Brainscape's Knowledge GenomeTM

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


See full index

Microbiology > 4. Skin infections > Flashcards

4. Skin infections Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Is Staph. aureus G+ or G-?

A

G+

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

Where is Staph. aureus most commonly found on the body?

A

In the nostrils or skin (commensal bacteria)

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

What is panton valentine leucodin?

A
  • Toxin produced by S. aureus
  • Virulence factor
  • Leads to a necrotising infection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is exfoliative toxin?

A
  • Toxin produced by S. aureus
  • Cleaves the epidermis
  • Blistering
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is TSST-1?

A
  • Toxic shock syndrom toxin 1
  • Produced by S. aureus
  • Causes sickness, fever, malaise => organ failure
  • Related to tampons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do we see if the S. aureus infection is within the top layer of the skin (stratum corneum)?

A

Impetigo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a ‘boil’ and ‘carbuncle’?

A

Boil - abscess of the hair follicle

Carbuncle - abscess of several adjacent follicles

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

What is a deep (full thickness involvement of epidermis) form of impetigo called?

A 
Ecthyma
• firmly adherent crust
• won't come off
• surface of skin is dying
• common after infected insect bites
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is infection and inflammation of a hair follicle called?

A

Folliculitis

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

Describe impetigo

A
  • S. aureus infection on surface of epidermis
  • Honey-coloured crust on eroded base
  • Mainly occurs around the nose and mouth
  • Blisters can be easily broken and cause erosions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is bullous impetigo?

A

S. aureus is making the exfoliative toxin on the surface of the epidermis

Local infection

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

What is Staphylococcal scaled skin syndrome?

A
  • Condition caused by the exfoliative toxin
  • Toxin has entered from skin into blood
  • Toxin is also causing cleavage of the epidermis distant to the origin of the infection (desquamation of the epidermis)
  • Systemic infection
  • Mucous membranes not affected
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Who does Staphylococcal scaled skin syndrome affect and how do we treat it?

A
  • Children under age of 5 - related to immature immune system
  • Treat with antibiotics and emollients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is toxic epidermal necrolysis?

A
  • Widespread desquamation of the skin
  • Mucous membranes are affected
  • Result of an allergic reaction to a drug
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does Staphylococcal scaled skin syndrome affect?

A

Only the skin

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

What is Treponema Pallidum and what does it increase the transmission of?

A
  • Gram negative spirochete
  • Cause of Syphilis
  • Increases transmission of HIV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the 3 phases of syphilis

A

1) Primary (3-8 weeks)
• Painless ulcer (chancre) at inoculation site (genital or oral)
• Lasts a few weeks then heals

2) Secondary (6-12 weeks)
• Disseminated infection, generalised rash and lymphadenopathy
• Warty lesions around perineum, axillae and groins
• Gets better and enters latent phase
• Patient can be asymptomatic for several years but can lead to tertiary syphilis without treatment

3) Tertiary syphilis (years later)
• Skin, neurological and vascular manifestations
• e.g. dementia, depression, dilatations of thoracic aorta

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

What is congenital syphilis?

A
  • Acquired perinatally (trans-placental transmission from mother with latent syphilis)
  • Early and late manifestations
  • Most of these babies die before or prematurely after birth
  • Skin ulcers, bony defects, saddle nose, blindness etc.
  • All pregnant mothers are screened
19
Q

What are gummatous skin lesions?

A
  • Caused by syphilis, but very rare now
  • Ulcerating lesions of the skin
  • Often with destruction around the oro-nasal region
20
Q

How do we treat syphilis?

A

Penicillin antibiotics

21
Q

What are the 4 most important human herpes viruses and what do they cause?

A
  • HHV-1 (HSV-1) - cold sores
  • HHV-2 (HSV-2) - genital warts
  • HHV-3 (varicella zoster) - chicken pox / shingles
  • HHV-4 (EBV) - infectious mononucleosis (glandular fever)
22
Q

What does HHV-8 cause?

A

Kaposi Sarcoma - cancer in endothelial cells and lymphatics

23
Q

Which herpes viruses show latency?

A

All viruses

24
Q

What are the 3 types of clinical presentations of the herpes simplex virus (1/2)?

A
  • Vesicular rash (2 weeks)
  • Eczema herpeticum
  • Herpes encephalitis
25
Q

What is stomatitis and what HHV is it common in?

A
  • Inflammation of the mouth and lips

* First presentation of HSV-1

26
Q

Describe eczema herpeticum and the treatment

A
  • Small, punched out ulcers around the skin

* Treatment with acyclovir and emollients, as well as treatment for other associated infections

27
Q

How do you treat someone with eczema herpeticum + impetiginisation by Staph. aureus?

A
  • IV antibiotics
  • IV acyclovir
  • Emollients
  • Topical steroids
28
Q

How is VZV transmitted?

A

Inhalation and person-to-person contact

29
Q

How does VZV present?

A
  • Patient feels unwell, with malaise and headache
  • Rash a day or so later
  • Rash is concentrated mostly on the face (less on body, and even less on the limbs)
30
Q

Where does VZV live when latent?

A

Dorsal root ganglions of the associated sensory cutaneous nerves

31
Q

How does VZV present when activated?

A
  • Shingles
  • Rash along one dermatome
  • Does not cross the midline
  • Can cross into several dermatomes if immunosuppressed
  • Can be bullous (blistering)
  • May suffer from post-herpetic neuralgia (lasting, burning pain)
32
Q

What happens if the opthalmic division of the trigeminal nerve is involve with VZV?

A
  • Opthalmic herpes zoster
  • Keratitis - inflammation of the cornea
  • Inflammation at the back of the eye => blindness
33
Q

What can happen if there is involvement of the tip of the nose in VZV?

A
  • Nasociliary nerve is a branch of V1 that supplies the nose and back of the eye
  • Involvement of the tip of the nose can indicate involvement at the back of the eye
34
Q

Who is the shingles vaccine given to and what does it do?

A
  • Over 70s
  • Can help prevent it
  • Less severe shingles if they get it

(children can be vaccinated against chicken pox so will not run the risk of developing shingles)

35
Q

What are dermatophytes?

A

• Type of skin fungal infection e.g. Trichophyton rubrum - commonest cause of athletes foot, nail infections etc.
• Long hyphae, grow from tip
• Cause Tinea (suffic followed by name of body part)
e.g. Tinea unguium = dermatophyte infection of a nail

36
Q

How does Tinea unguium present, how can it be confirmed and treated?

A
  • Yellow, crumbly nail
  • Confirmation with nail clipping and sending for culture (4-6 weeks)
  • 3-month course of anti-fungal tablets
  • Creams don’t penetrate deep enough into the nail matrix
37
Q

What is Tinea capitis and who does it affect?

A
  • Dermatophyte infection of the scalp
  • Only occurs in children
  • Adults have anti-fungal chemicals in the sebum
38
Q

What is Tinea manuum?

A

Ringworm

39
Q

What is the dermatophyte infection of the feet, groin and face called?

A
  • Tinea pedis
  • Tinea cruris
  • Tinea facei
40
Q

Where do yeasts usually grow?

A

Warm, wet surfaces e.g. genitalia, groin, under the breasts, axillae

41
Q

What is Candida intertrigo and how can it be treated?

A
  • Intertrigo = inflammation of a body crease
  • Seen in mouth, genital area, under the breast and in axilla
  • Satellites around the main infection
  • Treated with topical anti-fungal
42
Q

What is Sarcoptes scabei?

A
  • Scabies - human skin-to-skin contact disease
  • Female mites burrow under stratum corneum and male mites walk on skin
  • Asymptomatic for first 4 weeks
  • Then a type IV hypersensitivity to the mite and it’s faeces
  • Itchy, ecematous rash
  • Crusted scabies - immunosuppressed patient has thousands of mites on the skin
43
Q

How can scabies be treated?

A
  • Insecticide cream all over body
  • Left for 12 hours
  • Repeated 5-7 days later
  • Treat all household contacts
  • Wash all clothes and bedding over 55ºC

Microbiology (6 decks)

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