Tuberculosis (TB),TB Cause,TB Symptoms,TB Risk Factors,TB Treatment

Tuberculosis

Tuberculosis (TB) is a disease caused by the bacteria Mycobacterium Tuberculosis, which are airborne pathogen,meaning that this bacterial infection spreads through air from person to person when a person with TB(whose lungs are affected) coughs,spit,sneezes,laughs or talks.TB generally affects the lungs but can also affect other parts of body. 

There are two types:-

• Latent TB infection:- When people breathe in bacterial spores they become infected and the bacteria lives inside the host without making them sick because of the inherent immune system which is called Latent TB infection. People with Latent TB infection do not have any symptom & are not a potential threat to others.

• Active TB Disease:- When a person with Latent TB infection has a weak immune system (due to other health problems), the TB bacteria becomes      active & multiply in the body and resulting in evident symptoms of TB and are active vectors.
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Cause of Tuberculosis:-

TB is caused by acid fast bacteria Mycobacterium Tuberculosis & first discovered by German microbiologist Robert Koch in 1882. It is non motile rod-shaped small bacillus and does not retain any bacteriological stain due to high lipid content (e.g.Mycolic acid) in its cell wall,hence acid-fast staining (Ziehl-Neelsen Staining)is used. M.Tuberculosis is highly aerobic bacteria so requires oxygen to grow & they divides every 15-20 hours.Due to presence of mycolic acid in its cell wall they can withstand weak disinfectants & can survive in a dry state for weeks. Many Strain of these bacteria able to developing a resistance against antibiotics that fail to kill them completely which is vary dangerous for human being .If it not treated properly, TB disease can be fatal.

Symptoms :-

TB bacteria most commonly grow in the lungs but can also attack any part of body as the kidney,bone,spine & brain & can cause symptom such as :-

• A prolonged bed cough producing sputum  (occasionally small amount of blood).
• Pain in the chest.

Other Symptoms

• Weakness or Fatigue
• Weight loss
• No appetite
• chills & fever
• Sweating at night

TB Risk Factors:-

Anyone can affected with TB,but people at high risk generally fall into following categories:-

• People recently infected with TB bacteria.
• People with suppress immune power due to other disease & malnutrition.
• You have spent time with a person with TB disease.
• You have visited areas or country where TB disease is vary common.

You have a higher chance of getting TB disease once infected if :-    

• You have HIV infection.
• You have younger than 5 year child.
• You have other health problems that make it hard for your body to fight disease.
• You smoke cigarettes or abuse alcohol & drugs.
• You were not treated correctly for latent TB infection or active TB disease in the past.

Treatment :-

Treatment of Latent TB infection:

Latent TB infection means TB bacteria live in body but they are not sick because bacteria are not active.However if bacteria become active & multiply in the body,LTBI convert to active TB disease. For this reason,WHO recommended following regimens for  LTBI treatment to prevent its develop in TB disease:-

• 6 or 9 month Isoniazid daily.
• 3-month Rifapentine + Isoniazid weekly.
• 3 or 4 month Isoniazid + Rifampicin daily.
• 3 or 4 month Rifampicin alone daily.

Treatment for Active TB Disease:

TB bacteria become active & multiply in the body,if the immune system can't stop them from growing & finally person become sick with symptoms of TB which is called Active TB Disease.There are 10 drugs currently approved by FAD for treating TB disease. WHO recommended First-Line Anti-TB agent for treating fresh/new TB patient (Drug susceptible TB i.e TB which is not resistant to any of the drug) &  called as treatment regimens which are:-

• Isoniazid (INH)
• Rifampicin (RIF)
• Pyrazinamide (PZA)
• Ethambutal (EMB)

For these patients, the WHO recommended that they should have 6 to 9 month of TB drugs treatment.This should consist of a two month "Initial" treatment phase followed by a four month "Continuation"phase.

• For Initial Treatment Phase-INH+RIF+PZA+EMB per day for two month.
• For Continuation Phase- INH+RIF per day for 4 to 6 month.

It is very important that TB patients complete all dose of medicine which are exactly prescribed. If patient do't take the drugs correctly,the TB bacteria that are still alive may become resistant to those drugs & further treatment is very harder & expensive.