Duncanville Dermatology Clinic Dermatology Residency

Presentation on theme: "Duncanville Dermatology Clinic Dermatology Residency"— Presentation transcript:

1 Fungal Infection of the Skin November 24th , 2003 Michael Hohnadel D.O.
Duncanville Dermatology Clinic Dermatology Residency KCOM Dermatology Department

2 Topics Covered Basic diagnostic techniques
KOH Culture Woods light Tinea infections with special attention to scalp, feet and nails Tinea Versicolor Candidiasis Differentials to consider. Basic Treatment

3 Questions What is a Wood’s light useful for ?
If I think it might be a fungus but it is KOH negative, what can be done to prove it ? How do you know the endpoint of therapy when treating tinea capitis ? How do you know the endpoint of therapy when treating tinea versicolor ? If a patient has thick ugly nails, what is the chance that it is classic onychomycosis ?

4 Diagnostic Tests KOH Preparations Skin
Two slides or slide and #15 blade. Scrape border of lesion. Apply 1-2 drops of KOH and heat gently Examine at 10x and 40x Focus back and forth through depth of field. Look for hyphae Clear, Green Cross cell interfaces Branch, constant diameter. Chlorazol black, Parkers ink can help. Spaghetti meatball appearance is classical for yeast The most common pathogen for tinea capitus used to be microsporoum. It is now T. Tonsauran thus render wood’s light useless

5 Diagnostic Tests KOH Preparations Nails Hair Be Persistent !
Thin clipping, shaving or scraping Let dissolve in KOH for 6-24 hours. Can be difficult to visualize. Culture often required. Hair Directly examined without KOH. Apply KOH and heat hair until macerated Look for spores. Be Persistent !

6 Tinea Versicolor Trichophyton Tonsurans

7 Tinea Versicolor

8 Parkers Ink Stain

9 Watch out for Mosaic Fungus

10 Mosaic Fungus Lipid droplets in interepithelial spaces and cell membrane overlap simulate fungal hyphae.

11 Fungal Cultures Diagnostic Tests DTM (Dermatophyte Test Medium)
Yellow to red is (+). Nickerson’s Media Yeast Black growth is (+) Sabouraud’s Media Molds

12 Diagnostic Test: Fungal Culture Example of DTM

13 Diagostic Test Fungal Culture

14 Diagnostic Tests Fungal Culture Sample Collection
Scrape with blade or rub with cotton Q-tip. Nail clipping or curette. Implant in media. Cap Loosely, Fungi are aerobic Read at 2 weeks and 4 weeks.

15

16 Tinea Capitis

17 Diagnostic Tests Wood’s Light PAS stain of skin or nail clipping.
Tinea Capitis Blue green florescent with M. Canis. Not useful for Trichophyton (Most Common) Other Areas: Useful to diagnose as erythrasma (coral red/pink). Tinea versicolor may be pale white yellow. Less helpful if patient recently bathed. PAS stain of skin or nail clipping.

18 Woods Light – M. Canis

19 Woods Light - Erythrasma

20 Different Types of Infection
Dermatophyte Fungal Infection Tinea Capitis Tinea Pedis Tinea Unguium (Onychomycosis) Tinea Corporis Tinea Faciales Tinea Cruris Tinea Manuum Tinea Vesicolor Candidiasis

21 Tinea Capitis

22 Tinea Capitis Children most common cases. Most Common Organisms:
T. Tonsurans - acounts for 90% in U.S. M. Canis - seen in children with infected animals. Adults not infected. M. Audouinii - grey, broken shaft tinea

23 Tinea Capitis Presentations of Tinea Capitis
Non-inflammatory ‘black dot’ type Seborrheic type Pustular Inflammatory (Kerion)

24 Tinea Capitis Black Dot Type
Large Areas of Alopecia without inflammation Mild scaling Occipital adenopathy Black dot hairs. At first glance may look like Alopecia areata

25 Tinea Capitis

26 Tinea Capitis Seborrheic type Common– resembles dandruff
Close exam for broken hairs, black dots Adenopathy Frequently negative KOH (70%) Culture often necessary for DX

27 Tinea Capitis Kerion Inflamed, Boggy and tender.
M. Canis common etiology Systemic symptoms: Fever, Adenopathy. Scaring alopecia may occur KOH often negative May look bacterial

28 Tinea Capitis - Kerion

29 Tinea Capitis Pustular Discrete pustules and crusted areas
No significant hair loss or scale Often KOH negative Frequently treated as bacterial at first

30 Tinea Capitis Diagnosis
History Close contacts, pets, duration. Morphology of lesion Broken hairs, black dots, localized. Woods Lamp Blue green. Hair Shaft Exam Endo/Exothrix Culture Plucked Hair shafts, Q-tip or tooth brush.

31 Normal Hair

32 Tinea Capitis - Endothrix

33 Tinea Capitis - Exothrix
KOH and ‘Quick Ink’ M. Canis

34 Tinea Capitis Treatment
Must treat hair follicle Topical not effective Systemic agents Griseofulvin for children – liquid with good taste. Imidazoles, terbinafine. Steroids for inflamed lesions like Kerion. Treat until no visual evidence, culture (-)… plus 2 weeks Average of 6-12 weeks of treatment. Examine / treat family in recurrent cases.

35 Tinea Pedis and Manuum. T. Rubrum most common etiology
Dull erythema with pronounced scale. Leading edge of scale not as common. Two feet one hand involvement. T. Mentagrophytes causes inflammatory tinea pedis Vesicles and bullae.

36 General Morphology Tinea Pedis

37 Tinea Pedis

38 General Morphology Tinea Manuum

39 Two feet one hand

40 Tinea Pedis Groups: M > F. Young and middle aged.
Patient is susceptible to reoccurrence Onychomycosis and tinea pedis associated. Differential: Eczema, contact dermatitis Psoriasis. Erythrasma and Candida (esp in web spaces.) Pitted keratolysis

41 Tinea Pedis Diagnosis PE/History – onychomycosis, contacts, med cond.
KOH exam – Thick scale, no leading edge Woods Light - Helps to differentiate from erythrasma Culture Remember: ‘hand eczema’ may be a dermatophyte infection of hands or id reaction from tinea at another location.

42 Tinea Pedis: Treatment
Dry Feet Alternate shoes, Absorbent powders, Change socks Scale my be reduced with keratolytic SAL acid, Lactic acid, Carmol Topicals and/or Systemics. Topical: naftine, lamisil, mentax may be more effective than azoles. Steroids if inflamed. Systemic allyamines or azoles Treat secondary bacterial infections. Steroids for severe inflammation and ID.

43 General Morphology Onychomycosis
15-20% of those between yrs. infected. No Spontaneous remissions General Appearance: Typically begins at distal nail corner Thickening and opacification of the nail plate Nail bed hyperkeratosis Onycholysis Discoloration: white, yellow, brown Edge of the nail itself becomes severely eroded. Some or all nails may be infected Often accompanying tinea pedis

44 Onychomycosis 4 Types: Distal Subungal White superficial
T. Mentagrophytes and molds Chalky white patches Proximal Subungal May indicate HIV infection Candidaonychomycosis Normally hands with accompanying paronychia

45 Onychomycosis

46 Onychomycosis with Onycholysis

47 White Onychomycosis

48 Candidaisis of nail Paronychia

49 Onychomycosis Allergic contact (nail polish, food items) Psoriasis
Differential Diagnosis: (50% of ‘thick nails’ not classic fungus.) Allergic contact (nail polish, food items) Psoriasis Lichen Planus Molds Nail dystrophies (ex – nephrogenic) Drugs

50 Onycholysis from Contact Dermatitis to Artificial Nails

51 Psoriasis Middle of nail, oils spots, pitting.

52 Psoriasis

53 Lichen Planus

54 Onycholysis from wet - dry

55 Pseudomonas of nail

56 Terry nails ‘half and half’

57 Molds

58 Bowen’s disease of the Nail

59 Onychogryphosis Mostly nursing home patient with no nail care
Note the concurrent tinea pedis

60 Diagnosis of Onychomycosis
Try to identify fungi before oral therapy KOH of nail clipping May need some time to dissolve nail. Culture DTM - dermatophytes Sauborauds – Molds Nickerson – Yeast Nail clipping for histology and PAS staining if above is negative and clinical suspicion is high.

61 Curettes for Specimen Collection.

62 Treatment of Onychomycosis.
Debridement of infected area helps penetration / comfort. Mechanical Urea products (ex carmol) Topical Treatment: Can be effective for limited involvement and for prevention. Agents Penlac (every day for one year) Mycocide Nail solution

63 Treatment of Onychomycosis
Oral therapy Effective. Relapse rate % in one year. Lamisil 250mg. 6 weeks/12 weeks. Baseline labs and one month. CBC (neutropenia), Liver function. Itraconazole 200 mg /day. 6 weeks/12 weeks Baseline labs and one month. Similar to lamisil. Pulse dosing fingernails - (200 mg bid 1 wk q mo.) x 2 No lab monitoring needed

64 Treatment of Onychomycosis
Notes on Therapy Other Azoles require longer therapy. Nails will not appear clear at end of therapy Measurements and digital photography verify effectiveness. For you and for patient

65 General Morphology Tinea Corporis
Papulosquamous Erythematous Annular Scaling Crusting ‘Ringworm’

66 General Morphology Tinea Faciales

67 General Morphology Tinea Cruris

68 General Morphology Tinea Versicolor
Numerous, well-marginated, oval-to-round macules with a fine white scale when scraped. Pigmentary alteration uniform in each individual. Red Hypo pigmented Hyperpigmented Scattered over the trunk and neck. Seldom the face. Pityrosporum orbicularis, M. furfur Normal flora of skin Asymptomatic.

69 Tinea Versicolor More apparent in the summer.

70 Tinea Vesicolor Hyperpigmented Variety
Looks Like: intertrigo, erythrasma ….

71 Tinea Versicolor - Differential
Vitiligo Pityriasis Alba Pityriasis Rosea Nummular Eczema Psoriasis Idiopathic guttate hypomelanosis

72 Vitiligo White without scale.

73 Pityriasis Alba Frequently on face, KOH neg. Few lesions.
May have fine white scale.

74 Pityriasis Rosea Papules or plaques with Collarette of scale, KOH (-), Woods light neg. HX.

75 Guttate Psoriasis

76 Idiopathic guttate hypomelanosis
White, small, no scaly, age.

77 Tinea Versicolor Diagnosis: Scrape lightly – fine white scale
KOH Positive for short hyphae and spores (Spaghetti and meatballs) Woods Light – pale yellow white fluoresce. Culture rarely done.

78 Tinea Versicolor

79 Tinea Vesicolor – Woods Light
Yellow White

80 Tinea Versicolor Microscope

81 Tinea Versicolor-Treatment
Topicals for limited involvement. Selenium Sulfide Shampoos: lather 10 minutes wash off x 7 days. Ketoconazole 2% shampoo: 5 minutes 1-3 days. Imidazoles topicals to body qd-bid for 2-4 wks. Terbinafine spray.

82 Tinea Versicolor-Treatment
Oral for extensive Itraconazole, fluconazole, ketoconazole. Dosing varies: single dose to 5-10 days of therapy. Likes gastric ph for absorption. Avoid bathing with 12 hours of ingestion.

83 Tinea Versicolor-Treatment
Notes Hypopigmentation resolves slowly No scale when scraped indicates cure. Sunlight helps restore pigment Prophylaxis before summer in some patients. Selenium shampoo’s Q month orals

84 Candidiasis Candida Albicans Normal Flora
Occurs in moist areas especially where skin touches. Presentation: primary lesion is a red pustule. Most Common: pustules dissect horizontally through the stratum corneum leaving a red, glistening denuded surface with long continuous border with satellite lesions. May also present as an eruption of multiple pustules which become erythematous papules between skin folds.

85 Candidiasis Immunosuppression of any type (disease, steroids), D.M., Antibiotics or receptive environments predispose. Diagnosis: History of predisposing factors and/or classic appearance of lesions at typical locations. Red and glistening in intertriginous area esp in predisposed individual think candida.

86 Candidiasis

87 Candidiasis

88 Difficult to be sure in Web spaces.

89 Candidiasis Differential: Erythrasma – likes skin creases
Eczema – may look like pustular candida Bacterial folliculitis – as above Psoriasis – gluteal cleft Tinea – same locations

90 Candidiasis KOH for pseudohyphae and spores Woods Light
May be impossible to tell visually from tinea. Woods Light Culture. Nickersons (+) Remember yeast part of normal flora. Add up the evidence

91 Candidiasis

92 Treatment of Candidiasis
Keep dry – Z-sorb powder, cotton ball between toes. Topical – azoles. Occasionally co-administration of a weak topical steroid may be helpful. Diaper rash Angular chelitis. Treat co-existent bacterial infection if present.

93 THE END