Common Pyodermas Bethany KH Lewis, MD MPH Clinical Assistant - - PowerPoint PPT Presentation

Common Pyodermas

Bethany KH Lewis, MD MPH Clinical Assistant Professor University of Utah Department of Dermatology

I HAVE NO CONFLICTS OF INTEREST TO DECLARE

Today’s agenda

• Skin microbiome review
• Clinical presentations of pyodermas

– Impetigo – Folliculitis – Cellulitis

• Treatment guidelines

Pyoderma

• “Pyo” – pus
• “Derma” – skin
• Pyoderma – skin infection forming pus, or

bacterial skin infection

• Primary causative agents: Staph aureus and

Strep pyogenes

Skin microbiome1,2

• One billion organisms per cm2 of skin
• Colonization starts at birth, diversifies w/ age
• Bacterial species vary by site

– Sebaceous/follicle – Propionibacterium, Staphylococcus – Body folds – Corynebacterium > Staphylococcus

• Inflammatory diseases have been a/w altered

microbiomes

– Atopic dermatitis, rosacea, acne

Homeostasis disruption pyodermas2

• 1. Balance between skin and microorganisms

– Environmental trauma

• i.e. shaving, wounds, other

– Underlying skin barrier issues

• i.e. atopic dermatitis

– Predisposing conditions

• i.e. immunosuppression, diabetes
• 2. Disturbance of microorganism milieu

– Staph aureus overgrowth

• i.e. homogenization 2/2 exposure

– Decrease in diversity

Superficial pyodermas are common4

• Impetigo 0.3%
• Cellulitis 2.2%

Classification of pyodermas

Folliculitis Impetigo Cellulitis

Bacterial Infections

Epidermis Impetigo Dermis Cellulitis Appendages Folliculitis

Slide modified from and courtesy of Scott Florell, MD

FOLLICULITIS

Not all folliculitis is bacterial folliculitis5

Majocchi’s granuloma DDX includes :

• “Hot tub” – Pseudomonas
• Herpes simplex
• T. rubrum, Candida,

Pityrosporum

• Drugs or occupational

– Topical or PO steroids, lithium – Chloracne

• Nutritional deficiency
• Eosinophilic

Eosinophilic folliculitis

Bacterial folliculitis5,7

Diagnosis

• Bacterial swab for Gram

stain and culture

• KOH to evaluate for yeast or

fungus

• HSV PCR or DFA

Treatment

• Anti-Staph medications:

– Topical antibiotics

• Clinda/erythromycin lotion
• r solution
• Mupirocin ointment

– Antimicrobial washes

• Benzoyl peroxide 10% wash

– If extensive involvement, 5-10 day course PO ABX

When the hair follicle is more extensively involved7

Furuncle/Carbuncle/Abscess

• Diagnosis:

– Try to differentiate from inflamed epidermoid cyst

• Treatment:

– Incision & drainage – Culture & sensitivity – Empiric TMP/SMX or doxycycline – Defined MSSA: dicloxacillin or cephalexin – Defined MRSA: TMPSMX

Compare & Contrast

Inflamed EIC Furuncle/Abscess

Decontamination procedures

• Intranasal mupirocin BID x 5 days
• Daily chlorhexidine washes vs. dilute bleach

baths

• Daily decontamination of personal items

Bacterial Infections

Epidermis Impetigo Dermis Cellulitis Appendages Folliculitis

Slide modified from and courtesy of Scott Florell, MD

IMPETIGO

Impetigo

• Superficial epidermal infection, predominantly

Staphylococcus

Impetigo

• Thin-walled vesicles/pustules, easily rupture &

crust with a “honey” color

• Exposed areas: face, hands, neck, extremities

Impetigo7

• Diagnosis:

– Consider a wound culture to differentiate Staph vs. Strep – Typically this is MSSA

• Treatment:

– Topical antibacterial

• Mupirocin

– +/- systemic antibiotic if:

• extensive involvement
• outbreak situation
• glomerulonephritis-

causing S. pyogenes strain

• 7 d. PO cephalexin or

dicloxacillin

Bacterial Infections

Epidermis Impetigo Dermis Cellulitis Appendages Folliculitis

Slide modified from and courtesy of Scott Florell, MD

CELLULITIS

Cellulitis

• Bacterial infection of dermis & subcutaneous

tissue

• Often occurs near areas of skin breakdown

– Risk factors:

• Venous stasis/edema
• Toe web infections
• Eczema
• Legs > digits > other exposed sites

Cellulitis

• Routine blood or wound cultures not routinely

recommended

• 5 days anti-Strep antibiotic for routine cases

Treatment guidelines for cellulitis7

• Mild: without focus of purulence

– PO peni/dicloxacillin, cephalosporin, clindamycin

• Moderate: with systemic signs of infection

– IV penicillin, ceftriaxone, cefazolin, clindamycin

• Severe: failed orals, immunocomp, sepsis

– Empiric vancomycin + piperacillin/tazobactam – Emergent C&S and possible debridement

References

1. Weyrich, LS et al. The skin microbiome: Associations between altered microbial communities and disease. Australasian Journal of Dermatology 2015; 56: 268-74. 2. Schommer, NN & Gallo, RL. Structure and function of the human skin microbiome. Trends in Microbiology 2013; 21(12). 3. Chen, YE & Tsao, H. The skin microbiome: current perspectives and future challenges. JAAD 2013; 69: 143-55. 4. Stulberg, DL, Penrod, MA, & Blatny, RA. Common bacterial skin infections. Am Fam Physician Jul 2002; 66(1): 119-125. 5. Luelmo-Aquilar, J & Santandreu, M. Folliculitis: recognition and management. Am J Clin Dermatol 2004; 5(5): 301-310. 6. Baron, EJ et al. A guide to the utilization of the microbiology laboratory for diagnosis of infectious diseases: 2013 recommendations by the Infectious Diseases Society of America (IDSA) and the American Society for Microbiology (ASM). CID 2013; 57: 485-8. 7. Stevens, DL et al. Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the Infectious Diseases Society of America. CID 2014; 59: 147-159. 8. Korownyk, C & Allan, GM. Evidence-based approach to abscess management. Can Fam Physician 2007; 53: 1680-84. 9. Bernard, P. Management of common bacterial infections of the skin. Curr Opin Infect Dis 2008; 21: 122-8. 10. Birnie, AJ et al. Interventions to reduce Staphylococcus aureus in the management of atopic eczema 2008. The Cochrane Collaboration, Issue 3.