Tuberculosis: Symptoms, Diagnosis, Treatment and Prevention

Written by: Dr Revathi Naidu K.Chandrasekaran, Medical Information Officer, MBBS, MScPH (IMU)

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is an ancient human disease that mainly affects the lungs. However, tuberculosis is a multi-systemic disease. The most frequently affected organ systems include the respiratory, gastrointestinal, lymphoreticular, skin, musculoskeletal, central nervous, and reproductive systems.

The stark reality persists: tuberculosis remains the leading cause of death worldwide. According to the World Health Organisation (WHO), approximately 1.3 million people died due to tuberculosis in 2022, while 10.6 million people were affected by tuberculosis. In Malaysia, there were about 78 cases per 100000 population, with a mortality rate of 7.9 per 1000000 population reported in 2022.

Nevertheless, the fundamental truth is that tuberculosis is highly preventable and curable.

Delve into the specifics of pulmonary (lungs) tuberculosis with this article. Read on to deepen your understanding of this crucial aspect of tuberculosis.

How Does Tuberculosis Occur?

Tuberculosis is primarily transmitted through the air from one person to another. In individuals who are infected, bacteria are contained within tiny airborne droplets that are created by the act of sneezing or coughing.

Those who inhale these droplets are referred to as "contacts." Contacts can include individuals who spend significant time with the infectious person, such as family members, friends, or coworkers.

It is important to note that tuberculosis is NOT transmitted by: 

• Handshakes
• Sharing food or beverages
• Touching bed linens or commode seats
• Kissing
• Sharing toothbrushes

Upon exposure to tuberculosis, the contact person may not immediately fall ill. In some instances, the person's immune system successfully eliminates the bacteria, preventing infection or disease development.

In other cases, the immune response may contain the bacteria within the body, resulting in "latent" tuberculosis. Although latent tuberculosis does not cause immediate illness, the bacteria remain viable. At this stage, the person is said to have "tuberculosis infection," a condition that affects up to a quarter of the global population.

In tuberculosis infection, formerly called "latent tuberculosis," the individual is well with no symptoms and cannot spread the infection to others. Effective treatment at this stage can usually prevent the progression to tuberculosis disease.

Tuberculosis disease, formerly known as “active tuberculosis”, occurs when the Mycobacterium tuberculosis bacteria overpower the immune system, leading to an individual falling ill.

Tuberculosis disease may also develop if tuberculosis infection was not fully treated. This is called reactivation tuberculosis and may occur in 5 to 10% of individuals with tuberculosis infection later in life. Those with Human Immunodeficiency Virus (HIV), diabetes mellitus, malnutrition, or individuals taking immunosuppressive medications, such as those used for rheumatoid arthritis, steroids, or cancer chemotherapy, are more susceptible.

What Are the Symptoms of Tuberculosis Disease?

Symptoms include:

• Chronic cough for 3 weeks or longer
• Coughing up blood or sputum
• Evening rise of temperature
• Night sweats
• Weight loss
• Weakness or fatigue

How Is Tuberculosis Diagnosed?

Your doctor would first question your general health and symptoms before conducting a thorough physical examination. Diagnosis is made based on your reported symptoms, physical examination, and investigations.

1. Tuberculin skin test (Mantoux test)

• In individuals newly infected with tuberculosis, the skin test typically yields a positive result within a timeframe of 4 to 10 weeks after exposure to a person who is actively ill with tuberculosis.
• A small quantity of PPD (purified protein derivative) solution is injected just beneath the surface of the skin, typically on the forearm. The solution contains an inactivated portion of the tuberculosis bacteria.
• Following the placement of the test, most individuals who have been previously infected with tuberculosis will exhibit a skin reaction at the injection site characterised by redness or swelling. This reaction typically manifests over 2 to 3 days following the test placement.
• The injection site skin is examined 48 to 72 hours after the test to determine the presence of a swelling (reaction), and the size of the swelling is recorded.
• A swelling greater than 15mm: positive test.
• Some people with a swelling of 5 mm (close contact with someone who has tuberculosis, HIV) or 10mm (recently travelled from a region where tuberculosis is prevalent) are considered to have a positive test.

2. Blood tests

• Interferon-gamma release assays (IGRAs) are used as an option to identify a tuberculosis infection.
• These blood tests may be utilised instead of or in conjunction with the tuberculin skin test.

Notably, individuals who previously received the Bacillus Calmette-Guérin (BCG) vaccine may still undergo a tuberculin skin test. However, BCG vaccination can lead to a false positive reaction. In such cases, a positive reaction could be attributed to the BCG vaccine or an actual tuberculosis bacteria infection.

3. Chest x-ray

• If the tuberculin skin test or blood test is positive, your doctor may request a chest x-ray to determine the presence of tuberculosis disease.

4. Sputum culture

• This requires the patient to cough up “deep” specimen of phlegm from the chest.
• A positive culture of Mycobacterium tuberculosis would confirm the diagnosis of tuberculosis disease.

How Is Tuberculosis Treated?

Tuberculosis infection

Treating tuberculosis infection is a crucial strategy in reducing the risk of progression to tuberculosis disease.

Several drug regimens are available for treating tuberculosis infection, and the choice depends on various factors, including potential medication interactions, side effects, and the likelihood of the patient completing the full course of treatment.

Common regimens include:

• Rifampin daily for 4 months
• Isoniazid plus rifampin daily for 3 months
• Isoniazid plus rifapentine weekly for 3 months
• For those who cannot take rifampin or rifapentine, an alternative is isoniazid daily for 6 or 9 months

Completing the entire course of treatment is paramount. Remember to discuss with your doctor if you have any concerns about the risks and potential side effects. While undergoing treatment, it is critical to refrain from consuming alcohol and taking acetaminophen. Both substances can place an additional strain on the liver, potentially heightening the risk of liver injury from the medications.

Tuberculosis disease

The WHO recommends a standardised anti-tuberculosis regimen consisting of two distinct phases: intensive and continuation phases.

1. Intensive Phase (2 Months / 8 Weeks):
• Isoniazid (INH)
• Rifampicin (RIF)
• Pyrazinamide (PZA)
• Ethambutol (EMB)
2. Continuation Phase (4 Months / 18 Weeks):
• Isoniazid (INH)
• Rifampicin (RIF)

Is Tuberculosis a Public Health Concern in Malaysia?

In Malaysia, the laws mandate the reporting of anyone diagnosed with tuberculosis to the health department. This reporting ensures prompt intervention and collaboration between health department staff, the patient's healthcare provider, and the patient to establish and complete a safe and effective treatment plan.

Directly Observed Therapy (DOT) is a public health program that ensures patients take prescribed tuberculosis medication safely. It involves daily interactions with a healthcare worker who oversees medication intake, including proper swallowing, and assesses for adverse reactions or clinical worsening. This minimises serious side effects, potentially improving cure rates.

Moreover, since 2019, some healthcare facilities in Malaysia have implemented Video-Observed Treatment (VOT), a program recommended by WHO as a new form of DOT. This may be conducted via teleconsultation to monitor patients from a distance.

How to Prevent Tuberculosis?

Tuberculosis infection and transmission can be prevented by following these essential steps.

1. Early detection and treatment

• Seek medical attention promptly if you experience persistent cough, fever, and unexplained weight loss.
• Early treatment for tuberculosis can increase your chances of recovery and prevent the disease's spread.

2. Get tested

• Individuals at increased risk, such as those with HIV or close contact with tuberculosis, should undergo tuberculosis testing.

3. Complete prescribed treatment

• Ensure you complete the entire course of anti-tuberculosis medication as directed by your doctor.

4. Maintain hygiene

• If you have tuberculosis, maintain good hygiene when coughing. This includes avoiding contact with others, wearing a mask, covering your mouth and nose when coughing or sneezing, and appropriately disposing of phlegm and used tissues.

5. Vaccination

• The BCG vaccine, derived from a live strain of Mycobacterium bovis, was developed by Calmette and Guérin as an attenuated vaccine to prevent tuberculosis.
• Since its first human administration in 1921, it is the sole vaccine widely utilised for tuberculosis prevention. The BCG vaccine is the most globally administered vaccine, having reached over 3 billion individuals, primarily through routine newborn immunisation as recommended by the WHO guidelines.

As part of the National Immunisation Programme in Malaysia, the BCG vaccine is administered at birth on the upper left arm of babies. If you have observed a scar on your left arm, it is most likely a result of the BCG vaccine. Instead of concealing this mark, consider it a symbol of protection. That seemingly inconspicuous scar signifies the shield the vaccine provides against tuberculosis.

Make an Appointment at Pantai Hospitals

In the global fight against tuberculosis, each individual plays a vital role in shaping a healthier and Tuberculosis-free world tomorrow. By joining hands in the fight against tuberculosis, we can break the chain of transmission, eliminate stigma, and pave the way for a future where no one lives under the shadow of this preventable and treatable disease.

Together, let us turn awareness into action because a tuberculosis-free world starts with each of us.

Get in touch with us to book an appointment today if you have any concerns or questions regarding your reproductive health.

Please contact the Health Screening Centre at your nearest Pantai Hospital for health screening appointments.

Pantai Hospital has been accredited by the Malaysian Society for Quality in Health (MSQH) for its commitment to patient safety and service quality.