Viral, Bacterial, & Parasitic Skin Infections

Question 1

What are the s/s of condyloma acuminata (genital warts)?

Answer 1

Tiny, painless papules

Evolve into soft, fleshy cauliflower-like lesions (ranging from skin colored to pink or red)

Question 2

How & where does condyloma acuminata occur?

Answer 2

Occurs in clusters in the genital regions & oropharynx

Question 3

How do you dx mucosal HPV?

Answer 3

Whitening of lesion w/ acetic acid application

Question 4

How do you treat condyloma acuminata?

Answer 4

chemical, salicylic acid, cryotherapy, laser & podophyllin

Question 5

What are the s/s of herpes simplex virus 1 & 2?

Answer 5

Prodromal sx 24hrs prior (burning, paresthesias, tingling) –> painful, grouped vesicles on an erythematous base

Question 6

What are the s/s of acute herpetic gingivostomatitis?

Answer 6

Sudden onset fever, anorexia –> gingivitis, vesicles in mouth, tongue, & lips –> grey/yellow lesions

Question 7

What are the s/s of acute herpetic pharyngotonsillitis?

Answer 7

Vesicles rupture –> ulcerative lesions w/ grayish exudates in posterior pharynx

Question 8

What are the s/s of herpes labialis?

Answer 8

Cold sore, fever blister w/ stress/illness

Question 9

How do you diagnose HSV?

Answer 9

PCR = most sensitive/specific test

Tzanck smear

Question 10

How do you treat HSV?

Answer 10

Acyclovir, valcyclovir, famiciclovir

Question 11

What viral family does molluscum contagiosum belong to?

Answer 11

Poxviridae

Question 12

What are characteristics of molluscum contagiosum?

Answer 12

Highly contagious

MC in children, sexually active adults, pts w/ HIV

Question 13

What are s/s of molluscum contagiosum?

Answer 13

Single or multiple dome-shaped, flesh-colored to pearly-white, waxy papules w/ central umbilication

Question 14

How do you treat molluscum contagiosum?

Answer 14

No tx needed

Curettage, cryotherapy, podophyllotoxin.

Topical retinoids if severe

Question 15

How do you treat verruca (warts)?

Answer 15

Most resolve spontaneously within 2 yrs

Topical salicylic acid & plasters

Cryotherapy, electrocautery, CO2, laser, bleomycin

Question 16

How is varicella zoster virus (HHV3) transmitted?

Answer 16

Respiratory droplets, direct contact

Question 17

What are the s/s of varicella (chicken pox)?

Answer 17

Fever, malaise, pruritis

Clusters of vesicles on an erythematous base “dew drops on a rose petal” in different stages*

Begins on face, trunk –> extremities

Question 18

What are the s/s of herpes zoster (shingles)?

Answer 18

VZV reactivation along 1 dermatome of the dormant virus in the spinal root & CN ganglia

Question 19

What are the s/s of herpes zoster oticus (Ramsay-Hunt Syndrome)?

Answer 19

Facial nerve (CN VII) - otalgia, lesions on the ear, auditory canal & TM, facial palsy

Auditory sx: tinnitus, vertigo, deafness, ataxia

Question 20

How do you treat the chicken pox?

Answer 20

Symptomatic tx

Question 21

How do you treat the shingles?

Answer 21

Acyclovir, valacyclovir, famciclovir (given within 72 hrs to prevent PHN)

Question 22

How do you treat Ramsay Hunt Syndrome?

Answer 22

oral acyclovir + corticosteroids

Question 23

What causes cellulitis? How does it occur?

Answer 23

MC caused by S. aureus & GABHS/S. pyogenes

Occurs after a break in the skin

Question 24

What are s/s of cellulitis (locally)?

Answer 24

Macular erythema (not sharply demarcated), swelling, warmth, & tenderness

Question 25

What are s/s of cellulitis (systemically)?

Answer 25

Not common Fever, chills, +/- tender lymphadenopathy, myalgias, vesicles, bullae, hemorrhage & necrosis

Question 26

How do you treat cellulitis?

Answer 26

Cephalexin, dicloxacillin x7-10days Clindamycin or erythromycin if PCN allergic MRSA: IV vanco or linezolid, oral TMP-SMX, doxycycline, daptomycin

Question 27

What causes erysipelas?

Answer 27

GABHS

Question 28

What are s/s of erysipelas?

Answer 28

Well demarcated margins of cellulitis, intensely erythematous (St. Anthony's fire) MC involves the face or skin w/ impaired lymphatic drainage

Question 29

How do you treat erysipelas?

Answer 29

IV PCN Vanco (if PCN allergic or MRSA suspected)

Question 30

Describe vasculitis

Answer 30

See pages 63, 220-223, 340, 343, 438 of PANCE Prep Pearls

Question 31

What are RFs for impetigo?

Answer 31

Warm, humid conditions Poor personal hygiene

Question 32

Where does impetigo occur on the body?

Answer 32

Sites of SF skin trauma, primarily on face & extremities

Question 33

What does nonbullous impetigo look like?

Answer 33

Vesicles, pustules --> "honey-colored crust" MC type, a/w lymphadenopathy

Question 34

What bacteria causes nonbullous & bullous impetigo?

Answer 34

S. aureus MC

Question 35

What are the s/s of bullous impetigo?

Answer 35

Vesicles --> large bullae --> rupture --> thin "varnish-like crusts" Fever, diarrhea

Question 36

What does ecthyma impetigo look like? What bacteria causes it?

Answer 36

Ulcerative pyoderma GABHS

Question 37

How do you treat impetigo?

Answer 37

Topical mupirocin (bactroban) = DOC! x 10 days Bacitracin. Good hygiene. If extensive or sx persist --> Cephalexin, dicloxacillin, macrolides

Question 38

How are scabies transmitted?

Answer 38

Mites are transmitted through prolonged, skin-skin contact or fomites Burrow into skin to lay eggs, feed, & defecate

Question 39

What are s/s of scabies?

Answer 39

Intensely pruritic lesions (papules, vesicles, & linear burrows). Increased at night Commonly found in the intertriginous zones (web spaces btwn fingers/toes, scalp, scrotum, glans, penile shaft, body folds) Usually spares the neck/face

Question 40

How do you diagnose scabies?

Answer 40

Clinically! Skin scrapings of the burrows w/ mineral oil

Question 41

How do you treat scabies?

Answer 41

Topical permethrin = DOC! Applied from neck to the soles of feet for 8-14hrs before showering. Repeat application after 1 week. Lindane (cheaper): DO NOT USE AFTER BATH/SHOWER --> SEIZURES!! Also teratogenic (DO NOT USE IN PREGNANCY, BREASTFEEDING, or CHILDREN<2)

Question 42

What are s/s of pediculosis (lice)?

Answer 42

Intense itching (esp occipital area), papular urticaria near lice bites Nits: white oval shaped eggs at base of hair shafts

Question 43

How do you treat pediculosis?

Answer 43

Topical permethrin = DOC! x 8-10 hrs Capitus: permethrin shampoo x 10mins 2nd line: Lindane (S/E = neurotoxic)