Fungal Infections Flashcards
What commonly causes fungal infections on the skin, hair and nails?
Dermatophytes, yeast (Candida, Malassezia)
How are fungal infections spread?
Direct contact from other people, animals, soil and from formites
What are the most common genres of dermatophytes?
Trichophyton, Microsporum, Epidermophyton
What parts do fungus target?
Stratum corner of epidermis and nail keratin
Where does tinea pedis most commonly occur?
Between the toes (can spread to instep or sole)
What is the recommended frequency and duration for treatment of tinea pedis/cruris/corporis?
OD-BD, 2-6 weeks + ≥1 week after sx resolved
How many days should combination of antifungal and corticosteroid be used for?
7-10 days, then use antifungal alone
Why does tinea capitis require systemic treatment?
Dermatophytes are found at the hair follicle root, which is not accessible by topical treatments
Adjunctive tinea capitis treatment? and duration
Selenium sulfide (1-2.5%), ketoconazole (2%), povidone iodine for the first 2 weeks
Is oral or topical treatment better for onychomycosis? Why?
Oral (systemic)
Topical penetrate poorly to the nail bed
What is monotherapy of topical lacquers most suitable for?
Distal subungual onychomycosis affecting <50% of nail without involvement of lunula, white superficial onychomycosis and when less than 3 nails are affected
How often should you apply clotrimazole powder? Can it be used as main treatment?
BD-TDS, continue for 2 weeks after disappearance of symptoms
Only used as adjunct to cream or prophylactic in preventing new or recurrent infection (not rubbed into skin -> less effective)
Administration and frequency of nystatin suspension?
Swish and swallow QDS, up to 14 days
Nystatin is a P+ drug. What are the requirements and maximum dose and duration?
Indication: treatment of oral candidiasis
Minimum age: 6 months
Maximum daily dose:
· Infants and children 6 months and older: 400,000 units
· Adults: 2.4 million units
Maximum supply: 2 weeks
Frequency of topical itraconazole, ketoconazole, clotrimazole, miconazole, sertaconazole?
Itraconazole: OD
Ketoconazole: OD
Clotrimazole: BD (powder: BD-TDS)
Miconazole: BD-TDS (powder: BD but OD if used with cream; oral gel QDS)
Sertaconazole: OD-BD