Download 11 Gram Positive flashcards

Gram Positive Bacteria
1. What do INVASINS do?
2. What are ADHESINS?
3. What are Enterotoxins?
4. What is an Endotoxin?
5. What is a Lipopolysaccharide
(LPS)?
6. What is Lipid A?
7. What is an Exotoxin?
8. What does Hemolysin cause?
9. What do Neurotoxins do?
10. What does H Ag stand for?
11. What is K Ag?
12. What is O Ag?
13. What do capsules do for bacteria?
14. How does motility help bacteria?
15. Define Angiotropic.
16. What does β lactamase block?
17. What are MDR plasmids?
18. What are facultative intracellular
pathogens?
19. What is Ribosylase?
20. What does Coagulase do?
They activate the host cell's cytoskeletal machinery enabling
bacterial entry into the cell so it can get nutrients and be
protected from complement (the host’s way of popping the
bacterial cell membrane), antibodies, and other body defenses.
They are surface proteins found in the cell wall of
various bacteria to enable them to bind to specific receptor
molecules on the surface of host.
Enterotoxin: acts on the intestinal wall (causes GI upset)
They tend to be produced by Gram-positive bacteria rather
than by Gram-negative bacteria. There are exceptions, such as
Vibrio cholerae.
Endotoxin: Pieces of the bacterium which are toxic to
humans
Lipopolysaccharide (LPS): a protein in the cell wall of many
Gram negative organisms. It is detected as foreign (an
antigen) and launches an immune response.
Lipid A: A portion of the lipopolysaccharide which is also an
antigen
Exotoxin: produced by a bacterium and then released from
the cell into the surrounding environment. The damage caused
by an exotoxin can only occur upon release.
Hemolysins: cause rupture of red blood cells
Neurotoxin: disrupts nerve cells.
The H antigen (H Ag) is a flagella on bacteria
K Ag: an antigenetic protein on the capsule of bacteria
O Ag: a string of sugars on the lipopolysaccharide (LPS) in
bacterial cell walls.
Capsule: Helps prevent phagocytosis
Motility: Helps to spread disease within host
Angiotrophic: Means the organism has the ability to cause
blood vessels to grow towards it to feed it.
β lactamase: an enzyme produced by some bacteria that
blocks the ability of certain antibiotics (penicillin) to destroy
the bacteria
MDR plasmids (genes that provide tetracycline resistance)
Facultative intracellular pathogens: are capable of transient
survival even in phagocytes that exert oxidative / nonoxidative mechanisms
Ribosylase: an enzyme produced by some bacteria that
modifies host’s proteins, causing massive fluid secretion from
the lining of the lumen (in intestines causes diarrhea, in
trachea causes coughing). Seen in cholera toxin, diphtheria
toxin, and pertussis toxin.
Coagulase: enzyme produced by some bacteria that causes
tiny blood clots so bacteria can hide from WBC’s
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Gram Positive Bacteria
21. What does IgA or IgG protease
do?
22. What does PG (prostaglandin
cause?
IgA or IgG protease: enzyme produced by some bacteria
that prevents agglutination by antibodies
PG (prostaglandins): The immune response causes the host
to release PG to fight the infection but the side effects are
fever (pyrogenic) and inflammation.
23. What does hyaluronidase do?
Hyaluronidase: an enzyme produced by some bacteria that
dissolves fluid between cells so bacteria can spread faster
between tissue planes
24. What does SOD (superoxide
-SOD (superoxide dismutase): an enzyme produced by some
bacteria that deactivates contents of lysosomes
dismutase) do?
25. What does Staphylokinase do?
-Staphylokinase: an enzyme produced by some bacteria that
digests clots so bacteria can spread
26. Is Staphylococcus normal flora?
Yes; that means it is part of every human’s microbiota, and
can be opportunistic pathogens if the skin is broken
27. Difference between staphylococcus -Catalase present
from Streptococcus?
-Has SOD, which is anti-phagocytic by converting
Staphylococcus has…..
H2O2  H2O  O2
-That allows them to survive within eukaryotic phagocytic
cells (neutrophils/macrophages)
28. Structure and physiology of
- Gram-positive cocci, non-motile, facultative anaerobes
staphylococcus
-Cells occur in grapelike clusters because cells division occurs
along different planes and the daughter cells remain attached
to one another
-Salt-tolerant-allows them to tolerate the salt present on
human skin
-Tolerant of desiccation (drying)-allows survival on
environmental surfaces (fomites)
29. Four species of Staphylococcus
S. aureus
that cause disease in humans
S. haemolyticus (axillae, perineum, and ingunial areas)
S. epidermidis
S. saprophyticus
30. How else does S. aureus interfere
Inhibit chemotaxis of WBC’s
with white blood cells (WBCs)?
Having Protein A on its cell surface inhibits phagocytosis by
WBC’s
31. How does S. aureus interfere with Binds the hypervariable region of IgG antibodies
antibody attacks?
Having Protein A on its cell surface inhibits the complement
cascade (part of immune response which pops the bacterial
cell membrane)
32. How does a slime layer provide
Facilitates attachment of Staphylococcus to artificial surfaces
defense against Phagocytosis?
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Gram Positive Bacteria
33.
34. How does S. aureus interfere with
the action of platelets?
35. How does S. aureus spread in the
body?
36. How does S. aureus survive on the
skin surface?
37. What does S. aureus use the
enzyme DNase for?
38. What does S. aureus use the
enzyme β-lactamase for?
39. Which Gram positive bacteria
produce more toxins than other
species?
40. What are Hemolysins?
By producing coagulase, an enzyme that makes tiny blood
clots to allow the bacteria to hide from phagocytic cells.
It also produces Fibrinolysis, allowing it to free itself from
clots when it wants to spread.
By producing Hyaluronidase to break down hyaluronic acid,
enabling the bacteria to spread between cells. Hyaluronic acid
is a fluid between body cells, and is also found in joints.
By producing the enzyme lipase, which digests lipids,
allowing staphylococcus to grow on the skin’s surface and in
cutaneous oil glands
Reduces viscosity in abscesses
Breaks down penicillin and other β -lactam antimicrobial
drugs
Staphylococcus aureus
Enzymes produced by some bacteria that breaks down red
blood cells so bacteria can ingest the nutrients
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Gram Positive Bacteria
41. What are 3 types of hemolysis?
 (alpha hemolysis). The red blood cell is only partially
destroyed. Shows up as a green color on a blood agar plate
 (Beta hymolysis). The red blood cell is completely
destroyed. Shows up as a clear area on blood agar plate.
Streptococcus (strep throat) is one organism that does this.
 (gamma hemolysis). RBC is not destroyed. No color change
42. What are enterotoxins?
43. Staphylococcal Diseases – What
are the 3 categories?
44. What are the characteristics of
noninvasive disease?
45. What are the symptoms of staph
food poisoning?
46. What are the characteristics of
cutaneous staphylococcal disease?
47. What is Toxic shock syndromeTSS?
48. What is Bacteremia
49. What is Endocarditis
50. What is Pneumonia
51. What is Osteomyelitis
52. How do you determine if
Staphylococcus species is S.
aureus?
53. If a Staphylococcus is catalase
negative, how do you determine if
the species is epidermidis or
saprophyticus?
54. What are the characteristics of S.
epidermidis?
55. What is quorum-sensing?
on blood agar plate.
Stimulate the intestinal muscle contractions, nausea, and
intense vomiting associated with staphylococcal food
poisoning
Noninvasive Disease, Cutaneous Disease, Systemic Disease
Food poisoning from the ingestion of enterotoxincontaminated food
nausea, vomiting, retching, stomach cramping, and diarrhea.
In more severe cases, dehydration, headache, muscle
cramping, and changes in blood pressure and pulse rate may
occur.
Various skin conditions including scalded skin syndrome,
impetigo, folliculitis, and furuncles (boils)
toxin is absorbed into the blood and causes shock that is life
threatening
presence of bacteria in the blood
occurs when bacteria attack the lining of the heart
inflammation of the lungs in which the alveoli and
bronchioles become filled with fluid
Infection of bone
S. aureus is catalase positive
S. epidermidis: Novobiocin-sensitive
S. saprophyticus: Novobiocin-resistant
-Coagulase-negative
-Produces a biofilm that allows adherence to prosthetic
devices. People with artificial joints need prophylactic
antibiotics before other surgeries for this reason.
- Quorum-sensing
Ability to coordinate gene expression according to the density
of their local population. They will wait until there are many
bacteria nearby, and then they will all start at the same time to
express genes for proteins to help with the invasion. This
coordinated invasion overwhelms the host defenses.
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Gram Positive Bacteria
56. What drug is used to treat
Methicillin
staphylococcal infections?
57. What is Methicillin?
58. What does MRSA stand for?
59. Where do many MRSA infections
occur?
60. The type of MRSA with a higher
Is a semisynthetic form of penicillin and is not inactivated by
b-lactamase
Methicillin resistant Staphylococcus aureus
in hospitals and healthcare facilities
Healthcare acquired MRSA or HA-MRSA
incidence rate in nursing homes or
long-term care facilities is known as
what?
61. What is becoming increasingly
difficult to treat?
62. How do you prevent infection by
S. epidermidis?
63. What is the structure of
streptococcus?
64. How are streptococci classified?
65. What is the Lancefield
classification entail?
66. What is the Lancefield Group A
pathogen?
67. What is the Lancefield Group B
pathogen?
68. Do pathogenic strains of
Streptococcus pyogenes form a
capsule?
69. What is pharyngitis?
70. Where does scarlet-fever rash
begin and where does it spread to?
71. What is pyoderma?
72. What is streptococcal toxic shock
syndrome?
73. What do pyrogenic toxins do?
74. What 3 types of cells do
streptolysins lyse?
Serious MRSA infections, especially HA-MRSA infections
-Hand antisepsis is the most important measure in preventing
nosocomial infections (wash hands after patient contact)
- proper cleansing of wounds and surgical openings
- aseptic use of catheters or indwelling needles
- appropriate use of antiseptics
Gram-positive cocci, arranged in pairs or chains, that are
facultative anaerobes
The Lancefield classification
-Divides the streptococci into serotype groups based on the
bacteria’s antigens (M proteins)
- Human streptococcal pathogens are in Lancefield groups A
and B
Streptococcus pyogenes (strep throat)
Streptococcus agalactiae (normal GI flora in adults, but is the
major cause of septicemia in newborns)
YES
Inflammation of the pharynx
Begins on the chest and spreads to the rest of the body
Confined, pus-producing lesion that usually occurs on the
face, arms, or legs
Bacteremia and severe multisystem infection
Stimulate macrophages and helper T cells to release
cytokines, which call other WBCs to the infection site
1) White blood cells
2) Red blood cells
3) Platelets
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Gram Positive Bacteria
75. What does Protein M do to help
Group A streptococci?
76. What is Necrotizing fasciitis?
77. What are the early signs and
symptoms of necrotizing fasciitis?
78. What is Rheumatic fever?
79. What is Mortality of Streptococcal
Toxic Shock Syndrome (STSS)
80. What are the early signs and
symptoms of STSS?
81. Diagnosis of Streptococcal Toxic
Shock Syndrome (STSS)
82. Treatment of Streptococcal Toxic
Shock Syndrome (STSS)
83. Prevention of Streptococcal Toxic
Shock Syndrome (STSS)
84. GROUP B STREPTOCOCCUS
85. What is the leading infectious
cause of neonatal sepsis in U.S.?
86. Where dose GBS usually live?
87. What are the risk factors for earlyonset GBS disease?
88. What are the prevention of earlyonset GBS disease?
Protein M helps to camouflage them from WBCs
Bacterial infection that destroys muscle and fat tissue and
quickly spreads between tissue planes
severe pain and swelling. often rapidly increasing, fever,
redness at a wound site
Streptococcal infection that has entered the bloodstream and
can lead to scarring of heart valves
35%
fever
abrupt onset of generalized or localized severe pain, often in
one arm or leg
Dizziness
Influenza-like syndrome
A flat red rash over large areas of the body (only occurs in
10% of cases)
Observation of Gram-positive bacteria in short chains or pairs
or immunological tests that identify the presence of group A
streptococcal antigens
Streptococci are normally in the pharynx so their presence in
a respiratory sample is of little diagnostic value
Cephalosporin (third generation penicillin) is very effective
Antibodies against M protein provide long-term protection
against future infection of S. pyogenes, but only if it is the
same strain
Gram positive, beta hemolytic bacteria
Common colonizer of human gastrointestinal and
genitourinary tracts
Causes serious disease in young infants, pregnant women and
older adults
The most common cause of sepsis and meningitis in infants
<3 months
Group B Streptococcus (GBS) Disease
 In gastrointestinal tract but can spread to the genital tract.
 Obstetric risk factors
 GBS in the mother’s urine during pregnancy (marker for
heavy colonization).
 Previous infant with GBS disease
 Low maternal levels of anti-GBS antibodies
 Intrapartum antibiotics (IAP)
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Gram Positive Bacteria
89. Intrapartum antibiotics (IAP)
90. Alpha-Hemolytic Streptococci
91. What organism produces alpha
hemolysis?
92. What organism normally colonizes
the mouths and pharynx but can
cause disease if travels to the lungs
93. What is pneumolysin?
94. What to diseases are caused by
bacteria invading the sinuses or middle
ear, often following a viral infection
95. How do you diagnose
Streptococcus pneumoniae?
96. What would be treatment for
Streptococcus pneumoniae?
97. How can you prevent
Streptococcus pneumoniae?
98. Previously classified as group D
streptococci but differed enough to be
reclassified as a separate genus
99. Form short chains and pairs and
lack a capsule
100. Found in the human colon but are
rarely pathogenic at this site
101. Can cause disease if they are
introduced into other parts of the body,
such as the urinary tract or bloodstream
102. What types of infections may be
caused by Enterococcus?
103. Why is treatment for
Enterococcus difficult?
104. Why is prevention for
Enterococcus difficult?
 Highly effective at preventing early-onset disease in
women at risk of transmitting GBS to their newborns.
 Efficacy in clinical trials: 100%.

 Produce a green pigment when grown on blood agar.
 Normally inhabit the mouth, pharynx, GI tract, genital
tract, and urinary tract.
 One of the causes of dental caries and dental plaques.
 If enter the blood can cause meningitis and endocarditis.
Streptococcus pneumoniae
Streptococcus pneumoniae
Enzyme produced by some bacteria which lyses epithelial
cells in the lungs
Sinusitis (sinus infection) and otitis media (middle ear
infection)
Gram strain of sputum smears, then Quelling reaction (anticapsular antibodies cause the capsule to swell), confirming the
presence of bacteria
Cephalosporin
Vaccine made from purified capsular material. Provides long
lasting immunity in normal adults but is not as effective in
children, the elderly, or AIDS patients
Enterococcus
Enterococcus
Enterococcus
Enterococcus
An important cause of nosocomial infections
Treatment is difficult because enterococci are often resistant
to antimicrobials
Prevention is difficult, especially in a health care setting,
where patients’ often have weakened immune systems
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Gram Positive Bacteria
105. Describe Bacillus
106. What is the rapid-onset emetic
syndrome of B. cereus?
107. When does vomiting occur
108. What is the slow-onset diarrheal
syndrome of B. cereus?
109. What are treatments for
symptoms caused by B. cereus?
110. What are the 3 ways humans can
contract Bacillus Anthracis
111. What disease does Bacillus
Anthracis cause?
112. What three clinical manifestations
can Anthrax have?
113. What are the signs and symptoms
of GI Anthrax?
114. Signs and symptoms of
Cutaneous Anthrax
115. Signs and symptoms of Inhalation
Anthrax
116. Symptoms of advanced Inhalation
Anthrax
117. How does Inhalation Anthrax
infect?
118. Diagnosis of anthrax
•
Gram-positive bacilli, that occurs singly, in pairs, or in
chains
• Forms endospores
• Typically motile
Rapid-onset emetic syndrome
Causes nausea and vomiting
Begins one to five hours after contaminated food is eaten.
Diarrhea
Abdominal pain occurs 8 to 16 hours after consumption of
contaminated food.
Oral hydration
IV fluid
1. Inhalation of spores
2. Inoculation of spores into the body through a break in
the skin
3. Ingestion of spores
Anthrax
Gastrointestinal, cutaneous, and inhalation anthrax
-
Rare in humans
Stomach pain
Loss of appetite
Bloody diarrhea
Nausea
Fever
Vomiting blood
o Intestinal hemorrhaging and eventually death
in 60% of cases
Produces a black scabby ulcer called an eschar as well as
toxemia (toxins in the blood)
- Similar to GI Anthrax
- Fever
- Nausea
- Vomiting
- Aches
- Fatigue
- Labored breathing
- Shock
- Death
Rare in humans
Spores germinate in the lungs and secrete toxins that are
absorbed into the bloodstream
Mortality rate of 75%
Presence of large, nonmotile, gram- positive bacilli in clinical
samples of the lungs or skin
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Gram Positive Bacteria
119. What is the treatment for anthrax?
120. What are 2 methods of
prevention?
121. What is Clostridium?
122. Where is it found?
123. Does the presence of endospores
allow for survival in harsh conditions?
124. Where does Clostridium
perfringens grow?
125. What does C. perfringens
produce?
126. What 2 diseases does C.
perfringens cause?
127. What is food poisoning
characterized by?
128. How are C. perfringens
endospores introduced into the body in
the case of gas gangrene?
129. What do the endospores cause
once they begin to germinate?
130. What indicates the involvement of
Clostridium in food poisoning?
131. What is the treatment for most
cases of food poisoning?
132. What is the treatment for gas
gangrene?
133. How does one prevent infection
by Clostridium perfringens?
134. What is Clostridium difficile?
135. What are the signs and symptoms
of Clostridium difficile?
136. How is Clostridium difficile
diagnosed and treated?
Ciprofloxacin and many other antimicrobials are effective
against B. anthracis
Control the disease in animals
Anthrax vaccine – available but requires multiple doses and
boosters
Gram-positive, anaerobic, endospore-forming bacillus
Ubiquitous in soil, water, and the gastrointestinal tracts of
animals and humans
Yes
Commonly grows in the digestive tracts of animals and
humans
11 toxins that have various effects on the body and can result
in irreversible damage
1) food poisoning
2)gas gangrene
Abdominal cramps and watery diarrhea
Through some traumatic event.
They cause necrosis that is often accompanied by foul
smelling gaseous bacterial waste products.
The presence of more than 10-5 bacteria in a gram of food or
10-6 cells per gram of feces.
-Gas gangrene is usually a diagnostic by itself
Ride it out; drink lots of water, eat only grains (toast) or
sugars (7-Up), replace electrolytes (Pedialyte)
Remove the dead tissue and administer large doses of
Cephalosporin.
Proper cleaning of wounds, otherwise fairly difficult to
prevent because it is so common.
Common member of the intestinal microbiota
Opportunistic pathogen in patients treated with broadspectrum antimicrobial drugs
Minor infections can result in a self-limiting explosive
diarrhea
Serious cases can cause pseudomonas colitis
Can result in perforation of the colon, leading to massive
internal infection by fecal bacteria and eventual death
Diagnosed by isolating the organism from feces or by
demonstrating the presence of toxins via immunoassay
Minor infections are usually resolved by discontinuing use of
the antimicrobial drug in use
Serious cases are treated with antibiotics
Proper hygiene is critical for limiting nosocomial infections
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Gram Positive Bacteria
137. What is Clostridium botulinum?
Anaerobic, endospore-forming, Gram-positive bacillus
Common in soil and water
Botulism results when the endopsores germinate and produce
botulism toxin
The different botulism toxins are the deadliest toxins known
138. What is botulism?
Botulism is not an infection, but an intoxification caused by
the botulism toxin
139. What are the 3 forms of botulism? Food-borne botulism
Infant botulism
Wound botulism
140. Describe Food borne botulism
Consumption of toxin in home-canned foods or preserved fish
or dented cans of food. Can result in a progressive paralysis
that results in death due to the inability to inhale
141. What is the outcome of food
Can result in a progressive paralysis that results in death due
borne botulism?
to the inability to inhale
142. What is infant botulism?
Results from the ingestion of endospores, which germinate,
and colonize the gastrointestinal tract due to the lack of
sufficient numbers of normal microbiota
143. What are the symptoms of infant
Symptoms include constipation and “failure to thrive”, but
botulism?
paralysis and death are rare
144. What food is infant botulism
It is associated with eating honey. Infants less than 1 year old
associated with?
should never eat honey. They do not have enough normal GI
microbes to outcompete Clostridium spores that are in honey.
145. What are the characteristics of
 Wound becomes contaminated with endospores
wound botulism?
 Symptoms are the same as with food-borne botulism
146. What is the diagnosis for
 Symptoms of botulism are diagnostic
botulism?
 Confirm diagnosis by culturing the organism from
food, feces, or the patient’s wound
147. What are the (3) approaches to the
1. Repeated washing of the intestinal tract to remove
treatment of botulism?
Clostridium
2. Administer antibodies against botulism toxin to
neutralize toxin in the blood
3. Administer antimicrobials drugs to kill clostridia in
infant botulism cases
148. What are the preventions of
 Proper canning of food to prevent contamination
botulism?
 Don’t buy dented cans of food
 Infants should not consume honey under the age of 1
149. What is clostridium tetani?
Also known as tetanus: Endospore-forming, obligately
anaerobic, Gram-positive rods
150. Where is clostridium tetani
Ubiquitous in soil, dust, and the GI tract of animals and
found?
humans
151. How does tetanus occur?
 Tetanus results when the bacterial endopsores
germinate and produce tetanus toxin
 Tetanus results in spasms and contractions that can
result in death because patients can’t exhale
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Gram Positive Bacteria
152. What does tetanus toxin (TeNT)
bind to?
153. After TeNT binds to the
presynaptic membrane, where is it
transported to?
154. What is spastic paralysis induced
by?
155. What is the diagnosis of tetanus
toxin?
156. What are the treatments for
tetanus toxin?
157. How do you prevent getting the
tetanus toxin?
158. What is Listeria and where is it
found?
159. What should individuals at risk
for Listeria avoid?
160. Where is Corynebacterium
diptheriae found?
161. What does cutaneous diphtheria
cause?
162. How is Diphtheria
(Corynebacterium diptheriae)
diagnosed?
163. How does the Elek test help
identify gram positive bacteria?
164. How is Diphtheria treated?
165. What antibiotics are used to
Diphtheria?
166. How do you prevent Diphtheria?
167. Which bacterium cell wall
contains a waxy lipid called mycolic
acid?
TeNT binds to the presynaptic membrane of the
neuromuscular junction.
Spinal cord
The spastic paralysis induced by the toxin is due to the
blockade of neurotransmitter release from spinal inhibitory
interneurons
 Characteristic muscular contraction
 The bacteria are rarely isolated from clinical samples
because it grows slowly and is sensitive to oxygen.
 Thorough cleaning of wounds to remove endospores
 Passive immunization with immunoglobulin directed
against the toxin
 Administration of antimicrobials
 Active immunization with tetanus toxoid
By immunization of tetanus toxoid
• - It is a Gram-positive non-spore-forming, coccobacillus
• Found in soil, water, mammals, birds, fish, and insects
• At risk individuals should avoid undercooked vegetables,
unpasteurized milk, undercooked meat, and all soft
cheeses
• Ubiquitous on plants and in animals and humans
• Cutaneous diphtheria causes cell death and formation of a
pseudomembrane in the trachea that causes suffocation
Initial diagnosis is based on the presence of pseudomembrane
Absolute identification is based on the Elek test
Antibodies against diphtheria toxin react with toxin in a
sample of fluid from the patient
Administration of antitoxin to neutralize toxin before it binds
to cells
Penicillin and Erythromycin kills the bacteria
Immunization with the DPT vaccine
TDap ages 11+
DTap ages 6 weeks+
Mycobacterium
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Gram Positive Bacteria
168. What advantage does a cell wall
of mycolic acid provide?
169. What are three main
mycobacterium diseases?
170. What is Tuberculosis?
Slow growth
Protection from lysis once the bacteria are phagocytized
Capacity for intracellular growth
Resistance to gram-staining, detergents, many antimicrobial
drugs and desiccation
Tuberculosis
Leprosy
Opportunistic infections in AIDS patients
Respiratory disease caused by Mycobacterium tuberculosis
171. Virulent strains of M. tuberculosis Cord factor
contain what cell wall component that
is necessary to cause the disease?
172. What are the three types of
Primary, Secondary and Disseminated TB
tuberculosis?
173. What are the differences between
Primary results from the initial infection with M.
the three types of TB?
tuberculosis
Secondary: Reestablishment of an active infection after a
period of dormancy
Disseminated results when the infection spreads throughout
the body
174. How is Tuberculosis diagnosed?
Tuberculin skin tests identify individuals with previous
exposure to M. tuberculosis. A hard and red swollen bump
will be present at the test site in 48 hours.
175. How do you treat Tuberculosis?
Common antimicrobials are not effective in treating M.
tuberculosis. A combination therapy must be used for a 9-18
months to treat the disease.
176. How is M. tuberculosis
Prophylactic antibacterial drugs are used to treat patients who
prevented?
have converted from a negative skin test to a positive skin test
or were exposed to active cases of TB.
Immunization with BCG vaccine is used in countries where
TB is common.
177. What causes Leprosy (Hansen’s
Caused by Mycobacterium leprae. Transmission is contact
disease)?
person to person or break in the skin. Bacteria have never
been grown in cell-free culture. They can only be grown on
foot pads of mice or armadillo scales.
Cases of leprosy are becoming epidemic
178. Two different types of Leprosy
Tuberculoid leprosy-Non-progressive disease that is
characterized by loss of sensation in regions of the skin.
Lepromatous leprosy- Produces gradual tissue destruction
that results in the loss of facial features, digits and other body
structures.
179. How is Leprosy diagnosed?
Diagnosed based on signs and symptoms.
 Tuberculoid leprosy- loss of sensation in skin lesions
 Lepromatous leprosy-disfigurement

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Gram Positive Bacteria
180. How is leprosy treated?
181. Prevention of leprosy
182. Mycobacterial infections in AIDS
patients are a result of ingestion of
what?
183. Mycobacterial infections in AIDS
patients can result in what?
184. What gram positive bacteria are
common in soils rich in organic matter?
185. Nocardia asteroides produce
opportunistic infections in which sites?
186. What is mycetoma?
187. Prevention of nocardial disease
involves avoiding what substance?
188. Actinomyces israelii is most
commonly associated with what type of
infections?
189. Is actinomyces israelii a normal
flora or parasite?
190. What is a furuncle?
191. What are carbuncles?
192. What is cellulitis?
193. What causes scalded skin
syndrome?
194. What is enterointoxication?
Combination of antimicrobial drugs. Lifelong treatment is
sometimes needed. These medicines cause severe birth
defects, so women must have their tubes tied before treatment
can begin.
Primarily prevented by limiting exposure to the pathogen.
BCG vaccine provides some protection
Contaminated food or water
Massive organ failure
Nocardia asteroides
1. Pulmonary infections (from inhalation of the bacteria,
which then produce pneumonia)
2. Cutaneous infections (bacteria in wounds)
3. Central nervous system infections (meningitis results from
spread of bacteria in the blood.)
A painless, long-lasting infection characterized by swelling,
pus production, and draining sores.
Exposure to the bacterium in soil.
Crainiofacial infections (eg., post-dental procedure) , soft
tissue infections (after human bite wounds) and maxillary
osteomyelitis.
The organism can be a normal flora of the normal host.
Infected hair follicle  abscess/ boils
Usually caused by Staph auerus
Larger than a furuncle; usually it is a mass of furuncles
Infected hair follicle  abscess/ boils
Usually caused by Staph auerus
Soft tissue infections that spreads quickly between tissue
planes and can lead to septicemia (blood poisoning) and death
exfolatin toxin from Staph aureus
diarrhea caused by a toxin that is just part of the bacterium,
not released by it. It is not an infection.
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