cutaneous fungal infections Flashcards
what are fungal infections?
Fungal skin infections, also known as tinea corporis or ringworm, are dermatophyte infections of the superficial layers of the skin. Dermatophyte infections of the groin are also called tinea cruris.
who is most likely to get tinea corporis?
children and young adults in warm, humid climates
who is most likely to get tinea cruris?
adolescent and adult males.
what causes cutaneous fungal infections?
Cutaneous fungal infections are most commonly caused by dermatophytes, which are a group of fungi which thrive in keratin, a substance found on many surfaces of the body, including the skin.
what causes tinea corporis?
dermatophytes Trichophyton rubrum and Trichophyton interdigitale
what causes tinea cruris?
caused by autoinoculation with these organisms but may rarely be caused by Epidermophyton floccosum
how do cutaneous fungal infections spread?
Direct contact with an infected person or animal
Indirect contact with fomites, for example shared towels
More rarely, contact with soil
RF for cutaneous fungal infections?
Exposure to infection
Local immunosuppression, for example use of topical corticosteroids
Systemic immunosuppression, for example oral corticosteroids or HIV infection
Diabetes mellitus
Obesity
Optimal conditions for fungal growth, including occlusive clothing, hyperhidrosis and warm humid climates
features of cutaneous fungal infections?
Patchy skin lesions which may be red or pink edge surrounding an area of central clearing and grow outwards
Patients may report the lesions becoming scaly or itchy
Lesions are most commonly found in skin folds, including the groin
when is it harder to diagnose cutaneous fungal infections?
If a person has previously been treated with topical corticosteroids, the lesions may have differing morphology and be much harder to diagnose.
what is conservative mx for cutaneous fungal infections?
Wearing loose-fitting clothing to minimise humidity around the skin
Regular washing and fully drying skin
Not sharing towels to reduce risk of spread
Washing clothing and linen regularly
what is medical mx for cutaneous fungal infections?
For mild disease topical antifungals should suffice, for example topical terbinafine or an imidazole creams.
If there is significant inflammation, a topical corticosteroid may be used for up to seven days.
For severe or widespread disease oral terbinafine is usually used first-line. Alternatives include oral itraconazole or griseofulvin.
when should a patient referred to dermatologist?
Referral to a dermatologist may be required for severe or refractory disease, diagnostic uncertainty or the person is immunocompromised.
who should not get terbafine for fungal infections>?
It is important to note that terbinafine should not be used in people with hepatic impairment - liver function tests should be checked prior to treatment and after 4-6 weeks. It should also be used with caution in those with renal impairment, autoimmunity or psoriasis.
complications of cutaneous fungal infections?
Secondary bacterial infections
Spread to the dermis and subcutaneous layers of the skin via the hair follicles, known as Majocchi granuloma
Spread to the hands due to scratching, known as tinea manuum
Tinea incognito, which occurs when a tinea infection is mistakenly treated with steroids, causing lesions with differing morphology and less inflammation which are much harder to diagnose.
