Fungal and parasitic skin infection Flashcards
What are some examples of fungal skin infection?
- Candidiasis
- Tinea (Dermatophytoses)
- Pityriasis (Tinea) versicolor
- Emboli (e.g. aspergillus, mucor sp)
What is the common name for dermatophyte infection?
Ringworm
What is a dermatophyte infection of the scalp called?
Tinea capitis
What is a dermatophyte infection of the beard called?
Tinea barbae
What is a dermatophyte infection of the body called?
Tinea corporis
What is a dermatophyte infection of the hand called?
Tinea manuum
What is a dermatophyte infection of the nail called?
Tinea unguium
What is a dermatophyte infection of the groin called?
Tinea cruris
What is a dermatophyte infection of the foot called?
Tinea pedis (Athletes foot)
What are the 3 places from which dermatophyte fungi can be picked up?
Other humans (Anthropophilic fungi)
Animals (Zoophilic fungi)
Soil (Geophilic fungi)
How do dermatophytes infect the skin?
The fungus enters the skin via abraded or soggy skin and its hyphae spread in the stratum corneum
This infects keratinised tissues only such as skin, hair and nails
Describe the presentation of dermatophyte infection
There is an increased turnover of the epidermis, causing scaling and an inflammatory response, with invasion of hair follicles
The lesions grows outwards and heals in the centre, giving it a ring appearance
Who is most commonly affected by dermatophyte infection?
Males
Tinea capitis (Children)
What are the 3 most common forms of dermatophytes?
- Trichophyton rubrum (>70% of cases)
- Trichophyton mentagraphytes
- Microsporum canis (Cats and dogs)
How is diagnosis of dermatophyte infection made?
Diagnosis is made based on clinical appearance, woods light (Fluorescence) and scrapings of skin, nail or hair
These scrapings are sent to the laboratory in a Dermapak for microscopy and cultures, which takes around 2 weeks
How are small areas of dermatophyte infection treated?
Clotrimazole cream and topical nail paint (e.g. amorolfine)
How is tines capitis usually managed?
Terbinafine or itraconazole orally
What is intertrigo?
Inflammation caused by friction
Where does candida on the skin usually grow?
In skin folds where it is warm and moist, often in areas of intertrigo (Candida intertrigo)
- Under breasts
- Groin areas
- Abdominal skin folds
- Nappy areas
How is candida skin infection managed?
Clotrimazole cream or oral fluconazole
What are some examples of parasitic skin infestation?
- Scabies
- Lice
- Leishmaniasis
- Schistosomiasis
- Onchocerciasis
- Strongyloiidiasis
- Gnathostomiasis
- Amoebiasis
- Trypanosomiasis
- Hookworm
- Filariasis
- Acanthamoebiasis
What is scabies?
Scabies is a parasitic skin infection caused by Sarcoptes scabiei
What parasite is involved in scabies?
Sarcoptes scabiei
What is the incubation period of scabies?
Up to 6 weeks
How will scabies usually present?
It presents as an intensely itchy rash, affecting the finger webs, wrists and genital areas
The parasite can burrow into the skin causing burrows skin lesions
What is Norwegian scabies?
A chronic crusted form of scabies which is highly infectious
How is scabies managed?
- Malathion lotion - Applied overnight to whole body and washed off the next day
- Benzyl benzoate (Avoid in children)
Where lice species is usually involved in head lice?
Pediculus humanus capitis
What lice species is involved in body lice?
Pediculus humanus corporis
What lice species is involved in pubic lice?
Phthirus pubis
What is the main treatment of lice?
Malathion or dimeticone (Hedrin)
