Ocular tuberculosis is a rare eye infection due to the same bacteria that cause tuberculosis (TB) in your lungs. Symptoms are similar to other eye infections. It’s curable, and getting treatment can prevent severe complications.

The same bacteria that cause TB in your lungs can also cause it in your eyes. This rare condition is known as “ocular tuberculosis.”

TB is a highly infectious disease, most common in developing countries, particularly countries in Africa and South Asia. Globally, more than 1.7 billion people might have TB. But ocular TB is rare.

Because ocular TB often looks like other types of eye diseases, it’s hard to know how many people worldwide have this condition. But some studies estimate that up to 0.5% of people in the United States with an eye condition called uveitis may develop it due to ocular TB. In Iraq, where TB is common, more than 11% of people with uveitis may have ocular TB.

This article explains ocular TB — its causes, symptoms, diagnosis, treatment, complications, and other important aspects.

Many people with ocular TB don’t have any symptoms. For those that do, symptoms vary from person to person but usually relate to eye inflammation. Some people have inflammation in one eye, while others have it in both. Common symptoms include:

Ocular TB is due to infection from Mycobacterium tuberculosis, the same bacteria that cause pulmonary (lung) TB. The infection can reach the eyes through three main routes:

  1. Primary: Bacteria can infect the eye through direct contact with eye structures, such as your eyelids or the membrane that covers your eye.
  2. Secondary: Bacteria can travel through the bloodstream from the infected tissues (such as the lungs) into your eyes. This is the most common mechanism.
  3. Hypersensitivity reaction: Your eye can have a reaction to molecules in dead bacterial cells.

An eye doctor (ophthalmologist) will first perform a thorough eye exam to diagnose ocular TB. They’ll ask you about your medical history, for example, previous history of TB or HIV. They may also perform or order different tests, including:

Treatment of ocular TB is usually the same as for other types of this TB. In addition to an ophthalmologist, you’ll likely connect with an infectious disease specialist to treat your TB.

Doctors typically use four antibiotics to treat the infection. You’ll take them in two phases:

Phase 12 monthsrifampicin
Phase 24 monthsrifampicin

You may also receive corticosteroids with your treatment.

Antibiotics used to treat TB may have potentially serious side effects, including liver damage. Tell your doctor about new or alarming symptoms during your treatment, for example:

Learn more about TB treatment.

Completing your treatment course is important

It’s important to stay current with and to complete your course of antibiotics for TB, even if you no longer have symptoms. Not following your antibiotic schedule could cause symptoms to return or the bacteria to become drug-resistant.

Getting treatment for inflammation in your eyes can prevent potentially severe complications, such as:

TB treatments can themselves can cause eye complications. For example, ethambutol can cause optic neuritis. Your ophthalmologist will contact you frequently during treatment to help detect and treat any complications early on.

Without treatment, ocular TB can lead to severe complications, including vision loss. But TB treatment is usually effective and can help completely resolve eye inflammation and other symptoms.

Let’s review a few questions people with ocular TB and their loved ones frequently ask their doctors.

Is ocular tuberculosis contagious?

Ocular TB isn’t contagious. But if you have pulmonary TB (active form) with ocular TB, you can transmit the infection to others. Speak with a doctor to determine whether your particular condition is contagious.

How common is ocular tuberculosis?

In the United States, ocular TB is rare. But it may be more common in other countries where TB infection is more common. It’s hard to estimate exactly how common it is because it can be frequently confused with other eye conditions.

Can ocular TB cause blindness?

Without treatment, ocular TB can result in permanent structural changes to the eyes, potentially resulting in vision loss or blindness. TB treatment is usually effective at preventing eye-related complications.

Ocular TB is a rare condition resulting from infection by the same bacteria that cause other types of TB, but it specifically affects the eyes. Although it can start in the eyes, it’s more common from bacteria using your bloodstream to travel from your lungs to your eyes.

To diagnose ocular TB, a doctor will perform a series of eye tests and a blood or skin test for TB. Treatment is similar to that of pulmonary TB.

Getting treatment can prevent severe complications from ocular TB, including blindness. Modern treatment is typically effective and can completely reverse the negative health effects and prevent further complications.