Dermatology Flashcards
Photo of nail pitting. Diagnosis is (what condition is associated with nail pits?):
a) psoriasis
b) fungal infection
c) traumatic
d) chemical reaction/exposure
e) ectodermal dysplasia
a) psoriasis
Can also see nail pitting with dermatitis and alopecia areata
Two pictures of rash consistent with Incontinentia Pigmenti. Which of the following is not associated with this problem:
a. alopecia
b. seizures
c. developmental delay
d. malignant changes in the skin
e. dental problems
d. malignant changes in the skin - nope, the skin lesions are benign
Neurocutaneous disorder - skin, dental and ocular abnormalities
What are 4 non-derm findings associated with incontinentia pigment?
Alopecia areata
seizures
intellectual disability
dental anomalies
cataracts
Girl that gets vesicles with sun exposure and hypopigmented flat scars with mild trauma. What medication is she likely to be taking? What is this condition called?
a. prednisone
b. naproxen
c. methotrexate
d. linolid
b. naproxen
Many drugs can cause photosensitivity reactions
People on NSAIDs for long periods of time (e.g. rheumatologic diseases) can develop pseudoporphyria (small hypo pigmented scars with mild trauma)
- need to stop NSAID ASAP as scarring can be permanent
A 9 year old boy has very swollen, dry, cracking lips and swollen tender gums. He is systemically
well. Which of the following conditions is this associated with:***
a. Eosinophilic gastroenteropathy
b. Contact dermatitis
c. Chronic candidal infection
d. Crohn’s disease
b. Contact dermatitis
(lip licking - not clear on why the gums are swollen; could also be description of herpetic gingivostomatitis)
Advantage of benzoyl peroxide?
a. Decrease P acnes resistance to antibiotic
b. Decrease duration for oral antibiotic
c. Inhibits androgen effect of sebum
d. Decrease need for antibiotic
a. Decrease P acnes resistance to antibiotic
How would you treat mild comedonal acne? How long do you need to treat to see effect? What are the anticipated side effects to counsel on?
Topical retinoid
6-8 weeks
Causes irritation and dryness; start using every 3 days, then every 2 days, then daily to build tolerance
How would you treat mild-moderate papulopustular acne?
topical retinoid plus benzoyl peroxide
OR
topical retinoid plus topical abx (clinda or eryrthro)
OR
topical retinoid plus BPO plus oral antibiotic (tetracycline)
*note benzoyl peroxide can bleach clothing
Combined OCP for women
How would you treat severe papulopustular or nodular/cystic acne?
topical retinoid plus benzoyl peroxide AND oral antibiotics
OR
isotretinoin (accutane) - 1mg/kg/day
A 14 y/o has been treated with Accutane for severe cystic acne. There have been a few case reports in the literature as well as some media attention to which of the following severe side effects:
a) Hallucinations
b) Cerebral thrombosis
c) Somnambulism
d) Major depression with suicide risk
e) Long term memory problems
d) Major depression with suicide risk
Girl with only blackheads. Best treatment?
a. Topical tretinoin
b. Topical benzoyl peroxide
c. Oral antibiotic
d. Accutane
a. Topical tretinoin
Teenage female presents with blackheads only, mild acne, what do you recommend?
a) Topical benzoyl peroxide gel
b) Topical retinoic acid
c) Accutane
d) Topical clindamycin
b) Topical retinoic acid
What are some examples of topical retinoic acids?
tretinoin
adapelene
tazarotene
Kid with acne on a medication now develops headaches; description consistent with benign
ICH. What is the most likely medication that she is on? (repeat from previous)
a. Minocycline
b. OCP
a. Minocycline
Describe the process of comedogenesis (4 factors in development of acne)
- Abnormal keratinization of follicular epithelium (impaction of keratinized cells)
- Increased sebum
- Proliferation of Propionibacterium in follicles
- Inflammation (free fatty acid formation by bacteria are inflammation causing)
Pustular acne in teenager. List 3 initial treatment options.
- topical retinoid plus benzoyl peroxide
- mild to moderate cleansing routine → not too aggressive
- consideration for topical antibiotics
- discontinue greasy makeup or hair products which can plug follicles
Child sucks on finger. Lesions on finger for 10 days. Finger hurts when mom touches it – picture of a finger with vesicles but also a central are of ulceration, some diffuse erythema of finger. We thought that this was herpetic whitlow, but not a very clear picture. What is your
management?
a) PO cephalexin
b) I & D
c) PO acyclovir
d) flamazine dressing
c) PO acyclovir
*best answer would be to do nothing
Acyclovir if immunosuppressed or severely infected; herpetic whitlow expected to spontaneously resolve in 2-3 weeks
Which of the following is true of molluscum:
a. it is pruritic
b. high infectivity
c. contagious for entire rash
d. lesions scar when healing
c. contagious for entire rash
Aggressively treating/picking at molluscum lesions can cause them to scar
What are some treatment options for molluscum contagiosum?
- do nothing
- curettage
- cantharidin
- cryotherapy
Photo of tinea capitus.
a) shave the child’s hair and treat with selenium shampoo daily for 14 days
b) treat the entire family with selenium shampoo daily for 14 days
c) treat with oral griseofulvin for 4-6 weeks
d) he should not attend school until treatment is complete
e) refer to a psychiatrist
c) treat with oral griseofulvin for 4-6 weeks
Treatment of tinea capitis?
a. Po lamisil
b. Topical fluconazole
c. Topical steroids
a. Po lamisil (terbinafine) - second line; griseofulvin is first line
What is the treatment for scabies?
5% permethrin applied to entire body from neck down. Leave cream on for 8-12 hours, then wash off. Repeat treatment in 7 days.
Treat the entire family and any caregivers for the child
A child is fully treated for scabies but 3 weeks later still has significant itching and discomfort. What is the cause and how is it treated?
Mite antigen remains in the skin and can cause a hypersensitivity reaction causing pruritus for days to weeks. Can treat with topical steroid.
A young boy has three circular patches of complete hair loss on his head. It is slightly itchy. His finger nails are normal. His mother had a similar episode when she was younger. What is the diagnosis?
a) Trichotillomania
b) alopecia areata
c) telogen effluvium
d) tinea capitis
d) tinea capitis
Picture of diffuse erythematous rash, confluent in areas, sparing inguinal folds, mucous membrane involvement. An 18 month old child has been on amoxicillin for 1 week for viral URTI symptoms. This rash develops on day 7, there is a positive Nikolsky’s sign and a large obvious bullae on one leg. What diagnosis is this consistent with:
a. Staphylococcal scalded skin syndrome
b. Eczema herpeticum
c. Toxic epidermal necrolysis
c. Toxic epidermal necrolysis
Nikolay sign: with slight pressure, skin wrinkles, slides laterally and separate from dermis
Child comes in with acute onset over 24 hours of fever and diffuse erythroderma. In your ED is hypotensive and complaining of myalgia. There is renal and liver dysfunction on bloodwork. What diagnosis is this most consistent with:
a. Stevens-Johnson syndrome
b. Kawasaki’s disease
c. Staphylococcal toxic shock
c. Staphylococcal toxic shock
Describe bullous and non-bullous impetigo
Non-bullous: honey crusted lesion, on face and extremities, caused by staph, sometimes GAS, no pain or surrounding erythema
Bullous: large, loose bullae, on face, extremities, butt, trunk and perineum, caused by toxin producing strain of staph,
Complications of bullous and non-bullous impetigo?
cellulitis, osteo, septic arthritis, pneumonia, sepsis
How is impetigo treated?
topical - mupirocin 2% TID x10-14 days
systemic - keflex x7-10 days
Kid with non-bullous impetigo a week ago now has hematuria. What’s happening?
Post strep GN
What is Gianotti-Crosti? What is it’s natural course?
immune reaction occurring 1 week after viral infection or immunizations
- main viruses: EBV, coxsackie, paraflu, Hep B
- crops of firm red papillose (may look like vesicles but there is no fluid inside)
- benign and self-resolves in 2 months
What are treatment options for genital warts?
25% podophyllin weekly
5% imiquimod 3x/week
Sinecatechins
What are management options for common warts?
Do nothing - 65% spontaneously resolve in 2 years
liquid nitrogen
laser
salicylic acid
daily imiquimod
What is the natural course of molluscum contagiosum? What is some anticipatory guidance for families to prevent transmission to others?
- self-limited
- average exacerbation lasts 6-9 months
- lesions can persist for years (new lesions forming as old ones resolve)
- avoid shared towels and baths while lesions present
- if swimming, cover exposed lesions with bandage
14 yo boy with some itchy lesions on R foot. Oral antibiotics and topical steroid creams not
helpful. Now the condition is worse. On exam there is interdigital fissuring and maceration with
erythema of the skin with peeling. What is the likely diagnosis (1). List 3 other causes on your
differential diagnosis
- Dx: tinea pedis
- Ddx: contact dermatitis
- atopic dermatitis
- juvenile plantar dermatitis
An 8 month old child is brought in with several small brownish nodules on his back and extremities. The parents have observed that when they touch the nodule, wheals develop around it, it it transiently becomes erythematous and their child starts to scratch it. What is the
diagnosis?
a) mastocytosis
b) neurofibromatosis
c) benign congenital nevi
a) mastocytosis
Gentle touch of the lesion triggers degranulation of mast cells and local histamine release causing a red wheal around the lesion (Darier sign)
What is the most common type of mastocytosis? When does it present? How is it managed?
urticaria pigmentosa
- present at birth, and develop more lesions over first few months
- spontaneously resolve, no need for treatment
Mean age of onset of neonatal acne? Treatment?
3 weeks, looks like teenage acne (closed comedones, papules and pustules on face and trunk)
- no treatment - disappears within 6 months
Picture showing rash with ppearance of militia rubra, timing of presentation and management?
AKA prickly heat rash
tiny red papules or papulovesicular lesions
- appear in first week of life
- found in intertriginous regions
- treat with air conditiong, cool soaks
Scaley rash that has pinpoint dot of blood visible when you pick off the scales. What is it?
psoriasis
Remember Koebner phenomenon - develop plaques at site of trauma
- List 3 treatment modalities for psoriasis.
- topical steroids mid potency BID; topical vitamin D (calcipotriene)
- immunosuppressants (methotrexate/cyclosporine)
- biologics (TNF alpha inhibitors - infliximab/etanercept)
You are seeing a 13 year old boy in your Emergency department. About one week ago he noticed an erythematous lesion, approximately 5 cm in diameter, on his lower back, which has since resolved. He now presents with a diffuse erythematous rash over his torso, which follows the skin cleavage lines.
a. What is the most likely diagnosis?
pityriasis rosea (description is of herald patch - 1-10cm)
5-10 days after herald patch, widespread rash over trunk and proximal limbs develops (oval/round, <1cm diameter, pink to brown, slightly raised)
In pityriasis rosea, how long will the rash last and how is it treated? Is it contagious?
Cause unknown - thought likely viral
- rash lasts for 2-12 weeks
- spontaneously resolves so treatment is symptomatic only (if scaling rash, use emollient, if pruritic use oral antihistamine, or may need topical steroids)
- can have post inflammatory hypo/hyperpigmentation which resolves
- not contagious
What is true of strawberry hemangiomas?
a. involution occurs after the second decade of life
b. they are usually not present at birth
c. there is never an indication to treat
b. they are usually not present at birth
When do infantile hemagiomas (aka strawberry) classically appear? When do they disappear?
first 2 weeks of life
- 60% gone by 5 years, 95% by 9 years
See a child with large segmental facial hemangioma. What are the components of PHACES syndrome?
Posterior fossa abnormalities
Hemangioma (large, V1 distribution)
Arterial abnormalities
Cardiac defects (coarctation)
Eye abnormalities (microphthalmia, glaucoma, optic nerve hypoplasia)
Sternal abnormalities (atresia)
Three initial investigations if you suspect PHACES in a child?
MRI brain (orbits, posterior fossa, optic nerve)
Echo
Ophtho consult
What is piebaldism? What syndrome is it associated with?
- hypopigmentation of skin, can affect anterior scalp also causing white forelock
- cutaneous sign of Waardenburg syndrome
List 5 features of Waardenburg syndrome
Hypo pigmentation of skin
White forelock
Heterochromia
Deafness
Limb anomalies
Hypopigmented area surrounding a hyperpigmented centre. What do you tell the parents? What is this?
a. this will spread to all over her trunk
b. spontaneous resolution
c. 1% chance of progression to melanoma
d. will become a neurofibroma
b. spontaneous resolution
Halo nevus:
melanocytic nevus with surrounding halo of hypo pigmentation; skin is normal after is regression and no concern in kids for malignant transformation
7 year old boy with query Neurofibromatosis type 1. (1) how many clinical criteria do you need for diagnosis (2) what are four clinical criteria for NF-1
- minumum 2/7 clinical criteria for diagnosis
- 6+ CALMs (>5mm for prepubertal, >15mm for pubertal)
- 2+ Lisch nodules (iris hamartomas)
- optic nerve glioma
- 2+ neurofibroma (nodules under skin)
- axillary/inguinal freckling
- boney lesions (sphenoid dysplasia or cortical thinning of long bones)
- first degree relative with NF1
2 year old with diffuse atopic dermatitis. He is compliant with steroid treatment but is not improving.
What topical agent could be the next line?
a. Methotrexate
b. Tar
c. Tacrolimus topical
d. Cyclosporine
c. Tacrolimus topical
Topical calcineurin inhibitor (moderate to severe AD in kids >2 years not responding to steroids)
Baby with bright red peri-anal dermatitis
a) Strep
b) Contact
c) Candida
d) Sexual abuse
b) Contact (diaper dermatitis)
Picture of infant who is 2 months old with a rash on cheeks – more irritable than usual, otherwise well. Rash on legs is crusting. Identify. 3 different classes of medications and routes .
Thinking atopic dermatitis:
- topical steroids
- topical calcineurin inhibitors
- tar preparations
- immunosuppressants (oral - cyclosporine, MTX)
Child with trisomy 21. 3 discrete round completely hairless areas on the scalp. No other findings. What is the most likely diagnosis? What will you tell mom is the natural history of this problem?
Alopecia areata
(increased incidence in T21 - 5-10%)
- spontaneous resolution is common, but relapses can occur
Picture of a child with a red erythematous nodule in neck at midline.(location difficult to see b/c poor picture). What is your initial treatment. ***
- Abx
- I & D
- resection
- U/S
Probably need more info, but U/S or Abx
Thinking thyroglossal duct cyst that is infected so would need treatment with antibiotics. Once infection resolved should be resected. No I&D as can seed. U/S is best initial imaging modality
Pictures of a 4 week infant with a papular, pustular rash, on erythematous base on face and trunk. (upper chest) Well child. (first picture of face, second of the face and trunk –What is your diagnosis? How do you manage this problem?
Erythema toxicum neonatorum versus neonatal acne (*probably neonatal acne given timing of presentation)
- note that neonatal acne develops at a mean age of 3 weeks and erythema toxicum appears on day 2-5 of life; course is brief (resolves in 14 days) and no treatment is required
- neonatal acne also requires no treatment and resolves in first 6 months
Picture of a 7 year old boy’s thigh, linear vesicles with some excoriation. He comes to your office, in July, with a rash on his left thigh, It is itchy and has seemed to spread where he scratches.
(1) What is your diagnosis
Poison ivy (aka allergic contact dermatitis)
- Type IV delayed hypersensitivity reaction
- rash appears 48 hours after exposure in a sensitized individual
What is the treatment of poison ivy?
- wash skin and other items that may have been in contact with plant
- systemic antihistamines for itch
- mild-moderate strength topical steroids
- topical pramocaine (topical anesthetic) for itch
What are common triggers for EM, SJS/TEN?
Delayed-type hypersensitivity reaction; most common causes include:
- Medications: antiepileptics, sulfonamides, beta-lactams, quinolones, NSAIDs
- Infections: Mycoplasma pneumoniae, HSV 1 and 2
- Less commonly, may be malignancy-related or idiopathic
Incontinentia Pigmenti
- XLD inheritance
- Mutation in IKBKG - males usually fetal lethal
- Classic skin findings along the lines of Blaschko
- Blistering rash in infancy
- Swirling macular hyperpigmentation in childhood
- Linear hypopigmentation in adulthood
- Diagnosis by molecular sequencing of IKBKG
- Evaluation:
- Surveillance for seizures and retinal detachment
- Management:
- Multidisciplinary = early intervention, dental, ophthalmology, and neurology
Criteria for Referral to Burn Centre
Fluorosis
- Mottled enamel from systemic fluoride consumption more than 0.05mg/kg/day during enamel formation
- Can be due to being in high area of fluoride in drinking water, swallowing fluoridated toothpaste or inapprop fluoride supp (shouldn’t give more than 120mg)
- Excessive fluoride during enamel formation = lacy white patches to severe brownish discolouration and hypoplasia
DDX:
- neonatal hyperbili (blue-black on primary teeth)
- porphyria (red-brown)
- tetracyclines (brown-yellow and hypoplasia)
What are differences between EM/SJS/TEN?
EM = benign, self-limiting (NOT derm emergency)
- target lesions with three colour zones
- can have oral lesions (usually with HSV ulcers)
- usually appear within 24-72 hr and can last for 2 weeks
- can have recurrence, esp with HSV
SJS/TEN = spectrum of severity, can be rapid progressive and life-threatening
- erythematous/purpuric macules or atypical target lesions progressing to flaccid bullae that desquamate
- affects palms and soles
- MUST have mucosal involvement (oral, genital, ocular)
- SJS = <10% total BSA
- SJS/TEN overlap = 10-30% BSA
- TEN = >30% BSA
- prodrome of fever, myalgias, sore throat, HA
- eruption 1-3 weeks after drug initiation but can be up to 8 weeks after
- complications (sepsis/shock, ophthalmic, pulmonary, GI, GU involvement)
What is Epidermolysis bullosa?
Epidermolysis bullosa:
- rare group of inherited disorders due to defects in structural proteins in the skin with poor skin integrity (leads to widespread blistering of the skin)
- some are autosomal dominant so should have FMHx
- Dx made by skin biopsy sampes for immunofluorescence or whole exome sequencing
- DDX: bullous mastocytosis, neonatal HSV, bullous impetigo, incontinentia pigmenti
- Treatment = supportive care (protection from friction or heat, non-stick dressings to open areas, bleach baths and dilute vinegar baths if overgrowth of pseudomonas or staph, pain and pruritis management and nutritional support)
What is associated with Hypohidrotic Ectodermal Dysplasia?
- Hypotrichosis (area with never any hair growth)
- Hypohidrosis (not sweating)
- Dental deformities (conical teeth)
Also: frontal bossing and square foreheads, pointy ears and prominent chin, minimal /mild nail changes and alopecia
Guttate psoriasis:
- psoriasis associated with step infections (oropharynx or perianal) or other URTIs
Lichen sclerosis
- autoimmune condition
- complications of dysuria, labial obliteraton, constipation
- can lead to SCC
- Treat with high potency topical steroids
What is this associated with?
Halo nevus
- associated with increased risk of vitiligo
- in adults is assoc with melanoma but not in children
Congenital melanocytic nevus on face: what is the risk?
melanocytosis of the leptomeninges
