Content

»	Bacterial Infections
	»	Gram-positive Infections
		»	Staphylococcal Infections
			»	Impetigo
			»	Staphylococcal Scalded Skin Syndrome (SSSS)
			»	Toxic Shock Syndrome (TSS)
			»	Bacterial Folliculitis
			»	Furuncle, Carbuncle, Abscess
		»	Streptococcal Infections
			»	Cellulitis
			»	Erysipelas (St. Anthony’s Fire)
			»	Blistering Distal Dactylitis
			»	Necrotizing Fasciitis
			»	Perianal Streptococcal Disease
			»	Ecthyma
			»	Scarlet Fever
			»	Streptococcal Toxic Shock Syndrome (STSS)
		»	Corynebacterial Infections
			»	Erythrasma
			»	Trichomycosis Axillaris
			»	Pitted Keratolysis
			»	Cutaneous Diphtheria
		»	Other gram-positive Infections
			»	Anthrax (Malignant Pustule)
			»	Erysipeloid (Fish Handler’s Disease)
			»	Actinomycosis (“Lumpy Jaw”)
			»	Actinomycetoma (Madura Foot)
	»	Gram-negative Infections
		»	Pseudomonal Infections
			»	Green Nail Syndrome
			»	Ecthyma Gangrenosum
			»	Pseudomonas Hot Foot Syndrome
			»	Pseudomonal Folliculitis (Hot Tub Folliculitis)
			»	Pseudomonal Pyoderma
		»	Other gram-negative Infections
			»	Acute Meningococcemia
			»	Bartonella Infections
			»	Rickettsiae
			»	Spirochetes
			»	Syphilis (Lues, Venereal Syphilis)
	»	Mycobacteria
		»	Tuberculosis (TB)
		»	Leprosy (Hansen’s Disease)
		»	Atypical Mycobacteria
			»	M. marinum (Fish Tank Granuloma)
			»	M. ulcerans (Buruli Ulcer)
			»	M. fortuitum Complex
			»	M. avium -Intracellulare Complex (M. avium Complex, MAI)
			»	M. kansasii

Bacterial Infections

GRAM-POSITIVE INFECTIONS
STAPHYLOCOCCAL INFECTIONS

S.aureus: aerobic, gram-positive catalase-positive bacteria arranged in clusters
Best defense: intact skin
MRSA: ↑ resistance to methicillin caused by staphylococcal chromosome cassettemec (SCC mec), specifically mecAgene (encodes alternative penicillin-binding protein, PBP2a)
Select S.aureus toxins:

	Toxic shock syndrome toxin-1 (TSST-1)		Superantigen, involved in toxic shock syndrome (TSS)
	Exfoliative toxin (ET-A, ET-B)		Protease activity, splits epidermal desmoglein 1, involved in staphylococcal scalded skin syndrome (SSSS) and bullous impetigo
	Panton–Valentine leukocidin (PVL)		In many community-acquired MRSA strains, associated with ↑ virulence (leukocyte destruction, necrosis)

Figure 4.7
A: Impetigo
(Courtesy of Dr. Paul Getz)
B: Bullous impetigo, arm
C: SSSS
(Reprint from Allen HB.
Dermatology Terminology.
New York, NY: Springer; 2010)