Tuberculosis (TB) is an infectious disease caused by the bacillus Mycobacterium tuberculosis, which primarily typically affects the lungs (so-called pulmonary TB) but may also involve other organs (extrapulmonary TB), especially in immunocompromised individuals (those who have inborn or acquired immunodeficiency, for example, due to HIV). It is suggested that almost one-third – one-fourth of the world’s population is infected. Nevertheless, it was estimated that approximately 10% of infected individuals develop the disease at some point in their lifetime.
Latent TB is the condition when a person is infected and there is a persistent immune response to that stimulation, what’s been proven by the positive result of the tuberculin skin test, whereas there are no other signs of the disease.
Individuals with latent tuberculosis do not have any symptoms of the disease, chest X-ray shows no abnormalities and they cannot infect the others, so they can go on with their normal everyday activities, although preventive therapy is recommended in order to prevent the reactivation of bacteria. Latent tuberculosis is confirmed by the positive results of a tuberculin skin test.
How to avoid the reactivation of mycobacterial infection
- In order to prevent the development of active tuberculosis a person who has a latent infection should undergo complete prophylactic treatment despite the fact that he/she is asymptomatic.
- A person should also take care of his/her health, treat other medical conditions, avoid stressful situations, have some rest and sleep at least 8 hours a day, maintain a healthy diet rich in nutrients and vitamins, and take in for sports.
- Smoking increases the risk of TB two-threefold. Along with tuberculosis smoking damages lungs and therefore is associated with poor treatment results. If the person who suffers from tuberculosis is smoking he/she is recommended to quit smoking
The infection may lie latent within healed, fibrotic and/or calcific granulomata for the whole life. Under certain circumstances granulomas break down, mycobacteria start to replicate causing the development of the symptomatic disease.
How to avoid spreading mycobacteria
In order to minimize the risk of spreading bacteria good ventilation of the apartment/room should be arranged. A person who has an active disease should
- Take all the medicines according to the prescription and continue therapy as long as necessary;
- See a physician regularly to control the course of the disease and its treatment efficacy;
- Cover the mouth and nose while coughing or sneezing;
- Wash hands afterwards;
- Avoid contacting with other people.
A course of isoniazid for 6-9 months is recommended for the treatment of latent infection and may be used for the prevention of active tuberculosis.
For active disease, the treatment regimen is usually comprised of the initial phase when 3 or more drugs are administered for 2 months in order to stop the bacteria replication and as the result reduce the presence of bacteria in the sputum. Afterward, the treatment continues with the administration of fewer drugs (usually isoniazid and rifampicin) for 4 to 7 months depending on the activity of the disease.
A person should have regular checkups while receiving antituberculosis treatment to check its efficacy and observe and treat possible adverse reactions. The drugs should be taken regularly according to the prescription, otherwise, Mycobacteria may develop drug resistance and become hard to treat, and a person will continue to spread bacteria infecting everyone who is in close contact.
Antituberculosis treatment is known to cause various side effects which vary greatly from person to person and include the following:
- Loss of appetite;
- Dry mouth;
- Sore throat;
- Abdominal pain;
- Orange/red colored urine;
- Prickling, tingling or burning sensation of the fingers and/or toes;
- Joint pain;
- Skin rash/itching;
- Impaired hearing, deafness;
- Joint pain;
- Impairment of vision;
- Purpura or shock;
In order to prevent drug neurotoxicity and development of peripheral neuropathy vitamin B6 (pyridoxine at a dose of 10-25 mg/day) should be administered.
If some of the adverse effects occur acutely and severely impair a person’s well-being the administration of the causative drug should be discontinued and the therapy should be restarted with changed dosages.
Tuberculosis can be treated effectively if a person takes medicines regularly and finishes a complete course of therapy. The latent infection lasts lifelong and an infected person may have an active happy life without the risk of infecting the others once treatment/chemoprophylaxis is completed.