What is TB meningitis?
Tuberculosis (TB) meningitis or TBM is a severe form of tuberculosis. This occurs when the bacteria Mycobacterium tuberculosis, which normally infects the lungs, and spreads to the lymph nodes and the bloodstream. The bacteria then travel to the meninges, or the protective layers that cover the brain, and eventually infect the brain tissues. If not treated immediately, the infection can cause a rise in the pressure inside the skull. This may result in nerve and brain tissue damage.
TB Meningitis is more prevalent in children than in adults. People who are infected with tuberculosis and/or human immunodeficiency virus (HIV) are prone to suffering from TB meningitis. People who have a weak immune system are also prone to developing this disease.
TB meningitis progresses in three stages, as developed by the British Medical Council. Symptoms become more complicated as the disease gradually infects the body. As a person progresses through the three TB meningitis stages, the likelihood of permanent brain damage and death increases.
TB Meningitis Stages of Severity
Stage 1 – Non-specific symptoms
At this stage, a person infected with TB meningitis will manifest symptoms that can be associated with a lot of different diseases. A person can start with one of these symptoms and eventually manifest more as the disease progresses. Symptoms for stage 1 TB meningitis include:
- Irritability
- Fatigue
- Persistent headache
- Malaise
- Low-grade fever
- Nausea
- Vomiting
Stage 2 – Altered consciousness with minor focal neurological symptoms
At this stage, the patient will start to display signs and symptoms of dysfunction in the central nervous system (brain and the spinal cord).
- Meningism – There is an inflammation in the protective barrier of the brain which causes headache, neck stiffness, and light sensitivity. There may also be nausea and vomiting.
- Focal neurological deficits – Which may include cranial nerve palsies, weakness over the limb or a side of the body
- Confusion – The person infected with TB meningitis might not recognize the time or place they are in.
- Abnormal Involuntary Movements – Tremors in the hands and other parts of the body. The person might also experience involuntary, repetitive, brief, irregular movements in the body (chorea). Dystonia or involuntary contractions in the mouth and face such as teeth grinding and difficulty talking might be experienced.
Stage 3 – Almost no level of consciousness with focal neurological symptoms
At this stage, TB meningitis has caused severe inflammation in the brain. Complications such as hydrocephalus or build-up of fluid in the brain and cerebral vasculitis or inflammation in the blood vessel walls of the brain are likely to occur.
- Coma – A state of prolonged unconsciousness wherein the person cannot be awakened.
- Seizures – Jerky movements in the body caused by an uncontrolled electric disturbance in the brain.
- Delirium – Reduced awareness and responsiveness, which can appear as being disoriented to place and time, unable to speak or put thoughts together clearly, and lapses of memory.
- Abnormal Posturing – Involuntary flexion of the arms and legs.
- Abnormal Movements – The person might experience tremors, chorea, and or dystonia.
As a person goes through TB meningitis stages, the chances of surviving becomes slimmer and slimmer. This is why TB meningitis needs to be diagnosed as early as possible.
Diagnosing TB meningitis
Treatment
Treatment for TB meningitis can take a year or longer depending on different factors such as severity, co-infection with HIV, and the patient’s response. Multidrug-resistant tuberculosis might also present complications in treatment.
Doctors may use a combination of antibacterial drugs to kill off the bacteria and lessen any inflammation in the meninges. Use of corticosteroids might also help with inflammation in the brain.
A person infected with TB meningitis is at risk of developing the disease again so it might require a lifetime of monitoring once the person has recovered.
Key takeaway
TB meningitis is a severe form of TB infection where the bacteria has entered the bloodstream and reached the brain. TB meningitis goes in three stages of severity. As the disease increases in severity, the less likely a patient will survive. TB meningitis is treatable especially if detected early.
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