superficial dermatophyte infections Flashcards
what are dermatophytes
general name given to fungi that cause skin diseases by invading keratin.
list the 3 types of dermatophytes and their site of infection q
microsporum - skin, hair epidermophyton -skin, nails trichophyton - skin, hair, ,nail
which form of dermatophyte transmission has worse presentation
zoophilic type is worse than person to person
diseases caused by dermatophytes
tinea pedis tinea if the hands tinea of the nails tinea corporis tinea of the groin tinea capitis
which is the most common site of fungal infection
tinea pedis
causative agent of tinea pedis
trichophyton rubrum is most common and difficult to eradicate
how is tinea pedis acquired
communall showers
swimming pools
occlusive footwear
what fungal infections are assoc w/ tinea pedis
2
tinea of the nail
(usually toenail)
tinea of the hands
presentation of toenail tinea
free edge is yellow and crumbly and thickened
nail seperates from its bed
usually affects one nail
what causes tinea of the fingernails
chronic skin infection of t rubrum on the hands
presentation of tinea of the hands
assymetrical
mild erythema which characteristic POWDERY SCALE ON CREASES
which tinea affects men>women
tinea of the groin
groin tinea presentation
assymetrical
unilateral
affects upper inner thigh
spares scrotum
describe the lesion in groin tinea
slowly expanding lesion
forms sharpdemarcations and peripheral scales
vesicles/ pustules
which fungal diseases doesn’t spare the groin
candidiasis
describe the lesion in tinea corporis
slowly expanding lesion with ring like pattern due to central healing
which demographic is at risk of tinea capitis
children
what is a kerion
inflammatory lesion w/ lymphadenopathy causing permanent hair loss
how is kerion acquired
zoophilic tinea capitis from cattle
describe the lesion seen in anthropophillic tinea capitis
minimal inflammation
scales
broken off hairs 3-4mm from scalp
dg
microscopic exm of scrapings/ clippings/ hair
wood light scalp exam for tinea capitis
how should scrapings be acuired
from the margin of the lesion with a scalpel
how are nail clippings acuired
from the crumbliest part of the nail
how are specimens prepared for microscopic observation
apply potassium hydroxide