1. Skin and Soft Tissue Kristine Krafts, M.D. June 6, 2008 Infections

2. Bad infections cellulitis necrotizing fasciitis necrotizing myositis Not-so-bad infections impetigo folliculitis furuncles and carbuncles abscess superficial fungal infections deeper fungal infections Skin and Soft Tissue Infections

3. BACTERIA Gram-positive Cocci Staphylococcus Streptococcus Rods Bacillus Clostridium Actinomyces Corynebacterium Listeria Gram-negative Cocci Neisseria Rods A sh*tload Weird mycobacterium spirochetes chlamydia rickettsiae mycoplasma

4. Bad infections cellulitis Skin and Soft Tissue Infections

5. Infection of skin with some extension into subcutaneous tissues Most common location: extremities Strep pyogenes, Staph aureus Rarely, Clostridium perfringens (bad) Cellulitis Things you must know

6. Venous/lymphatic compromise Diabetes Alcoholism Cellulitis Predisposing factors

7. Swelling, erythema, warmth Lymphangitis, tender lymphadenopathy Maybe ringworm or psoriasis Maybe systemic symptoms Cellulitis Symptoms

8. Cellulitis

10. Strep pyogenes Staph aureus Haemophilus influenzae Clostridium perfringens Cellulitis Cause

11. Erysipelas Clostridial cellulitis Nonclostridial anaerobic cellulitis Cellulitis Special forms of cellulitis

12. Erysipelas painful, bright red, swollen skin Streptococcus pyogenes kids, elderly legs, face Cellulitis Special forms of cellulitis

13. Erysipelas

14. Clostridial cellulitis Local trauma, surgery Gas in skin Need surgical exploration Cellulitis Special forms of cellulitis

15. Erysipelas Clostridial cellulitis Nonclostridial anaerobic cellulitis Diabetes Gas in skin Foul odor Need surgical exploration Cellulitis Special forms of cellulitis

16. Bad infections cellulitis necrotizing fasciitis Skin and Soft Tissue Infections

17. Infection of fascia and fat; may spare skin Follows trauma (often mild) Strep pyogenes Often fatal Necrotizing Fasciitis Things you must know

18. Necrotizing fasciitis

19. Diabetes-associated mixed flora feet → leg fascia Necrotizing Fasciitis Special forms of necrotizing fasciitis

20. Diabetes-associated Head and neck fasciitis after surgery or dental work Ludwig’s angina Necrotizing Fasciitis Special forms of necrotizing fasciitis

21. Ludwig’s angina

22. Diabetes-associated Head and neck fasciitis Fournier’s gangrene Extension into GI/urethral mucosa Aggressive Severe pain Necrotizing Fasciitis Special forms of necrotizing fasciitis

23. Fournier’s gangrene

25. Fournier’s gangrene after debridement

26. Unexplained, excruciating, increasing pain Erythema In 1-2 days: erythema darkens; bullae appear Fever, myalgias, anorexia, hypotension Necrotizing Fasciitis Symptoms

27. Early necrotizing fasciitis

28. Necrotizing fasciitis

29. Necrotizing fasciitis 9 days later

30. Necrotizing fasciitis 16 days later

31. Treat aggressively with repeated surgical debridement, antibiotics, fluid replacement Can spread to multiple organ systems High mortality Necrotizing Fasciitis Clinical course

32. Bad infections cellulitis necrotizing fasciitis necrotizing myositis Skin and Soft Tissue Infections

33. Uncommon infection of muscle Develops rapidly Clostridium Often fatal Necrotizing Myositis Things you must know

34. Clostridium perfringens Deep, penetrating injury Bowel surgery Post-abortion with retained placenta Clostridium septicum Non-traumatic May enter through GI Necrotizing Myositis Etiology

35. Organisms injected into tissue Tissue damage → anaerobic environment Necrosis starts within 36 hours Clostridial toxins cause damage theta toxin: vessel injury alpha toxin: heart injury, cell lysis Necrotizing Myositis Pathophysiology

36. Sudden, severe pain Bronze, then purple-red skin Bullae and crepitus (gas) Systemic signs Necrotizing Myositis Symptoms

37. Necrotizing myositis

39. Aggressive surgical debridement IV antibiotics Hyperbaric oxygen Fatal without early debridement Necrotizing Myositis Clinical course

40. Bad infections cellulitis necrotizing fasciitis necrotizing myositis Not-so-bad infections impetigo Skin and Soft Tissue Infections

41. Superficial vesicopustular skin infection Children Face, extremities S. pyogenes, S. aureus Impetigo Things you must know

42. Impetigo

44. Bad infections cellulitis necrotizing fasciitis necrotizing myositis Not-so-bad infections impetigo folliculitis Skin and Soft Tissue Infections

45. Infection localized to hair follicles Multiple small pustules S. aureus, Pseudomonas Can lead to furunculosis Folliculitis Things you must know

46. Folliculitis

48. Hot tub folliculitis

49. Bad infections cellulitis necrotizing fasciitis necrotizing myositis Not-so-bad infections impetigo folliculitis furuncles and carbuncles Skin and Soft Tissue Infections

50. Furuncle: infectious nodule around hair follicle Carbuncle: larger, subcutaneous abscess S. aureus Can be dangerous Furuncles and Carbuncles Things you must know

51. “The bourgeoisie shall remember my boils!”

52. Furuncle

53. Carbuncles

54. Carbuncle

55. Bad infections cellulitis necrotizing fasciitis necrotizing myositis Not-so-bad infections impetigo folliculitis furuncles and carbuncles abscess Skin and Soft Tissue Infections

56. Localized infection of dermis, subcutaneum Arises from trauma, IV drug abuse S. aureus Bacteremia and distant infection can occur Abscess Things you must know

57. Staphylococcal abscess

59. Splinter hemorrhages in bacterial endocarditis

60. Bad infections cellulitis necrotizing fasciitis necrotizing myositis Not-so-bad infections impetigo folliculitis furuncles and carbuncles abscess superficial fungal infections Skin and Soft Tissue Infections

61. Slow-growing “Ringworm” Sharp margins Dermatophytes Dermatophytoses Things you must know

62. Dermatophytes = molds that invade skin, other keratinized tissues Sources: humans, animals, soil Three genera microsporum trichophyton epidermophyton Dermatophytoses

63. Microsporum

64. Microsporum and trichophyton

65. Calcofluor white stain (Candida)

66. Most classified by location Hair: tinea capitis, barbae Skin: pedis, cruris, corporis Nails: unguium Some other unique types Tinea nigra Piedra Dermatophytoses

67. Tinea corporis

70. Tinea cruris

71. Tinea pedis

72. Tinea nigra

75. Black piedra

76. White piedra

77. Pink to yellow-brown macules on trunk/arms Hypo-/hyperpigmentation, scaling Malassezia furfur “Spaghetti and meatballs” Tinea (Pityriasis) Versicolor Things you must know

78. Tinea (pityriasis) versicolor

81. Malassezia furfur

82. Bad infections cellulitis necrotizing fasciitis necrotizing myositis Not-so-bad infections impetigo folliculitis furuncles and carbuncles abscess superficial fungal infections deeper fungal infections Skin and Soft Tissue Infections

83. “Rose gardener’s disease” First: painless papule (hand) Then: open sore, lymphatic spread (nodules) Sporothrix shenckii Sporotrichosis Things you must know

84. Sporotrichosis

87. Tropical disease Swelling, nodules, pus with “grains” “Madura foot” Fungi (many) or Nocardia Mycetoma Things you must know

88. Mycetoma

89. Mycetoma granules

90. Granule histology: tons of hyphae

91. Bad infections cellulitis necrotizing fasciitis necrotizing myositis Not-so-bad infections impetigo folliculitis furuncles and carbuncles abscess superficial fungal infections deeper fungal infections Skin and Soft Tissue Infections