Tuberculosis
Tuberculosis is caused by Mycobacterium tuberculosis (M.TB.), has a unique cell wall, making it difficult to kill and stain. Three matjor components compose the cell wall: mycolic acids, cord factor, and Wax-D. M.TB. is also hard to culture and can only thrive in the body. It is an obligate aerobe and an acid-fast bacteria. Tuberculosis can be diagnosed through the Mantoux test and by staining methods such as the Ziel-Neelsen method. Chest x-rays are also used in the diagnosis process to detect any damage done to the lungs.
Tuberculosis is caused by M.TB. This bacterium is hard to kill because of its cell wall, which is 60% lipid. M.TB. is also difficult to stain and culture (Todar, Kenneth paragraoh 14). Skin tests and microbiologic smears and cultures are the main methods used to diagnose TB, though the full diagnosis consists of many more tests.
M.TB. is a rod-shaped bacterium related to the Actinomycetes. The rods are 2 to 4 um long and 0.2 to 0.5 um wide. This bacterium is an obligate aerobe, an organism that needs oxygen to survive. It is a tough bacterium that can withstand weak disinfectants and can survive in a dry state for weeks. M. TB. is a slow-growing bacterium that divides every 16 to 20 hours, which is extremely slow compared to other bacterium, which have division times measured in minutes (Wikipedia paragraph 1). Although M.TB. contains peptidoglycan in their cell wall, it is neither Gram-positive nor Gram-negative because it lacks the chemical characteristics of either. The Mycobacterium species is classified as acid-fast bacteria because it is virtually impermeable to certain dyes and stains, but once stained, the dye is permanent. The Ziehl-Neelsen method is one method used to stain Mycobac...
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...ed as an acid-fast bacilli because of its impermeability to stains. The Mantoux skin test, Ziel-Neelsen method, BACTEC system, and the chest x-rays make up the most common methods used to diagnose tuberculosis. Although M.TB. is difficult study under a microscope, the understanding of the cell wall structure helps scientists to invent treatments for tuberculosis.
“Tuberculosis.” Todar, Kenneth. Todar’s Online Textbook of Bacteriology.
2006 University of Wisconsin-Madison, Department of Bacteriology.
2007 23 July 2006
http://www.textbookofbacteriology.net/tuberculosis.htm
“Tuberculosis.” Wikipedia. 27 July 2006 Wikipedia Foundation, Inc. 22 July 2006
http://en.wikipedia.org/wiki/Tuberculosis
“Tuberculosis.” University of Michigan Health System. 14 March 2005 University of Michigan Health System. 22 July 2006
http://www.med.umich.edu/1libr/aha/aha_tb_crs.htm
They can be found anywhere and identifying them becomes crucial to understanding their characteristics and their effects on other living things, especially humans. Biochemical testing helps us identify the microorganism present with great accuracy. The tests used in this experiment are rudimentary but are fundamental starting points for tests used in medical labs and helps students attain a better understanding of how tests are conducted in a real lab setting. The first step in this process is to use gram-staining technique to narrow down the unknown bacteria into one of the two big domains; gram-negative and gram-positive. Once the gram type is identified, biochemical tests are conducted to narrow down the specific bacterial species.
The results of the gram stain test were cocci and purple. This indicated that the unknown bacteria were gram positive. The gram stain test eliminated Escherichia coli, Klebsiella pneumonia, Salmonella enterica, and Yersinia enterocolitica as choices because these bacteria are gram negative. Next a Blood Agar plate was used because in order to do a MSA or a Catalase test there needs to be a colony of the bacteria. The result of the Blood Agar plate was nonhemolytic.
Paul Farmer designed several studies that he used to help create new TB treatment methods, including a study about a system called active case finding, which helps find TB cases more quickly. The previous system of tuberculosis case finding is known as passive case finding. Passive case finding is when tu...
The Gram stain is a system used to characterize bacteria based on the structural characteristics of their cell walls. A Gram-positive cell will stain purple if cell walls are thick and a Gram-negative cell wall appears pink. Most bacteria can be classified as belonging to one of four groups (Gram-positive cocci, Gram-positive bacilli, Gram-negative cocci, and Gram-negative bacilli) (Phenotypic analysis. (n.d.).
Signs and Symptoms of Active Tuberculosis 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.
Hepatitis is the inflammation or swelling of the liver. The inflammation can happen from different injuries or viral forms of a disease. People who experience hepatitis have the symptoms of malaise, nausea, vomiting, loss of appetite, fever and jaundice. There are six known forms of Hepatitis which are Hepatitis A, Hepatitis B, Hepatitis C, Hepatitis D, Hepatitis E and Hepatitis G. The presence of hepatitis in the body can be very risky and cause severe death if not taken care of. Hepatitis is a severe issue that affect many people around the world like third world countries and cross contamination can occur mainly in health care places due to the exposure of patients with the disease and accidents handling blood or instruments, Hepatitis A,B,C,D,E and G are distinct diseases that differ in transmission and vaccines to prevent them or cure them.
One of the first steps to treating Tuberculosis is identifying which form has developed in the body. The two forms that could progress in the body are latent Tuberculosis infection and active Tuberculosis infection (CDC, Morbidity and Mortality Weekly Reports). Latent Tuberculosis is the dormant form of the bacteria, meaning that it is inactive and doesn?t cause an infectious reaction in the body. Even if the latent form enters the body, treatment should be sought (CDC, Morbidity and Mortality Weekly Reports). Latent Tuberculosis can become active Tuberculosis easily though, especially if the immune system is compromised by another infection, like HIV (CDC, Morbidity and Mortality Weekly Reports). Active Tuberculosis infects the body immediately. Symptoms show in the body meaning the bacteria is effecting the cells of the body. Identifying the form is important because treatment is dependent upon it. Testing for TB involves a skin test, usually within seven work-days of contact with the bacteria. Without knowing what is in the body, the drugs won?t be as effective and might even cause drug-resistance.
TB can attack any part of the system. The lungs are the most common area of
Tuberculosis is transmitted from person to person through airborne droplets, when a person that is infected with TB coughs, sneezes, talks, and/or sings letting tiny droplet to be released into the air(Bare, Smeltzer, Hinkle, and Cheever, 2008). TB cannot be spread through touching inanimate objects, food, or drinks (Bare et al. 2008). The person must be in the same area an affected individual is in and inspirate the droplets to be affected. Once the bacillus is inspired into the lungs, the bacilli start to multiply causing lung inflammation also known as nonspecific pneumontis (Huether et al. 2008). To cause an immune response the bacilli will travel through lymphatic system and become lodged in the lymph nodes (Huether et al. 2008). Lung inflammation causes the activation of the alveolar macrophages and neutrophils (Huether et al. 2008). Granulomas, new tissue masses of live and dead bacilli, are surrounded by macrophages, which form a protective wall. They then transform into a fibrous tissue mass, the central portion is called a ghon tubercle (Bare et al. 2008). The bacterial then necrotic, forming a cheesy mass, this mass may become calcified and form a collagenous scar (Bare et al. 2008). At this point, the bacteria becomes dormant and there is no further progression of the active disease. The disease can become active again by re-infection or activation of the dormant bacteria (Bare et al. 2008).
Tuberculosis is an air-borne disease, hence, it can be passed from an infected person to a healthy individual through coughing, sneezing and other salivary secretions. Tuberculosis is caused by the transfer of Mycobacteriun Tuberculosis (M. Tuberculosis) also known as Tubercle Bacillus, a small particle of 1-5 microns in diameter, due to the small size, when an infected person sneezes or coughs, about 3,000 particles are expelled. M. Tuberculosis responsible for tuberculosis is able to stay in the air for a long period of time (about 6hoursAnother way of acquiring Tuberculosis is by drinking unpasteurized milk, milk straight from cow, although this is not a common mode of transmission, it can be found in rural areas. Ingestion of contaminated cow milk transmits Mycobacterium Bovis, the animal form which is still potent enough to cause tuberculosis in humans. ). Tuberculosis transmission is affected by exposure, socioeconomic status of person, proximity, immune status of uninfected individual (%&&%&? CDC).
Malaria (also called biduoterian fever, blackwater fever, falciparum malaria, plasmodium, Quartan malaria, and tertian malaria) is one of the most infectious and most common diseases in the world. This serious, sometimes-fatal disease is caused by a parasite that is carried by a certain species of mosquito called the Anopheles. It claims more lives every year than any other transmissible disease except tuberculosis. Every year, five hundred million adults and children (around nine percent of the world’s population) contract the disease and of these, one hundred million people die. Children are more susceptible to the disease than adults, and in Africa, where ninety percent of the world’s cases occur and where eighty percent of the cases are treated at home, one in twenty children die of the disease before they reach the age of five. Pregnant women are also more vulnerable to disease and in certain parts of Africa, they are four times as likely to contract the disease and only half as likely to survive it.
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.
Wines, M. 2007. Virulent TB in South Africa may imperil millions. New York Time. January 8. Accessed online at http://www.nytimes.com/2007/01/28/world/africa/28tuberculosis.html?pagewanted=all
Its history is long and successful. Additionally, its sensitivity and simplicity, spatial and temporal resolution have all played a part in its importance that has led to its persistence as the gold standard in disease detection (Kiernan, 1999; Boekelheide, K. & Schuppe-Koistinen, I. 2012)
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