Pathogenesis of Infection of Mycobacterium Tuberculosis Bacterium Microbe

This essay explores the pathogenesis of infection of Mycobacterium tuberculosis bacterium microbe, including its virulence factors, symptoms in immunocompromised hosts, and methods of diagnosis and treatment.

ESSAY

TABLE OF CONTENTS
TOPIC..............................................................................................................................................1
INTRODUCTION...........................................................................................................................1
PATHOGENESIS OF INFECTION...............................................................................................1
CONCLUSION................................................................................................................................4
REREFENCES................................................................................................................................5

TOPIC
Pathogenesis of infection of Mycobacterium tuberculosis bacterium microbe
INTRODUCTION
Pathogenesis is a kind of process that involves many steps that majorly starts or begins
with transmission of infectious agent o microbe to host which further results in colonization of
the site which further results in invading into host system (Kriauciunas and et. al., 2019). there
are various kinds of microbes that that can invade into host system and develop colonies as a
result host system can suffer from different kinds of diseases due to colonization of microbes.
This essay will lay emphasis upon Pathogenesis of infection of bacterium microbe and
Tuberculosis disease which caused by Mycobacterium tuberculosis bacterium microbe. This
essay will also focus upon virulence factors of bacterium, symptoms suffered by
immunocompromised host when suffering from Tuberculosis and ways in which it can be treated
and diagnosed.
PATHOGENESIS OF INFECTION
Overview of bacterium and Tuberculosis diseases
Bacteria is a single microbe. Its cell structure is quite simpler than other organisms
Bacterium does not consist of any kind of membrane or nucleus bound organelles. In fact, their
control centre that contains genetic information is contained in a single loop of DNA. Some of
the bacteria also have an extra circle of genetic material which is called plasmid due to which
these bacterium gets an advantage over other bacteria (Gagneux, 2018). There are many different
kinds of bacterium such as acidobacteria, aquificae, firmicutes and many more. Each of these
bacterium causes different kinds of diseases. Tuberculosis is one of those disease which is
caused by a bacterium called Mycobacterium tuberculosis. This bacterium usually attacks at
lungs but it can attack at any part of body like kidney, spine, and brain. However, not eery host
attacked with Mycobacterium tuberculosis bacterium becomes sick. Some of the host can
become sick due to this bacterium and can suffer from tuberculosis whereas some of them might
not get sick.
Mycobacterium tuberculosis Bacterium a prokaryotic or eukaryotic type of microbe and its
implications in terms of treatment
There are two main types of microbes: prokaryotic or eukaryotic. Prokaryotic are type of
microbes in which nucleus is absent whereas, eukaryotic is a kind of microbe in which nucleus is
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present. Bacterium are prokaryotic single celled micro- organisms. Bacterium are normally
smaller than eukaryotic type of microbe (Zhang and et. al., 2017). Mycobacterium tuberculosis is
a species of pathogenic bacteria and is a caustic agent of tuberculosis. It has an unusual waxy
coating on its cell surface which is majorly because of presence of mycolic acid. Host who has
Mycobacterium tuberculosis suffer from tuberculosis. Most of the patient who suffer from
Mycobacterium tuberculosis are asymptomatic and can be eliminated subsequently in a
substantial proportion but when it becomes a bit complex it can develop tuberculosis disease. Or
treatment of TB mostly drug therapy is used which is given to patients for at least 6 to 8 months
depending upon seriousness of disease.
Bacterium’s preferred host is immunocompromised patients
An immunocompromised host is a patient who does not have ability to respond normally
to an infection and has a weak immune system. Mycobacterium tuberculosis bacterium mostly
preferred host is immunocompromised host. TB is most significant disease in such patients due
to which its frequency is high, morbidity and mortality is also high. Patients with HIV, diabetes
and other health related condition are immunocompromised host who can easily get infected
because of Mycobacterium tuberculosis (Huang, and et. al., 2018). For host especially patients
whose immune system is much weak, this bacterium is highly dangerous and can become a cause
of death. Its treatment is only effective if it is diagnosed and treated as soon as possible. This will
not only result in improving health condition of patients but will also help in preventing its
transmission to other patients.
Virulence factors of Bacterium
Virulence factors are molecules that are produced by bacteria or any other kinds of
microbe that can add to its effectiveness which further helps them or enable them in achieving
colonization of niche in the host that further results in causing a disease to host. For
Mycobacterium tuberculosis its virulence factors completely depend upon its ability to reside
within host cell and evade and evade the microbicidal mechanisms of macrophages. Outcome of
disease cause by this bacterium is highly variable. But still, Virulence factors of Mycobacterium
tuberculosis occurs during early steps of infection when bacilli encounter their host macrophages
(Sun, Champion and Bigi, 2019). There are approximately 250 genes that are involved in
metabolism of this bacterium and most of these lipids are important Virulence factors of bacteria
and within the mechanism by which they plays relevantly important role during infection or
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colonization. Other than this Phthiocerol dimycocerosate (PDIM) and phenolic glycolipids
(PGL) are included lipid cell walls, bounded to mycobacterial surface. Both PDIM and PGL are
important major virulence factors of this bacterium. This bacterium is an intracellular pathogen.
Mycobacterium tuberculosis is mostly transmitted to host body though an infected person in
airborne particles that are known as droplet nuclei. This transmission occurs when person inhales
droplet nuclei containing Mycobacterium tuberculosis traverse into host body. In similar manner
it can transfer from person to person.
Differences between the innate and adaptive immune systems and the protection afforded by
both
There are two important types of immune response systems: innate and adaptive systems.
Innate is the first line of defence against non-self-pathogens. Innate consist of physical, chemical
and cellular defences against pathogens. The main purpose of innate immune system is to
prevent spread and movement of foreign pathogens within host body. Whereas, adaptive immune
system is second line of defence against non-self-pathogens (Medina-Rodriguez, and et. al.,
2018). This immune system majorly focuses upon attacking non-self-pathogens but in many
times can make some errors and attack itself. For treatment of tuberculosis a combined effort of
both innate and adaptive immune systems is required. But when Mycobacterium tuberculosis
acquires cellular immune response then in such case response of immune system can be reduced
and its effectiveness in fighting with this bacterium also reduces that can result in development
of tuberculosis disease.
Symptoms suffered by host when suffering from Tuberculosis diseases and ways in which
Tuberculosis diseases is diagnosed and treated
First and the foremost symptoms of TB are productive cough and haemoptysis. However,
these symptoms might not be present within immunocompromised patients. Patient might also
suffer from non- specific symptoms as well such as chest pain, weight loss, lethargy and
recurrent fever (Xu and et. al., 2018). Immunocompromised patients can suffer from extreme
pain for few months from tuberculosis disease symptoms. If it is not treated or diagnosed at early
stages then it can result in some serious complications for bones, liver, kidney, heart and brain. If
early diagnosis and treatment is not done then it can cause some serious damage to body.
There are various kinds of diagnosis and test that can be done for early detection of
Mycobacterium tuberculosis bacterium that causes tuberculosis. Mantoux tuberculin skin test
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and tuberculosis blood test ate two most common types of test that are done for detection of
Mycobacterium tuberculosis bacterium infection. Diagnosis of TB is only done when patients
show symptoms like severe cough, chest pain and some times in severe cases haemoptysis as
well (Lange and et. al., 2018). When these symptoms are detected then in such case both
Mantoux tuberculin skin test and tuberculosis blood test are done so that this infection can be
detected in a timely manner. Skin test is measured in 48 to 72 hours (reaction on arm), whereas
blood test is done to measure immune system of patient and its reaction to Mycobacterium
tuberculosis bacterium. Bot the test re important to be done because many times skin test does
not show correct results. For this blood test is required to be done in order to confirm infection of
M. tuberculosis. In some cases chest x-ray is also done.
Treatment of tuberculosis requires different kinds od medicines. Patients who shou active
symptoms are required to undergo long term treatment that involve various kinds of medicines.
One of the most common medicines given to patients of tuberculosis are Isoniazid, Rifampin,
Ethambutol, and Pyrazinamide (Lange and et. al., 2018). Tuberculosis does have a vaccine
named Bacille Calmette-Guerin (BCG). This vaccine is mostly given to infants or small
children’s in countries where Tuberculosis is quite common. But this vaccine does not provide
complete protection to people from getting TB as this vaccine does not work well upon people
who are more then 35 years of age.
CONCLUSION
From the above essay it has been summarized that there are various kinds of microbes
that can invade within host body and work as an infectious agent. Mycobacterium tuberculosis
bacterium is a kind of microbe that mostly attacks at chest part of body. Due to this bacterium
host can suffer from tuberculosis whereas some of them might not get sick. Seriousness of
tuberculosis completely depends upon immune system of patients i.e. if their immune system is
strong then they might not get sick but if their immune system is not strong then they can
seriously get infected from this bacterium.
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REREFENCES
Books and Journals
Gagneux, S., 2018. Ecology and evolution of Mycobacterium tuberculosis. Nature Reviews
Microbiology. 16(4). p.202.
Huang, L., and et. al., 2018. Growth of Mycobacterium tuberculosis in vivo segregates with host
macrophage metabolism and ontogeny. Journal of Experimental Medicine. 215(4).
pp.1135-1152.
Kriauciunas, A., and et. al., 2019. The influence of Porphyromonas gingivalis bacterium causing
periodontal disease on the pathogenesis of rheumatoid arthritis: systematic review of
literature. Cureus. 11(5).
Lange, C., and et. al., 2018. Drug‐resistant tuberculosis: An update on disease burden, diagnosis
and treatment. Respirology. 23(7). pp.656-673.
Medina-Rodriguez, E.M., and et. al., 2018. Involvement of innate and adaptive immune systems
alterations in the pathophysiology and treatment of depression. Frontiers in
neuroscience. 12. p.547.
Sun, J., Champion, P.A. and Bigi, F., 2019. Cellular and Molecular Mechanisms of
Mycobacterium tuberculosis Virulence. Frontiers in cellular and infection
microbiology. 9.
Xu, K., and et. al., 2018. Nanomaterials in the prevention, diagnosis, and treatment of
Mycobacterium tuberculosis infections. Advanced healthcare materials. 7(1).
p.1700509.
Zhang, S., and et. al., 2017. Mycobacterium tuberculosis proteasome accessory factor a (PafA)
can transfer prokaryotic ubiquitin-like protein (pup) between substrates. MBio. 8(1).
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