Workshop: Skin Infections

Question 1

two broad groups of fungi:

Answer 1

yeast and mold

Question 2

Mold spores germinate to produce ____ _____=
hyphae
• ____ infections
• Tinea corporis, tinea capitis, tinea pedis,
onychomycosis

Answer 2

Mold spores germinate to produce branching filaments=
hyphae
• DERMATOPHYTE infections
• Tinea corporis, tinea capitis, tinea pedis,
onychomycosi

Question 3

• Yeasts are solitary rounded forms that reproduce by
making more rounded forms (____/____)
• CANDIDA

Answer 3

• Yeasts are solitary rounded forms that reproduce by
making more rounded forms (budding/fission)
• CANDIDA

Question 4

what is the morphology

Answer 4

• irreuglar annular border with central clearing. its a large and riased plaque with a roled/scale border.

probably a tinea infection

Question 5

what is the morphology

Answer 5

hyperpifmented plaque with some raising along peripheral border.

central clearing, probably tinea

Question 6

Answer 6

athletes foot; tinia pedis

Question 7

t/f tinea corporis and pedis treatment requries combination treatment with topical corticosteroid and anti-fungal

Answer 7

false. corticosteroids clears fungus from top surface but makes the fungal infection grow deeper into thes kin. loses its central clearing–makes it harder to diagnose.

• Treat a fungal infection with topical antifungal
• Treat cutaneous inflammation (eczema, psoriasis) with topical corticosteroid

• When you don’t know- do a fungal scraping, bacterial swab and/or
take a skin biopsy!

Question 8

Answer 8

majocchi’s granuloma

Treating tinea corporis with a topical steroid
Erythematous Plaque Loses its advancing border

Question 10

Answer 10

tinea

Question 11

ddx

Answer 11

onychomychosis; accumulation of fungal contents underneath the nail bed and causes separation.

could be psoriasis

Question 12

morphology

Answer 12

located on skin folds

erythematous papules coalescing into patches

satellite lesions

candida intriga or diaper rash

Question 13

Answer 13

candida intriga

• Focus on the bright erythematous patches WITH satellite
erythematous papules • These satellite papules = candida infection

Question 14

treatment with diaper dermatitis

Answer 14

its a very common to have secondary candidal infection

• keep the area as dry as possible
• change diaper frequently; especially afer poo
• use barrier cream
• use topical antifungal if candida suspected

Question 15

Question 16

morphology

Answer 16

crusting

erythematous papules coalescine together to form blistering erythematous plaques

probably impetego

Question 17

Answer 17

crusting

erythematous papules coalescine together to form blistering erythematous plaques

probably impetego

Question 18

Answer 18

crusting

erythematous papules coalescine together to form blistering erythematous plaques

probably impetego

• kind of looks like psoriasis

Question 19

bacteria that causes impetigo and mechanism

Answer 19

staph aureus causing local production of exfoliative toxins, separting the keratinocytes within the granular layer. same as in pemphigus (autoantibodies target demosomes)

• it’s contagious; person to person or fomite contact
• infection usually occurs of site of scratching (insect bites, atopic derm)

Question 20

Answer 20

baterial folliculitis

Question 21

lesion caused by bacterial folliculitis

Answer 21

furuncle= entire hair follicle and surrounding tissue involved.

• multiple = carbuncle.

Question 22

treatment for bacterial folliculitis

Answer 22

superficial: antibacterial washes with benzoyl peroxide, topical antibiotics.
- widespread or recurrent- oral beta-lactam antibiotics, tetracyclines or macrolides.

Question 23

Answer 23

carbuncle: larger pustules coalescing onto an inflammatory plaque.

several follicles infected.

• Tx: warm compresses, incision and DRAINAGE, systemic antibiotic
therapy if drainage not possible
• MRSA common

Question 24

cellulitis

Question 25

what layers are affected by cellulitis

Answer 25

deep dermis and subcutaneous tissue causing erythema swelling warmth and tenderness with ill-defined borders

Question 26

4 key signs of inflammation/infection

Answer 26

1. rubor 2. calor 3. dolor 4. tumor

Question 27

which bacterias cause cellulitis

Answer 27

• GAS or staph aureus (diabetic often mixed gram pos, neg, anaerob)

Question 28

Answer 28

cellulitis

Question 29

t/f you should prescribe antibiotics for lower leg lredness and swelling

Answer 29

false. Cellulitis is very rarely bilateral-- must rule out other causes

Question 30

primary morphology

Answer 30

grouped/clustered vesicles. indicative of viral infection

Question 31

Answer 31

groups of clustered vesicles that are now pustules. probably started as a viral infection, then became secondary impetigenized (secondary staph infection)

Question 32

HSV1, 2, 3.

Answer 32

1= oral 2= genital 3= varicella zoster

Question 33

where is latency of hsv virus "stored"

Answer 33

sensory ganglia. Virus replicates at site of infection, travels to the dorsal root ganglia where it becomes latent (exist in non-infectious state in host = evades detection)

Question 34

symptomatic primary infection symptoms

Answer 34

• **gingivostomatitis** in children or **pharyngitis** and mono-like syndrome in young adults- mouth, lips, buccal mucosa, gingivae • Painful erosive balanitis/vulvitis, often involve cervix, buttocks, perineum, dysuria, aseptic meningitis in 10% of females, urinary retention, extragenital lesions

Question 35

what is eczema herpeticum

Answer 35

occurs in someone with barrier disruption in the skin = atopic dermatitis. - widespread disseminated of HSV1 ( or 2) across affected skin.

Question 36

Answer 36

eczema herpeticum

Question 37

Answer 37

eczema herpeticum

Question 38

what are dermatomes

Answer 38

an area of the skin supplied by nerves from a single spinal root

Question 39

Answer 39

juicy vesicles and papules with a clear demarkation evident. shingles

Question 40

Answer 40

shingles

Question 41

Answer 41

shingles

Question 42

treatment of Zoster

Answer 42

- begin antiviral treatment within 72 hours optimally (but up to 7 days after is still beneficial)= **earlier is better** **• Acyclovir, famciclovir and valacyclovir are FDA approved • Decrease severity and duration of skin lesions and pain • IV acyclovir for immunocompromised and those with serious complications**

Question 43

most common complication of shingles

Answer 43

Postherpetic neuralgia = Damage to the sensory nerves following zoster infection, resulting in burning, debilitating pain \> 3 months after shingles episode

Question 44

describe the morphology

Answer 44

vesicles on an erythematous base. DEW DROPS ARE CHARACTERISTIC CHICKEN POX

Question 45

Answer 45

primary varicella infection -

Question 46

whats goin on

Answer 46

erythematous papules - umbilization = ciruses - not pustules = not yellow-- not vesicles cause they are not fluid filled MOLLUSCUM CONTAGIOSUM POXVIRUS

Question 47

treatment for molluscum

Answer 47

- watchful waiting, most resolve on own in months to years BUT it doesn't look really good. topical; cantharidin, podophyllin cream, cryotherapy, curettage etc.

Question 48

Answer 48

HPV

Question 49

Answer 49

HPV; pedunculated on shaft of penis

Question 50

t/f palmar or plantar warts are oncogenic

Answer 50

false. ones that are cerivcal, anogenital warts cause squamous cell carcinoma

Question 51

how does HPV infect the host

Answer 51

it's sneaky. HPV evolved to evade immune surveillance. There is no viremic phase during life cycle so avoids systemic immune response. • 2/3 warts spont regress in 2 years and lesions of multifocal infections often regress concomitantly

Question 52

Answer 52

scabies

Question 53

Answer 53

scabetic nodules of the genitals. erythematous papules

Question 54

scabies treatment

Answer 54

MAKE SURE YOU TREAT ALL FAMILY MEMBESR

Question 55

Answer 55

furuncle due to bacterial folliculitis

Question 56

Answer 56

yeast/candida = moisture and heat causing candida intertrigo

Question 57

Answer 57

scabies

Question 58

Answer 58

shingles on a specific dermatome

Question 59

Answer 59

erysipelas- superficial variant of cellulitis affecting dermis with lymphatic involvemnet vs cellulitis GAS - check for recent strep infection and treat with penicillin