2025 – PAGE 165 – DERMATOLOGY
TRICHOTILLOMANIA
Trichotillomania is a body-focused repetitive behavior in which patients pull out their hair. (This may be on a location other than the scalp.) Look for loss of hair in an irregular pattern (not a nice circle). Also, the irregularly shaped patches will contain incomplete hair loss in which you will see hair of differing lengths.
IMAGE: www.pbrlinks.com/TRICHOTILLOMANIA1
IMAGE: www.pbrlinks.com/TRICHOTILLOMANIA2
(DOUBLE TAKE) ESSENTIAL FATTY ACID DEFICIENCIES
Essential fatty acids include LINOLEIC ACID and alpha-linolenic acid. Deficiency results in alopecia, a scaly dermatitis, and thrombocytopenia. Treat with IV lipids.
MNEMONIC: Imagine a fish whose red SCALES are shaped like HAIRY PLATELETS. As the fish struggles to find food, it becomes SKINNIER and skinnier (malnourished) and the hairy platelets begin to fall off. What’s left is a SKINNY (fat-free), BALD, and THROMBOCYTOPENIC fish!
APLASIA CUTIS CONGENITA
In aplasia cutis congenita, there is a congenital absence of the skin in an area. It is usually in a single location (most often the scalp) but can be in multiple areas. After the lesion heals and scars, a BALD SPOT is left behind. Aplasia cutis can be associated with underlying spinal dysraphisms and underlying skull defects.
IMAGE: www.pbrlinks.com/APLASIACUTIS1
IMAGE: www.pbrlinks.com/APLASIACUTIS2
PEARLS: Look for the HAIR COLLAR SIGN. This is a hairless area with a collar of dense hair at the edges. If given a picture of a scalp with the hair collar sign, get an MRI.