Hair & Nails Flashcards
Half and half nails
Chronic renal disease (also called Lindsay’s nails)
Proximal 1/2 with white zone, distal 1/2 with red brown zone
Nail finding in kidney disease
Half and half nails (Lindsay’s nails), proximal 1/2 with white zone, distal 1/2 with red brown zone
Proximal 1/2 with white zone, distal 1/2 with red/brown zone
1/2 and 1/2 nails (Lindsay’s nails) - found in renal disease
Beaded appearance of hair due to periodic thinning of hair shaft (like necklace with string of beads)
Normal at birth, develops in a few months with short fragile brittle hair
Monilethrix
Large uneven bubbles in hair due to trauma
Bubble hair
Bamboo hair
Trichorrhexis invaginata
Two paint brushes against each other (incomplete fracture with frayed ends), seen in which diseases?
Trichorrhexis nodosa
*Seen in Nethertons, Menkes disease, TTD, arginosuccinic aciduria
Name the hair finding found in Nethertons, Menkes, TTD, and arginosuccinase deficiency?
Trichorrhexis nodosa
Trichorrhexis Nodosa found in what disease(s)?
Menkes
TTD
Netherton
Arginosuccinase deficiency
Alternating light and dark bands under polarizing light
Trichothiodistrophy (due to sulfur deficiency), found in TTD duh
Twisting and flattening of the hair fiber
Pili torti
Pili torti found in what disorders
Bjornstad, Crandall Syndrome, Menkes, Netherton
Clean transverse fracture of hair shaft, mechanical or aquired
Trichoscisis
What disease is trichoscisis found in?
TTD
Name the hair findings in Trichothiodystrophy
Trichoscisis
Trichorrhexis nodosa
Name the hair findings in Menkes
Pili torti (most common) Trichorrhexis nodosa
Pili torti Trichorrhexis nodosa Short brittle "steel wool" hair Cupid's bow upper lip Torturous arteries Progressive CNS deterioration
Menkes Disease, due to defect in copper transporter
Pili trianguli et canaliculi
Uncombable Hair syndrome
Spun glass hair
Uncombable hair syndrome
Triangular cross-section with central linear groove along one side
Pili trianguli et canaliculi (seen in uncombable hair syndrome)
Spun glass hair (Pili trianguli et canaliculi) is due to premature keratinization of what part of the hair follicle?
Inner root sheath
Which part of the hair is derived from the mesoderm?
Dermal papilla
The infundibulum of the hair extends from the surface of the epidermis Down to which structure?
Opening of sebaceous gland
The isthmus extends from the opening of the sebaceous gland Down to what structure?
Insertion of arrector pili muscle (bulge)
Where is the bulge located in the hair follicle?
At the junction of the isthmus and the inferior segment. It is where the arrector pili muscle inserts
The outer root sheath occurs where in the hair follicle?
EVERYWHERE! It’s just that going up during the isthmus it will undergo trichilemmal differentiation, and then in the infundibulum is essentially keratinized like the rest of the epidermis
The inner root sheath is found in what part of the hair follicle?
Starts in the dermal papilla but disintegrates by the time it reaches the bulge which is in the isthmus
Which portion of the hair follicle is the inner root sheath never present?
The infundibulum
How long is anagen phase for each hair?
2-6 years
In which phase of the cell cycle are hairs located higher up in the epidermis?
Telogen
Causes of:
Dorsal pterygium
Ventral pterygium
Dorsal pterygium: lichen planks
Ventral pterygium: systemic sclerosis
Lichen planus nail findings: ventral or dorsal pterygium
Dorsal!
*ventral pterygium is cause by systemic sclerosis
Alternative treatment for LPP
Pioglitazone
Pioglitazone can be used to treat which hair disorder
LPP
Name a few scaring neutrophilic hairloss conditions
Dissecting cellulitis of the scalp
Folliculitis decalvans
Name a few lymphocytic scaring hairloss disorders
LPP (which includes frontal fibrosing alopecia, graham little syndrome)
CCCA
DLE
Pseudopalade of broq
Alopecia mucinosa
Keratosis follicularis spinularis decalvans
Which hairloss starts in the vertex scalp then spreads outwards, usually due to traumatic treatments
CCCA
How can you tell the difference between LPP and DLE on biopsy?
There will be no interface dermatitis seen at the DEJ in LPP! VS present in DLE
How can you tell the difference between LPP and CCCA on biopsy?
The lymphocytic infiltrate will Be WAY more intense in LPP (bc CCCA is just from hair products
What enzyme catalyzes the conversion of testosterone to DHT
5 alpha reductase
What does 5-alpha reductase catalyze the conversion of?
Testosterone to DHT
Where is type II 5 alpha reductase found?
Prostate mainly, but also the INNER ROOT SHEATH of the hair!
Where is
- type I alpha reductase found?
- type II 5 alpha reductase found?
- skin, hair follicles, and sebaceous glands
- type II found mostly in the prostate, but also in INNER root sheath of hair!
Which type if 5 alpha reductase is found in the inner root sheath of the hair?
Type II!!! Typically you think of type I only in the hair skin and nails and type II only in the prostate, but actually type II is in the prostate but can ALSO be in the inner rooth sheath!!!
Androgenetic alopecia will show what type of hairdo on biopsy
Vellus hairs, and MINIturized hairs
Which type of alopecia gives you vellus hairs and miniaturized hairs on biopsy?
Androgenetic alopecia
What is the difference between vellus hairs and miniturized hairs?
Vellus hairs have always been there
MINIturized hairs were previously large terminal hairs that have shrunk over time to become small hairs
Which are bigger - vellus hairs or miniturized hairs?
Neither they are the same size!
What is anisotrichosis and what condition is it found in?
Anisotrichosis is increased in variability of hair shaft size
*due to progressive miniturizationof terminal hairs in androgenetic alopecia
How does minoxidil treat alopecia?
Lengthens the anagen phase and increases blood flow
What part of the scalp is minoxidil most effective at treating?
The VERTEX scalp (>frontal scalp)
Finasteride is which type of 5 alpha reductase inhibitor? (Type I or Type II)
Type II!! (Found in the testicles and in the INNER root sheath)
Where does finasteride stop the reduction of testosterone to DHT?
In the inner rooth sheath - bc its a type II 5 alpha reductase inhibitor
What is the risk of women taking finasteride should they get pregnant?
Risk of abnormal male genitalia in fetuses
Which hairloss pill targets both type I AND type II 5-alpha reductase inhibitor?
Dutasteride!! (DUAL reductase) not yet approved in US tho technically
How many hairs is normal to lose a day?
100-150
How many hairs do you have to lose per day to be considered in telogen effluvium?
> 150 (100-150 hairs is normal to lose daily)
How many telogen hairs in a hair pull test of 40 hairs does it take to count as telogen effluvium?
4 out of 40
On biopsy -
- If you see >20% of hairs (but less than 50%) are telogen hairs, what condition do you think of?
- How abt >50% of hairs in telogen phase?
- 20-50% in telogen phase = telogen effluvium
2. >50% hairs in telogen phase = alopecia areata
What percentage of hairs are seen in telogen phase on biopsy in:
- Telogen effluvium
- Alopecia areata
- 20-50% (<15% in telogen is normal) seen in telogen effluvium
- > 50% seen in alopecia areata
What is a normal amount of hairs in telogen phase?
0-15% hairs should be in telogen phase normally. Anything greater is telogen effluvium or alopecia areata
Drug treatment of choice for trichotillomania
Clomipramine
Clomipramine is the TOC for what disorder?
Trichotillomania!
Prognosis is better for which age group with trichotillomania? Children or adults?
Better prognosis in children!!
What type of cells attack the hair follicle in alopecia areata?
Cytotoxic CD8 T cells!
What is a poor prognostic factor in alopecia areata?
Ophiasis pattern
Is ophiasis pattern alopecia areata a good or bad prognostic factor?
It is bad :(
What is the opposite of ophiasis pattern? In alopecia
Sisapho pattern
What is sisapho pattern in aa?
The opposite of ophiasis pattern
What do you see on dermoscopy in alopecia areata?
Exclamation point hairs, also perifollicular yellow dots
What other common skin condition is associated wtih alopecia areata and is a/w a poor prognostic factor?
Eczema (Atopic)
A person with atopic dermatitis is more or less prone to get alopecia areata? Is this a good or bad prognostic factor?
Atopy is actually a risk factor for AA, and it carries a poor prognostic factor :(
What is the condition called where you dont regrow any of your normal terminal hairs after shedding of their initial hairs after birth
Congenital atrichia with papules
Can also see follicular cysts and milia later in life
Congenital atrichia with papules
Congenital disorder where the patient does not regrow their terminal hairs after the shedding of their first hair after birth
*Can also see milia cysts and follicular cysts in a/w this disorder
Name this syndrome: scarring hairloss on the scalp, nonscarring hair loss of the axilla and pubic areas, KP like papules on the trunk
Graham-Little-Picarde syndrome
