Finger and Toenails, Scalp and Hair Flashcards
1
Q
Define nail plate
A
Keratinized structure which continues growing throughout life
2
Q
Define lateral nail folds
A
Cutaneous folds providing lateral borders to the nail
3
Q
Define proximal nail fold
A
Cutaneous fold providing the visible proximal border of the nail
4
Q
Define cuticle (eponychium)
A
Extends from the proximal nail fold and adhering to nail plate
5
Q
Define nail matrix (nail root)
A
Nail factory, beneath the proximal nail fold
6
Q
Define lunula (half moon)
A
Convex margin of the matrix seen through the nail
7
Q
Define nail bed
A
Vascular bed upon which the nail rests, extending from the lunula to the hyponychium
8
Q
Define hyponychium
A
Cutaneous margin underlying free nail
9
Q
Define onychomadesis
A
- Complete separation of the nail plate from the bed
* Full but temporary arrest of growth of nail matrix
10
Q
5 causes of oncyhomadesis
A
- Trauma (i.e. manicure, onychotillomania)
- Dermatologic diseases (i.e. eczema, erythroderma)
- Systemic conditions
- High fever
- Viral illness
11
Q
Management of onychomadesis
A
Reassurance (nail will grow back)
12
Q
Define trachyonychia
A
Nail roughness and opacity due to excessive longitudinal ridging
13
Q
5 causes of trachyonychia
A
- Idiopathic
- Alopecia areata
- Psoriasis
- Dermatitis
- Lichen planus
NOTE: May occur before apparition of other signs of related disease, so should observe them to exclude these and THEN label as idiopathic
14
Q
4 points of management for trachyonychia
A
- Spontaneous improvement if possible
- Keep nails short with frequent filing
- Can use potent topical corticosteroid
- Oral biotin
15
Q
Define nail pitting
A
Common disorder where punctate depressions appear on nail plate
16
Q
4 associated conditions to nail pitting
A
- Psoriasis
- Eczema
- Alopecia areata
- Trauma
17
Q
4 points of management for nail pitting
A
- Look for symptoms and signs of possible associated disease
- If nothing, follow up to see if later development
- Observation
- Potent topical corticosteroid
18
Q
Define acute paronychia
A
Painful, erythematous indurated swelling of nail folds with purulent draining developing over a few hours
19
Q
Usual cause of acute paronychia
A
Staphylococcus aureus
20
Q
Management of acute paronychia
A
- Oral antibiotics with gram-positive coverage against S. aureus
- If progression to abscess –> drain promptly
21
Q
Define chronic paronychia
A
Non-purulent, glistening erythema with nail dystrophy
22
Q
Cause of chronic paronychia
A
Candida and irritation caused by saliva (not uncommon in thumb suckers)
23
Q
Define herpetic whitlow
A
HSV 1 or 2 infection of the fingertip and perionychium presenting with pain, edema and erythema
NOTE: may be confused with acute bacterial paronychia
24
Q
3 points of managements for herpetic whitlow
A
- Warm compress
- Topical antibiotic to prevent secondary bacterial infection
- Oral acyclovir can shorten duration???
25
Define melanonychia
Tan, brown or black pigmented band along the length of nail
26
Conditions associated with melanonychia
Nail matrix nevus or lentigo
| Early subungual melanoma rare but reported
27
5 alerting signs in the event of melanonychia
* In adults
* Non-uniform color
* Change in color or width
* WHen the edge becomes blurred
* Familial history of melanoma
28
Define racial melanonychia
WHen the pigmented band involves several nails; more common in darker skin phototypes
29
Prevalence of racial melanonychia
77% of young African-American adults and almost 100% of those older than 50 years of age
30
Define drug-induced melanonychia
When there are multiple pigmented bands on several nails, usually in the situations of chemotherapy, antiretroviral and antimalaria treatments
31
4 consequences of periungual warts
* Embarrassment
* Pain
* Nail deformity
* Keratolysis
32
Management of periungual warts
Cryotherapy
| Avoid nail biting and cuticle picking
33
Define onychomycosis
Fungal infection of nail unit
NOTE: Look for tinea pedia in patients and the family
34
Define distal subungual onychomycosis
Fungal invasion of nail bed and inferior portion of nail plate
35
3 symptoms of distal subungual onychomychosis
* Onycholysis
* Subungual hyperkeratosis
* Yellow brown discoloration
36
Define white superficial onychomycosis
Superficial infection of nail plate
37
Describe the manifestation of white superficial onychomycosis
Well demarcated whitish, opaque, friable plaques on dorsal nail plate
38
How to culture the fungus from white superficial onychomycosis
1) Scrape the debris under the nail
2) Send it off in a sterile container to the lab
3) Is usually branched septate fungal hyphae
39
4 points of diagnosis for onychomycosis
* KOH discoloration
* Periodic acid-Schiff (PAS) stain
* Recommended to do diagnostic tests
* Consider alternative causes of nail changes
40
3 treatments for onychomycosis
```
• Oral lamisil (60% success)
- 12 weeks for toes
- 6 weeks for fingers
• CBC and LFT base (every month)
• Penlac (Ciclopirox) = 20% success
- 48 weeks
```
41
5 ways to reduce relapse rate in the event of onychomycosis
* Don't share shoes
* No poorly fitted shoes
* Use antifungal sprays or powders in shoes and socks
* Avoid going barefoot at all
* Discard old shoes
42
Define hair follicle
A tube-like depression, or pocket in the skin or scalp that encases the hair root
43
Define hair bulb
A thickened, club-shaped structure that forms the lower part of the hair root
44
Give a brief description of how the hair shaft is made
Matrix cells in hair bulb proliferate and differentiate to make the hair shaft during the anagen
45
Time length of anagen
1000 days
46
Define anagen
Matrix cells grow, divide and become keratinized to form the growing hair
47
Define catagen
Matrix proliferating cells abruptly cease proliferating so that hair bulb involutes and regresses
48
Define telogen
Club-shaped proximal end shed from the hair follicle
49
Time length of telogen
100 days
50
2 categorizations of alopecia
Localized vs. diffuse
Cicatricial vs. non-cicatricial
51
Define cicatricial alopecia
* Lack of follicular ostia
| * Shiny atrophic skin
52
Define alopecia areata
* Recurrent non-scarring, non-scaly type of hair loss
| * One or more alopetic plaque
53
Define exclamation point hairs
* Short broken hairs
| * Narrower proximal end compared to distal end
54
6 poor prognostic factors in the event of alopecia
* Young age
* Atopy
* Extensive involvement
* Pitting
* Ophiasis
* Recurrence
55
Define alopecia totalis
100% hair loss on the scalp
56
Prevalence of pitting in alopecia patients
6.8 to 49.4% of patients
57
Define ophiasis
Pattern of hair loss that is localized to the sides and lower back of the scalp
58
Define tinea capitis
Infection of the scalp with a dermatophyte fungi
59
Demographics of tinea capitis
Pre-school and school aged children
| Black children
60
Define the seborrheic type of tinea capitis
Scaling of scalp, often without noticeable hair loss
61
Define tinea capitis with black dot
Small black dots (stubs of broken hairs) within areas of alopecia
62
Define tinea capitis kerion
A boggy inflammatory mass surrounded by follicular pustules due to a hypersensitivity reaction to the fungal infection
63
2 potential accompanying symptoms of tinea capitis kerion
Fever
| Local lymphadenopathy
64
3 potential misdiagnoses in the event of tinea capitis kerion
Impetigo
Cellulitis
Abscess
65
Define grey patch tinea capitis
Circular patches of alopecia with marked scaling with broken hair close to the surface
66
2 causes of tinea capitis
T. tonsurans
| M. canis
67
How is T. tonsurans spread?
From one person to another (anthropophilic)
| Remains viable on combs, hairbrushes and other fomites for long periods of time
68
How is M. canis spread?
Zoophilic (grows naturally on an animal) so spreads to human by contact with an infected kitten or rarely an older cat or dog
69
How to diagnose tinea capitis
Scraping --> KOH and culture
70
3 treatment points for tinea capitis
* Oral lamisil for 4 - 6 weeks
* Loprox lotion BID during the Tx period
* Topical therapy reduce infectivity
71
4 preventive measures to prevent the spread of tinea capitis
* Treat the close contacts if affected
* Clean brushes and combs in bleach solution
* No sharing of hair brushes, combs and hats
* Using the Nizoral shampoo for all the family to prevent reinfection
72
Define scalp psoriasis
Discrete erythematous plaques covered by a silver-gray scale. Affects hair margins; pruritis possible.
NOTE: No alopecia
73
Define trichotillomania
Habitual, compulsive plucking of hair
74
Consequence of trichotillomania
A well-defined area of hair loss with shortened, broken-off hairs of different lengths (frontotemporal or parietotemporal)
An obsessive compulsive disorder
75
Treatment for trichotillomania
Habit should be stopped --> psychiatric evaluation
76
What should be ruled out if localized non-cicatricial alopecia presents as scaly
Tinea capitis
77
What is the diagnosis if the patient presents with localized non cicatricial alopecia that is not scaly and with exclamation mark hair
Alopecia areata
78
What is the diagnosis if the patients presents with non-cicatricial alopecia that is not scaly and with shortened, broken-off hairs of different lengths
Trichotillomania
79
Define androgenetic alopecia
Genetically determined sensitivity of scalp hair follicles to adult levels of androgens --> loss of hair in frontotemporal and vertex area
80
Prevalence of androgenetic alopecia
Common disorder affecting roughly 50% of men and women older than 40 years
81
Describe the progression of androgenetic alopecia in men
1) Bitemporal recession of the frontal hairline
2) Diffuse thinning over the vertex of scalp
3) Bald patch progressively enlarges --> eventually joins receding frontal hairline
4) Just marginal parietal and occipital hair left
82
Describe the progression of androgenetic alopecia in women
Diffuse central thinning of the crown with preservation of the frontal hair line
83
Metabolite with a dominant role in androgenetic alopecia
DHT (testosterone metabolite)
84
What regulates DHT production
5-alpha reductase (found in hair follicles!)
85
Describe the levels of 5-alpha reductase in androgenetic alopecia
Higher levels of 5-alpha reductase --> more androgen receptors
86
Effect of DHT on hair
Shorten the growth phase of the hair from a usual duration of 3 - 6 years to just weeks or months --> miniaturisation of the follicles and lower production and finer anagen hairs
87
2 drugs to treat androgenetic alopecia
Minoxidil
| Finasteride
88
Describe the supposed effects of minoxidil
Lengthen duration of anagen phase
May increase blood supply to follicle
At least 4 months to have effect
89
Consequence of discontinuing minoxidil
Rapid reversion to the pretreatment balding pattern
90
Define finasteride
5-alpha reductage type 2 inhibitor
91
Effect of finasteride
Diminish the progression of androgenetic alopecia and may stimulate new regrowth
92
Define telogen effluvium
Generalized and diffuse hair loss (not normally permanent)
| Increased percentage of hair follicles are in a resting phase than would normally be expected
93
6 causes of telogen effluvium
* Hypo- or hyperthyroidism
* Postpartum
* Dietary insufficiency
* Medication
* Surgery
* Systemic illness
94
Timeline of telogen effluvium
* Loss within 3 - 5 weeks of inciting signal
* Shedding continues for about 3 - 4 months after removal of cause
* Hair density may take 6 - 12 months to return to baseline
