29. Bacterial Infections Flashcards

1
Q

What is this bacterial infection? Describe it and where it is commonly located

A

Superficial bacterial infection: Impetigo

Small vesicles that burst–> replaced by thick honey colored crusts

Most in mouth, nose and extremeties

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

What is the causitive agent in this infection?

A

Often Staph. Aureus. Sometimes Strep. pyogenes

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

IMpetigo HE… What do we expect to see?

A

Crust in the stratum corneum have lots of neutrophils

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

What happens to the skin in Bullous Impetigo?

A

Toxins cause blistering… keritinocytes are destroyed

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

Awww…. whats going on with this little nugget?

A

Scalded Skin Syndrome

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

Agent responsible for this:

How does it cause this?

A

Staph aureus

exotoxins: Epidermolytic toxin A and Toxin B cause intraepidermal splitting through granular layer

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

What is destroyed froma cellular standpoing in Scalded Skin?

A

The desmosomes jnxs in the stratum granulosum are destroyed

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

Baby comes in with tender skin and macular eruption–> they quickly turn into flacid bullae. Its all over the face, neck, trunk and groin. Ddx?

A

Scalded skin syndrome

good prognosis in kids

may go to septicemia in adults

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

Describe the expected HE of scalded skin syndrome

A

Bullae at surface of skin… surface of epidermis and keritinocytes are destroyed.

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

Pt comes in with diffuse weepy inflammation on the shins. You test it and find its B-hemolytic steptococci.. Dx

A

Cellulitis (deep pyogenic infection)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe Cellulits

A

Diffuse inflammation of CT of skin and deeper soft tissues

B-hemolytic strep/coagulase + staph

more common on legs with expanding erythema (tender)

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

Pt presents with sharpy outlined edematous, erythematous and tender plaque with elevated borders. Your attending says this is often seen in the elderly, but more often on the legs. Dx?

A

Erysipelas

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

Causitive agent of Erysipelas

A

S. pyrogenes

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

Describe what organs systems/vasculature are involved in this.

A

Erysipelas

Bacterial skin infection involving the upper dermis and superfical cutaneous lymphatics

-sharply outlined edema, erythema, tender, painful plaque

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

Describe the HE of Eryipselas and how its different then Scalded skin

A

Both have lots of edema and neutrophils, but this is located deeper in the upper dermis while SSS is more superficial and involves the epidermis/keritinocytes

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

Pathology of Verrucae (image is verrucae vulgaris)

A

Epidermal hyperplasia

Koilocytosis (cytoplasmic vaculoization) of upper epidermal layer. See infected cells show keratohyaline granules with intracytoplasmic aggregates

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

What do we notice about the HE of verrucae ?

A

See infected cells show keratohyaline granules with intracytoplasmic aggregates

18
Q

What is the dominant feature of this HE?

A

Koilocytosis: cytoplasmic vaculozation of the upper epidermis

19
Q

YUUUCK… what is this?

Causitive agent?

A

Condyloma Accuminatum

HSV 6 or 11 most of the time for STD

20
Q

High risk HPV

A

16, 18, 31, 33

(most are 6 and 11)

21
Q

General charactestics of condyloma accuminatum

A

single or multiple paplular lesions, pearly, filiform, fungating, cauliflower or plaque like

22
Q
A
23
Q

Defining feature of condyloma accuminata?

A

from HPV

See the koiliocytes

24
Q

HSV more common in kids, seen on lips (coldsores or gingivomatitis)

-lesions in group of clear vesicles that heal w/out scarring

A

HSV1

25
Q

Mom brings her infant to clinic because her daughter had a diffuse rash with bumps all over and now some are blistering. You notice a mix of macules, vesicles and pustules all over.

Dx?

A

Varicella Zoster Vius

26
Q

You just informed a dad that his daughter has chicken pox. He said he’s been giving his daughter meds to help with the pain and that none of the kids touched any of the vesicles, so he doesn’t think the other kids will get it…. set him straight on a few points

A

DO NOT give child Asprin (Reyes) and tell him it spreads via respiratory route so it doesn’t matter if they didn’t touch them.

27
Q

Woman comes in with a rash on one side that is burning and painful.. Dx?

A

Herpes Zoster— shingles

Recurrace of VZV; latent rxn seen in elderly and immunocompromsed

Unilateral distribution

28
Q

Explain the pathology of this virus

A

Acantholysis of epidermis, see multinucleated keratinocytes with intranuclear inclusions

Perineurial and intraneurial inflammation

29
Q

Notice the large cells that are multinucleated keritinocytes with intranuclear inclusions… what are these and when do we see them

A

cowdry type A includions seen in HSV

30
Q

Where does acantholysis occur in HSV

A

acantholysis of epiderms

31
Q

What is this indicative of?

A

Tzank smear

use to make rapid diagnosis of HSV when taking sample from open vesicle then stain with Giemsa stain. Not as sensitive

32
Q

Cutaneous infection d/t large brick shaped DNA

A

Molluscum contagiousum

33
Q

Who gets mol.contagiousum and how and where

A

acquired infection from close contact of eyelids, face, axilla

Children, see in immunosuppresed pts such as HIV

SUPER contagious

Also STD–on penis, vulva, groin

34
Q

Pathology of Molluscum Contagiousum

A

Inverted nodule… crater like

Eosinophilic cytoplasmic bodies = Hernderso-patterson bodies

35
Q

Very itchy papulovesicular eruption on the hands (other sites are the fingers, penis, umbilicus, waistband and axilla)

A

Scabies

36
Q

How is scabies contacted and when does it present

A

From prolounged direct human contact (not really fomites) see the eruption 4 weeks after infestation

37
Q

YOu suspect dermatophytosis infection in pts nail, what test do you perform?

A

KOH rapid prep– see branching of septae

38
Q

Common apperance of dermatophytosis

A

Scaly, erythematous plaques, often annular

39
Q

What stain do we need to identify a dermatophyotosis (tinea) infection in the superfical stratum corneum?

A

PAS stain; note the fungal elements in the stratum corneum

40
Q

Dx?

A

Tinea versicolr… superficial infeciton, seen in tropical climates caused by Malassezia globosa

See hyperpigmentation