Derm SAS/Review Flashcards
What are the signs and symptoms of DRESS?
Drug Reaction with Eosinophilia and Systemic Symptoms
- A drug-induced hypersensitivity reaction
-
Skin eruption with systemic symptoms and internal organ invovlement
- Macular exanthem
- Centrofacial swelling
- Fever
- Malaise
- Lymphadeonpathy
- Involvement of other organs
- >70% of patients have eosinophilia
What is the importance of filaggrin breakdown products in skin function?
Filaggrin is an important protein in the skin’s barrier function
Breakdown products normally keep skin hydrated
Non-functioning or reduced filaggrin is associated with atopic dermatitis and ichthyoses
Which cells in the epidermis function as mechanoreceptors?
Merkel cells
Which inflammatory myopathy is most strongly associated with malignancy?
Dermatomyositis (adult presentation)
Juvenile DM is not associated with malignancy
Describe the presentation of subacute cutaneous lupus
- Scaling, annular pink papules and plaques
- No scarring
- Low tendency for systemic disease
- Associated with Anti-SSA (Ro)
- This antibody is also implicated in neonatal lupus
- Take a complete drug history!
The discovery of ovarian cancer 6 months into the development of weakness would suggest
A: PM
B: DM
C: IBM
D: None of the above
B: DM
How does UVA light affect the skin?
Which skin cancer is it associated with?
- 320-400 nm
- Contributes to tanning and photoaging
- -> Squamous cell carcinoma
- Penetrates clouds and windows
- Used in tanning beds
A child presents with multiple cafe-au-lait spots and lisch nodules on the iris.
What gene is likely mutated?
What is the prognosis?
Deletion of neurofibromin, a tumor suppressor gene
- -> RAS activation
- Prognosis
- Optic gliomas, dermal neurofibromas may become malignant
- Learning and speech issues
What is the treatment for vitiligo?
- Phototherapy
- Topical steroids
- Topical immunosuppressants
- Tacrolimus
- Lasar therapy
- Depigmentation
- For widespread vitiligo, option may be to depigement the pigmented areas rather than try to restore pigmentation to the affected areas
What condition is caused by antibodies that target Keratin 5 and Keratin 14?
Epidermolysis bullosa simplex
- Genetic disease
- Presents in younger patients
- Results in fragile blisters
- Cleavage of basal layer keratinocytes from each other
What is the pathogenesis of this legion?
This is a keloid - results from abnormal wound healing
- Normal wound healing involves collagen production and degradation
- In keloids, there is an imbalance, leading to excessive collagen production, and less degradation
- This allows the scar to grow out of control in all directions
A patient presents with new-onset alopecia areata.
What is the most important hormone to check?
Thyroid Stimulating Hormone
- Thyroid disorders are the most common other autoimmune disorder in patients with alopecia ariata
- Also look for vitiligo, diabetes
Autoantibodies against the hemidesmosome lead to which skin condition?
Bullous pemphigoid (pictured)
- -> Separation of the basal keratinocytes from the basement membrane
- -> Tense bullae
Note: Autoantibodies against desmosomes -> Pemphigus vulgaris, characterized by non-tense blisters and erosions due to separation of keratinocytes from each other
Which appendage of the skin is labeled by c?
Sweat glands
38-year-old man who presents with one month of small blisters on his feet. They are slightly itchy
KOH shows branched, septated hypae.
What is the most likely diagnosis?
Tinia pedis
“Athlete’s foot”
What causes Hand, Foot, Mouth disease?
Describe the clinical presentation
Coxsackie virus A-16 or Enterovirus 71
- Fever
- Ulcerovesicular stromatitis
- Acral erythematous vesicles
- Buttock lesions
Psoriasis is best characterized as :
- Infectious disorder of the skin characterized by sensitivity to bacterial pathogens
- An inflammatory disorder characterized by activation of T-cells and overexpression or certain cytokines
- An autoimmune condition caused by immune cells attacking cell nuclear proteins
- A skin limited condition that never affects other organ systems
b. An inflammatory disorder characterized by activation of T-cells and overexpression or certain cytokines
(TNF-alpha, IL-17, IL-23)
Medications that block TNF-alpha, IL-23, and/or IL-17 would be helpful in treating which skin condition?
Psoriasis
Use if disease is widespread
Topical corticosteroids for local disease
A patient presents with several linearly arranged pruritic edematous excoriated 5mm papules on both of her legs. These seem to come in crops. It is winter and she has no known exposure to mosquitoes. Her husband may have had a few similar lesions. You recommend:
A. Use of DEET when she goes outdoors
B. Treatment for shingles
C. Professional extermination
D. She should get a new mattress
C. Professional extermination
Bedbugs! Must be professionally esterminated
What is the treatment for IgA vasculitis?
Why is it important to treat?
Supportive care
Glucocorticoids if kidney is involved to prevent damage
(Rash will heal on its own w/o scarring; steroids will not help)
A patient presents wtih these itchy lesions.
What is your next step in diagnosing the patient?
KOH exam
- If you see branched, septated hypae = tinea corporis
- Dermatophyte
33 yo obese patient reports developing recurrent painful nodules on the axilla for the past 5 years.
What do you tell her about her condition?
A. It is caused by lack of proper hygiene
B. It is a chronic condition that can affect axilla, groin, buttocks
C. The medications available can achieve long term cure
D. This condition is best treated surgically
B. It is a chronic condition that can affect axilla, groin, buttocks
- This is hidradenitis suppurativa
- Blockage of hair follicles -> painful bumps
- Not caused by lack of proper hygiene
- Smoking, excess weight and metabolic syndrome might play a role in the pathogenesis
-
Keys to diagnosis
- Recurrent painful nodules for several years
- Affects axilla, groin, buttocks
A pearly papule with rolled borders and telangiectasias that bleeds easily is most likely which kind of skin tumor?
How would you treat it?
Basal cell carcinoma
(This is nodular BCC = classic presentation)
- Unlikely to metastasize, but may be locally invasive
- Surgical excision (Mohs if on the face)
Medications that block IL-4 and IL-13 would be useful in treating which skin condition?
Atopic dermatitis
- IL-4 and IL-13 mediate the Th2 response and result in the downregulation of filaggrin
76 year old develops these tense blisters:
A. Antibodies targeting the hemidesmosome
B. Antibodies targeting the desmosomes
C. Antibodies targeting keratin 5 and Keratin 14
D. Antibodies targeting keratin 1 and 10
A. Antibodies targeting the hemidesmosome
Hemidesmosome anchors epidermis to basement membrane
Desmosome attaches epidermis cells to each other
-
Bullous pemphigoid
- Older patient
- Antibodies targeting the hemidesmosome
- Separation of the basal layer and the basement membrane
Which skin tumors are most common in patients who are immunosuppressed?
Squamous cell carcinoma
(Basal cell most common in general population)
A fungal infection living in the hair shafts and causing hair loss is most likely…
Tinia captis
What manifestations of viral rashes should prompt HIV testing?
- Widespread or giant Molluscum lesions, especially if the face is involved
- Caused by poxvirus
- Disseminated herpes zoster, large ulcerated herpes zoster
- Caused by Reactivation of varicella zoster
- Lesions suspicious of Kaposi Sarcoma
- Caused by HHV8
What percentage of melanomas arise within pre-existing nevi?
30%
The rest arise de novo
What is the most common melanoma subtype?
Association with what exposure?
What mutation?
Superficial spreading melanoma
Intermittent sun exposure
BRAF mutation
Which kind of tumor is most likely to develop from an actinic keratosis?
Squamous cell carcinoma
BUT not all SCCs are preceded by actinic keratoses
Which skin diorder is caused by overproduction of TNF-alpha, IL-17, and IL-23?
Psoriasis
Production of these cytokines driven by Th1 and Th17 helper T cells
Describe the cutaneous presentation of calciphylaxis
Violacious, reticulated patches
Bullae -> tissue necrosis -> ulceration
Very painful!
- Suspect in older patinets with kidney failure
28 year old woman develops a painful widespread rash.
What would be the most important information to gather from the patient to establish the diagnosis and etiology?
A. medication history
B. her exposure to other contacts
C. her recent travel history
D. her vaccination history
A. medication history
Toxic epidermal necrolysis
- Painful, widespread rash affecting >30% of body
- <10% = SJS
- Large sheets of desquamation; leaves behind dermis and some epidermis
- Usually triggered by adverse drug reaction
- Anticonvulsants: Carbamazepine, phenytoin
- Antibiotics: Bactrim, sulfas
Identify the basement membrane
Which patients are at particular risk of complications due to chicken pox?
- Pregnant women
- Neonates
- Immunocomproised patients
Who should receive a shingles vaccine?
People ages 60+
Even if they haven’t had chicken pox, or have already had shingles
Identify the subcutis
Describe the presentation of calcinosis cutis.
Which connective tissue diseases is it associated with?
Hard, painful nodules favoring sites of trauma
Advanced dermatomyositis (more common in juvenile)
Systemic Sclerosis (the C of CREST syndrome)
A patient is placed on an anti-TNF medication adalimumab to treat her psoriasis.
What is the most important condition to screen for in a patient who is on a TNF alpha blocker?
Latent TB infection
In which epidermal layers are keratinocytes most likely proliferating?
Basal layer
What lesion is this?
Benign or malignant?
Dermatofibroma
- Single, small, round, firm papule
- Pink to reddish brown
- Dimple sign
- Common on lower extremities
- Basically a scar; usually initiated by skin injuries (ex: insect bite)
Describe the presentation of acute cutaneous lupus erythematosus
- Classic malar rash
- Butterfly rash on cheeks, extends onto nose
- Spares nasolabial folds; sharp demarcation
- Dermatomyositis does not spare nasolabial folds
- Variable appearance: erythema, edema, telangiectasia, erosions
- Triggered by sun exposure
- Associated with anti-dsDNA antibody, systemic disease
44 year old healthcare worker reports several year hist of the following itchy rash that improves when he is away from work.
What is the mechanism of action?
Delayed (Type IV) hypersensitivity reaction
- Driven by T cell sand monocytes/macrophages
- Do patch testing to determine specific allergen
A patient complains of itchy finger webs and on examination has scaling between the fingers, a few scaly papules on the wrists, and edematous pink papules and a few nodules on the scrotum. Next step:
A. Recommend testing for STDs
B. Skin scraping for KOH to evaluate for tinea manuum
C. Skin scraping for Scabies preparation
D. Treatment for psoriasis
C. Skin scraping for Scabies preparation
“Scrotal nodules are scabies until proven otherwise”
Identify the layers of the epidermis in this image
- Basement membrane is pink, under the basal layer
- Not labeled
- Basal = single layer
- Spinous layer is thick
- Granular layer is thin, cells are flatter
- Cornified layer is thick; no nuclei - the keratinocytes are dead
28 year old otherwise healthy male develops this rash 3 weeks after URI symptoms. He reports the rash started with one large patch, then multiple small oval patches appeared few days later.
What is the best treatment?
A. Oral steroids
B. Oral tetracycline antibiotics
C. Oral macrolide antibiotics
D. Topical steroids and reassurance
D. Topical steroids and reassurance
- This is pityriasis rosea
-
Keys:
- Rash 3 weeks after URI
- Begins with a large patch
- Small oval patches appear days later
- May have “Christmas tree” pattern on back
-
Will resolve on its own
- Topical steroids if itchy/uncomfortable
- **If palms of hands and soles of feet are involved, test for secondary syphillis**
Identify the dermis
Lithium and Beta-blockers are medications that could cause flares of which skin condition?
Psoriasis
Which protein imparts tensile strength to the skin and makes up 75% of its dry weight?
Interstitial collagen
Found in the dermis
Gottron’s papules, extensor surface eczema, heliotrope rash involving eyelids and nasolabial folds, shawl sign, and calcinosis are characteristics of what autoimmune disorder?
What non-cutaneous findings might be present?
Dermatomyositis
- Proximal muscle weakness
- Dysphagia
- Malignancy
- Strong assoociation with dematomyositis in adults and malignancy; may be present at initial manifestation of disease, usually appears within a few years
- Interstitial lung disease
Describe IgA Vasculitis (Henoch-Scholein Purpura)
- “Typical Patient”:
- Arteries affected:
- Presentation:
IgA Vasculitis (Henoch-Scholein Purpura)
- “Typical Patient”: Children 3-15 y/o
- Arteries affected: Small vessels; immune complex mediated
- Presentation:
- Recent URI
- Palpable purpura
-
GI
- Colicky abdominal pain
- Vomiting, diarrhea
- Joint pain/myalgia
-
Hematuria
- “Cola-colored urine”
“Increased keratinocyte proliferation and turnover, leading to thick scaly plaques” characterizes which skin disease?
Psoriasis
A patient presents with this rash.
Physical exam reveals multiple, extensive round papules and plaqes diffusely distributed around the body. They are a little scaly.
The patient reports a recent sore throat treated with antibiotics
What is the most likely cause of this condition?
How should it be treated?
Guttate psoriasis
- May be initial presentation of psoriasis, or in patients who have had psoriasis for many years
- Multiple, extensive round papules and plaques; diffuse
- Will scaly
- Triggered by:
- Strep pharyngitis
- Beta blockers
- Lithium
- Stress
-
Treatment: widespread disease
- UV light phototherapy with narrow spectrum of UVB
- Biologics targeted against TNF-alpha, IL-23, or IL-17
What is the most important predictor of melanoma prognosis?
Breslow thickness
- Deeper tumors = worse prognosis
- Vertical spreading is more indicative than horizontal spreading
Which drugs are most likley to cause urticarial reactions?
- Pain medications
- NSAIDs
- Opiates (morphine may cause histamine release)
- ACE inhibitors (-> angioedema)
What cause pemphigus vulgaris?
Describe the presentation
Autoantibodies against the desmosome
Non-tense blisters and erosions due to separation of keratinocytes from each other (especially those in the spinous layer)
Describe the clinical presentation of HSV skin lesions
- Cluster of grouped vesicles with an erythematous base
- If the lesion is old, you will see crusted erosions
- Tingling, itching, burning on the skin before vescicles appear
-
Recurrent, painful
- Remains dormant in local nerve ganglia – this allows it to reactivate periodically (usually in the same area)
- Usually no constitutional symptoms
- May be triggered by UVB radiation or stress
18 year old has a history of a chronic itchy rash since childhood that waxes and wanes in intensity.
What drives the pathophysiology of this condition?
Impaired barrier function of the skin;
This is Atopic Dermatitis
Mutation in filaggrin -> decreased filaggrin
or
Cytokines IL-4, IL-13 -> decreased filaggrin
25 yo suddenly breaks out into this widespread rash on her trunk composed of thin oval slightly scaly patches. It initially started with one large patch. 3 weeks ago she had a slight fever and cold like symptoms
How would you treat this condition?
This is pityriasis rosea
- Oval, salmon colored thin macules or patches with a thin scale
- Mostly affects the trunk
- May have “christmas tree pattern” on the back
- Acute presentation
- May be due to reactivation of HHV 6 or 7
Treat with reassurance and topical steroids if itchy/uncomfortable
- Will self-resolve in 3-8 weeks
Describe the pathogenesis of neurofibromatosis
- Deletion of neurofibromin gene (a tumor suppressor
- -> Activation of RAS
- -> Cafe-au-lait spots, lisch nodules on the iris
Describe the presentation of dermatomyositis
- Proximal weakness
-
Dysphagia
- More common in dermatomyositis than polymyositis
- F>M
- Affects children and adults
- Childhood onset not associated with malignancy
-
Skin manifestations
- Polymyositis + skin manifestations = dermatomyositis?
- Sun-exposed erythema
- Heliotrope rash
- Involves nasolabial folds
- Eczema on extensor surface of joints
What are these flat brown spots?
Benign or malignant?
Solar Lentigines - benign
- Flat, light brown macules
- Lighter than typical nevi
- Common on sun-exposed areas
- Caused by increaed melanin (same number of melanocytes)
- No treatment necessary, but recommend sun protection
What features help to distinguish psoriatic arthritis from other arthritis?
Psortiatic arthritis is associated with:
- History of psoriasis
- Sausage digits
- Both erosive and new bone changes on x-ray
- Nail pitting
If a patient presents with sebaceous adenomas or carcinomas, what should you screen for?
Mutations in DNA mismatch repair genes
- Sebaceous adenomas are carcinomas are rare in the general population, but common in people with the Muire-Torre subset of hereditary non-polyposis colorectal cancer (Lynch syndrome)
What skin lesion is this?
Benign or malignant?
Lipoma
- Soft, ill-defined, rubbery, painless
- Subcutaneous nodule
- Much larger than a cyst
- Does not drain/discharge like a cyst
Which cells of the epidermis are important for presenting antigens to T cells and sensitizing the immune system to that antigen?
Langerhans cells
Describe the skin reaction associated with gluten sensitivity
Dermatitis herpetiformis
- Pruitic papulovesicles or excoriated papules
- Extensor surfaces, buttocks, back
- Caused by deposition of IgA in the papillary dermis
- -> Immune cascade
- Treatment = gluten avoidance, dapsone
Which germ line mutations are associated with melanoma?
CDKN2A / P16
CDK4
Bleeding gingivae, petichiae, ecchymosis, follicular hyperkeratosis and corkscrew hairs would increase your suspicion for which nutritional disease?
Scurvy
(Ascorbic acid aka Vitamin C deficiency)
Staphylococcus bacteria are implicated in many bacterial skin infections.
Which relatively common bacterial skin infection is not caused by staph?
Erysipelas - caused by Group A streptococcus
- Pain, superficial erythema, plaque-like edema
- Seems deeper than most things caused by staph?
Note - bacillus antrhacis can also cause skin lesions, but these are not common are present with a “black eschar”
Reactivation of HHV 6 or 7 may result in which skin rash?
Pityriasis Rosea
- Rash will self resolve, treat with topical corticosteroids if itchy/uncomfortable
What treatment is used to treat widespread psoriasis?
- Ultraviolet light phototherapy with narrow spectrum of UVB
- Targeted therapy (immune-modulating agents)
- TNF-alpha blockers
- IL-23 blockers
- IL-17 blockers
A patinet presents with complaints of GI upset and this skin rash.
What is the most appropriate treatment?
This is likely dermatitis herpetiformis, the skin version of celiac disease
Treatment = Avoid gluten, dapsone
- Pruritic papulovesicles or excoriated papules
- Extensor surfaces, buttocks, back
Caused by IgA deposition in the papillary dermis
Which vaccine vaccinates against HPV?
Which types?
Grdasil
HPV 6, 11, 16, 18
6, 11 = low risk of causing cancer
16, 18 = high risk of causing cancer
A 42-year-old white male presents with a “new mole” on his back, first noticed by his wife 4 months ago. It is itchy sometimes and bleeds easily.
What is this skin lesion?
Benign or malignant?
Sebhorrheic keratosis - Benign
- Superficial, raised epidermal growth
- Stuck-on quality
- Gently picking/scratching -> crumbling, flaking, lifitng off
- Do not go away
Which of the following is among the common causes of Stevens-Johnson syndrome?
a. Syphilis
b. Pneumococcal Pneumoniae
c. Cytomegalovirus
d. Phenytoin
e. Herpes simplex virus
d. Phenytoin
- Sulfa abx
- Anticonvulsants (Phenytoid, lamotrigine, carbamazepine)
- NSAIDs
- Tetracyclines
What protein is most important for wound healing?
Collagen
Which cells in the epidermis produce melanin?
Melanocytes
Which of the following is true about these nail changes associated with psoriasis?
A. She needs to get a clipping to test for onychomycosis
B. Repeated trauma caused these nail changes
C. Topical treatments will improve her nails
D. The condition may wax and wane
D. The condition may wax and wane
Nail changes can wax and wane, just like skin lesions
Which form of contact dermatitis requires sensitization to an antigen?
Which cells in the skin participate in this process?
Allergic contact dermatis requires sensitization
(Irritatnt contact dermatitis does not)
Langerhans cells in the epidermis present antigen to T cells to sensitize the immune system
List the 4 layers of the epidermis and the basic function of each layer
From deep to superficial
- Basal layer:
- Anchorage to the basement membrane via hemidesmosomes
- Proliferation (these are stem cells)
- Spinous layer
- Adhesion to each other via desmosomes
- Granular layer
- Differentiation
- Stratum corneum
- Death
Which antibody is associated with this skin rash?
Anti-dsDNA
- This is acute cutaneous lupus erythematosus
- MUST evaluate for SLE
- Acute cutaneous lupus erythematosus is associated wtih systemic diseas
Phototherapy can be useful in treating which skin conditions?
Psoriasis
Eczema
Possibly vitiligo
A patient with a history of psoriasis sees you in the office and reports a sudden worsening rash that started 3-4 weeks ago. She says it looks different than her typical psoriasis
- She should have an immediate skin biopsy to rule out another condition
- The condition she has may have been triggered by a strep pharyngitis
- The condition she has may have been triggered by excessive sun exposure
- She should have blood tests to rule out the condition in question
b. The condition she has may have been triggered by a strep pharyngitis
- This is guttate psoriasis
- May be the initial presentation, or can occur in patients who have had psoriasis for many years
- Multiple, extensive round papules and plaques; diffuse
- A little scaly
- Triggered by strep pharyngitis