Dermatology- Infections & Toxins

Question 1

Diagnosis: Male Hx hemochromatosis, wound while on dock, edema, erythema, several dark-colored bullae, streaking erythema, fever

Answer 1

Necrotizing Fasciitis caused by Vibreo vulnificus

Question 2

Vibreo Vulnificus

Answer 2

Gram-Neg bacteria in costal waters and marine environments, especially in summer. Patients typically Hx liver disease/ hemochromatosis

Contamination: raw oysters and wound contamination

Question 3

Presentation of Vibreo vulnificus wounds contamination

Answer 3

Rapidly progressive (<12hrs) 
Necrotizing Fasciitis 
Hemorrhagic Bullous Lesions 
Septicemia 
Cellulitis

Question 4

Ddx Nec fasciitis from Vibro vs Staph/Step

Answer 4

VIBRO: RAPID

Staph/Step: More common but develops over days.

Question 5

Diagnosis Vibro Vulnificus

Answer 5

Blood & wound culture

Question 6

Tx Vibro Vulnificus

Answer 6

BNS: Empiric Abx (don’t wait for cultures)

IV ceftriaxone and doxycycline

Question 7

Presentation of anthrax

Answer 7

• Contact with animals/ animal hides
• Cutaneous ulcers
• Painless with necrotic depressed center
• Gram- positive culture

Inhalation causes fulminant pneumonia

Question 8

Lesions of Steven-johnson syndrome

Answer 8

Painful, often confluent, lesions that begin as laceless and progress to vesicles/ bullae.
Pts have flu like prodrome.

Question 9

Disgnosis: cancer patient with chemotherapy, 1 day fever and rash, contender macula’s, gangrenous ulcers

Answer 9

Ecthyma gangrenous

Question 10

Lesions of ecthyma gangrenosum

Answer 10

Rapidly progressing (12-18hrs). Cutaneous or mucous membrane lesions the begin as painless red macules and become indurates pustules/ bullae. Often with “punched-out” gangrenous ulcers

Question 11

Organisms that cause ecthyma gangrenosum

Answer 11

Most common: P. Aeru

Question 12

Mechanism of ecthyma gangrenosum

Answer 12

Immunocompromised patient with bacteremia/ sepsis. Organism invades the vascular media and adventitia, causing ischemic necrosis.

Question 13

S&S Hot Tub folliculitis

Answer 13

Within hours of few days of swimming 
Tender
Papules, Pustules or nodules 
Low grade fever
Self-limiting
Does not respond to TMP-SMX

Question 14

Tx pseudomonas aeruginosa folliculitis (hot tub folliculitis(

Answer 14

Self limiting. Avoid the source of contamination.

If persistent: oral fluoroquinolone

Question 15

S&S sporothrix schenckii

Answer 15

Hx gardening/ outdoor activity
Weeks to develop
Ulcerative initial papule
Lesions along proximal lymphatic chain

Question 16

Tx impetigo

Answer 16

Topical mupiocin (localized infection)
Oral Abx- cephalexin (wide spread)