Fungal infections
Cutaneous: dermatophytes, pityriasis versicolor, candidiasis.
Subcutaneous: mycetoma
Systemic: histoplasmosis, candidiasis, aspergillosis
Dermatophytes=ringworm=tinea
• 3 genera: trichophton, microsporum, epidermophyton.
• All give similar clinical picture.
• Invade keratin only.
• Zoophilic and anthropophilic.
• Clinical features depend on the site
Tinea pedis
* predisposing factors: swimming pools, occlusive footwear.
* Clinically:
interdigital scaling
or
Diffuse scaling of sole
or
Recurrent vesicles of the sole
Tinea unguium
• Toe nail more common than finger nail
• Free edge becomes yellow or whitish, the infection then spread
proximally with darkening of the nail plat and thickening of the nail
plate and subungual hyperkeratosis
Tinea corporis
• Erythematous scaly plaque, grow peripherally and clear centrally
annular configuration
• =active border
• Close inspection ----- vesicles and pustules
Tinea cruris
• Affects inguinal fold
• Erythematous plaque, scale, active border, not affects scrotum. close
inspection -----vesicles and pustules
• Differential diagnosis:
*Flexural psoriasis: look for other sites of predilection of psoriasis
*candidiasis: satellite papules, pustules
*seborrheic dermatitis: look for other sites of predilection of psoriasis
Tinea faciei
• Erythematous annular plaque- face
• Diff. diag.:
* seborrheic derm.: nasolabial, eyebrows, eyelashes, ears
* Rosacea: bilateral erythema, telangiectasia
Tinea capitis
• Patch of hair loss, scales, easily epilated hair.
• Usually children
• Zoophilic spp.: Intense inflamm., boggy swelling, pustules = kerion
• Diff. diag.:
alopecia areata: no inflamm.
trichotillomania: psych. upset, broken hair
Investigations
• Skin scraping, nail clipping, hair plucking + KOH
• Culture on sabouraud’s dextrose agar
• wood’s light ----- green fluorescence in some cases of T. capitis
Treatment
• Topical imidazoles ex. Clotrimazole, miconazole, econazole ----- Few
patches of T corporis, facei, cruris and pedis.
• Systemic therapy ex. Griseofulvin, terbinafine, imidazoles ex.
Fluconazole, ketoconazole, itraconazole ------Tinea capitis, T.
unguium, T.incognito, wide spread T. corporis, pedis and feciei
Candidiasis
• Opportunistic inf.
• Predisposing: age extremes, D.M, low immunity, ill fitted denture,
obesity, antibiotics, pregnancy, and malignancy.
• Oral thrush: whitish patches, its removal reveal erythematous base
• Angular stomatitis: whitish patches, soreness
• Intertrigo: (inguinal, axilla, under the breasts) erythematous patches,
satellite papules and pustules
• Erosio interdigitale: eroded patch affects the webs
Investigations
• Swab or scrapping for microscope exam yeasts
• Culture
Treatment
● Correction of underlying pred. factor
● Topical azoles
● Nystatin or amphotericin
● Fluconazole, itraconazole
Pityriasis versicolor
• Affects young adults, hot humid climate
• Pityrosporum orbiculare, Keratinophilic and lipophilic.
• Brownish or hypopigmented round patches, with fine scales
• Upper trunk, upper arms, neck.
• Tend to recur.
Investigations
• Usually it is a clinical diagnosis
• Scrapping.
• Wood’s light -----
lemon yellow
Treatment
• Topical: azoles: *ketoconazole shampoo
* other azole creams
selenium sulphide shampoo
● Systemic : fluconazole, ketoconazole,
itraconazole