What is Meningeal Tuberculosis?
Tuberculosis (TB) is a contagious, airborne disease that typically affects the lungs. TB is caused by a bacterium called Mycobacterium tuberculosis. If the infection is not treated quickly, the bacteria can travel through the bloodstream to infect other organs and tissues.
Sometimes, the bacteria will travel to the meninges, which are the membranes surrounding the brain and spinal cord. Infected meninges can result in a life-threatening condition known as meningeal tuberculosis. Meningeal tuberculosis is also known as tubercular meningitis or TB meningitis.
Risk factors for Meningeal Tuberculosis
TB and TB meningitis can develop in children and adults of all ages. However, people with specific health problems are at greater risk of developing these conditions.
Risk factors for TB meningitis include having a history of:
- excessive alcohol use
- weakened immune system
- diabetes mellitus
TB meningitis is rarely found in the United States because of high vaccination rates. In low-income countries, children between birth and 4 years of age are most likely to develop this condition.
Symptoms of Meningeal Tuberculosis
At first, symptoms of TB meningitis typically appear slowly. They become more severe over a period of weeks. During the early stages of the infection, symptoms can include:
- low-grade fever
As the disease progresses, the symptoms will become more serious. Classic symptoms of meningitis, such as stiff neck, headache, and light sensitivity, are not always present in meningeal tuberculosis. Instead, you may experience the following symptoms:
- nausea and vomiting
Diagnosing Meningeal Tuberculosis
Your doctor will perform a physical exam and ask you about your symptoms and medical history.
Your doctor may order more tests if they think you have symptoms of TB meningitis. These may include a lumbar puncture, also known as a spinal tap. They’ll collect fluid from your spinal column and send it to a laboratory for analysis to confirm your condition.
Other tests your doctor may use to evaluate your health include:
- biopsy of the meninges
- blood culture
- chest X-ray
- CT scan of the head
- skin test for tuberculosis (PPD skin test)
Complications of Meningeal Tuberculosis
The complications of TB meningitis are significant, and in some cases life-threatening. They include:
- hearing loss
- increased pressure in the brain
- brain damage
Increased pressure in the brain can cause permanent and irreversible brain damage. Call your doctor right away if you experience vision changes and headaches at the same time. These could be a sign of increased pressure in the brain.
Treatment of Meningeal Tuberculosis
Four drugs are typically used to treat TB infection:
TB meningitis treatment includes these same medications, except for ethambutol. Ethambutol does not penetrate well through the lining of the brain. A fluoroquinolone, such as moxifloxacin or levofloxacin, is typically used in its place.
Your doctor may also prescribe systemic steroids. Steroids will reduce complications associated with the condition.
Depending on the severity of the infection, treatment may last as long as 12 months. In some cases, you may need treatment in the hospital.
Prevention of Meningeal Tuberculosis
The best way to prevent TB meningitis is to prevent TB infections. In communities where TB is common, the Bacillus Calmette-Guérin (BCG) vaccine can help control the spread of the disease. This vaccine is effective for controlling TB infections in young children.
Treating people with nonactive or dormant TB infections can also help control the spread of the disease. Nonactive or dormant infections are when a person tests positive for TB, but doesn’t have any symptoms of the disease. People with dormant infections are still capable of spreading the disease.
Outlook for people with Meningeal Tuberculosis
Your outlook will depend on the severity of your symptoms and how quickly you seek treatment. An early diagnosis allows your doctor to provide treatment. If you receive treatment before complications develop, the outlook is good.
The outlook for people who develop brain damage or stroke with TB meningitis is not as good. Increased pressure in the brain strongly indicates a poor outlook for a person. Brain damage from this condition is permanent and will impact health over the long term.
You can develop this infection more than once. Your doctor will need to monitor you after you’re treated for TB meningitis so they can detect a new infection as early as possible.