Tuberculosis Unveiled: TB Causes, Types, Prevention, Diagnosis, and Treatment

Tuberculosis is the ongoing battle against one of humanity's oldest and deadliest diseases. Mycobacterium tuberculosis infection is the 9th leading cause of death worldwide.

Tuberculosis (TB) continues to pose a significant global health threat, affecting millions of people worldwide. Stay with this blog as we discuss the various aspects of tuberculosis, including its types, causes, signs and symptoms, risk factors, prevention, diagnosis, treatment and government initiative for TB, and the importance of raising awareness to overcome this persistent health challenge.

Understanding Tuberculosis

What is Tuberculosis?

Tuberculosis is a bacterial infection. It caused by Mycobacterium tuberculosis. It primarily affects the lungs but can also target other parts of the body organ, such as the kidneys, spine, and brain. TB spreads through the air when an infected person coughs or sneezes, releasing bacteria-containing droplets that can be inhaled by others nearby.

Types of Tuberculosis

Tuberculosis not only affects lungs but also other organs. Hence broadly it can be categorized as:

1. Pulmonary Tuberculosis:  About 87% of TB cases are of pulmonary tuberculosis. It affects the lungs and is the most common type of Tuberculosis.
2. Extrapulmonary TB: This type of tuberculosis affects organs other than the lungs. Examples of these organs include the lymph nodes, the liver, the gastrointestinal tract, the meninges, the skin, the endometrium, and genitourinary tract, which includes tuberculosis in the bladder.
3. Multidrug-Resistant Tuberculosis (MDR-TB) & Extensively Drug Resistant Tuberculosis (XDR-TB): Both extensively drug-resistant (XDR-TB) and multidrug-resistant (MDR-TB) tuberculosis have become serious variations. MDR-TB is resistant to both of the most effective TB treatments, whereas XDR- TB is also resistant to second-line therapies. Specialised approaches are required to manage and treat the disease because of these drug-resistant types.
   
4. Latent Tuberculosis: Latent tuberculosis infection, in which the germs may be present but not causing any symptoms.

Signs and Symptoms of Tuberculosis

Pulmonary Tuberculosis:

• Persistent cough lasting three weeks or longer
• coughing up phlegm with tints of blood
• Weight loss.
• Mild fever specially in evening
• Loss of appetite

Extrapulmonary Tuberculosis:

This type of tuberculosis affects organs other than the lungs. This is called extrapulmonary tuberculosis. Symptoms vary from person to person from to point of infection site:

• Fever.
• Night sweats.
• Weight loss.
• Loss of appetite
• Tiredness.
• Fatigue.
• Pain near site on infected part (dull aching)

Latent TB infection:

Latent TB infection typically follows primary infection. During this stage, the immune system encapsulates TB germs within the infected tissue, preventing further harm if kept under control. However, the germs persist without causing symptoms. E.g.: Gastrointestinal, Spine etc.

Main Causes of Tuberculosis Infection

1. Contact to Infected Person: Close contact with an infected individual increases the risk of contracting TB.
2. Smoking: Tobacco smoke damages the lungs and weakens the body's ability to ward off TB infection.
   
3. Exposure to Pollution: Exposure to air pollution, including industrial smoke and burning of fuels, increases the risk of TB infection.
4. Pregnancy: Untreated maternal TB can pose risks to both the mother and the unborn child, leading to low birth weight and other complications.
5. Diabetes and Kidney Disease: Conditions like diabetes and chronic kidney disease compromise the immune system, making individuals more vulnerable to TB.
6. Healthcare professional: Healthcare professionals working with TB patients are at increased risk of infection due to occupational exposure.
7. Compromised Immune System: People with weakened immune systems, such as those with HIV/AIDS, are more susceptible to TB.
8. Organ Transplant: Organ recipients can contract TB from donors, particularly if the donor comes from an area with a high TB prevalence.

Preventing Tuberculosis

Prevention is crucial in controlling the spread of tuberculosis. Key preventive measures include:

• Vaccination: The Bacillus Calmette-Guérin (BCG) vaccine provides partial protection against TB, particularly in kids.
• Infection Control: Implementing measures to reduce transmission, such as proper ventilation and respiratory hygiene.
• Early Diagnosis and Treatment: Prompt identification and treatment of TB cases help prevent further spread of the disease.
• Avoiding contact with an infected person and maintaining strong immunity are crucial for tuberculosis prevention.
• Treating patients with latent TB to prevent the development of active cases.
• Monitoring and screening healthcare workers for TB infection.
• Using UV germicidal lamps in high-risk tuberculosis areas to kill airborne bacteria.
• Implementing Direct Observed Treatment (DOT) to ensure patients take medicines consistently and prevent drug-resistant TB.
• Ensuring proper ventilation in indoor spaces.

Diagnosing Tuberculosis 

Diagnosing tuberculosis is a complicated process and it will take a series of tests. A doctor first checks a patient's history and background to see if he or she was exposed to the infection. Then he suggests a series of the tests according to the symptoms to confirm the disease. Following tests suggested if your doctor suspects a TB infection. 

Diagnosis divided in two parts

Direct test:

• Culture techniques: Using culture techniques, you can establish the presence of tuberculosis (TB) and ascertain the drug susceptibility of your sample by cultivating bacteria.
• MTB/NTM PCR
• Molecular Tests (e.g., GeneXpert)
• MIGT

Indirect test:

• Tuberculin Skin Test (TST) Mantoux test
• Interferon-Gamma Release Assays (IGRAs)
• Chest X-ray
• Sputum Smear Microscopy
• TB Spot: T-SPOT technology, a modified version of the enzyme-linked immunospot (ELISPOT) methodology.

TB screening is essential for high-risk individuals in healthcare settings and communities with limited access to care. Methods include symptom checks, chest X-rays, and rapid molecular tests like TB GeneXpert and MTB PCR.

Tests for TB infection - tuberculin skin test (TST, such as the Mantoux test) and interferon- gamma release assay (IGRAs) - are not used for the screening of TB disease.

Treatment of TB

Effective treatment of TB typically involves a combination of antimycobacterial drug taken for several months. It's essential to complete the entire course of treatment to prevent drug resistance and recurrence of the disease like MDR or XDR TB. Killing the bacteria is not an easy task; it requires complete medication for up to 9 months and parallel testing to check the viral load.

If the patient is in the latent stage, they may require a few medications, whereas if the patient is in the active infection period, the treatment regimen may be different. If the patient's report shows drug resistance to first-line drugs, the doctor may suggest second-line drugs.

Government Initiative for TB

Under the National TB Elimination Programme (NTEP), the government provides free diagnostics and medicines for TB patients. The Nikshay Poshan Yojana, launched in 2018, offers TB patients Rs. 500 monthly nutritional support until treatment completion. 

However, achieving TB elimination requires community participation. Hence, the Ministry of Health & Family Welfare initiated the ‘Pradhan Mantri TB Mukt Bharat Abhiyaan’ (PMTBMBA) campaign, encouraging community involvement. Nikshay-Mitras, including individuals, NGOs, and corporations, support TB patients with nutritional supplements, investigations, and vocational aid for at least six months. Launched nationwide by the Hon’ble President on

September 9, 2022, PMTBMBA aims to enhance TB care and move closer to elimination goals.

Conclusion

In conclusion, despite advancements in diagnosis, treatment, and government initiatives, tuberculosis remains a significant global health threat. Efforts to combat TB require a multifaceted approach, including prevention, early diagnosis, effective treatment, and community involvement.