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Flashcards in T1- Infectios Dz of Skin Deck (99)
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0
Q

What are the three types of normal flora?

A
  1. Diptheroids (Propionbacterium acnes)
  2. Micrococci (Staphylococcus epidermis)
  3. Yeast (Candida albicans)
1
Q

What environmental conditions allow for our Normal flora to survivie?

A

dry and salty conditions

2
Q

______ = Bacterial infection, follicle associated lesion… types include comedo, whitehead, blackhead, pustule, and cystic

A

Acne

3
Q

What is the most common mode of transmission of acne (Propionibacterium acnes)?

A

Endogenous

4
Q

What are the virulence factors associated with acne?

A

Lipase, inflammatory mediator, other enzymes

5
Q

What is the treatment for most acne?

A

Antibiotics (topical or oral), Isotretinoin

6
Q

What are the two bacteria that cause impetigo?

A
  1. Staphylococcus aureus

2. Streptococcus pyogenes

7
Q

Peeling of the skin =

A

impetigo

8
Q

Associated with a number of diseases, including impetigo ; Enzymes = Coagulase, Hyaluronidase, Staphylokinase, Lipases ; Most studied non-spore forming pathogen

A

Staphylococcus aureus

9
Q

Impetigo, peeling of the skin, can be caused by Staphylococcus aureus or Streptococcus pyogenes, or may be caused by a mixture of the two. In cases where Impetigo is caused by a mixture of the two, is the onset at the same time? Or one before the other?

A

S. pyogenes begins is ALL cases of the disease, but LATER S. aureus takes over and produces a bacteriocin that destroys S. pyogenes

10
Q

What is the mechanism of transmission associated with impetigo?

A

Transmitted by direct contact, via fomites, and mechanical vectors

11
Q

When is the peak incidence of Impetigo?

A

Summer and Fall

12
Q

______ looks like peeling skin, crusty and flaky scabs, or honey colored crusts

A

Impetigo

13
Q

Where is Impetigo most commonly found?

A

Mouth, Face, and Extremities, but can occur anywhere on the skin

14
Q

Can a patients symptoms suggest whether the infection is caused by Staph or Strep?

A

NO

15
Q

T/F Using SEM (scanning electron micrograph) and colonies of Staphylococcus aureus could confirm the causative agent of impetigo.

A

true

16
Q

What is the primary method of identifying Staphylococcus aureus?

A

Positive coagulase test

17
Q

_________ = Beta Hemolytic, M protein, and is associated with impetigo

A

Streptococcus Pyogenes

18
Q

What is the pathogenesis of Streptococcus pyogenes?

A

Involves the conversion of plasminogen to plasmin, which can degrade host tissue

19
Q

What are the virulence factors associated with Impetigo caused by Staphylococcus Aureus?

A

Exfoliative toxin A, coagulase, other enzymes

20
Q

What are the virulence factors associated with Impetigo caused by Streptococcus Pyogenes?

A

Streptokinase, plasminogen-binding ability, hyaluronidase, M protein

21
Q

What tests would you perform to diagnose Impetigo caused by Staphylococcus aureus?

A

Routinely based on clinical signs, when necessary, culture and Gram stain, coagulase and catalase tests, multitest systems, PCR

22
Q

In what age group do you most often see Impetigo caused by Staphylococcus Aureus?

A

older children or adult

23
Q

In what age group would you most often find Impetigo caused by Streptococcus pyogenes?

A

newborns; may have some involvement in all impetigo (preceding S. aureus in staphylococcal impetigo

25
Q

_______ = Bacterial or Fungal infection of the dermin and subcutaneous tissues; lymphagitis; immunocompromised individuals are at risk

A

Cellulitis

26
Q

What are the signs and symptoms of Cellulitis?

A
  1. Pain
  2. tenderness
  3. swelling
  4. warmth
    Fever and swelling of the lymph nodes in the area may also occur
27
Q

What is caused by red lines leading away from area that become visible as a result of microbes and inflammatory products being carried by the lymphatic system?

A

Lymphangitis

28
Q

What organisms cause cellulitis?

A

S. aureus

S. pyogenes

29
Q

What is the most common mode of transmission of cellulitis?

A

parenteral implantation

30
Q

What are the virulence factors of Cellulitis caused by S. aureus?

A

exfoliative toxin A, coagulase & other enzymes

31
Q

What are the virulence factors of Cellulitis caused by S. pyogenes?

A

Streptokinase, plasminogen-binding ability, hyaluronidase, M protein

32
Q

What is the treatment of cellulitis? (for both organisms)

A

Aggressive treatment with oral or IV antibiotic (cephalexin); surgery sometimes necessary

33
Q

A 12 week old baby is brought into the ED and presents with bullous lesions and desquamation of the skin. Baleigh suspects which bacterial infection to be the cause of this baby’s condition?

A

Staphlococcal Scalded Skin Syndrome (SSSS)

34
Q

What causes the major signs and symptoms of SSSS?

A

Exofoliative toxins A & B

35
Q

What is the most common modes of transmission of SSSS?

A

direct contact and droplet contact

36
Q

How is SSSS prevented?

A

by eliminating carriers in contact with neonates

37
Q

What is the treatment of SSSS?

A

immediate systemic antibiotics (cloxacillin or cephalexin)

38
Q

What is the distinguishing feature of SSSS?

A

split in skin occurs WITHIN epidermis

39
Q

What are 5 characteristics of Gas Gangrene?

A
  1. bacterial infection
  2. anaerobic
  3. toxins (Alpha toxin, exotoxins)
  4. gas formation
  5. two forms (localized & diffused)
40
Q

What is the causative organism of gas gangrene?

A

Clostridium perfringens

41
Q

What is the most common modes of transmission of gas gangrene?

A

vehicle (soil), endogenous transfer from skin, GI tract, reproductive tract

42
Q

Holly was correct in the diagnosis, how can she now prevent the spread of the gas gangrene infection?

A

clean the wounds

debride dead tissue

43
Q

Once the wounds have been cleaned what must Holly now prescribe the patient in order to treat gas gangrene?

A

Cephalosporin (surgical removal & oxygen therapy may also be needed)

44
Q

What are 5 characteristics of Gas Gangrene?

A
  1. bacterial infection
  2. anaerobic
  3. toxins (Alpha toxin, exotoxins)
  4. gas formation
  5. two forms (localized & diffused)
45
Q

What is the causative organism of gas gangrene?

A

Clostridium perfringens

46
Q

Holly has a patient she suspects has gas gangrene, what cultures/tests can she perform to determine the diagnosis?

A

Gram stain, CT scans (for abdominal infections), X-ray, clinical picture

47
Q

Steph’s diagnosis of leprosy has been confirmed, what should she do to treat this patient’s condition?

A

use multidrug treatment including rifampin and dapsone; varies with form of leprosy

48
Q

What is the causative organism of Hansen’s disease (Leprosy)?

A

Mycobacterium leprae

49
Q

What is the most common modes of transmission of Leprosy?

A

not clear, possibly direct or droplet contact; or caused by some mechanical vector.

50
Q

What are the virulence factors of leprosy?

A

binding to Schwann cells, ability to survive within macrophages.

51
Q

Chickenpox re-emerges as____; due to stress, x-ray treatments, drug therapy, or a developing malignancy.

A

shingles

52
Q

elevated lesions filled with fluid = ______.

A

vesicular rash diseases

53
Q

What are 2 viral infections that are vesicular rash diseases?

A

chickenpox

smallpox

54
Q

What is a common, benign vesicular rash disease that affect a dermatome? It can be life-threatening for immunocompromised individuals.

A

Chickenpox

55
Q

Chickenpox is a result of _____.

A

varicella-zoster virus infection

56
Q

What epidemic vesicular rash disease has been considered a bioterrorism agent and has been eliminated due to world-wide vaccine program?

A

smallpox

57
Q

Causative organism for Chickenpox

A

Human Herpesvirus 3 (varicella-zoster virus)

58
Q

Most common modes of transmission of chickenpox

A

droplet contact, inhalation of aersolized lesions fluid

59
Q

Virulence factor for chickenpox

A

ability to fuse cells, ability to remain latent in gangia

60
Q

Diagnosis of chickenpox is based largely on ___

A

clinically appearance

61
Q

Prevention of chickenpox

A

live attenuated vaccine

62
Q

Treatment of chickenpox

A

NONE

63
Q

Causative Organism of Smallpox

A

Variola virus

64
Q

Most common Mode of transmission of small pox

A

droplet contact or indirect contact

65
Q

Virulance factor of smallpox

A

Ability to dampen, avoid immune system

66
Q

Diagnosis of small pox is based on ___

A

clinical appearance

67
Q

Prevention of smallpox

A

live virus vaccine

68
Q

What are examples of maculopapular rash diseases - flat to slightly raised colored bump

A

Measles or rubeola
Rubella
Fifth disease
Roseola

69
Q

Viral infection, Vaccine avaibable but the disease still exists, Koplik’s spots

A

Measles

70
Q

Whats a complication of Measles infection?

A

Subacute sclerosing panencephalitis (SSPE)

71
Q

viral infection, vaccine available in MMR, mild, serious for a fetus

A

Rubella

72
Q

Teratogenic for a fetus, disrupts fetus development

A

rubella

73
Q

viral infection, erythema infectiosum, mild and no vaccine

A

fifths disease

74
Q

viral infection, latent period that reactivates as mononucleosis like or hepatitis-like sysmptoms, immunocompromised individuals are at risk

A

roseola

75
Q

Causative organism for Measles and most common mode of transmission

A

measles virus

droplet contact

76
Q

virulence factor and preventation of measles

A

syncytium formation, ability to suppress CMI

Live attenuated vaccine MMR

77
Q

Causative organism of rubella and most common mode of transmission

A

rubella virus

droplet contact

78
Q

virulence factor and preventation of rubella

A

in fetuses: inhibition of mitosis, induction of apoptosis and damage to vascular endothelium ** read that again! thats important

MMR vaccine

79
Q

Causative organism of fifth disease and most common mode of transmission

A

parvovirus B19

droplet contact and direct contact

80
Q

causative organism of roseola

A

human herpesvirus 6 or 7

81
Q

Distinguishing feature of measles

A

starts on head, spreads to whole body and lasts over a week

82
Q

distinguishing feature of rubella

A

milder red rash, lasts approximately 3 days

83
Q

distinguishing feature of fifth disease

A

“slapped face” rash first, spreads to limbs and trunk, tends to be confluent rather than distinct bumps

84
Q

distinguishing feature of roseola

A

high fever precedes rash stage - rash not always present

85
Q

two agents that cause warts

A

papillomas and molluscum contagiosum

86
Q

viral infection, benign, nearly everyone is infected

A

papillomas

87
Q

types of virus that causes plantar warts

A

hpv-1

88
Q

type of virus that causes flat warts

A

hpv-3
hpv-10
hpv-28
hpv-49

89
Q

virual infection, distributed world-wide, spread by contact, and inclusion bodies contain viruses

A

molluscum contagiosum

90
Q

causative organism of warts

A

hpv

91
Q

most common mode of transmission for warts

A

direct contact, autoinoculation and indirect contact

92
Q

diagnosis of warts is by __ and preventation

A

clinical diagnosis, PCR

avoid contact

93
Q

most common modes of transmission of molluscum contagiosum

A

direct contact, including sexual contact, autoinoculation

94
Q
large skin lesions can be due to 
-
-
-
-
A

Leishmaniasis
Cutaneous anthrax
Ringworm
Superficial mycoses

95
Q

Protozoan infection (cutaneous/mucocutanous or systemic) zoonosis and no vaccine

A

leichmaniasis

96
Q

bacterial infection, endosporulation and germination, untreated cases can be fatal and vaccine is available

A

cutaneous anthrax

97
Q

Fungal infections caused by dermatophyte

A

Mycosis, Ringworm.

Tinea Capitus (head)
Tinea barbae (beard)
Tinea corporis (body)
Tinea cruris (groin)
Tinea Pedis (foot)
Tinea poris (hand)
Tinea unguium (nail)
98
Q

What is a type of superficial mycosis infection that has cosmetic effects without inflammation?

A

Tinea Versicolor

99
Q

What are two types of superficial mycosis infections?

A

Yeast infection

Tinea Versicolor