Define macule and give an example
- flat spot less than 1 cm
- freckles
Define patch adn give an example
- flat spot greater than 1cm
- port wine stain
Define papule and give 3 examples
- solid elevated palpable lesion less than 1cm
- wart, acne, lichen planus
Define plaque and give an example
- solid flat topped elevate palpable lesion greater than 1cm
- psoriatic patch
Define nodule and give 2 examples
- palpable solid lesion greater than 1cm (not flat topped)
- small lipoma, erythema nodosum
Define vesicle and give 2 examples
- elevated, circumscribed lesion less than 5mm containing fluid
- small blister
- chickenpox, HSV
Define bulla and give 2 examples
- elevated, circumscribed, fluid filled lesion greater than 5mm
- large blister
- contact dermatitis, pemphigus
Define wheal and give an example
- itchy transiently edematous area
- allergic reaction
General definition of vitiligo
depigmentation of unknown etiology
Vitiligo is often associated with
autoimmune conditions like pernicious anemai and hypothyroidism
Patients with vitiligo may have antibodies to
melanin
Biopsy in vitiligo may show
absense of melanocytes
Puritis is often a clue to these diseases:
- obstructive biliary disease
- uremia
- polycythemia rubra vera
- atopic dermatitis
- scabies
- lichen planus
Puritis after a warm shower may be a clue to
polycythemia rubra vera
Pruritis with obstructive biliary disease is classically ________
primary biliatry cirrhosis
The most common form of contact dermatitis in women
nickel dermatitis (jewlery)
Contact dermatitis is usually this type of reaction
type IV hypersensitivity
List three classic offending agents for contact dermatitis
nickel, deoderant, poison ivy
Describe the rash of contact dermatitis
- well circumscribed
- only in areas of exposure
- red
- itchy
- often with vesicles or bullae
Testing and treatment of contact dermatitis
- patch test
- avoid offending agent
Major features of atopic dermatitis
- chronic
- begins in 1st year of life
- rash is red, itchy, weeping on head and arms sometime diaper area
Main symptoms of atopic dermatitis
itching and skin breaks lead to possible infection risk
Treatment of atopic dermatitis
- avoid dry soaps
- antihistamines
- topical steroids
What is blepharitis?
seborrheic dermatitis of the eyelid
3 common subtypes of seborrheic dermatitis
- cradle cap
- dandruff- blepharitis
Classic findings of seborrheic dermatitis
scaling skin on scalp and eyelids
Treatment of seborrheic dermatitis
dandrum shampoo (selenium sulfide)
fungal infection on the trunk is called
tinea corporis
describe the lesion of tinea corporis
- red
- ring-shaped
- raised borders
- clear centrally while they expand peripherally
fungal infection on the feet is called
tinea pedis
describe the lesion of tinea pedis
- macerated
- scaling web spaces
- itches
thicked distorted toenails are often
onychomycosis
Most important part of treatment for tinea pedis
good foot hygeine
fungal infection of the nails is called
tinea unguium or onychomycosis
fungal infection of the scalp is called
tinea capitis
is tinea capitis contagious?
yes, very
an inflammed boggy granuloma of the scalp is called
kerion
Describe the characteristics of tinea capitis
- sclay patches of hair loss
- boggy granulomas (kerions)
technical name for jock itch and what type of infection
- tinea cruris (crural folds)
- fungal infection
Most skin fungal infections are caused by
Trichophytan species
How do you confirm a tinea infection?
scraping of sking with KOH prep or by culture
Pharmacologic treatment of tinea infections
- tinea capitis: oral agent
- onychomycosis: oral agent
- others can be treated with topical and/or oral
Typical oral and topical treatments for tinea
- terbinafine, fluconazole
- topical imidazoles (miconazole, clotrimazole, keotoconazole)
Differentiation of causative organism in tinea capitus
- if hair fluoresces under the wood’s lamp = microsporum
- otherwise = trichophyton
Physical appearance of thrush
white patches on tongue or buccal mucosa that can be scraped off
When is candial infection considered normal/non-concerning
- children
- vulvovaginitis in women esp when pregnant or on antibiotics
Thrush without good explanation should prompt consideration of…
- immunodeficiency
- diabetes
Treatment of trush
- topical with nystatin or imidazoles
- systemic for resitant disease
Systemic therapies for thrush
- nystatin
- ketoconazole
Multiple patches of various size and color on the torso in a young adult =
tinea versicolor
Characteristics of tinea versicolor
- young adults
- multiple patches of various size and color on the torso
- patches fail to tan (often noted in summer)
Diangosis of tinea versicolor
- clinical
- KOH prep
Treatment of tinea versicolor
- selenium sulfide shampoo
- topical imidazoles
Classic areas for scabies
- finger web spaces
- flexor surfaces of the wrist
Treatment of scabies
- permethrin
- technically lidocaine can be used but has a risk of neurotoxicity especially in young children
- remember to treat all contacts
Pediculosis =
lice
The technical name for lice is
pediculosis
head lice is called
pediculus capitis
body lice is called
pediculus corporis
pubic lice is called
phthirus pubis
Treatment of lice
- permethrin
Genital warts that are associated with cancer
HPV 16 and 18 are associated with cervical cancer
Warts are most commonly seen ________
in older children, on the fingers
Are warts infectious?
yes
Warts are caused by
human papillomavirus
Typical treatments for warts
- salicylic acid
- liquid nitrogen
- curettage
Scabies is caused by
sarcoptes scabei
Halmark lesion of scabies
burrow on:
- finger web spaces
- flexor surfaces of the wrist
Treatment of scabies
Permethrin
- be sure to treat contacts
Pediculosis =
lice
Lice is also called
pediculosis
Pediculus capitis is common in
school children
Pediculus corporis usually involves
poor hygeine
Phthirus pubis is
sexually transmitted lice
Diagnosis of lice is made by
seeing lice on hair shafts
Treatment of lice
- permethrin
- decontaminate combs, hats, sheet, clothing
Warts are caused by
human papillomarvirus (HPV)
Warts in children are often seen
on the hands
Genital warts are caused by
HPV 16 and 18
Genital warts are associated with
cervical cancer
Treatment of warts
- salicylic acid
- liquid nitrogen
- curettage
molluscum contagiosum is a
poxvirus
Molluscum contagiosum is common in
- children
- STD
- don’t forget autoinnoculation
Appearance of mollusceum contagiosum
- skin-colored
- smooth
- waxy papules
- central depression (umbilitated)
A 0.5cm waxy skin colored umbilicated papule =
molluscum contagiosum
Characteristic pathologic appearance of molluscum contagiousum
inclusion bodies
Treatment of molluscum contagiousum
- freezing
- curettage
5 common “medical” descriptions of acne
- comedones (whiteheads/blackheads)
- papules
- pustules
- inflammed nodules
- superficial pus-filled cysts
Gland that gets blocked in acne
pilosebaceous glands
Organism often involved in acne
Propionibacterium acnes
Acne is NOT related to
- exercise
- sex
- masturbation
Progression of treatment options for acne
- topical benzoyl peroxide
- topical clindamycin
- oral tetracycline or erthromycin
- topical tretinoin
- oral isotretinoin
Antibiotic for eradication of propionibacterium acnes
erythromycin
Side effects of oral isotretinoin
- dry skin
- dry mucosae
- muscle and joint pain
- abnormal LFTs
This looks like acne but usually starts in middle age
Rosacea
Rhinophyma =
bulbous red nose
Bulbous red nose in rosacea =
rhinophyma
Rosacea often also has
rhinophyma and blepharitis
Pathogenesis of rosacea
unknown (but not related to diet)
Treatment of rosacea
- topical metronidazole
- oral tetracycline
Signs of virilization
- hirsutism
- deepening voice
- clitoromegaly
- frontal balding
Most common cause of virilization
idiopathic
Hirsutism is often a sign of
virilization
More common causes of hirsutism
- androgen secreting ovarian tumor
- corticosteroids
- Cushing syndrome
- Stein-Leventhal syndrome
- minoxidil
- phenytoin
- other drugs
Stein-Leventhal syndrome =
polycystic ovarian disease
Psychiatric disorder where one pulls out hair
trichotillomania
trichotillomania =
pathological hair pulling
What is alopecia areata
- form of baldness
- idiopathic
- associated with antimicrosomal and other antibodies
- seen with lupus, syphilis, after chemo
Key features of male-pattern baldness
- benign
- requires androgen expression
- considered genetic
Classic lesions of psoriasis
- dry
- NOT pruritic
- well-circumscribed
- silvery
- scaling
- papules/plaques
- on extensor surfaces/scalp
A dry well-circumscribed, silvery, scaling papule on the scalp or extensor surfaces =
psoriasis
Family history for psoriasis
often positive
Psoriatic arthritis is RF
negative
People with psoriasis often have nails that are
pitted
Psoriasis is most often seen in
- whites
- onset early adulthood
General treatment of psoriasis
- UV light
- lubricants
- topical corticosteroids
- keratolytics
Examples of keratolytics (such as in treatment of psoriasis)
- coal tar
- slicylic acid
- anthralin
Age for pityriasis rosea
adults
Scaly slightly erythematous ring-shaped lesion on the trunk =
“hearld patch” of pityriasis rosea
Lesions of pityriasis rosea
- scaly red itchy ring shaped
- starts with hearld patch on trunk
- 1 weeks later many more appear
- follow langerhan’s skin cleavage lines
- often in “Christmas tree”
Rash with “Christmas tree” pattern
pityriasis rosea
General course of pityriasis rosea
spontaneously remits in 1 month
Ddx of pityriasis rosea
syphilis
Treatment of pityriasis rosea
reassurance
Features of lichen planus:
“The 4 P’s”:
- pruritic
- purple
- polygonal papules
pruritic purple polygonal papules =
lichen planus
Classic location of lichen planus
wrists and/or ankles
Typical course and treatment of lichen planus
- self-limited and resolves within a few years
- symptomatic treatment for itching
2 major drug causes of photosensitivity
- tetracycline
- phenothiazines
Classic lesions of erythema multiforme
- target of iris lesions
Infection that can cause erythema multiforme
- herpes
Erythema multiforme is usually caused by
- drugs
- infections
Characteristic feature of Stevens-Johnson syndrome
Erythema multiforme with mucosal involvement
Treatment of erythema multiforme
supportive
Typical description of erythema nodosum
- inflammatory
- subcutaneous tissue and sin
- tender red nodule
Classic location of erythema nodosum
- shins (pre-tibial)
Classic causes of erythema nodosum
- unknown
- streptococcal
- sarcoidosis
- coccidiomycosis
- ulcerative colitis
pemphigus vulgaris is an _______ disease
autoimmune
Typical age for pemphigus vulgaris
middle and older age
Typical lesions of pemphigus vulgaris
- multiple bullae starting with oral mucosa
- blisters slough and leave raw skin
Multiple bullae starting with oral mucosa, blisters then slough =
pemphigus vulgaris
Biopsy of pemphigus vulgaris shows
(stain for antibody)
- lacelike/fishnet immunofluoresence
Treatment of pemphigus vulgaris
corticosteroids
Death from pemphigus vulgaris is often due to
- secondary skin infection
- fluid loss
Compare biopsy results of pemphigus vulgaris vs bullous pemphigoid
- lacelike/fishnet = vulgaris
- linear = pemphigoid
Dermatitis herpetiformis is a tip-off for
gluten sensitivity (celiac disease)
Pathology of dermatitis herpetiformis
IgA deposits (even in unaffected areas)
Pruritis vesicles, papules and wheals on extensor aspects of elbows and knees +/- face/neck =
dermatitis herpetiformis
Treatment of dermatitis herpetiformis
gluten-free diet
3 major causes of new onset excessive perspiration
- hyperthyroidism
- pheochromocytoma
- hypoglycemia
Reasons to bioby/excise a mole
- enlarges
- irregular borders
- darkens/inflammed
- changes color
- bleeds
- itches
- painful
Characteristics of dysplastic nevus syndrome
- genetic
- often >100 nevi
- family history of melanoma
Keratocanthoma often mimics
squamous cell skin cancer
Classic description/course of keratocanthoma
- rapid onset
- grows to full size in 1-2 months
- fleshy lesion with central crater with keratinous material
Classic locations for keloid
upper back, chest, deltoid
Classic appearance of basal cell skin cancer
- shiny purple
- grows slowly
- umbilicated center
- often later ulcerates
- peripheral telangeictasias
Shiny purples slow growing lesion =
basal cell cancer
Metastatic tendency of basal cell carcinoma
almost never
Risks for basal cell carcinoma
- sunlight
- light skinned
Features of actinic keratoses
hard, sharp, red, scaly
Hard sharp red scaly lesion in sun exposed area =
actinic keratoses
If a burn scar becomes nodular, warty or ulcerated, think_____
squamous cell cancer
Squamous cell cancer may have pre-cursor _____ lesions
actinic keratoses
Squamous cell skin cancer is also known as
Bowen disease
Actinic keratoses is precursor lesion of
squamous cell cancer
Best and worst prognostic types in melanoma
- best: superficial spreading
- worst: nodular
Black dots on palms, soles or under nails =
melanoma
Prognosis in melanoma is related to
vertical depth on invasion
Kaposi sarcoma is classically associated with
AIDS
Paget disease of the nipple, must rule out
breast adenocarcinoma
Classic nutritional cause of stomatitis
- B-complex vitamins
- Vitamin C
What are the main B-complex vitamins (deficiency may cause stomatitis)
- riboflavin
- niacin
- pyridoxine