Fungal infections

Question 1

pityriasisversicolor
1/ What is it?
2/

Answer 1

1/ Rash, not commonly itchy caused by yeast Malassezia which is a commensal
–> The yeast produces azelaic acid, which diffuses down and impairs the function of themelanocytes.

2/ Treat with fluconazole or topical treatments
Terbinafine is not effective

(Ref Dermnet nz) 
Mild: 
Topical azole cream/shampoo (econazole, ketoconazole)
Selenium sulfide
Terbinafine gel 
Ciclopirox cream/solution
Propylene glycol solution
Sodium thiosulphate solution

The medicine should be applied widely to all the affected areas before bedtime for as long as directed (usually between 3 days and about two weeks, depending on extent of the rash).

Oral antifungal agents, itraconazole and fluconazole, are used to treat pityriasis versicolor when extensive or if topical agents have failed.

Oral terbinafine, an antifungal agent used to treat dermatophyte infections, is not effective for malassezia infections such as pityriasis versicolor.

Question 2

DDx for pityriasisversicolor

Answer 2

Discoid eczema 
Guttate psoriasis 
Pityriasis alba 
Pityriasis rosea 
Seborrhoeic dermatitis 
Tinea Corporis 
Vitiligo