2019-09-04

Tuberculosis (TB), infectious disease that is caused by the tubercle bacillus, Mycobacterium tuberculosis. In most forms of the disease, the bacillus spreads slowly and widely in the lungs, causing the formation of hard nodules (tubercles) or large cheeselike masses that break down the respiratory tissues and form cavities in the lungs. Blood vessels also can be eroded by the advancing disease, causing the infected person to cough up bright red blood.
During the 18th and 19th centuries, tuberculosis reached near-epidemic proportions in the rapidly urbanizing and industrializing societies of Europe and North America. Indeed, “consumption,” as it was then known, was the leading cause of death for all age groups in the Western world from that period until the early 20th century, at which time improved health and hygiene brought about a steady decline in its mortality rates. Since the 1940s, antibiotic drugs have reduced the span of treatment to months instead of years, and drug therapy has done away with the old TB sanatoriums where patients at one time were nursed for years while the defensive properties of their bodies dealt with the disease.
Today, in less-developed countries where population is dense and hygienic standards poor, tuberculosis remains a major fatal disease. The prevalence of the disease has increased in association with the HIV/AIDS epidemic; an estimated one out of every four deaths from tuberculosis involves an individual coinfected with HIV. In addition, the successful elimination of tuberculosis as a major threat to public health in the world has been complicated by the rise of new strains of the tubercle bacillus that are resistant to conventional antibiotics. Infections with these strains are often difficult to treat and require the use of combination drug therapies, sometimes involving the use of five different agents.

TYPES OF TUBERCULOSIS- 

Doctors make a distinction between two kinds of tuberculosis infection: latent and active.


* Latent TB - the bacteria remain in the body in an inactive state. They cause no symptoms and are not contagious, but they can become active.
* Active TB - the bacteria do cause symptoms and can be transmitted to others.
About one-third of the world's population is believed to have latent TB. There is a 10 percent chance of latent TB becoming active, but this risk is much higher in people who have compromised immune systems, i.e., people living with HIV or malnutrition, or people who smoke.
TB affects all age groups and all parts of the world. However, the disease mostly affects young adults and people living in developing countries. In 2012, 80 percent of reported TB cases occurred in just 22 countries.

What Causes Tuberculosis ? 


Tuberculosis is an infection caused by bacteria. It's spread through the air—when an infected person coughs, sneezes, laughs, etc. However, it is not easy to become infected with tuberculosis. Usually, a person has to be close to someone with TB disease for a long period of time. TB is usually spread between family members, close friends, and people who work or live together. TB is spread most easily in closed spaces over a long period of time.
Most cases of active TB result from the activation of latent TB infections or old infections in people with impaired immune systems. People with clinically active TB will often but not always display symptoms and can spread the disease to others.

What Are Symptoms and Signs of Tuberculosis?

You may not notice any symptoms of illness until the disease is quite advanced. Even then the symptoms -- loss of weight, loss of energy, poor appetite, fever, a productive cough, and night sweats -- might easily be blamed on another disease.
• Only about 10% of people infected with M. tuberculosis ever develop tuberculosis disease. Many of those who suffer TB do so in the first few years following infection. However, the bacillus may lie dormant in the body for decades.
• Although most initial infections have no symptoms and people overcome them, they may develop fever, dry cough, and abnormalities that may be seen on a chest X-ray.
• This is called primary pulmonary tuberculosis.
• Pulmonary tuberculosis frequently goes away by itself, but in more than half of cases, the disease can return.
• Tuberculous pleuritis may occur in some people who have the lung disease from tuberculosis.
• The pleural disease occurs from the rupture of a diseased area into the pleural space, the space between the lung and the lining of the chest and abdominal cavities. This is often quite painful since all of the pain fibers of the lung are located in the pleura.
• These people have a nonproductive cough, chest pain, and fever. The disease may go away and then come back at a later date.
• In a minority of people with weakened immune systems, TB bacteria may spread through their blood to various parts of the body.
• This is called miliary tuberculosis and produces fever, weakness, loss of appetite, and weight loss.
• Cough and difficulty breathing are less common.
• Generally, return of dormant tuberculosis infection occurs in the upper lungs. Symptoms include
• common cough with a progressive increase in production of mucus and
• coughing up blood.
• Other symptoms include the following:
• fever,
• loss of appetite,
• weight loss, and
• night sweats.
• Some people may develop tuberculosis in an organ other than their lungs. About a quarter of these people usually had known TB with inadequate treatment. The most common sites include the following:
• lymph nodes,
• genitourinary tract,
• bone and joint sites,
• meninges, and
• the lining covering the outside of the gastrointestinal tract.


How Is Tuberculosis Diagnosed?


TB can be detected through a skin test or a TB blood test.
The skin test is done by injecting a small amount of fluid called tuberculin into the skin in the arm. You will be told to return within 48 to 72 hours to have a healthcare worker check the arm to see if a bump or an induration (thickening)  of the skin has developed. These may be difficult to feel and an experienced healthcare worker should examine the reaction. The healthcare worker will measure the bump or induration and tell you if your reaction to the test is positive or negative. If it's positive, it usually means you have been infected with the TB germ. It does not tell whether you have developed clinically active TB disease.
The TB blood test measures how your immune system reacts to the germs that cause TB. If you have a positive test for TB infection, it only means that you have been infected with TB germs. It does not tell whether you have developed clinically active TB disease. You will be given other tests, such as a chest X-ray and a check of your sputum (coughed up mucus), to see whether you have clinically active TB disease.

How Is TB Treated?
Treatment for TB depends on whether a person has clinically active TB disease or only TB infection.
If you have become infected with TB, but do not have clinically active TB disease (this is called latent TB), you should get preventive therapy. This treatment kills germs that are not doing any damage right now, but could so do in the future. The most common preventive therapy is a daily dose of isoniazid (INH) taken as a single daily pill for 6 to 9 months.
If you have active TB disease you will probably be treated with a combination of several drugs for 6 to 12 months. You may only have to stay a short time in the hospital, if at all, and can then continue taking medication at home. After a few weeks, you can probably even return to normal activities and not have to worry about infecting others.
The most common treatment for active TB is isoniazid INH plus three other drugs—rifampin, pyrazinamide and ethambutol. You will probably begin to feel better only a few weeks after starting to take the drugs.
It is very important that you continue to take the medicine correctly (regularly and under medical supervision) for the full length of treatment. If you are being treated in a public clinic you may be asked to take your medicines in the presence of a healthcare worker who will ensure that you have done so. This is called Directly Observed Therapy (DOT).

 

ROLE OF NUTRITION IN TUBERCULOSIS- 

 

An essential dietary nutrient is a substance that a person needs to consume in order to live, grow and be healthy. Nutrients are required to regulate body processes and build and repair tissues and thereby promote health and prevent disease. Macronutrients (protein, carbohydrate and fat) are generally consumed in large amounts. Carbohydrate and some fat are converted to energy, while protein and some fat are used to make structural and functional components of human tissue. Micronutrients (vitamins and minerals) are consumed in small amounts and are essential for metabolic processes. Macronutrients and micronutrients work together to contribute to tissue regeneration and cellular integrity.

Malnutrition is a general term that refers to either overnutrition or undernutrition or both. Undernutrition refers to a state when the nutritional status of the person is suboptimal and thereby health and growth may be limited. Undernutrition may be due to illness that impairs nutrient intake and metabolism, or result from inadequate intake of macronutrients, micronutrients or both. 

 

Undernutrition is commonly associated with illness and infections such as gastrointestinal disorders and malabsorption, pneumonia, TB and HIV. Food insecurity can be a cause of malnutrition, as can alcohol misuse and illicit drug use, and a number of other conditions.

The association between TB and undernutrition has long been known. TB makes undernutrition worse and undernutrition weakens immunity, thereby increasing the likelihood that latent TB will develop into active disease. Most individuals with active TB are in a catabolic state and experience weight loss and some show signs of vitamin and mineral deficiencies at diagnosis . Weight loss among those with TB can be caused by several factors, including reduced food intake due to loss of appetite,

 

MACRONUTRIENTS- 

Macronutrient requirements in active TB

Active TB, like other infectious diseases, is likely to increase energy requirement, and data on the actual level of increase in energy requirements caused by HIV infection may be used as a guide. Studies show that subjects who receive food supplements during TB treatment tend to gain more weight compared with those not receiving food supplements, but the increase in weight gain has not been associated with improvement of TB treatment outcomes. 

There is currently no evidence to suggest that the proportion of dietary energy from macronutrients (e.g. protein, carbohydrate and fat), otherwise known as macronutrient distribution, is different for people with active TB than for those without TB. It is generally recommended that all people consume approximately 15–30% of energy as protein, 25–35% as fat and 45–65% as carbohydrate. 

 

MICRONUTRIENTS- 

Micronutrient requirements in active TB

Low circulating concentrations of micronutrients, such as vitamins A, E and D, and the minerals iron, zinc and selenium have been reported from cohorts of patients beginning treatment for active TB. These usually return to normal after 2 months of appropriate TB treatment. Since studies have not been done on dietary intake near the time of diagnosis, it is unclear whether the low concentrations are related to low dietary intake, to metabolic processes or to the disease itself. It is unknown whether the observed return to normal concentrations is dependent on the quality of dietary intake

 

World Tuberculosis Day “Nature is that lovely lady to whom we owe polio, leprosy, smallpox, syphilis, tuberculosis, cancer.

Tuberculosis (TB), infectious disease that is caused by the tubercle bacillus, Mycobacterium tuberculosis. In most forms of the disease, the bacillus spreads slowly and widely in the lungs, causing the formation of hard nodules (tubercles) or large cheeselike masses that break down the respiratory tissues and form cavities in the lungs. Blood vessels also can be eroded by the advancing disease, causing the infected person to cough up bright red blood.
During the 18th and 19th centuries, tuberculosis reached near-epidemic proportions in the rapidly urbanizing and industrializing societies of Europe and North America. Indeed, “consumption,” as it was then known, was the leading cause of death for all age groups in the Western world from that period until the early 20th century, at which time improved health and hygiene brought about a steady decline in its mortality rates. Since the 1940s, antibiotic drugs have reduced the span of treatment to months instead of years, and drug therapy has done away with the old TB sanatoriums where patients at one time were nursed for years while the defensive properties of their bodies dealt with the disease.
Today, in less-developed countries where population is dense and hygienic standards poor, tuberculosis remains a major fatal disease. The prevalence of the disease has increased in association with the HIV/AIDS epidemic; an estimated one out of every four deaths from tuberculosis involves an individual coinfected with HIV. In addition, the successful elimination of tuberculosis as a major threat to public health in the world has been complicated by the rise of new strains of the tubercle bacillus that are resistant to conventional antibiotics. Infections with these strains are often difficult to treat and require the use of combination drug therapies, sometimes involving the use of five different agents.

TYPES OF TUBERCULOSIS- 

Doctors make a distinction between two kinds of tuberculosis infection: latent and active.


* Latent TB - the bacteria remain in the body in an inactive state. They cause no symptoms and are not contagious, but they can become active.
* Active TB - the bacteria do cause symptoms and can be transmitted to others.
About one-third of the world's population is believed to have latent TB. There is a 10 percent chance of latent TB becoming active, but this risk is much higher in people who have compromised immune systems, i.e., people living with HIV or malnutrition, or people who smoke.
TB affects all age groups and all parts of the world. However, the disease mostly affects young adults and people living in developing countries. In 2012, 80 percent of reported TB cases occurred in just 22 countries.

What Causes Tuberculosis ? 


Tuberculosis is an infection caused by bacteria. It's spread through the air—when an infected person coughs, sneezes, laughs, etc. However, it is not easy to become infected with tuberculosis. Usually, a person has to be close to someone with TB disease for a long period of time. TB is usually spread between family members, close friends, and people who work or live together. TB is spread most easily in closed spaces over a long period of time.
Most cases of active TB result from the activation of latent TB infections or old infections in people with impaired immune systems. People with clinically active TB will often but not always display symptoms and can spread the disease to others.

What Are Symptoms and Signs of Tuberculosis?

You may not notice any symptoms of illness until the disease is quite advanced. Even then the symptoms -- loss of weight, loss of energy, poor appetite, fever, a productive cough, and night sweats -- might easily be blamed on another disease.
• Only about 10% of people infected with M. tuberculosis ever develop tuberculosis disease. Many of those who suffer TB do so in the first few years following infection. However, the bacillus may lie dormant in the body for decades.
• Although most initial infections have no symptoms and people overcome them, they may develop fever, dry cough, and abnormalities that may be seen on a chest X-ray.
• This is called primary pulmonary tuberculosis.
• Pulmonary tuberculosis frequently goes away by itself, but in more than half of cases, the disease can return.
• Tuberculous pleuritis may occur in some people who have the lung disease from tuberculosis.
• The pleural disease occurs from the rupture of a diseased area into the pleural space, the space between the lung and the lining of the chest and abdominal cavities. This is often quite painful since all of the pain fibers of the lung are located in the pleura.
• These people have a nonproductive cough, chest pain, and fever. The disease may go away and then come back at a later date.
• In a minority of people with weakened immune systems, TB bacteria may spread through their blood to various parts of the body.
• This is called miliary tuberculosis and produces fever, weakness, loss of appetite, and weight loss.
• Cough and difficulty breathing are less common.
• Generally, return of dormant tuberculosis infection occurs in the upper lungs. Symptoms include
• common cough with a progressive increase in production of mucus and
• coughing up blood.
• Other symptoms include the following:
• fever,
• loss of appetite,
• weight loss, and
• night sweats.
• Some people may develop tuberculosis in an organ other than their lungs. About a quarter of these people usually had known TB with inadequate treatment. The most common sites include the following:
• lymph nodes,
• genitourinary tract,
• bone and joint sites,
• meninges, and
• the lining covering the outside of the gastrointestinal tract.


How Is Tuberculosis Diagnosed?


TB can be detected through a skin test or a TB blood test.
The skin test is done by injecting a small amount of fluid called tuberculin into the skin in the arm. You will be told to return within 48 to 72 hours to have a healthcare worker check the arm to see if a bump or an induration (thickening)  of the skin has developed. These may be difficult to feel and an experienced healthcare worker should examine the reaction. The healthcare worker will measure the bump or induration and tell you if your reaction to the test is positive or negative. If it's positive, it usually means you have been infected with the TB germ. It does not tell whether you have developed clinically active TB disease.
The TB blood test measures how your immune system reacts to the germs that cause TB. If you have a positive test for TB infection, it only means that you have been infected with TB germs. It does not tell whether you have developed clinically active TB disease. You will be given other tests, such as a chest X-ray and a check of your sputum (coughed up mucus), to see whether you have clinically active TB disease.

How Is TB Treated?
Treatment for TB depends on whether a person has clinically active TB disease or only TB infection.
If you have become infected with TB, but do not have clinically active TB disease (this is called latent TB), you should get preventive therapy. This treatment kills germs that are not doing any damage right now, but could so do in the future. The most common preventive therapy is a daily dose of isoniazid (INH) taken as a single daily pill for 6 to 9 months.
If you have active TB disease you will probably be treated with a combination of several drugs for 6 to 12 months. You may only have to stay a short time in the hospital, if at all, and can then continue taking medication at home. After a few weeks, you can probably even return to normal activities and not have to worry about infecting others.
The most common treatment for active TB is isoniazid INH plus three other drugs—rifampin, pyrazinamide and ethambutol. You will probably begin to feel better only a few weeks after starting to take the drugs.
It is very important that you continue to take the medicine correctly (regularly and under medical supervision) for the full length of treatment. If you are being treated in a public clinic you may be asked to take your medicines in the presence of a healthcare worker who will ensure that you have done so. This is called Directly Observed Therapy (DOT).

 

ROLE OF NUTRITION IN TUBERCULOSIS- 

 

An essential dietary nutrient is a substance that a person needs to consume in order to live, grow and be healthy. Nutrients are required to regulate body processes and build and repair tissues and thereby promote health and prevent disease. Macronutrients (protein, carbohydrate and fat) are generally consumed in large amounts. Carbohydrate and some fat are converted to energy, while protein and some fat are used to make structural and functional components of human tissue. Micronutrients (vitamins and minerals) are consumed in small amounts and are essential for metabolic processes. Macronutrients and micronutrients work together to contribute to tissue regeneration and cellular integrity.

Malnutrition is a general term that refers to either overnutrition or undernutrition or both. Undernutrition refers to a state when the nutritional status of the person is suboptimal and thereby health and growth may be limited. Undernutrition may be due to illness that impairs nutrient intake and metabolism, or result from inadequate intake of macronutrients, micronutrients or both. 

 

Undernutrition is commonly associated with illness and infections such as gastrointestinal disorders and malabsorption, pneumonia, TB and HIV. Food insecurity can be a cause of malnutrition, as can alcohol misuse and illicit drug use, and a number of other conditions.

The association between TB and undernutrition has long been known. TB makes undernutrition worse and undernutrition weakens immunity, thereby increasing the likelihood that latent TB will develop into active disease. Most individuals with active TB are in a catabolic state and experience weight loss and some show signs of vitamin and mineral deficiencies at diagnosis . Weight loss among those with TB can be caused by several factors, including reduced food intake due to loss of appetite,

 

MACRONUTRIENTS- 

Macronutrient requirements in active TB

Active TB, like other infectious diseases, is likely to increase energy requirement, and data on the actual level of increase in energy requirements caused by HIV infection may be used as a guide. Studies show that subjects who receive food supplements during TB treatment tend to gain more weight compared with those not receiving food supplements, but the increase in weight gain has not been associated with improvement of TB treatment outcomes. 

There is currently no evidence to suggest that the proportion of dietary energy from macronutrients (e.g. protein, carbohydrate and fat), otherwise known as macronutrient distribution, is different for people with active TB than for those without TB. It is generally recommended that all people consume approximately 15–30% of energy as protein, 25–35% as fat and 45–65% as carbohydrate. 

 

MICRONUTRIENTS- 

Micronutrient requirements in active TB

Low circulating concentrations of micronutrients, such as vitamins A, E and D, and the minerals iron, zinc and selenium have been reported from cohorts of patients beginning treatment for active TB. These usually return to normal after 2 months of appropriate TB treatment. Since studies have not been done on dietary intake near the time of diagnosis, it is unclear whether the low concentrations are related to low dietary intake, to metabolic processes or to the disease itself. It is unknown whether the observed return to normal concentrations is dependent on the quality of dietary intake