fungal infections of the skin and nails

Fungal Infections of the Skin and Nails

Adam O. Goldstein, MD, MPH

Associate Professor

Department of Family Medicine

University of North Carolina at Chapel Hill

aog@med.unc.edu

Fungal Infections of the Skin and Nails

Objectives

1. To distinguish common fungal infections from similar appearing lesions; e.g. eczema

2. Improved dx of fungal lesions with a KOH scraping

3. Know at least 2 tx options for common fungal infections of the skin & nails

4. Know common errors in fungal dx and tx

5. Know when to suspect & how to dx ID reaction

Sorry… but ….

Superficial Fungal Infections

4.1 million visits -82% nondermatologists 3 types of fungi-dermatophytes: Epidermophyton

Trichophyton

Microsporum

Named by location Similar treatments; Varied presentations

If they do this to food…..

Superficial Fungal Infections

Common Denominator = Do KOH, Do KOH, Do KOH ..

Nondermatologists (34%) were more likely than dermatologists (5%) to prescribe combination products for the treatment of common fungal skin infections; savings = $10-25 million.

(Smith, JAAD,1998)

KOH

ID Reaction

Severe inflammatory skin reaction Immunologically mediated Appearance may be very different from

original lesion Fungal infections if severe enough may

provoke ID reaction. If you do not think about it, you will not diagnose it.

ID Reaction

Tinea capitis

Trichophyton or Microsporum species

Disease of children Exposure from other

children or pets Highly variable

presentation

T. capitis

Primary lesions: plaques, papules, pustules or nodules

Secondary lesions: scale, alopecia, erythema, exudate and edema

Kerion: Severe T. capitis- inflamed, boggy nodule with hair loss

Kerion

T. capitis

Diagnosis Overdiagnosed in adults,

underdiagnosed in children Direct microscopic exam of hairs

looking for hyphae/spores Woods lamp: bright green

fluorescence in hair shafts d/t Microsporum infection (< 20% time)

Culture: If KOH is negative but strong clinical suspicion

T. capitis

Differential Diagnosis Seborrheic dermatitis- rare in children, KOH - Cellulitis- may coexist, KOH - Alopecia areata-discrete, nonscaling areas

hair loss Syphilis- “mothball eaten” areas

The diagnosis please…..

T. capitis

Treatment Systemic therapy needed Griseofulvin at least 8 wks

(Or 2 wks beyond cure) Itraconazole- 3-5mg/kg/day

1x/week 3 weeks Fluconazole- 3-6 mg/kg children

(10, 40 ml) Terbinafine - 3-6mg/kg/day X 4

weeks

Griseofulvin

Microsize 250, 500 mg tabs, 125 mg/5 cc susp

500-1000 mg/day adults 15-20 mg/kg/day children SE’s: photosensitivity, H/A, GI

upset, hypersensitivity, leukopenia Active only against dermatophytes, not

yeasts

T. capitis

Patient education Compliance for 2 weeks beyond

“cure” to prevent relapse Look for sources of infections Clean contaminated objects Reassure caretakers that it may

take 1 month for improvement

Tinea barbae

Characteristics Inflammation in the

beard/hair Pseudofolliculitis Frequently “failed” antibiotics Positive S.Aureus culture does

not rule out T. barbae

T. barbae

Diagnosis Nodular, boggy lesions

with exudate

Sinus tract formation Scarring if untreated KOH or culture may

confirm

T. barbae

Differential diagnosis Bacterial folliculitis Pseudofolliculitis barbae Contact dermatitis Herpes Syphilis Acne Candida

T. barbae

Treatment Griseofulvin 0.5-1 g/day Itraconazole or terbinafine for resistant

cases Local care

Tinea corporis

Papules or plaques with erythema and scale Look for annular lesions with central clearing Well-demarcated edges

T. corporis

Diagnosis KOH from leading edge Prior steroid use alters

response/appearance Majocchi’s granuloma:

pluck hairs for hyphae

T. corporis vs. Majocchi’s granuloma

T. corporis

Differential diagnosis Nummular eczema KOH neg Pityriasis rosea KOH neg, multiple

papules/plaques Psoriasis KOH neg, thick, silvery

scales Granuloma annulare KOH neg, no scale

Lyme disease KOH neg, no scale

T. corporis: Differential diagnosis

The diagnosis please...

Lichen simplex chronicus Nummular eczema

T. corporis

Treatment Avoid “Lotrisone” type combos Topical agents for

mild/moderate disease Oral agents for

extensive/resistant disease Continue topical medication 7-

14 days beyond “cure”

Tinea cruris

Thrives in humid environments

Diagnosis: » Spares scrotum; » Pruritus & burning clues» Look for feet as possible

infection source» KOH + hyphae

T.crurisDifferential Diagnosis: Candida Beefy red with poorly defined

borders Intertrigo KOH negative, irritant

dermatitis Erythrasma Asymmetric velvety patches,

Neg KOH Psoriasis Thick silvery scales,Neg

KOH Seb derm Borders less defined,

distribution different, Neg KOH

T. cruris

Treatment Topical agents for 2-3

weeks Mild topical steroid for

inflammatory component Pruritus relief Look for infection source

T. cruris

Patient education Use topical meds 7-14 days beyond cure Avoid prolonged topical steroids Avoid self-medicating preps Avoid baths and tight fitting underwear Use mild soaps or soap substitute Antifungal powders Keep area dry

Tinea manus

Diagnosis: » Often unilateral, but

with bilateral feet» May have only scant

scaling, vesicles Differential Diagnosis:

Eczema, contact dermatitis Treatment: Topical agents

The diagnosis is ...

Tinea pedis

Diagnosis: – Extremely variable presentation– Be aware of id reaction and bacterial infection

T. pedis

Differential Diagnosis: Eczema, Contact, Psoriasis, Keratolysis

Treatment and Patient Education: Limited: Antifungal creams X 1-4 weeks; Severe: Oral therapy

Griseofulvin 500 mg microsize bid X 4-8 weeksTerbinafine 250 mg/day X 2-6 weeks

The diagnosis is …..

Tinea Versicolor

Diagnosis: macules, plaques; fine scale after scraping; KOH +

Tinea Versicolor

Treatment: Limited disease: Topical agents

Widespread: Ketoconazole

200 mg X 2 one dose, repeat 1 week

(Not griseofulvin) Prevention and Patient Education:

Selenium sulfide 2.5% overnight 1X/month

Candidiasis

Diagnosis: Beefy red lesions, satellite papules and pustules

Differential Dx: Tinea, Intertrigo

Treatment and Patient education : Topical antifungal creams

Oral therapy for extensive (not Griseofulvin)

Environmental: Zeasorb powder or Burow’s

Mild topical steroids

The diagnosis is...

Onychomycosis

Onychomycosis

Why should we treat? (cosmetically disfiguring, painful, entry for cellulitis)

Diff Dx: Psoriasis, Lichen Planus, Trauma

Diagnosing vs. treating

Diagnosis? Culture? Treatment?

CaseWhich of the following, if any, is

onychomycosis?

Onychomycosis- treatments

8% Ciclopirox (Penlac) Topical therapy: FDA approved (2/00)

2 studies X 48 weeks:219 5.5% cc 6.5% ac vs. .9% placebo235 8.5% cc 12% ac vs. .9% placebo

se: erythema 5%

1x/day for seven days, remove w/alcohol and begin again

Onychomycosis- systemic

Oral meds:

Terbinafine- 250 mg qd X 6 wks Fingernails;

X 12 wks Toenails

Itraconazole- 200 mg bid 1 wk/month

X 2-3 months Fingernails;

X 3-4 months Toenails

Fluconazole- 150-300 mg 1x/week x 6-9 months

Side effects: GI, Skin, H/A, LFT, Drugs

Onychomycosis- oral meds

RCT-DB, PC- 72 week f/u 496 patients Continuous terbinafine vs. pulsed itraconazole No diff. SE’s

T3 T4 I8 I4MC 76% 81% 38% 49%CC 54% 60% 32% 32%

(BMJ, 4/99, 318: 1031-1035)

Evidence-based reviews- Fungal

Pooled analysis trials comparing mycological cure rates

Continuous treatment with terbinafine (250 mg/d for 12 weeks) & continuous treatment with itraconazole (200 mg/d for 12 weeks)

Statistically significant difference in 1 year outcomes in favor of terbinafine (risk difference, -0.23 [95% confidence interval, -0.32 to -0.15]; number needed to treat, 5 [95% confidence interval, 4 to 8]).

(Crawford, Arch Dermatol, 2002)

Evidence-based review- Fungal

Oral treatments for T. Pedis Twelve trials, 700 participants 2 trials comparing terbinafine and griseofulvin A pooled risk difference of 52% (95% confidence

intervals 33% to 71%) in favor of terbinafine's ability to cure infection

(The Cochrane Library, 2003, http://www.update software.com/abstracts/ab003584.htm)

Summary

Do a KOH when possible or doubtful Avoid brand name combination

steroid/antifungal products Remember patient education strategies

Pearls

T. capitis- overdiagnosed in adults/under in children; oral therapy needed

T. cruris- spares scrotum T. manus- often unilateral T. Pedis- highly variable presentation T. versicolor- oral therapy effective Onychomycosis- oral meds needed

What’s the diff dx?

How to dx? Use combo

meds? How to tx?

Diff dx:» SCCa, Eczema, Tinea

How to dx: » KOH, KOH, KOH

Use combo meds: NO» wrong 30% » unclear length of time» more difficult for subsequent dx » $$$» potent steroids

Tx: Lidex 0.05% bid

A few unknowns

A few unknowns

A few unknowns

A few unknowns

Thank You …….