Hair and Nails Dan Flashcards
1
Q
What are the causes of Pityriasis amiantacea?
what is treatment?
A
Psoriasis
seb derm
eczema
use strong keratolytics e.g. leave in coal tar and sal acid prep then topical steroids; diagnosis may become clear later
2
Q
What are Terry’s nails?
What are the associations?
A
White nails with a narrow distal pink/red/brown band May or may not see the lunulae Assoc; Liver failure Renal failure CCF Diabetes Hyperthyroidism Malnutrition POEMS
3
Q
T/F
FFA has been triggered by starting TNFα blockers
A
T
4
Q
How long is anagen phase for scalp hairs?
A
2-6 years
5
Q
How many scalp hairs are in anagen or telogen in the scalp?
A
90% in anagen
10% in telogen
small number in catagen - less than 1%
6
Q
How quickly does scalp hair grow?
A
1cm per month
7
Q
T/F
catagen phase is always about 2 weeks in all human hairs
A
T
No matter follicle type or site
8
Q
How long does telogen phase last on scalp?
A
3 months
9
Q
what is exogen?
A
end stage of telogen when new hair starts growing and telogen hair is shed from follice
10
Q
which keratins are found in hair?
A
mainly keratin 1 and 2 almost 50/50 ratio
11
Q
how many hairs are normally in a scalp follicular unit?
A
3-5 follicles connected to a single erector pili muscle
12
Q
how much scalp hair is lost before thinning become evident in most cases?
A
over 50%
13
Q
T/F
miniaturization is the process of terminal scalp hairs turning into vellus hairs mainly in pattern hair loss
A
T
14
Q
what is kenogen?
A
when a telogen follicle has lost its club fibre (telogen hair) but not yet transitioned to anagen
15
Q
T/F
type 1 5alpha reductase is found in the scalp, beard and chest hair follicles
A
F
type 2 5alpha reductase
converts testosterone to DHT which drives male AGA
16
Q
what are the major DDs for diffuse hairloss?
A
PHL/AGA acute TE chronic TE diffuse AA (rare) diffuse anagen effluvium - nearly always drug or disease
17
Q
T/F
AGA in prepubertal children who do not have precocious puberty/hyperandrogenism is rare and usually male pattern type
A
F
rare but usually female pattern type
18
Q
what is grading system for MPHL?
A
Hamilton or Norwood systems
19
Q
what is grading system for FPHL?
A
Sinclair or Ludwig systems
20
Q
what is trichodynia?
A
scalp paraesthesia
often occurs in PHL esp FPHL in 20-30% of women
21
Q
what is the Sinclair grading system of FPHL?
A
1 - normal
2 - widened central part line
3 - widened part + tanslucent border of central part line
4 - bald area along anterior of part line
5 - advanced hair loss
22
Q
what are key trichoscopic and histo features of AGA?
A
Trichoscopy;
variable hair shaft thickness due to miniturization
Peripilar sign - brown halos around hair ostia
yellow dots (yellow ostia)
Histo;
reduced ratio of terminal:vellus hairs from over 8:1 (nomal) to
less than 4:1
+ some increase in telogen follicle count and fibrous streamers
23
Q
what investigations should be done in PHL?
A
None routinely
If young women w/ not FHx or any other indication then do hormone screen
Consider TFTs, ferritin and zinc in all cases
sometimes B12, folate, VitD, ANA
If diagnosis unclear consider biopsy
24
Q
What is treatment ladder for PHL
A
reassure and do nothing - eg if normal temporal loss; does not indicate increased risk of further PHL in men or women
treat dandruff/scalp disease and any reversible causes of hairloss or nutritional deficiency
advise sun protection if scalp visible
assess psychosocial impact and manage as necessary
camouflage - hair styles, wig, toppik thickener, scalp dye
topical - minoxidil 5%
oral - minoxidil, finasteride, dutastride (men only)
women - cOCP, spironolactone, CPA
surgical - excision, flap, scalp expander, follicular unit transplants
25
what are the associations of alopecia areata?
```
Nail changes
Atopy inc eczema
Hypothyroid (hashimotos)
LS
IBD
Vitiligo
Autoimmune polyendocrinopathy syndrome 1
```
26
what nail changes are seen in alopecia areata?
```
brittle nails
onycholysis
Beau's lines
Onychomadesis
Koilonychia
Trachyonychia
Pitting - fine, organized (stippled), in grid pattern
```
27
what are poor prognostic factors in alopecia areata?
```
POLE V Yellow
Paediatric onset
Ophiasis
Long standing
Extensive
trichoscopy - vellus hairs, yellow dots
```
28
how long do nails take to grow?
fingernails 3mm/month
| toenails 1mm/month
29
T/F
| treating associated hypothyroidism will improve alopecia areata
F
| usually not but worth checking for and treating anyway
30
what is treatment ladder for AA?
Must assess psychosocial impact - if very concerned may treat more aggressively
General;
- Reassurance - 50% resolve in 1 year so if seen early can reassure only
camouflage - hairstyle, wig, toppik, scalp dye
artificial eye lashes, eyeliner pencil, wear glasses to disguise loss
Topical
- potent TCS
- tacrolimus - alone or as topical steroid sparer
- minoxidil (esp less extensive cases)
- dithranol 1% + 2% sal acid in YSP; apply 30mins initially inc to 2 hrs
- DPCP immunotherapy (3rd line)
systemic
- oral minoxidil
- steroid; esp if widespread inv. pred 25-40mg daily until regrown and reduce over 6-8 wks
can use IV methyl pred or IM triamcinolone
- Cyclosporin
- simvastatin-ezetimibe (40/10mg); small JAAD study
physicial;
- ILCS - 2nd lne after topicals for small areas of AA; 2.5-5mg/ml; must wait at least 4 weeks before repeating, usually 6
- PUVA has been reported
Surgery - usually not indicated
31
how is DPCP performed?
explain process to pt; 50% response rate; slow to see effects
- pts should not touch scalp for 6 hrs after application
- must avoid sunlight as degrades DPCP
- CIs - pregnancy, blood dyscrazia, malignancy
- AEs - severe erutpion, dyspigmentation, caregiver sensitization
sensitize on scalp or upper inner arm w/ 2% DPCP in acetone on filter paper in Finn chamber for 48 hrs
wait 1 week before starting immunotherapy
some advocate treating half the scalp initially and add in other half when response confirmed
start w/ 0.001% in acetone
Titrate up conc weekly as tolerated to reach point of; erythema +scale and itch lasting 2-3 days after application
0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1.0, 2.0
start to see response by 12 weeks
stop if no response at 24 wks
when hair fully regrown taper off by reducing frequency of application
32
how many hairs are normally lost from the scalp each day?
50-100
33
T/F
| 75% of cases of telogen effluvium are idiopathic
F
| 30%
34
what are the causes of telogen effluvium?
Physiological shed - women post partum, newborns
physical illness - shed some time after trigger
high fever - eg dengue, malaria
severe infection
major surgery or GA
chronic illness - HIV, SLE, SCLE, dermatomyositis
endo - thyroid disease, chronic hyperparathyroidism
nutritional deficiency eg iron, zinc, or massive weight loss, anorexia nervosa, bulimia, crash dieting
Drugs - ABCD ROME
chronic (idiopathic) TE
35
what are drug causes of telogen effluvium?
```
ABCD ROME
ACEi
Beta blockers
anti-coags
anti-depressants
Retinoids
OCP or stopping long term OCP
Minoxidil (initial shed), anti-Micorbials (isoniazid, indanivir)
Epileptics - valproate, phenytoin, carbamazepine
```
36
what are features of chronic TE?
usually women
age 30-60
TE lasting over 6 months
up to 30% get trichodynia
Can be caused by any of the causes of TE esp drugs and chronic disease as trigger is ongoing
Idiopathic if no cause found after investigation - diagnosis of exclusion
37
In what condition do you typically see short hairs regrowing at frontal hairline and parting?
resolving telogen effluvium
38
T/F
| hair pull test is negative in TE
False
usually highly positive
5-6 telogen hairs from each part of scalp as TE affects whole scalp
39
how many scalp hairs are in telogen in TE?
Over 20% is diagnostic
usually less than 50%
(normal is up to 10%)
40
what are trichoscopy features of TE?
Similar to PHL but affect whole scalp not just frontal and vertex
some miniaturization
peripilar sign
increased proportion of follicular units producing only 1-2 hairs
41
what is management of TE?
decide if acute or chronic (>6 months)
look for trigger in Hx +/- tests
assess for other cause of hair loss e.g. unmasked PHL
If isolated and acute w/ trigger reassure - resolves completely in 3-6 months
If chronic must investigate for triggers
can use topical or oral minoxidil
treat any scalp disease or other types of hairloss
camouflage usually not necessary as mainly an issue of shedding not thinning
42
T/F
| hairs lost in alopecia areata are catagen hairs
F
| dystrophic tapered anagen hairs
43
T/F
| anagen effluvium usually causes more widespread hair loss than telogen effluvium
T
thinning and often body affected not just scalp
cf - TE usually noticed by shedding and not much thinning
44
what are causes of anagen effluvium?
```
Infection
- tinea capitis, kerion
- boil or abscess
AI disease
- pemphigus vulgaris
Drugs; 3Cs and T-BAG;
- Chemo - MTX, 5FU, Doxorubicin, Bleomycin
- Colchicine
- Cyclosporin
- Thallium
- Bismuth
- Arsenic
- Gold
Radiation therapy
Loose anagen syndrome
```
45
what is trichoscopy of chemo-induced hairloss/ anagen effluvium?
Black dots
Exclamation mark hairs
Monilethrx-like hairs
46
how is anagen effluvium managed?
Treat cause
camouflage
minoxidil
For chemo - sometimes scalp cooling during chemo Rx can reduce haiross; hair grows back 3-6 months after end of chemo in most cases. Sometimes straight hair grows back curly
47
What is age and sex distribution for trichotillomania?
more common in kids;
peak in young kids, 5-12, rarely in preschool age
2nd peak in adolesence and young adults - more likely to persist
F:M 4:1 in older kids and adults, but in preschool boys more common than girls
48
what are the associations of trichotillomania in children, adolescents and adults?
Children - habits eg. nail biting, thumb sucking, nose picking, learning difficulty, anxiety, iron deficiency
Adolescents - bullying, abuse, body image issues, anxiety or depression
Adults - anxiety disorder, depression, OCD, eating disorder, substance abuse
49
what are DSM IV diagnostic criteria for trichotilomania?
1. recurrent pulling causing hairloss
2. tension when resisting and increase immediately before hair pulling
3. relief or please immediately after pulling hairs out
4. not part of another mental health disorder
5. interferes with normal social life or work etc
50
what is a hair growth window?
diagnostic technique used in trichotillomania
| shave small patch of hair in site and rw in one week to see normal uniform regrowth
51
T/F
| axillary hair is often involved in tricotillomania
F
Uncommon site
eyebrows and lashes common in children
body hair common in adults
52
what are clinical findings in trichotillomania?
ask about tension before pulling and gratification afterwards
ask about symptoms of associations dependent on age group - screen for anxiety, depression and suicidality in adolescents and adults and for bullying and sexual abuse in adolescents
may be vertex, temporal, frontal or occipital or non-scalp sites
often on side of dominant hand
can extend in centrifugal or linear pattern
may be secondary folliculitis
always ask about GI symptoms and hallitosis as some have trichophagia and can get bezoar (ball of hair in stomach)
Must assess impact on life
Trichoscopy -
broken hairs, hair powder, coiled hairs, split ends, flame hairs, V-sign, no major scalp/perifollicular changes
53
T/F
| biopsy plays minimal role in investigation of trichotillomania
F
Most useful investigation
Features -
normal size and number of follicles
empty follicles with no inflammation
pigment casts - boken off hairs leave small dark bodies
some increase in telogen and end-catagen hairs
may be follicular plugging or trichomalacia (deep distortion and curling of hair bulb)
54
How is trichotillomania managed?
Dont lay blame
consider need for barium swallow etc if bezoar suspected
Consider need for psych rw if suicidal, major anxiety, depression etc and for paeds admission/ child protection if abuse suspected
need good Hx for causes to address
esp in kids worth checking diet and testing for iron studies
some kids just need to address causes of stress or discourage behaviour
may need to refer to psych; TCAs can work
SSRI may help but best if combined with behavioural therapy
relaxation techniques
hypnosis
55
T/F
| pressure induced alopecia always resolves w/ time
F
not always
can be permanent or scarring loss
56
T/F
| temporal triangular alopecia affects young adult men
F
May be present at birth or onset in childhood, in 1st decade
temporal hair lost and replaced by vellus hair
follicle numbers the same
persists lifelong
57
what is lipoedematous alopecia?
mainly affects women w/ dark skin
thick boggy area of hairloss at vertex
oedema and thickening of fat layer on path but no inflammation
follicles replaced by fibrous tracts
can be boggy scalp and path changes without hair loss
58
T/F
| thyroid disease causes hair loss known as 'glades in the wood'
F
| this is secondary syphylis - describes patchy hairloss
59
which systemic disease cause hairloss?
```
all typically telogen effluvium type except pempigus vulgaris which causes anagen effluvium;
SLE - also causes 'lupus hair'
SCLE
Dermatomyositis
thyroid disease esp hypo
secondary syphylis
iron deficiency
zinc deficiency
malnutrition or crash dieting
```
60
what is lupus hair?
dry coarse hair w/ non-scarring alopecia in SLE
61
what scalp skin diseases can cause hairloss?
Tinea capitis esp kerion - can be scarring
psoriasis - can be scarring
thick seb derm
62
what are trichoscopy findings to tinea capitis?
comma hairs
corkscrew hairs - more tightly coiled comma hairs
black dots - esp endothrix
rare - morse code hairs
can combine w/ Woods lamp for UV-enhanced trichosocpy
63
what are biphasic types of alopecia?
Non-scarring types that can become scarring if continue for long time
E.g. AGA, AA, traction alopecia, pityriasis amiantacea
also alopecia due to psoriasis or tinea capitis
64
what are secondary causes of scarring alopecia?
Not primarily a scarring alopecia disease but causes follicle detruction
causes are trauma, sclerosing diseases, infection and malignancy;
E.g. skin cancer, deep burn, XRT, sarcoidoisis, radiation dermatitis, scleroderma, linear morphoea (eg en coupe de sabre), cicatricial pemphigoid (scalp affected in 10%), NLD, infections e.g. TB, tinea capitis
65
which scarring alopecias are lymphocytic and which are neutrophilic?
```
Lymphocytic:
DLE
LPP
pseudopelade of Brocq
CCCA (neuts too if infected pustular type)
alopecia mucinosa
```
Neutrophilic:
FDC
Dissecting cellulitis
```
Mixed:
acne keloidalis nuchae
erosive pustular dermatosis
inflammatory tinea capitis
acne necrotica
```
66
what genetic or congenital disorders can cause scarring alopecias?
```
aplasia cutis
epidermal naevus
hair follicle hamartoma
incontinentia pigmenti
Goltz syndrome
porokeratosis of Mibeli
Icthyosis
EB
Conradi-Hunerman
bullous porphyrias
```
67
what are major categories of causes of scarring alopecia?
Primary scarring alopecias
Biphasic alopecias
secondary causes of scarring alopecias; Trauma, sclerosing, infections, neoplasms
Genetic and congenital causes of scarring alopecia
68
what triggers erosive pustular dermatosis?
Surgery, cryotherapy, XRT, skin grafts on scalp most often in pts w/ existing advanced AGA
69
what are histo features of erosive pustular dermatosis
epidermal erosion
chronic lymphocytic infiltrate; often plasma cells
destruction of follicles often w/ surrounding fb granulomatous reaction
70
T/F
| erosive pustular dermatosis is treated with potent steroids
```
T
swab to exclude infection
+/- biopsy to exclude IEC
sun protection
potent TCS w/ slow taper over months then mod TCS for control
```
71
T/F
| central centrifugal cicatricial alopecia is triggered by hair relaxers or hot combs
T
can be
but continues even after pt has stopped using these
72
what are clinical and histo features of CCCA?
chronic progressive scarring alopecia esp in black women
starts at crown or vertex and expands centrifugally and symmetrically - active inflammation at edge
can be some polytrichia tufts in central scarred area
can be infection and pustules at active edge
mild pruritus or tenderness
Histo
lymphocytic infiltrate
atrophy of follicle epithelium
concentric lamellar fibrosis of follicles (onion peel)
can be hair fragments and fb granulomatous reaction
73
How is CCCA treated?
stop using hot combs, relaxers etc
Potent TCS + Doxy 1st line
if pustules present start w/ 10 week course of rifampicin + clindamycin then Doxy and TCS
Can need long term Rx
74
what are the types of LPP?
Classic
FFA
Graham-little syndrome
75
T/F
| LPP is the most common scarring alopecia
T
76
How many LPP pts have LP elsewhere?
50%
| can be skin, nails, genital/mucosal
77
T/F
| FFA has been triggered by starting ustekinumab
F
| has been triggered by starting TNFalpha blockers
78
what are the associations of LPP?
autoimmune disease esp hypothyroidism
also reported; lupus, sjogrens, hep C
do FBC, ELFT, TFTs and ANA
79
what is the course of progression of LPP?
usually affects several foci, can be linear
course;
violaceous perifollicular erythema
follicular keratotic spines
scarring loss of ostia and perifollicular scale
lonely hairs - few single hairs isolated in scarred areas
80
T/F
| LPP usually shows lichenoid change of follicles and overlying DEJ
F
| interfollicular dermis spared and overlying DEJ very rarely involved
81
what are the features of Graham-Little syndrome?
KP
LP - skin or mucosa
LPP scarring alopecia
Non scarring hair loss of axillary and pubic hair
82
what are the trichoscopy features of LP?
Intense perifollicular scale is most characteristic
can be tubular scale structures migrating along hair shaft
fibrotic white dots represent scarred ostia
milky red fibrosis
concentric linear bood vessels
lonely hairs
83
what is histo of LPP
lichenoid infiltrate of follicle epithelium in region of isthmus and infundibulum - does NOT extend down to bulb
usually no interfollicular and little or no DEJ inflamation
perifollicular fibrosis
can be cleft between folllicle and stroma
84
what is treatment ladder for LPP?
```
topical steroid - mainly help symptoms
ILCS
HCQ - main Rx after steroids
Oral pred 30-40mg next best Rx
Acitretin or isotretinoin
Doxycycline
MMF or CsA
Pioglitazine
Tacromlimus, Thalidomide, Pioglitazone
rarely - MTX, TNFalpha blockers, Excimer laser
```
```
Rx of FFA;
TCS
ILCS
Short course oral pred
HCQ
Doxy
Pioglitaone
New - oral minoxidil + finasteride or dutasteride
```
85
T/F
| sometimes DLE can mimic AA
T
| less inflammatory types can mimic AA or morphoea
86
what are trichoscopy features of DLE?
Large yellow-brown dots are characteristic - dilated plugged ostia
can be follicular red dots - good prognostic sign of regrowth
thick arborizing vessels at peripheral edge of lesions
end stage lesions show white fibrosis
87
How does histo of DLE differ from LPP?
DLE is mainly vacuolar type lichenoid w/ less florid lymphocytic infiltrate
not confined to isthmus/infundibular region
often chronic inflammation interfollicular dermis; may be plasma cells
DEJ may be involved
IMF shows granular IgG and C3 at junction of follicle epithelium and dermis and/or DEJ
88
T/F
| pts wit DLE of scalp are more likely to develop SLE than if they have DLE elsewhere
F
| very rare to get SLE if scalp DLE only
89
what is treatment ladder for DLE?
very similar to LPP
dont forget sun protection
steroids - topical or intralesional
oral steroids sometimes used to induce remission
HCQ - mainstay of Rx; usually remission in 3mnths
If resistant; acitretin, dapsone, thalidomide
(last line; CsA, MTX, MMF)
90
T/F
| acne keloidalis 5x more common in black people
F
| 10x more common
91
whats aetiology of acne keloidalis nuchae?
complex, poorly understood
primary scarring alopecia not only due to ingrowing hairs
may be a role for ingrowing hairs, staph and folliculitis w/ fb reaction
similar to dissecting cellulits
may co-exist w/ CCCA - can meet in middle
92
what are clinical features of acne keloidalis nuchae?
smooth follicular papules on neck area of hair resolve leaving small areas of alopecia
coalesce into large firm keloidal plaques
can be abscesses and sinus tracts
93
what is histo of acne keloidalis nuchae?
perifollicular chronic inflammation - lymphs, plasma cells, can be neuts, can be fb granulomatous rcn
loss of sebaceous glands and follicles w/ lamellar fibroplasia
can be extruded hair fragments
may see abscesses and sinus tracts
94
what is Mx of acne keloidalis nuchae?
```
dont cut hair too short
avoid rubbing collars
swab for secondary infection
Doxy is mainstay
TCS can help settle inflamation
ILCS esp if firm nodules
sometimes oral pred to settle
for large firm keloids - ILCS, Cryo, PDL, excision
iostretinoin
rarely - XRT or surgery followed by XRT
```
95
who gets dissecting cellulitis?
| what is the cause?
young black men most often
can be part of follicular occlusion tetrad
cause known - thought to relate to obstruction of hair follicles and chronic infection
genetic tendency
96
what are clinical features, trichoscopy and histology of dissecting cellulitis?
starts on occiput/vertex
firm inflammatory nodules, superficial and deep abscesses
connect into thick, boggy fluctuant mass w/ oval or linear ridges
hair lost from summits of nodules/ridges but retained in valleys
develop scarring
can be a spondyloarthropathy - joint activity follows scalp
trichoscopy shows 3D yellow dots superimposed over dystrophic hair shafts + yellow structureless areas - end stage shows white fribrosis
Histo;
Dense perifolliculitis of lymphocytes, histiocytes, neuts
abscesses and sinus tracts
destruction of follicles
hair fragments with fb granulomatous rcn w/ plasma cells
end stage is fibrosis and loss of appendages
97
what is management ladder for dissecting cellulitis?
swabs for bacteria and fungus and Rx as appropriate
Rx similar to acne fulminans or pyoderma faciale;
high dose pred 1mg/kg + EES then introduce isotretinoin and increase to 1mg/kg; then stop EES after 4 weeks iso and slowly wean pred and replace w/ TCS - can use ILCS if necessary. Continue iso for at least 6 mths and usually until 4 mths after skin settled then wean off
Other options;
Doxy
zinc sulphate +/- oral and topical fucidic acid
TNFalpha inhibitor
CO2 laser
surgery
- incision and drainage
- excision and grafting
98
what is folliculitis de calvans?
Very inflammatory scarring alopecia
occurs in adults esp women in 30s
May be some kind of staph hypersensitivity
neutrophilic inflam infiltrate
single area of enlarging scarring alopecia w/ inflamation and folliculr pustules + crusting at edge; Polytrichia is often seen - tufts of 5-20 shafts or more
rare patterns;
- multifocal
- spread around margin of scalp
- spread around margin of pre-existing baldness from AGA
99
what are histo features of FDC?
follicular abscesses with dense perifollicular infiltrate of neuts + some eos and plasma cells (does not have the thickness and sinus tracts of dissecting cellulitis)
also fb granulomas, follicle destruction and fibrosis
must do PAS to exclude inflammatory tinea capitis
100
what is management of FDC?
swabs +/- pluck hairs to r/o bacterial and fungal infection
clindatech and TCS usually first line - add orals if not responding
long course of antibiotics e.g. Doxy 1st line fluclox sometimes
Rifampicin + clindamycin or sometimes rifampicin + fucidic acid/cipro/doxy
isotretinoin - can induce LT remission in some pts
Metvix PDT reported
topical keratolytic can help tufting
101
what is tufted folliculitis?
The presence of a cicatricial alopecia with marked polytrichia
some consider a variant of FDC w/ prominent tufting
some consider as just the presence of prominent tufting that can be part of any scarring alopecia and can be seen in inflammatory tinea or pemphigus vulgaris
Is not a complete diagnosis on its own
102
what is pseudopelade of Brocq?
Poorly defined entity - some say is a specific diagnosis but other don't believe that and see it as a pattern of scarring alopecia caused by another aetiology
pelade means alopecia areata and pseudopelade means scarring alopecia
Pseudopelade of Brocq is scarring alopecia in a patchy pattern usually called 'footprints in the snow' - later it can colaesce into larger areas
this pattern affects mainly women in 40s
areas are smooth, soft and may be slightly depressed on palpation - there is no discolouration or scale
the hairs on the edge of the patches may be easily pulle dout if disease is active
histo classically shows follicles replaced by fibrous streamers but no inflammation
often it is slowly progressive
essentially a diagnosis of exclusion
No effective treatment
if burnt out can consider surgery on scarred areas
otherwise camouflage is mainstay
103
what are the inflammatory types of tinea capitis?
small spored ectothrix e.g. M. canis, M. equinum, M. audouiii
agminate folliculitis e.g. M. canis, T. mentag mentag (zophilics)
Kerion - esp T. mentag mentag, T verrucosum
favus - T. schonleineii
104
what is agminate folliculitis?
type of inflammatory tinea w/ well-defined dull red paques studded w/ follicular papules
caused by zoophilic dermatophytes
105
T/F
| biopsy is rarely necessary for scarring alpecias
F
| biopsy is essential - cannot distinguish without
106
Which stuctural hair abnormalities are associated with increased fragility?
```
Bubble hair
Monilethrix
Pili torti
Trichorrhexis nodosa
Trichorrhexis invaginata
Trichothiodystrophy
```
107
which structural hair abnormality cannot be diagnosed by trichoscopy alone?
Trichothiodystrophy
| Need polarised light microscopy
108
what is Bubble hair?
localised area of bubbles in hair shaft - hairs are brittle
| hairs are short, uneven and kinky
109
What is monilethrix?
means necklace hairs - beaded appearance like a pearl necklace
AD w/ variable expression
mutation in keratins 81 or 86
normal hair at birth then after shed is replaced by short, brittle, kinky fair hair
often have KP; can have koilonychia or other nail changes
trichoscopy/mount shows nodes of fusiform thicker areas in between internode constrictions
110
What is Pili torti?
| what are main associations?
Twisted hairs
shaft is flattened and twists in groups of 3-10
can be genetic syndrome alone or part of larger syndrome e.g;
Bjornstad's syndrome - AR w/ sensorineural deafness
Menke's syndrome - X-linked copper transport Dx + get trichorrexis nodosa + in 40% of female Menke's carriers
Can be acquired e.g. Anorexia nervosa, at edge of DLE or LPP lesions or in 'retinoid hair' due to aciretin or isotretinoin
111
What is trichorrhexis nodosa?
'No don't paint me!'
Brush breaks in hair shafts like ends of paint brushes pushed together
patches of short kinky broken hairs - not usually generalized
Can be part of Nethertons
Also congenital and acquired forms - congenital form accompanied by metabolic defects and mental retardation; can be seen in trichothiodystropy with icthyosis
Acquired - due to straightening trauma etc, can occur in beard
112
What is trichorrhexis invaginata?
Bamboo hair defect characteristic of Netherton's
When hair breaks at defect golf-tee shaped socket end remains
- scalp, eyebrows and lashes affected affected in Nethertons - hair doesnt grow long in infants; scalp hair improves in adults but remains affected elsewhere; most easy to identify in eyebrow hairs
113
What hair defects are seen in trichothiodystrophy?
Literally means sulphur-deficient hair
Pts usually have intellectual impairment and may have photosensitivity
Hair is patchy and brittle
most characteristic feature is tiger tail hair - alternate light and dark bands only seen on polarised light microscopy
Can also get - trichoschisis (clean transverse fractures), distal trichorrhexis nodosa, pili torti
114
What is loose anagen syndrome?
Familial disease w/ faulty cornification of inner root sheath - hair is poorly anchored into follicle
children esp girls have short, blonde hair
+ve hair pull test - loose anagen hairs are characteristic; roughened proximal cuticle - looks like ruffle sock on a hockey stick
115
What is pili annulati?
shiny hair due to bright and dark regions in hairs under reflected light - lighter areas are due to abnormal air-filled cavities in the hair
AD or sporadic trait
On microscopy the light areas are dark regions
116
What is Pili trianguli et canaliculi?
Uncombable hair or Spun glass hair
hair is triangular in cross section - has longitudinal grooves visible on EM
looks like spun glass when it reflects light
is stiff and hard to comb and usually silvery colour, presents in childhood
improves in adulthood but defect still visible on microscopy
117
what is woolly hair?
tightly curled hair sometimes w/ various microscopic features e.g. elliptical cross section, axial twisting, trichorrhexis nodosa
can be all over scalp as AD or AR trait
can be localised patch = woolly hair naevus
can be part of 3 AR syndromes w/ cardiomyopathy;
- Naxos disease
- Carvajal syndrome
- EBS-desmoplakin; skin fragility woolly hair syndrome
Also seen in Noonan's or cardio-facio-cutaneous syndrome
Can be retinal defects in pts w/ Woolly hair naevus - refer to ophthal and to gen paeds in kids as risk of precocious puberty
118
what is trichoschisis?
clean transverse fracture in hair shaft
| can occur in trichothiodystrophy
119
what is trichoclasis?
Greenstick fracture of hair
| can occur in trauma
120
what is trichoptilosis?
split ends
| occur due to trauma
121
What are circle hairs?
circle or spiral hairs trapped under stratum corneum layer
122
What is trichomalacia?
has different clinical and histo definition;
clinical - softened hair residue and keratin in an open follicular orifice in the scalp
histo - deep distortion and curling of hair bulb
123
What is a Pohl-pinkus constriction?
a zone of constriction in a hair shaft due to a phase of poor growth
similar to beaus's line - occurs due to illness etc
124
T/F
| new anagen hairs have blunt ends
F
have pointed ends
blunt ends seen in broken hairs
125
What is trichonodosis?
knots in the hair
| happen in very curly hair e.g. afro-caribbeans
126
What is bayonet hair?
slight kink in the hair within 1-2mm of the tip
| normal variant
127
What are hair casts?
AKA pseudoknits
keratin cylinders at base of hair shaft - arise from upper part of inner root sheath
seen in scaly scalp conditons or styles with tension on hair
128
```
T/F
the following cause nails to grow faster;
Young age
male sex
Summer time
nails on right hand
pregnancy
hyperhtyroidism
azathioprene
```
```
F
all true except AZA
AZA and MTX and L-Dopa slow nail growth
Itraconazole speeds up nail growth
Acitretin can speed up nail growth in Pso pts but otherwise slows it down
```
129
What are Beau's lines?
| what are causes?
transverse depressions in nail due to period of reduced growth
causes of Beau's lines and onychomadesis are the same
e.g. severe illness, erythroderma, dialysis, immunodeficiency
derm Dx affecting nails eg. BP, PV, linear IgA, paronychia, SJS/TEN, nail pso, pustular pso, LP, Raynauds
drugs esp chemo also retinoids, penicillin, azithromycin, lithium, lead antiepileptics
130
What is onychomadesis?
| what are causes?
```
detachment of nail plate from prox nail fold - more severe form of Beau's line - nail still attached to bed but falls off after some time
due to complete arrest of nail matrix activity for a time
all same causes as Beau's lines
also some specific associations;
alopecia areata
Kawasaki disease
MF
infections eg. hand, foot + mouth, varicella, candida, dermatophyte, fusarium, meningitis
Other types;
familial
idiopathic sporadic onychomadesis
seasonal onychomadesis
```
131
What is retronychia?
| what are causes?
proximal ingrowing of nail into ventral surface of nailfold
similar to beau's and onychomadesis but directon of nail growth altered by insult
caused by trauma, OA or thrombophlebitis
can diagnose on USS in pt w/ chronic proximal paronychia or abnormal onychomadesis
avulse nail - usually grows back normally
132
what are causes of nail pitting?
```
focal deep large pits;
Psoriasis, Reactive arthritis, trauma
diffuse shallow pits;
alopecia areata (geometric), SLE, Eczema
can be seen w/ other changes in tinea unguim
```
133
what is onychorrhexis?
| what are causes?
thin brittle nails w/ superficial grooves + can be distal splitting
e.g. Old age, LP, RA, Raynaud's, Darier's, tumour compressing matrix
134
What causes longitudinal grooves in nails?
habit tic - pushing back cuticles or onychotillomania
subungual tumour etc e.g. glomus, myxoid cyst, verruca, SCC, melanoma, pterygium
Median canaliform dystrophy of Heller = wide deep central split with inverted fir tree like appearance
- spares cuticle
- several causes; familial, trauma, retinoids
135
What is trachyonychia?
| what are causes?
rough surface to nails like sandpaper - due to many tiny pits
causes;
Pso, alopecia areata, eczema, LP retinoids, trauma
20 nail dsytrophy - idiopathic widespread variant
136
what is 20 nail dsytrophy?
d
137
what is koilonychia?
| what are causes?
spoon-shaped nails with concave curvature in transverse and longitudinal directions
is normal in infancy esp thumb and big toe - self resolves
familial AD trait is most common cause of koilonychia starting at young age and persisting into adulthood (nail disorder, non-syndromic congenital 2)
other causes; iron deficiency, haemochromatosis, trauma
can be seen in pts w/ trichothiodystrophy or monilethrix
138
what is a pterygium?
| what are types and causes?
Dorsal pterygium is most common = scarring between nail fold and matrix resulting in no nail growth from part of the matrix - instead skin grows out from prox nailfold onto nail bed in a triangular appearance
e.g. LP also sarcoidosis, leprosy
Ventral pterygium is when the nail bed epithelium extend forward disrupting the hyponychium
e.g. scleroderma also Raynauds, LE, trauma, familial, infection
139
what is onycholysis?
| what are causes?
detachment of distal nail plate from bed
e.g.
trauma/toxic - wet work, irritants, traumatic nail picking
Pso, LP, dermaitis, bullous dermatoses, onychomycosis
hyperthryroidism, PCT
photo-onycholysis - psoralens, doxycycline, NSAIDs, amioderone etc
tumour of nail bed
AR hereditary distal onycholysis
140
what is onychochuxis?
| what are causes?
```
= subungual hyperkeratosis
e.g.
Pso
PRP
onychomycosis
eczema
```
141
what are causes of splinter haemorrhages?
trauma - distal and longitudinal
Pso
onychomycosis
systemic (usually proximal) e.g. infective endocarditis, vasculitis, SLE, antiphospholipid syndrome
142
What is apparent leukonychia?
| what are causes?
Apparent leukonychia
- Generalised e.g. anaemia, oedema, vascular impairment of nail bed
- nail bed anomoly causing white appearance that disappears w/ pressure
- Terry's nails; White proximally w/ distal 20% normal/red/brown e.g. cirrhosis, CCF, T2DM
- Half and half nails; white proximally w/ distal 50% brown e.g. CRF, chemotherapy
- Muehercke's nails (striate leukonychia); Transverse white lines parallel to lunula e.g. SLE, low albumin, nephrotic syndrome
143
How is Leukonychia classified?
True leukonychia
- disturbed keratinizaton causes parakeratosis in nail plate resulting in loss of translucency and white appearance that doesnt disappear with pressure
- Punctate
- Longitudinal
- Transverse = Mee's lines
- Complete = nail disorder, non-syndromic congenital 3
Apparent leukonychia
- nail bed anomoly causing white appearance that disappears w/ pressure
- Generalised
- Terry's nails
- Half and half nails
- Muehercke's nails (striate leukonychia)
Pseudo-leukonychia
- white discolouration other than those above
144
what is pseudo-leukonychia?
| what causes it?
Pseudo-leukonychia
- white discolouration not cased by nail bed parakeratosis or nail bed anomoly
e. g. white superficial onychomycosis
145
What is true leukonychia?
| what are causes?
True leukonychia
- disturbed keratinizaton causes parakeratosis in nail plate resulting in loss of translucency and white appearance that doesnt disappear with pressure
- Punctate e.g. Pso, alopecia areata
- Longitudinal e.g. Dariers, Hailey-Hailey
- Transverse = Mee's lines; truly transverse across nail and do not curve e.g. trauma, chemo, renal failure, heavy metal poisoning
- Complete = nail disorder, non-syndromic congenital 3; AD/AR - PLCD1 gene muations
146
what causes erythronychia?
anything that causes thinning of the nail plate makes the nail look more red
Can be any type of skin tumour or tumour arising from adjacent bone or cartilage disrupting the matrix
also local skin Dx e.g. Dariers, AKV of Hopf, LP, Pso, DLE, Langerhans cell histiocytosis
147
what are causes of longitudinal melanonychia?
activation of nail matrix melanocytes - usually several nails
melanoctyic lesions - naevus, lentigo, melanoma
triggers for nail matrix melanocyte activation -
Racial melanonychia (often increases w/ age)
Pregnancy
Addison's
PIH after local dermatosis e.g. LP, Pso, onychomycosis
Inherited pigmentary disorders e.g. Laugier-Hunziker, Peutz-Jehger
Trauma - esp lateral 2 toenails
Drugs - tetracyclines, hydroxyurea, chemo (5FU, Doxorubicin), cyclophosphamide, psoralens, zidovudine
148
What features are concerning when assessing longitudinal melanonychia?
Single affected nail
Age - adults over 40
brown-black w. different colours/ variegated borders
3mm or wider in diameter
Hutchinson's sign - pigment extends to proximal and/or lateral nail fold
rapidly changing esp if band widening
Hx - any high risk melanoma features in history e.g. one or more melanomas in past
149
What are the causes of longitudinal melanonychia in children?
when should you biopsy?
```
Most due to subungual lentigo
some are subungual naevus or atypical naevus
Dermoscopy NOT useful
can usually manage conservatively
Think to biopsy if (same as for adults really);
multicoloured
Hutchinson's sign
pigment band 3mm or more
```
150
What is green nail syndrome?
what causes the green colour?
how is it treated?
Due to infection with pseudomonas aeruginosa
usually starts as onycholysis or chronic paronychia which allow pseudomonas to get in
usually only 1 or 2 nails
nail looks green due to accumulation of pyocyanin under the nail plate
Rx
1:4 white vinegar soaks BD
gentamycin
identify and treat pre-existing nail disease
151
what are the genetic disease causing complete or partial absence of the nails?
Complete absence of nails
- Nail disorder non-syndromic congenital type 4
- AR
- mutation in RPO4 (R-spondin 4) - Wnt signalling pathway
Partial absence of nails
- Nail disorder non-syndromic congenital type 6
152
What is the ABCDEF list for suspected nail melanoma?
Age - peak in age 40-60s
Brown-Black, Breadth 3mm or more, Borders variegated
Changing colour or breadth / failed to change after Rx
Digits most often affected - thumb and big toe
Extension of pigment to nailfold
Family or personal Hx of MM or dysplastic naevi
153
what is onychoschizia?
what are causes?
what is management?
Distal free edge of nail plate splits horizontally into multiple plate-like layers
causes; chronic trauma, wet work, picking etc
Sometimes due to poor nutrition, iron deficiency etc - if only fingernails affected less likely systemic cause
Mx
reduce trauma and wet work
wear cloths
moisturize
keep nails short
avoid acrylics and other nail cosmetics
avoid nail affecting drugs such as retinoids
check iron, zinc and albumin levels - discuss diet
biotin 5-10mg/day may help - trial for 2-3 months
154
what causes chronic paronychia?
| How is it treated?
Inflammation of prox and/or lateral nail fold
- red, swollen, cuticle usually lost
chronic course w/ periodic exacerbation
often sec infection w/ candida or pseudomonas
Causes;
Irritation eg wet work and trauma
contact dermatitis ICD or ACD
food hypersensitivity (allergy) eg limes, garlic ACD
Candida hypersensitivity
True primary chronic candidal paronychia - rare; can be in HIV or chronic mucocutaeous candidiasis eg immunodeficient
neoplastic - due to adjacent SCC, IEC etc
Drug-induced - chemo, retinoids, antiretrovirals
Mx
hand care; avoid trauma and wet work, wear gloves for work w/ hands
no nail cometics while settling then avoid excessive manicuring etc
swabs fro baceria, fungus, yeast
consider need or biopsy or imaging
topical TCS or tacro BD
topical nizoral cream BD
topical antiseptic soak eg. vinegar, Condys
severe cases may need ILCS (2.5mg/ml monthly) or short course oral prednisolone
Usually oral antifungals not needed but may do if candida confirmed
155
What is acute paronychia?
| how is it managed?
In acute paronychia there is rapid onset erythema, swelling, heat and pain and often a pointing asbcess
Causes; picking or biting nails, thumb sucking, manicures or other traumas, ingrown nails, drugs - retinoids, EGFR inhibitors, BRAF inhibitors
Mx
can be bacterial or viral - must swab (rarely fungal)
Often need incision and drainage
topical antibiotics or antiseptics
sometimes need oral antibiotics or antivirals
156
What is onychocryptosis?
| what is management?
Ingrown nails
usually toe nails esp big toe
usually lateral nailfold
can occur in pts w/ congenital malalignment of the great toenails
can be triggered by improper nail cutting, or pointed shoes or other trauma to the nail
retinoids can trigger
higher risk if hyperhydrosis
Mx
removal of edge of nail
uplifting lateral nail plate w/ cotton or dental floss after warm water soaks several times each day
destruction of lateral nail matrix e.g. surgery, laser, phenol
can be hypertrophy of lateral nail fold which may need surgery
157
what is onychogryphosis?
| what are causes and management?
Thick yellow nail like a rams horn
ageing, psoriasis, trauma
nail avulsion is treatment of choice
158
What causes pincer nails?
| what is management?
hereditary or acquired
toenails usually affected, often painful
excess transverse curvature causes compression of distal nail bed
causes;
Inherited - thumbs and big toes, onset in adulthood; other nails involved later but usually less so
psoriasis
Individual pincer nail - MRI to investigate for tumour of matrix
159
T/F
| periungual fibromas are rare in the general population
F
common
But if multiple consider TSC (Koenen's tumours)
160
What is management of digital myxoid cyst?
Cryotherapy 1st line
- empty of gel then apply pre-frozen probe for 4-5 secs
if unsuccessful refer to hand surgeon for definitive management
some suggest - repeated drainage, sclerotherapy, steroid injection
but often recur
161
What is subungual exostosis?
bony outgrowth of terminal phalanx that forms a firm lump and can lift the nail plate
162
How do glomus tumours present?
| how is it managed?
painful blue-red macule beneath nail
Can present w/ longitudinal groove, longitudinal erythronychia, pincer nail etc
Get MRI to assess extent and refer to hand surgeon
163
What is Onychomatricoma?
fibroma of the proximal nail fold, closely associated with the matrix
causes focal or complete thickening of nail plate mimicking subungual hyperkeratosis with multiple holes in thickened free margin representing tunnels of tumour
164
T/F
| periungual SCC is associated with HPV
T
esp HPV16
also 18 and 34
165
what is treatment for periungual SCC, KA or IEC?
```
SCC-
X-ray to rule out bony involvement
Moh’s micrographic surgery
Local excision
Digit amputation
XRT
- rarely need ampuation for digital IEC but complete excision recommended - non-surgical methids not advisable (PDT, efudix etc)
- KAs can invade phalanges and dont regress as they do elsewhere; treat aggressively like SCC
```
166
T/F
| Psoriasis can cause almost every possible nail change
T
167
What are the main nail changes of psoriasis?
Irregular large deep pits
Salmon patches (‘oil drop’ sign) – due to focal parakeratosis of nail bed and lifting of nail
Onycholysis w
splinter hemorrhages, subungual hyperkeratosis, nail plate thickening and crumbling, paronychia
168
What is treatment ladder for psoriatic nail disease?
JAMA Derm rw 2015:
General;
Avoid trauma/manicures, keep nails short, emollient, gloves for wet work
Evaluate for PsA – refer to rheum if appropriate
Consider extent of Pso – do they qualify for systemic/biologic based on skin severity
Exclude onychomycosis
Rx;
Topicals first line;
- Potent TCS (clobetasol in studies)
- Daivobet gel
ILCS – 1st line non systemic if failed topicals
MTX – 1st line systemic if cant get biologic
Acitretin – 2nd line non biologic systemic
Biologics – adalimumab>etanercept (then ILCS)>ustekinumab (But nails alone don’t qualify on PBS)
If skin and Nails bad;
1st line – adalimumab>etanercept>ustekinumab
2nd line – MTX>Acitretin> infliximab>apremilast
If skin, nails and joint disease;
Adalimumab>etanercept>ustekinumab>infliximab> MTX>apremilast>golimumab
169
T/F
| Acrodermatitis continua of Hallopeau arises in pts with plaque psoriasis
F
| considered a variant of pustular Pso but doesnt usually arise in pts w/ Pso vulgaris
170
what are features of Acrodermatitis continua of Hallopeau?
Relapsing episodes of acute painful inflammation with pustules around and under nail plate
Others: onycholysis, onychomadesis, and scaling of the nail bed and periungual skin
171
What is management of Acrodermatitis continua of Hallopeau?
```
May need biopsy to confirm diagnosis
Potent TCS (clobetasol, dip OV)
Daivonex/ Daivobet
Tacrolimus
Efudix reported
Acitretin in severe cases
MTX
TNFs – but can trigger pustular pso
PUVA - topical
```
172
T/F
| 10% of cases of LP involve the nails
T
| esp seen in pts over 40
173
T/F
| LP of the nails is commonly associated with LP elsewhere
F
| often isolated nail disease
174
What are features of lichen planus of nails?
Nail thinning esp lateral edges
Ridging
Longitudinal Fissuring or distal splitting
Dorsal pterygium
Others;
onycholysis, subungual hyperkeratosis, yellow discoloration, loss of nail
175
How is nail LP managed?
Systemic therapies may be required to avoid pterygium formation – pred, retinoids
Pre-Rx biopsy of matrix is ideal to confirm diagnosis
Resistant to TCS
Topical tacro may work
If only 1 or few nails ILCS into prox nailfold – 2.5-5mg/ml
Systemic treatment usually required – pred 1st line; 25mg OD for 4 wks then taper over 2-4 weeks – can induce long term remission but recurrence is common
Alitretinoin reported (not in Aus)
Etanercept reported
176
What is cause of 20 nail dystrophy?
unknown
| some cases may be lichen planus - seen in children however LP of nails is otherwise rare in kids
177
What is 20 nail dystrophy?
| How is it managed?
Widespread trachyonychia involving majority of nails
Mostly occurs in childhood
Cause unknown but some cases AD (gene unknown)
May have LP, Pso, eczema, alopecia areata
can be thinning, thickening, pitting, ridging, koilonychias, opalescence or loss of lustre or some nails may be spared
No good Rx;
check for associations
topical, IL and systemic steroids used
Can try topical PUVA
178
What nail changes may be seen in pts w/ eczema?
Irregular pitting and beau’s lines
Subungual hyperkeratosis
Chronic paronychia
179
T/F
| Dermatomyositis pts get Dilated nailfold capillaries and Drop-out of capillaries as well as ragged cuticles
T
180
What is Lovibonds profile sign?
Feature of digitial clubbing
| Lovibond’s angle between proximal nail fold and nail plate (normally 180˚
181
What is Curths’ modified profile sign?
Feature of digitial clubbing
Curth’s angle of distal phalanx relative to the more proximal phalanx across the DIPJ is normally about 180˚ and is reduced to
182
What is Schamroth’s sign?
Feature of digitial clubbing
| Closure of Schamroth’s window
183
What is Shell nail syndrome?
rare variant of clubbing associated w/ bronchiectasis; nail looks similar but distal nail bed is atrophic and distal nail curves over an empty space rather than soft tissue
184
T/F
| Clubbing occurs due to enlargement of the soft tissue pulp of distal digit
T
Increased longitudinal and transverse nail curvature
cause unknown but may be due to altered vagal tone or microvascular infarcts
185
What are the causes of digital clubbing?
Lung disease:
Lung cancer, mainly non-small-cell (54% of all NSCLC)
Interstitial lung disease most commonly fibrosing alveolitis
Tuberculosis
Suppurative lung disease: lung abscess, empyema, bronchiectasis, cystic fibrosis
Mesothelioma of the pleura
Arteriovenous fistula or malformation
Heart disease:
Any disease featuring chronic hypoxia
Congenital cyanotic heart disease (most common cardiac cause)
Subacute bacterial endocarditis
Atrial myxoma (benign tumour) inc Carney complex
Tetralogy of Fallot (Di George)
Gastrointestinal and hepatobiliary:
Malabsorption
Crohn's disease and ulcerative colitis
Cirrhosis, especially in primary biliary cirrhosis
Hepatopulmonary syndrome, a complication of cirrhosis
Others:
Hereditary nail clubbing; mutations in HPGD gene
SLE
Complex regional pain syndrome
Pachydermoperiostosis
Seen in hemiplegic limbs
HIV
If single digit think of subungual tumour
Hypertrophic (pulmonary) osteoarthropathy:
Thyroid acropachy
186
What should you look for in pts with yellow nails?
If all yellow think of Yellow nail syndrome;
Triad;
Yellow nails, Lung pathology, Lymphoedema;
Presents in 30s-50s
All 20 nails thick and yellow
Lower limb lymphoedema
Lungs - chronic bronchitis, bronchiectasis, sinusitis, pleural effusions
Can be RA, immunodeficiency or internal malignancies
Do full work up including ABPI, chest imaging, RF, blds and malignancy screen
Yellow colour is due to thickening but there may also be chronic infection (pseudomonas) - nails dont grow out but get thicker instead; cuticle is lost, can be onycholysis, onychomadesis
Rx - difficult
• Vitamin E 1200 IU/day or topical cream
• Pulse itraconazole
187
What nail changes are seen in HIV?
```
Clubbing
Transverse lines
Onychoshcizia
Leukonychia
Longitudinal melanoychia
Infection: dermatophytes, yeasts, HPV, HSV, crusted scabies
```
188
What is the likely cause of a single clubbed digit
subungual tumour
189
What is herpetic whitlow?
Primary inoculation of HSV into periungual fingertip
region
Important type of acute paronychia
Clear at first the blisters soon become purulent, may rupture and crust
Very painful and may take 3 weeks to resolve
antivirals help to settle
190
Who is at risk of periungual warts?
People who bite their nails or suck thumb
191
What are the treatments for warts on fingertips
```
Exclude SCC
Stop nail biting, thumb sucking etc
Do nothing
LN cryotherapy including 2mm margin for 5secs repeated 2-3 week intervals
Topical cantharidin
Topical immunotherapy with diphencyprone (DCP)
Keratolytics (Salicylic acid, lactic acid) under occlusion
Silver nitrate
Duct tape occlusion
5-FU
Imiquimod
Ablative laser CO2 or Erbium:YAG
Pulsed dye laser
C+C
Bleomycin
PDT
```
192
Which hair loss pts need a biopsy?
scarring alopecias
non-responding AA - to exclude lupus panniculitis and metastatic breast cancer
diffuse AA
moth eaten alopecia
193
T/F
| The outermost active part of a scarring alopecia provides the most informative histo
F
biopsy any area that has been present and active for at least 4 months and still has erythema - avoid the outer most inflammatory edge as less diagnostic and the inner as scar only
194
What causes someone to turn 'white overnight'?
Alopecia areata in greying hair - pigmented hairs are lost as it is a reaction to the pigment. White hairs spared
195
Why must you cut the hair and examine the scalp in acquired poliosis?
Can be melanoma with immune reaction to pigment - just like a halo naevus in an older person
196
What is DD for patchy hairloss?
Alopecia areata
Tinea capitis
Trichotillomania
Syphylis
