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
Mostly nursing home patient with no nail care Note the concurrent tinea pedis
1. Fungal Infection of the Skin
Michael Hohnadel D.O.
2. Topics Covered
 Basic diagnostic techniques
– Woods light
 Tinea infections with special attention to scalp, feet and
 Tinea Versicolor
 Differentials to consider.
 Basic Treatment
1. What is a Wood’s light useful for ?
2. If I think it might be a fungus but it is KOH negative,
what can be done to prove it ?
3. How do you know the endpoint of therapy when
treating tinea capitis ?
4. How do you know the endpoint of therapy when
treating tinea versicolor ?
5. If a patient has thick ugly nails, what is the chance
that it is classic onychomycosis ?
4. Diagnostic Tests
– 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.
5. Diagnostic Tests
– Thin clipping, shaving or scraping
– Let dissolve in KOH for 6-24 hours.
– Can be difficult to visualize.
– Culture often required.
– Directly examined without KOH.
– Apply KOH and heat hair until macerated
– Look for spores.
 Be Persistent !
6. Tinea Versicolor
7. Tinea Versicolor
8. Parkers Ink Stain
9. Watch out for Mosaic Fungus
10. Mosaic Fungus
Lipid droplets in
spaces and cell
11. Diagnostic Tests
DTM (Dermatophyte Test Medium)
– Yellow to red is (+).
– Black growth is (+)
12. Diagnostic Test: Fungal Culture
Example of DTM
13. Diagostic Test Fungal Culture
14. Diagnostic Tests
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. Tinea Capitis
16. Diagnostic Tests
 Wood’s Light
– 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.
17. Woods Light – M. Canis
18. Woods Light - Erythrasma
19. Different Types of Infection
 Dermatophyte Fungal Infection
– Tinea Capitis
– Tinea Pedis
– Tinea Unguium (Onychomycosis)
– Tinea Corporis
– Tinea Faciales
– Tinea Cruris
– Tinea Manuum
 Tinea Vesicolor
20. Tinea Capitis
21. 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
22. Tinea Capitis
Presentations of Tinea Capitis
1. Non-inflammatory ‘black dot’ type
2. Seborrheic type
4. Inflammatory (Kerion)
23. Tinea Capitis
Black Dot Type
Large Areas of Alopecia without
Black dot hairs.
At first glance may look like Alopecia areata
24. Tinea Capitis
25. Tinea Capitis
Common– resembles dandruff
Close exam for broken hairs, black dots
Frequently negative KOH (70%)
Culture often necessary for DX
26. Tinea Capitis
Inflamed, Boggy and tender.
M. Canis common etiology
Systemic symptoms: Fever, Adenopathy.
Scaring alopecia may occur
KOH often negative
May look bacterial
27. Tinea Capitis - Kerion
28. Tinea Capitis
•Discrete pustules and crusted areas
•No significant hair loss or scale
•Often KOH negative
•Frequently treated as bacterial at first
29. Tinea Capitis Diagnosis
 Close contacts, pets, duration.
 Morphology of lesion
 Broken hairs, black dots, localized.
 Woods Lamp
 Blue green.
 Hair Shaft Exam
 Plucked Hair shafts, Q-tip or tooth brush.
30. Normal Hair
31. Tinea Capitis - Endothrix
32. Tinea Capitis - Exothrix
KOH and ‘Quick Ink’
33. Tinea Capitis Treatment
•Must treat hair follicle
•Topical not effective
•Griseofulvin for children – liquid with good taste.
•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.
34. Tinea Pedis and
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
•Vesicles and bullae.
35. General Morphology
36. Tinea Pedis
37. General Morphology
38. Two feet one hand
39. Tinea Pedis
•Groups: M > F. Young and middle aged.
•Patient is susceptible to reoccurrence
•Onychomycosis and tinea pedis associated.
•Eczema, contact dermatitis
•Erythrasma and Candida (esp in web spaces.)
40. Tinea Pedis Diagnosis
•PE/History – onychomycosis, contacts, med cond.
•KOH exam – Thick scale, no leading edge
•Woods Light - Helps to differentiate from erythrasma
•Remember: ‘hand eczema’ may be a
dermatophyte infection of hands or id reaction
from tinea at another location.
41. Tinea Pedis: Treatment
•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.
42. General Morphology
 15-20% of those between 40-60 yrs. infected.
 No Spontaneous remissions
 General Appearance:
– Typically begins at distal nail corner
– Thickening and opacification of the nail plate
– Nail bed hyperkeratosis
– Discoloration: white, yellow, brown
– Edge of the nail itself becomes severely eroded.
 Some or all nails may be infected
 Often accompanying tinea pedis
1. Distal Subungal
2. White superficial
 T. Mentagrophytes and molds
 Chalky white patches
3. Proximal Subungal
 May indicate HIV infection
 Normally hands with accompanying paronychia
45. Onychomycosis with Onycholysis
46. White Onychomycosis
47. Candidaisis of nail
Differential Diagnosis: (50% of ‘thick nails’ not classic fungus.)
•Allergic contact (nail polish, food items)
•Nail dystrophies (ex – nephrogenic)
49. Onycholysis from Contact
Dermatitis to Artificial Nails
Middle of nail, oils spots, pitting.
52. Lichen Planus
53. Onycholysis from wet - dry
54. Pseudomonas of nail
55. Terry nails ‘half and half’
57. Bowen’s disease of the Nail
59. Diagnosis of Onychomycosis
Try to identify fungi before oral therapy
1. KOH of nail clipping
• May need some time to dissolve nail.
• DTM - dermatophytes
• Sauborauds – Molds
• Nickerson – Yeast
3. Nail clipping for histology and PAS staining if above is
negative and clinical suspicion is high.
60. Curettes for Specimen Collection.
61. Treatment of Onychomycosis.
Debridement of infected area helps penetration / comfort.
• Urea products (ex carmol)
• Can be effective for limited involvement and for
• Penlac (every day for one year)
• Mycocide Nail solution
62. Treatment of Onychomycosis
•Effective. Relapse rate 15-20 % 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
63. Treatment of Onychomycosis
Notes on Therapy
• Other Azoles require longer therapy.
• Nails will not appear clear at end of
• Measurements and digital photography
• For you and for patient
64. General Morphology
65. General Morphology
66. General Morphology
67. General Morphology
 Numerous, well-marginated, oval-to-round
macules with a fine white scale when scraped.
 Pigmentary alteration uniform in each
– Hypo pigmented
 Scattered over the trunk and neck. Seldom the
 Pityrosporum orbicularis, M. furfur
– Normal flora of skin
72. Pityriasis Alba
Frequently on face,
KOH neg. Few
May have fine white
73. Pityriasis Rosea
scale, KOH (-),
74. Guttate Psoriasis
75. Idiopathic guttate hypomelanosis
76. Tinea Versicolor
•Scrape lightly – fine white scale
•KOH Positive for short hyphae and spores
(Spaghetti and meatballs)
•Woods Light – pale yellow white fluoresce.
•Culture rarely done.
77. Tinea Versicolor
78. Tinea Vesicolor – Woods Light
79. Tinea Versicolor Microscope
80. 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
•Imidazoles topicals to body qd-bid for 2-4
81. Tinea Versicolor-Treatment
Oral for extensive
•Dosing varies: single dose to 5-10 days of
•Likes gastric ph for absorption.
•Avoid bathing with 12 hours of ingestion.
•Hypopigmentation resolves slowly
•No scale when scraped indicates cure.
•Sunlight helps restore pigment
•Prophylaxis before summer in some patients.
•Q month orals
•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.
•Immunosuppression of any type (disease,
steroids), D.M., Antibiotics or receptive
•Diagnosis: History of predisposing factors
and/or classic appearance of lesions at typical
•Red and glistening in intertriginous area esp in
predisposed individual think candida.
87. Difficult to be sure in Web spaces.
1. Erythrasma – likes skin creases
2. Eczema – may look like pustular candida
3. Bacterial folliculitis – as above
4. Psoriasis – gluteal cleft
5. Tinea – same locations
•KOH for pseudohyphae and spores
•May be impossible to tell visually from tinea.
•Culture. Nickersons (+)
•Remember yeast part of normal flora.
•Add up the evidence
91. Treatment of Candidiasis
• Keep dry – Z-sorb powder, cotton ball between
• Topical – azoles.
• Occasionally co-administration of a weak topical
steroid may be helpful.
• Diaper rash
• Angular chelitis.
• Treat co-existent bacterial infection if present.