streptococcus pneumoniae and Listeria monocytogenes.

How do people get Bacterial Meningitis?

Bacteria are spread through direct contact with secretions from the nose or throat of an infected person.

People who qualify as close contacts of a person with meningitis caused by N. meningitidis are:

• Family and household contacts    
• Child or nursery school contacts
• Anyone exposed to patient’s oral secretions

Signs and Symptoms of meningitis in under 2 years age

• Fever
• Headache
• Stiff neck
• Inactivity
• Vomiting
• Poor feeding
• Seizures
• May be hard to detect in infants

Signs and Symptoms of meningitis in over 2 years age

• High fever
• Headache, Stiff neck
• Nausea and vomiting
• Sensitivity to light
• Confusion
• Sleepiness
• Petechiae that spreads rapidly
• Seizures

Diagnosis & Treatment of meningitis:

Early diagnosis and treatment is important.

Signs of meningism

Kernig’s Test 

Brudzinski’s Test 

Diagnosed via lumbar puncture (spinal tap).

Check for bacterial growth in the spinal fluid.

Imaging –CT and MRI.

Treatment of meningitis:

Antibiotics: administration based on bacteria found

Broad spectrum: (later narrowed down to specific antibiotic)

• Ampicillin
• Cephalosporins (3rd generation)
• Vancomycin/linezolid
• Meropenem
• Fluoroquinolones

Bed rest 

Plenty of fluids 

Complications of meningitis:

• Advanced bacterial meningitis can lead to brain damage, coma, and death.
• Survivors can suffer long-term  hearing loss, mental retardation, paralysis, and seizures.