Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Semester 3 > General Pathology 300 (Defense mechanisms and types of infections) > Flashcards

General Pathology 300 (Defense mechanisms and types of infections) Flashcards

1
Q

Patterns of infections

A

different ways to damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

different ways to damage (different mechanisms of infections)

A

1) The invasive organism produces local damage (e.g., warts)

2) The invasive organism is toxic (poisonous) to the host (e.g. botulism)

3) The invasive organism produces little local damage but has widespread effects (e.g., HIV)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

spread of infection within host – 3 types

A

1) Directly - some pathogens produce enzymes that damage cell membranes, enabling them to move rapidly from cell to cell

2) Via natural channels such as membranes (meninges, pleura, peritoneum) and vessels (lymphatic, blood)

3) Through nerves or through phagocytes (e.g., herpes virus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Mode of action (infection)

A

Mode of action of a pathogen refers to how the organism produces a pathologic process.

Great variation exists.

E.g.
1) Some intracellular pathogens, like viruses, invade cells and interfere with cellular metabolism, growth and replication.

2) Other organisms cause cell death.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Factors affecting occurrence and spread of infection

A

1) Pathogenic factors

2) Host factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

1) PATHOGEN FACTORS

A
  1. Virulence – the relative power and degree of pathogenicity
    “the severity or harmfulness of a disease or poison.”
  2. Dose – increased numbers are more effective
  3. Site of infection – some sites are more easily infected
    E.g.
    Mucous membranes
  4. Synergism between different pathogens (i.e. one organism can impair external defenses and permit another to enter).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

mucous membranes – infection

A

“The mucosal surfaces of the body are highly vulnerable to infection and possess a complex array of innate and adaptive mechanisms of immunity”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Pathogen factors, simplified

A

strength
= virulence

numbers
= dose

location of attack
= site

teamwork
= synergism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

2) HOST FACTORS

A

Resistance to infection

Immune competency

Leukocyte count

Necrosis and ischemia of a tissue (e.g., anaerobic bacteria)

E.g.
via factors like age (older people, very young people, immunocomprimised people, etc.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Diagnosis

A
  1. Direct visualization of organism
  2. Detection of microbial antigen
  3. Search for clues produced by the host immune response to specific micro-organisms
  4. Isolation of organism in culture
  5. Detection of specific microbial nucleotide sequences
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Opportunistic infections

A

An opportunistic infection is any infection that results from a defective immune system that cannot defend against pathogens normally found in the environment. These infections are usually seen in patients with impaired defenses against disease.

I.e.
people with optimal immune system function will generally not be getting these, or not getting them as frequently (?)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Opportunistic infections (life threatening infectious diseases)

A

Life threatening infectious disease occurs when immunity is weak or suppressed

(e.g. transplant patients, AIDS patients, old age, newborns, malnourished, burn victims, etc).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

why is immune system comprimised in severe burn patients?

A

“After the burn, the ability of neutrophils’ oxidative burst decreases, which in turn weakens phagocytosis [10,29]; there is a decrease in the speed of motility during chemotaxis [30,31] and decreased bactericidal capacity [14], which ultimately reduce innate immune function.”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Bacterial Infection types

A

Staphylococci
Streptococci
Pneumococci
Meningococci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

cocci

A

spherical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

STAPHYLOCOCCAL INFECTIONS

A

“Staph”

Among the most common bacteria normally residing on the skin

Over 30 subtypes

Cause a multitude of disease ranging from mild / asymptomatic to severe / fatal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Leading cause of nosocomial and community acquired infections

A

STAPHYLOCOCCI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

most common type (Staphylococcus)

A

Most common - Staphylococcus aureus (S. aureus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

S. AUREUS

A

Extremely virulent

Nonmotile and facultative aerobic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

motile vs nonmotile

A

(of cells, gametes, and single-celled organisms) capable of motion.

Bacterial motility is the ability of bacteria to move independently using metabolic energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

facultative aerobic define

A

These are bacteria that, under normal circumstances, breathe anaerobically but can breathe aerobically when oxygen is available.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

anaerobic respiration define

A

“Anaerobic respiration is respiration using electron acceptors other than molecular oxygen. Although oxygen is not the final electron acceptor, the process still uses a respiratory electron transport chain.”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

respiration, special define

A

BIOLOGY
“a process in living organisms involving the production of energy, typically with the intake of oxygen and the release of carbon dioxide from the oxidation of complex organic substances.”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

how well can S. AUREUS survive

A

Hardy; able to survive on inanimate objects for an extended period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what can S. AUREUS infect

A

Can infect the blood, skin, lungs, soft tissue, joints, bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Risk factors for S. Aureus infection

A

Diabetes, chronic illness

HIV positive

Elderly, newborns, malnourished

Surgical/burn patients

Prosthetics
Etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

prosthetics vs infection (???)

A

“Amputations can be the result of sepsis. Alternately, if you have an amputation, you could develop a pressure injury from a prosthetic or adaptive/assistive device and this could result in an infection that could cause sepsis.”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

infectious diseases caused by STAPHYLOCOCCUS AUREUS

A

Osteomyelitis

Respiratory tract infections

Infectious (septic) arthritis

Septicemia

Endocarditis

Toxic shock syndrome

Food poisoning

Skin infections (cellulitis, mastitis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

management (when infected by S. AUREUS??)

A

..

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

diagnosis

A

Diagnosis - culture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

treatment

A

Treatment - antibiotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

S. Aureus infection – PROGNOSIS

A

Prognosis is generally good although some strains of S. aureus are particularly difficult to treat

E.g. MRSA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

MRSA

A

Methicillin-resistant Staphylococcus aureus

Methicillin = antibiotic

“Methicillin-resistant Staphylococcus aureus is a group of gram-positive bacteria that are genetically distinct from other strains of Staphylococcus aureus.”

“MRSA is responsible for several difficult-to-treat infections in humans.”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

how do S. Aureus strains adapt to antibiotics

A

“Intrinsic Antibiotic Resistance. The resistance rates of S. aureus infection and multidrug resistant strains are increasing, making the clinical anti-infective treatment more difficult.”

“Staphylococcus aureus is notorious for its ability to become resistant to antibiotics.”

“Staphylococcus aureus is capable of becoming resistant to all classes of antibiotics clinically available and resistance can develop through de novo mutations in chromosomal genes or through acquisition of horizontally transferred resistance determinants.”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

de novo mutation

A

“A de novo mutation is any mutation or alteration in the genome of an individual organism that was not inherited from its parents. This type of mutation spontaneously occurs during the process of DNA replication during cell division.”

36
Q

STREPTOCOCCAL INFECTIONS

A

Group A – Streptococcus pyogenes (S. pyogenes)

Group B – Streptococcus agalactiae (S. agalactiae)

37
Q

Streptococcus pyogenes

A

One of the most common bacterial pathogens of human of any age

Causes many diverse diseases of many diverse organs and systems

38
Q

Steptococcus pyogenes – pus vs no pus

A

Can cause suppurative and non-suppurative disease

39
Q

S. pyogenes – transmission

A

Transmission – contact, droplets, foodborne (vehicle)

40
Q

Diseases caused by STREPTOCOCCUS PYOGENES

A

Streptococcal pharyngitis (strep throat) – very common cause of sore throat occurring mostly in children

Scarlet fever – usually follows untreated strep throat and but more severe

Impetigo – skin infection that occurs in children, particularly in hot weather

Cellulitis – acute skin infection

Necrotizing fasciitis – very serious and potentially fatal infection that spreads quickly along fascial planes

41
Q

Streptococcus AGALACTIAE

A

..

42
Q

S Agalactiae – can cause

A

Leading cause of neonatal pneumonia, meningitis, sepsis

Infrequent cause of pyogenic disease in adults
—> Referring to pus (??)
or referring to infections that S Pyogenes causes (??)

43
Q

pyogenic deifne

A

adjective: pyogenic

involving or relating to the production of pus.

44
Q

pyogenic

A

“Pyogenic is a term describing bacteria capable of causing local purulent inflammation or generalized infection, and Streptococcus pyogenes is aptly named after this characteristic.”

“Streptococcus pyogenes (GAS) is known to cause pyogenic infections of the pharynx and skin.”

45
Q

Streptococcus agalactiae – Treatment

A

Rapid administration of antibiotics is essential

46
Q

S. Agalactiae (group B strep) and pregnancy

(GROUP B strep in pregnancy)

A

Pregnant women are routinely screened

“Group B Streptococcus (GBS) is a gram-positive bacteria that colonizes the gastrointestinal and genitourinary tract. It is known to cause both early onset and late onset infections in neonates.”

“In women, GBS most often is found in the vagina and rectum. This means that GBS can pass from you to your fetus during labor. This is rare.”

“While GBS may not be harmful to you, it can be very harmful to your baby. If you’re pregnant, you can pass it to your baby during labor and childbirth.”

47
Q

GBS and strep

A

Group B Streptococcus (group B strep, GBS) is a type of bacteria often found in the urinary tract, digestive system, and reproductive tracts. The bacteria come and go from our bodies, so most people who have it don’t know that they do. GBS usually doesn’t cause health problems.

“Health problems from GBS are not common. But it can cause illness in some people, such as the elderly and those with some medical conditions.”

“some babies can become very sick from GBS. Premature babies are more likely to be infected with GBS than full-term babies because their bodies and immune systems are less developed.”

48
Q

PNEUMOCOCCAL INFECTIONS

A

Pneumococcus or Streptococcus pneumonia (S. pneumonia)

Can cause pneumonia, sepsis, otitis media, meningitis

49
Q

MOST COMMON CAUSE OF COMMUNITY ACQUIRED PENUMONIA

A

Pneumococcus – AKA Streptococcus pneumonia (S. pneumonia)

50
Q

most common cause of nosokomial pneumonia

A

Staphylococcus aureus (including methicillin-resistant Staphylococcus aureus [MRSA])

51
Q

Pneumococcal infections –> who is susceptible?

A

Very young and very old particularly susceptible

52
Q

Pneumococcus

A

Often follows influenza, viral respiratory infections

Risk factors include chronic disease and alcohol abuse, immunosuppression, etc.

53
Q

Most common cause of bacterial meningitis in adults, infants and toddlers

A

Streptococcus Pneumonia

54
Q

MENINGOCOCCAL INFECTIONS

A

Meningococci cause meningitis and septicemia

Symptoms are usually severe and can include headache, nausea, vomiting, photophobia, lethargy, rash, multiple organ failure, shock, and disseminated intravascular coagulation (DIC)

55
Q

ANAEROBIC BACTERIAL INFECTIONS

A

Anaerobic bacteria are intolerant of oxygen, replicating at sites of potentially low oxygen such as necrotic, devascularized tissues.

56
Q

anaerobic bacteria vs pus

A

These infections are usually suppurative, causing abscess formation and tissue necrosis.

57
Q

Anaerobic Infections – E.g.

A

Diphtheria

Plague (www.merck.com/mmpe)

Botulism (www.merck.com/mmpe)

Cholera

58
Q

Diphtheria

A

An acute pharyngeal or cutaneous infection caused by Corynebacterium diphtheria (C. diphtheria)

59
Q

Diphtheria caused by

A

Corynebacterium diphtheria (C. diphtheria)

60
Q

who is vaccinated? (Diphtheria)

A

Children are routinely vaccinated

61
Q

how does diphtheria spread?

A

The disease spreads by contact and secretions of nose, mouth and skin lesions

62
Q

Diphtheria – SSx

A

Symptoms include nonspecific skin infections (inflammation and necrosis of local tissues)

or pseudomembranous pharyngitis followed by myocardial and neural tissue (heart, nerve, kidney) damage

63
Q

Diphtheria – Tx

A

Tx – antibiotics; prognosis – good

64
Q

Plague

A

Aka Bubonic Plague or Black Death

65
Q

Plague caused by which bacteria

A

Caused by Yersinia pestis (Y. pestis)

66
Q

Plague – Sx

A

Symptoms are either severe pneumonia or massive lymphadenopathy with high fever often progressing to septicemia

67
Q

characteristic feature – pathognomonic feature (?)

A

Enlarged lymph nodes called buboes

68
Q

Plague via

A

Wild rodents carry disease

Transmitted from rodent to human by the bite of a flea vector

Human-to-human transmission occurs by inhaling droplets from infected humans

Highly contagious

Massive human pandemics rare today due to antibiotics

69
Q

Botulism

A

Neuromuscular poisoning caused by Clostridium botulinum

Botulism can be food-borne or wound-borne

Most frequently manifests as a severe form of food poisoning

Common sources include home-canned foods, vegetables, fish, fruits, condiments, meat, dairy

70
Q

Botulism – pathogenesis

A

Bacteria produces toxin that can interfere with release of acetylcholine at peripheral nerve endings (NMJ)

71
Q

Botulism – SSx

A

Symptoms include nausea, vomiting, abdominal cramps and diarrhea followed by weakness and paralysis

72
Q

botulinum spores (?)

A

“Spores are common in the environment” (?)

“botulinum spores are often found on the surfaces of fruits and vegetables and in seafood. The organism grows best under low-oxygen conditions and produces spores and toxins. The toxin is most commonly formed when food is improperly processed (canned) at home.”

73
Q

about spores (botulism)

A

Although the spores are heat resistant, cooking kills the toxins

A spore is a cell produced by spore-forming bacteria (bacillus) to withstand extreme conditions

“It can remain viable for decades”

74
Q

spore define

A

MICROBIOLOGY
(in bacteria) a rounded resistant form adopted by a bacterial cell in adverse conditions.

(??)

75
Q

C. botulinum spores

A

“Spores produced by the bacteria Clostridium botulinum are heat-resistant and exist widely in the environment, and in the absence of oxygen they germinate, grow and then excrete toxins. There are 7 distinct forms of botulinum toxin, types A–G. Four of these (types A, B, E and rarely F) cause human botulism.”

76
Q

Cholera – including SSx

A

Acute infection of the small bowel by Vibrio cholerae

Secretes a toxin that produces copious watery diarrhea

Leads to dehydration, oliguria, and collapse (shock)

circulatory collapse (?)

77
Q

collapse

A

In medicine, collapse can refer to various forms of transient loss of consciousness such as syncope, or loss of postural muscle tone without loss of consciousness. It can also refer to: Circulatory collapse.

78
Q

cholera – how infected

A

Infection is typically through water or seafood that is contaminated with the excrement of infected people

Esp after natural disaster when plumbing structures are affected near ocean

79
Q

Cholera – Tx

A

Treatment – rehydration with water and electrolytes; antibiotics

80
Q

SPIROCHETTE INFECTIONS

A

A spirochete is a slender, spiral, motile bacteria that lives off dead and decaying matter in soil and water.

E.g. Lyme disease, syphillis

81
Q

Lyme disease

A

An infectious multisystemic disorder

Caused by Borrelia burgdorferi

Vector-borne disease carried by a deer tick

Ticks carrying the bacteria can transmit it to mammals by injecting saliva into the host.

82
Q

Lyme disease – Sx

A

Symptoms include skin lesions and a “bull’s eye” rash (erythema migrans). The bacteria reach other organs through the blood and cause nausea, vomiting, neurological and arthritis-like symptoms.

83
Q

Lyme disease – when common?

A

most common tick-borne disease in the states (?)

84
Q

Lyme disease – Tx

A

Treatment - antibiotics

85
Q
A

Semester 3 (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions