Superficial fungal infections


Superficial fungal infections are benign infections of the skin, scalp and nails caused by Candida albicans or dermatophytes.

Clinical features and treatment

Candidiasis

Candidal diaper dermatitis

Erythema of the perianal area with peripheral desquamation and sometimes pustules. Secondary infection may develop.

– Buttocks must be kept clean (ordinary soap and water) and dry.
– Avoid humidity: according to the context, expose the buttocks to air or change diapers more frequently; remove plastic pants.
– Protect the skin with zinc oxide ointment if diarrhoea is present.
– If diaper dermatitis is severe and persistent despite these measures, consider an intestinal infection (nystatin PO: 100 000 IU 4 times daily for 20 days).

Other candidiasis

– Candidiasis of skin folds: miconazole 2% cream, one application 2 times daily for 2 to 4 weeks
– Oral candidiasis: see Stomatitis, Chapter 3.
– Vulvovaginal candidiasis: see Abnormal vaginal discharge, Chapter 9.

Dermatophytoses

Dermatophytes cause various clinical lesions, depending on the anatomic site involved: scalp, glabrous (hairless) skin, folds or nails.

Anatomic site1

Clinical features

Treatment

Scalp
Scalp ringworm
Tinea capitis

Common in children. Depending on the species:
• One or more round, scaly, erythematous plaques with the ends of broken hairs.
• Inflammation, suppuration, crusting and peripheral lymphadenopathy (kerion).
• Permanent hair loss (favus).

Some scalp ringworms are contagious:
simultaneously examine (and treat) symptomatic contacts.

• Shave or cut hair short on and around the lesions.

• Local treatment: 2 times daily, clean with soap and water, dry and apply miconazole 2% cream or Whitfield’s ointment for 2 weeks or longer if necessary.

• Administer systemic treatment as local treatment alone does not cure scalp ringworm:
griseofulvin PO for 6 weeks minimum (up to 8 to 12 weeks)
Children 1 to 12 years: 10 to 20 mg/kg once daily (max. 500 mg daily)
Children ≥ 12 years and adults: 500 mg to 1 g once daily, depending on severity
or itraconazole PO
Children: 3 to 5 mg/kg once daily for 4 to 6 weeks (max. 200 mg daily)
Adults: 200 mg once daily for 2 to 4 weeks

• Suppurative lesions: treat superinfection (see Impetigo) before applying local antifungal treatment.

• For painful kerion: paracetamol PO.

In pregnant lactating/breastfeeding women: oral antifungals are contraindicated. Apply a topical treatment (miconazole 2% cream or Whitfield’s ointment) to limit the spread of infection until it is possible to treat orally.

Glabrous skin
Ringworm of the body
Tinea corporis

Erythematous, scaly, pruritic macule with a well-demarcated, raised, vesicular border and central healing.

• For non widespread, localised tinea:
Local treatment: 2 times daily, clean with soap and water, dry and apply miconazole 2% cream or Whitfield’s ointment for 2 to 4 weeks or for 2 weeks after clinical resolution.

• Reserve oral antifungals for particularly extensive lesions: griseofulvin PO for 4 to 6 weeks or itraconazole for 2 weeks.

Folds
Tinea pedis (athlete’s foot)
Tinea cruris

Interdigital spaces (Tinea pedis):
Pruritus, fissure and whitish scales in the 3rd and/or 4th interdigital spaces2 .

Groin (Tinea cruris):
Circumscribed, pruritic, erythematous plaque, with a pale centre surrounded by vesiculo- pustules, extending outward from the groin.

Topical treatment as above. If oozing lesions, use miconazole 2% cream only (do not use Whitfield’s ointment).




Footnotes
Ref Notes
1

Dermatophytosis may affect the nails (Tinea unguium, onychomycosis). Treatment is prolonged (12 to 18 months with griseofulvin) thus, in practice, difficult. Failures and relapses are frequent.

2 In candidal intertrigo, lesions are usually located in the 1st and 2nd interdigital spaces.