fungal infections

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					                           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

				
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