What is TB Meningitis? Everything You Need to Know

Tuberculous meningitis, or TB meningitis, is a type of meningitis that causes the membranes around the brain or spinal cord, also known as the meninges, to become inflamed. The inflammation of the meninges is caused by a type of bacteria called Mycobacterium tuberculosis, which infects the membranes and develops the infection over time. The swelling of the membrane usually causes headache, high fever, and a sudden stiff neck.

It may take days or even years for the first signs of TB meningitis to be noticed, making it difficult to be diagnosed.

It is possible for anyone to develop TB meningitis but it is more likely to occur in people with weakened immunity and young children.  It is more common in developing countries where TB is still endemic.

TB meningitis causes

TB meningitis may result from a person inhaling the bacteria from a person infected with tuberculosis. It may also affect a person who is already infected with tuberculosis.

Symptoms of TB meningitis

Depending on the immunity of the individual, the symptoms of TB meningitis usually develop slowly but become much more noticeable or severe as time passes. TB meningitis causes the following:

• Chronic or recurring headaches
• Weight loss
• Fatigue
• Body weakness or muscle pains
• Appetite loss
• Symptoms of concomitant pulmonary disease such as cough may be present

Once the infection becomes more severe, the following symptoms may be noticed:

• Stiff neck
• Confusion and mental status changes
• Vomiting
• Seizures
• Focal neurological signs

Because of the slow, gradual nature of the disease, TB meningitis may become difficult to diagnose and requires treatment as soon as the possible symptoms are observed.

Risk factors

Though TB meningitis is more common in certain age groups and locations, people of all ages can develop it. Factors that can increase the chance of developing TB meningitis are as follows:

• TB of the lungs (pulmonary tuberculosis)
• Weakened immune system
• HIV/AIDS
• Diabetes
• Poor living conditions
• Excessive drinking of alcoholic beverages

The following people have a higher chance of getting diagnosed with the disease:

• Unvaccinated infants and children who have come in close contact with family who were born in a country with high TB incidence
• People with jobs that involve having close contact with infected TB patients or animals

Diagnosis

During the assessment or check up, the doctor will ask about the patient’s symptoms and medical history, followed by a physical exam.

The doctor must perform further tests to confirm if a patient is positive for the disease.

A chest x-ray and a CT or MRI scan of the head are usually done. Definitive work up includes a lumbar puncture, also known as spinal tap, which is when the doctor collects spinal fluid from the lower back in order to directly investigate the cause of meningitis. A brain biopsy is usually not necessary.

The doctor will also check for conditions that can suppress your immunity (e.g. diabetes, HIV/AIDS) as addressing such will be key to treatment.

How to prevent TB meningitis

Vaccination is an effective way of preventing this disease. BCG, the vaccine for TB, is routinely recommended to all newborns. It prevents the development and lowers the severity of the different forms of TB. Though the vaccine is distributed all throughout the Philippines, TB remains a significant problem because of ongoing community transmission, gaps in diagnosis, and poor treatment compliance.

Having your children and yourself vaccinated against TB infections will prevent any severe complications of TB in the body.

How treatment works

Early signs of TB meningitis are difficult to diagnose because of its slow progression and nonspecific presentation. However, early treatment will aid in improving one’s recovery.

•  Hospital admission is a must. The doctor needs to properly diagnose and test you. Close observation and monitoring is also warranted.
•  Patients will take anti-TB medications. Pulmonary TB and TB meningitis require the same types of antibiotics as they are caused by the same causative agent. The treatment period usually lasts around nine months to one year, however, may be significantly longer if drug-resistant TB is present.
•  Treatment should be completed. Full and timely compliance with prescribed medications is a must to prevent treatment failure and antibiotic resistance. If this occurs, it will be much more difficult to cure the infection and can lead to serious complications.

Key takeaway

TB meningitis causes a bacterial infection in the membranes surrounding the brain and spinal cord. It is quite common in developing countries with high TB and HIV incidence. The disease causes headaches, stiff neck, as well as tiredness, and appetite loss. Symptoms like vomiting and seizures may also occur once the infection becomes severe.

It may take months, sometimes years, to diagnose the disease. Proper and consistent treatment in a hospital is required to combat the infection.

Learn more about Infectious Diseases here.