Tuberculosis, also know simply as TB, is an infectious bacterial disease caused by Mycobacterium tuberculosis. Mycobacterium tuberculosis is characterized as a pathogenic non-motile rod-shaped bacterial species in the family Mycobacteriaceae. (Todar) With respect to the classic case of tuberculosis, MTB complexes are always found in the well-aerated upper lobes of the lungs because Mycobacterium tuberculosis is an obligate aerobe. (Todar) MTB is a facultative intracellular parasite that has a slow generation time of about 15-20 hours. This slow generation time is the physiological characteristic that contributes to its virulence.
MTB is not classified as either gram-positive or gram-negative because it does not possess the chemical characteristics of either, although the bacteria do contain peptidoglycan in their cell wall. (Todar) If a gram stain is performed on MTB, it will stain very weakly gram-positive or not stain at all. The cell wall structure of MTB is unique among prokaryotes and it is a key determinant of virulence for the bacterium. The cell wall complex contains peptidoglycan, but otherwise it is composed of complex lipids. (Todar) Over 60% of the mycobacterial cell wall is lipid. The lipid fraction of MTB's cell wall consists of three major components, mycolic acids, cord factor, and wax-D. Mycolic acids are unique alpha-branched lipids that make up 50% of the dry weight of the mycobacterial cell envelope. (Todar) They provide MTB with increased resistance to chemical damage and dehydration, and prevent the effective activity of hydrophobic antibiotics. In addition, the mycolic acids allow MTB to grow readily inside macrophages, effectively hiding it from the host's immune system. Cord Factor is responsible for ser...
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... upper respiratory infection, lung abscess, lung cancer, lymphoma, Mycobacterium avium, sarcoidosis, fungal infection, endocarditis, silicosis, asbestosis, and nocarditis.
In countries where tuberculosis is common, vaccination with the BCG vaccine is often recommended. For latent TB infection, an antibiotic called isoniazid (INH) is often prescribed to help prevent the dormant infection from becoming active. This medication needs to be taken for at least nine months to kill all of the latent Mycobacterium tuberculosis bacteria in the body. Active tuberculosis, particularly if it's a drug-resistant strain, will require several drugs at once. The most common medications used to treat tuberculosis include: Isoniazid, Rifampin (Rifadin, Rimactane), Ethambutol (Myambutol), and Pyrazinamide. Medication treatment for active TB disease can last as long as six to 12 months.
Mycobacterium is a bacillus –a rod shaped, cord forming, bacteria. The reason the organism creates problems for its host is due to the fact that its cell wall contains large wax like lipids called mycolic acids. Mycolic acids are strong hydrophobic molecules that form a lipid...
Isoniazid (also referred to as isonicotinic acid hydrazide or INH), one of the top two first-line drugs, is a powerful anti-TB drug that works by inhibiting the action of InhA, a crucial enzyme in the process of manufacturing the cell wall. In recent years however, there have emerged strains of TB that are increasingly resistant to Isoniazid. Instead of searching for new targets, there is a goal to expand on this already terrific target, and by doing so, find drugs that inhibit InhA, but do it by a different mechanism, thereby, showing efficacy against MDR-TB strains.
Tuberculosis or TB, referred to by some as the White death due to the epidemic that arose in Europe that lasted two hundred years, is usually caused by in humans by a microorganism by substrains of Mycobacterium tuberculosis. It’s hard to determine the exact years in which TB first infected humans, but since the disease leaves traces on the bone in can be found in archeological record and it is believed to go all the way back to the B.C. era. Although it is hard to tell if the bone damage was truly from TB, there is research that shows that it has been around since the 17th and 18th centuries with a high number of incidences of TB, and in 1882 Dr. Robert Koch announced that his discovery of the causing factor of TB, which is Mycobacterium tuberculosis. A tuberculosis bacterium is spread through the air by an infected person speaking, coughing, or sneezing. Due to the fact the bacteria is protected by a waxy cell all, the body’s defense takes weeks to develop any kind of immunity and it allows the bacteria to exponentially multiply freely within the body. If TB it’s left untreated it will eat rapidly through many tissues, usually beginning with the lungs, lymph nodes, and kidneys. As the infection spreads to the lungs, it causes a cough and fluid between the chest wall and lungs, which leads to chest pains, severe shortness of breath, and potential heart failure. TB also infects bones and joints that can produce arthritis like pain and characteristic bone damage. Another possibility is that it may affect the fluid around the brain, causing meningitis, which can lead to fever, drowsiness, and eventually coma and death (Wingerson, 2009).
...macrophage to kill bacteria that might have escaped from granuloma. Latent TB is characterized by absence of disease activity. It can be detected by TBT and Interferon-γ release assay (IGRA) and chest x-rays. The chest x-ray usually result normal due to the inactivity of the disease. TNF-α helps contain latent TB infection and keeps it from becoming active TB. Patient that have been treated withTNF antagonist are at greater risk of reactivation of LTBI to active TB
Tuberculosis is disease caused by a bacterium called Mycobacterium tuberculosis. Usually bacteria attacks lungs but TB bacteria can attack any parts of the body such as brain, kidney, and spine. It can spread through the lymph node and blood stream to any organ. Usually it is seen in the lungs. If it is not treated accordingly, it can be deadly. One of the leading causes of death in the United States was tuberculosis. Everyone who infected with TB bacteria not get sick. There are two TB conditions stand. They are latent TB infection and TB disease. In latent TB infection, people do not get sick but TB bacteria can live in you. People with latent TB infection cannot spread the bacteria to others nor are they infectious. If the bacteria is active and multiply, the person has TB disease. If a person has TB disease, their immune system cannot stop the bacteria become active. People with TB disease get sick and they are able to spread the bacteria to others.
Mycobacterium tuberculosis (M. tuberculosis) is the bacterium that causes the disease tuberculosis (TB). A distinctive characteristic of the genus Mycobacteria is the presence of a thick lipid-rich cell wall and resistance to the decolourization step of the gram stain (being acid-fast). The acid-fast characteristic of the M. tuberculosis is the result of a waxy, lipid-rich cell wall. The cell envelope of the tubercle bacilli contains a layer beyond the peptidoglycan which is exceptionally rich in lipids, glycolipids and polysaccharides. The bacterium is gram positive bacillus which is an obligate aerobe, is non-motile, a non-endospore forming and is non-capsulated. The microscopic appearance of M. tuberculosis is seen as straight, slightly curved rods approximately 3 x 0.3µm in size. In liquid culture media, the bacteria usually grow as twisted rope-like pellets known as ‘serpentine cords’. M. tuberculosis is capable of growing on a wide range of enriched culture media such as Lowenstein-Jensen medium or Middlebrook medium. The optimum growth temperature of the pathogenic organsim is 35-37°C and unlike most other mycobacteria, it cannot grow at a temperature of 25°C or 41°C. M. tuberculosis is an airborne pathogen that is transmitted from person to person, usually infecting the respiratory tract through inhalation (Greenwood, et al., 2012).
The name Tuberculosis derives from ‘tubercles’, which are present in the lymph nodes of affected animals.
Mycobacterium tuberculosis (MTB) is the main causative organism which attacks the lungs but can also infect other organs of the body. M.tuberculosis is an intracellular pathogen that is highly adapted to human.7The bacterium spread primarily through aerosolized infectious particles generated from coughing and sneezing by individuals with pulmonary tuberculosis and less commonly via skin wounds 8. The most important factors influencing the current TB epidemic in resource poor setting are closely related to malnutrition, overcrowded living conditions and lack of access to free or affordable health care services.9
Mycobacterium tuberculosis (MT) is a slender, rod-shaped, aerobic bacillus which causes tuberculosis. Tuberculosis (TB) is an airborn infection which is transmitted via inhaling droplet nuclei circulating in the air. These droplets are expelled from the respiratory secretion of people who have active TB through coughing, sneezing, and talking (Porth, 2011). Some bacilli stay in the upper airway and are swept out by mucus-secreting goblet cells and cilia on the surface of the airway. Others will escape from this protective mechanism to travel and settle down at alveoli (Porth, 2011). Local inflammatory reaction occurs and macrophages are cells that act as next line defense mechanism to fight with mycobacteria. First they engulf micobacteria, try to reduce their strength and ability, and kill them. In the same way they send antigen to helper T lymphocytes to initiate a cell-mediated immune response (Knechel, 2009). The infected macrophages will send produced cytokines and enzymes to breakdown mycobacteria’s protein. It is the released cytokines that attract T ly...
"Chapter 6 Treatment of Tuberculosis Disease." . Centers for Disease Control and Prevention, n.d. Web. 13 May 2014. .
Tuberculosis (TB) is an infection that affects the lungs caused by an acid-fast bacillus M. tuberculosis (McCance, Huether, Brashers, & Rote, 2010, p. 1293). It is also considered as the leading cause of death from a curable infectious disease worldwide. It is highly contagious and the mode of transmission is by airborne droplets. A person can be exposed to the infection but not develop the illness, which is called latent TB infection. Unless the person is immunocompromised, some people remain asymptomatic until the disease is advanced. Signs and symptoms of TB includes fatigue, weight loss, lethargy, anorexia, and low grade fever that occurs in the afternoon. Diagnosis of the disease can be made through positive tuberculin skin test, sputum culture, immunoassays, and chest radiographs.
Most types of mycobacteria develop a rope like structured bacteria. Types in its Mycobacterium tuberculosis have a genetically configured to specially to transmit a disease to human. Mycobacterium tuberculosis most commonly attacks the lungs, but tuberculosis germs can infect any body part. Mycobacterium tuberculosis is a pathogenic bacterial form of species within the family of Mycobacteriaceae. Tuberculosis can be found mostly in Africa and Southern Asia this is because they are a poor and undeveloped country.
Mycobacterium tuberculosis is a nonmotile, acid-fast, obligate aerobe. The bacilli are 2-4 um in length and have a very slow generation time of between 15 and 20 hours. The cell wall of the mycobacterium is unique in that it is composed mainly of acidic waxes, specifically mycolic acids. M. tuberculosis is unusually resistant to drying and chemicals, contributing to the ease with which it is transmitted.
The disease can be caused by different mycobacterium such as Mycobacterium bovis, M. africanum, M. canettii, M. microti, and most commonly, M. tuberculosis; although the five are highly similar and are together termed the Mycobacterium tuberculosis complex (MTBC). Recently, two additional organisms. Mycobacterium pinnipedii and Mycobacterium caprae have also been implicated with the disease in humans. 6, 7 Members of the MTBC are gram-positive, long, rod-shaped bacterium with unique characteristics such as an exceptionally slow growth rate and a high content of lipids in their cell wall which provide protection against degradation and may account for their persistent survival in the environment even after the death of a host. 8
Tuberculosis has plagued mankind for a long time. This disease, which was previously believed to be eradicated, has once again shown up and begun attacking the lives of many humans. Tuberculosis infects a third of the population and kills a fraction of them. Many approaches have been used including different varieties of infection control, bodily defenses, and treatments to try to protect humans from tuberculosis. The best way to prevent tuberculosis infections is to contain the source of tuberculosis. The most common source of tuberculosis infection is from infected humans. By diagnosing, containing, and treating people with latent tuberculosis before they get active, contagious tuberculosis, tuberculosis can be quickly contained. Once someone has been diagnosed with TB, they should be placed under isolation.