Meningitis – Detailed Explanation

Definition: Meningitis is the inflammation of the meninges, the protective membranes that cover the brain and spinal cord. It can be life-threatening if not treated promptly, especially bacterial meningitis.

---

Types of Meningitis:

1. Bacterial Meningitis (Most serious):
   • Caused by bacteria like Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae.
   • Requires immediate antibiotic treatment.
   • Can lead to brain damage, hearing loss, or death if untreated.
2. Viral Meningitis:
   • More common and usually less severe.
   • Caused by viruses like enteroviruses, HSV (Herpes Simplex Virus), mumps, measles.
   • Usually self-limiting; supportive care is enough in most cases.
3. Fungal Meningitis:
   • Rare; seen mostly in people with weakened immune systems.
   • Caused by fungi like Cryptococcus.
   • Requires antifungal medications.
4. Parasitic or Amoebic Meningitis:
   • Very rare but often fatal (e.g., Naegleria fowleri).
5. Non-infectious Meningitis:
   • Caused by autoimmune diseases, cancers, certain drugs, or head injury.

---

Common Symptoms:

• Severe headache
• Fever
• Neck stiffness
• Photophobia (sensitivity to light)
• Nausea and vomiting
• Confusion or altered mental status
• Seizures
• Sleepiness or difficulty waking
• In babies: poor feeding, bulging fontanelle, high-pitched crying

---

Diagnosis:

• Lumbar puncture (spinal tap) – checks cerebrospinal fluid (CSF) for signs of infection.
• Blood tests
• CT scan or MRI – if brain swelling is suspected.

---

Treatment:

• Bacterial: Intravenous antibiotics and corticosteroids.
• Viral: Supportive treatment (fluids, pain relief); antivirals in severe cases.
• Fungal: Antifungal medication.
• Hospitalization is often required, especially for bacterial cases.

---

Prevention:

• Vaccines:
  • Meningococcal vaccine
  • Pneumococcal vaccine
  • Hib (Haemophilus influenzae type b) vaccine
• Good hygiene practices.
• Prompt treatment of ear or sinus infections.

---

Prognosis:

• Bacterial meningitis can cause permanent complications or death if not treated early.
• Viral meningitis generally has a good recovery.

---