Pre-Block Formative Flashcards
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What is a pyogenic granuloma?
An exaggerated healing response
A history of a lesion arising at the site of injury suggests what?
A pyogenic granuloma
What is a myxoid cyst?
A digitial myxoid cyst (sometimes called a mucous cyst) is a non-cancerous swelling that occurs on the fingers or sometimes toes.
The cyst is often connected to the lining of the finger or toenail joint, and is usually located between the joint and the nail.
What is this lesion?
Myxoid cyst
What is this lesion?
Myxoid cyst
What is a strawberry naevus?
The infantile superficial haemangioma is commonly known as a strawberry naevus (capillary haemangioma).
Clinically, they appear as red, relatively soft, and somewhat irregular in outline.
This lesion was on a sun-exposed site of an older person. What is the diagnosis?
Amelanotic melanoma
(melanoma where the malignant cells have little or no pigment)
What is a melanocytic naevus?
a.k.a a mole
A common, benign skin lesion due to a local proliferation of melanocytes.
Can get congenital or aquired melanocytic naevi.
What are the pathological classifications of melanocytic naevi?
Pathological classification of melanocytic naevi relates to where naevus cells are found in the skin.
- Junctional naevus
- Dermal naevus
- Compound naevus
- Combined naevus
Describe a junctional naevus
A flat mole.
- groups of naevus cells at the junction of the epidermis and the dermis
Describe a dermal naevus
A papule, plaque or nodule with a pedunculated, papillomatous or smooth surface.
- groups of naevus cells in the dermis
Describe a compound naevus
A central raised area surrounded by a flat patch
- groups of naevus cells at the epidermal-dermal junction as well as within the dermis
Describe a combined naevus
Usually a blue naevus and a compound naevus.
- Has two distinct types of mole within the same lesion
List some histological features of plaque psoriasis
- epidermal thickening
- absence of granular layer
- presence of parakeratosis
- Munro microabscesses
What is pityriasis rosea?
Pityriasis rosea is a viral rash which lasts aprox. 6-12 weeks.
Characterised by a herald patch followed by similar, smaller oval red patches that are located mainly on the chest and back.
Who gets pityriasis rosea?
Most often affects teenagers and young adults but can affect males and females of any age
How long does pityriasis rosea last?
Clears up in about 6-12 weeks
Pale marks or brown discolouration may persist for a few months in darker-skinned people.
How should pityriasis rosea be managed?
Treatment is with emollients and milt to moderate potency topical steroids if required but it will likely resolves in 6-12 weeks
What is isotretinoin?
Sold under the brand name: Accutane or Roaccutane
Used in treatment of severe acne
What are some important side-effects of oral isotretinoin? (Roaccutane)
- Dry skin
- Photosensitivity
- Altered lipids
- Teratogenicity (most important)
List some of the different presentations of psoriasis
- Chronic plaque psoriasis (most common)
- Flexural
- Palmoplantar
- Guttate
- Unstable plaque psoriasis (Koebner phenomeno seen)
- Scalp
- Sebopsoriasis
- Nail
- Erythrodermic
What are ash leaf macules associated with?
Tuberous sclerosis
What features are used in diagnosis neurofibromatosis?
- Axillary freckling
- Lisch nodules
- Multiple cafe au lait macules
- Sphenoid bone dysplasia
What type of hypersensitivity reaction is tested for with IgE tests and prick testing?
Type I
What are the clinical features of necrobiosis lipoidica diabeticoru?
Occurs in diabetics.
- occur in both shins (rarely found in other sites)
- symptomatic/tender
- shiny, pale, thinned with telangiectasia
- can ulcerate (ulcers at risk of bacterial infection and delayed healing)
What is Auspitz sign?
when adherent psoriatic scales are scraped or picked off pinpoint bleeding occurs
What is the Koebnar phenomenon?
describes the appearance of new skin lesions of a pre-existing dermatosis on areas of cuteanous injury in otherwise healthy skin
(psoriasis, vitiligo and lichen planus)
What is telogen effluvium?
Telogen effluvium is due to altered hair cycle and mass shedding
Is a common transient problem after childbirth
A 63 year old man presents to Dermatology as an urgen referral with a new and changing pigmented lesion on his chest, which you suspect to be a melanoma. What is the most appropriate initial mangement?
The lesion should initially be excised with 2mm margins. Further treatment and size of wider excision depends on initial pathology report.
A 60 year old lady with recurrent episodes of rash on the lower legs for 1-2 years. She is overweight with type 2 diabetes, hypothyroidism and hypertension and has recently started a new anti-hypertensive. The rash is itchy and never clears completely.
What are your differential diagnoses for red rash on legs?
What diagnosis best fits this presentation? How would you manage it?
Gravitational/stasis eczema
Prescribe topical agents and fit for compression stockings
Other differenitals to rule out for red rash on legs:
- Cellulitis (bilateral cellulitis is very unusual, and tender rather than itchy)
- Tinea corporis (tends to be unilateral)
- Erythema nodosum (manifests as more discrete tender subcutaneous swellings)
- Vasculitis (purpuric lesions rather than confluent erythema)
What is erythema nodosum?
Erythema nodosum is a type of panniculitis, an inflammatory disorder affecting subcutaenous fat.
How does erythema nodosum present?
Tender red nodules bilaterally on anterior shins.
(less commonly can affect thighs and forearms)
Accompanied by fever and joint pain.
What is pompholyx eczema?
Eczema characterised by an itchy vesicular eruption of the hands, fingers and soles of the feet.
It can be acute, recurrent or chronic.
What is the treatment for scabies?
Permethrin cream
A 26 year old man presents with a recurrent rash as shown, which tends to follow episodes of herpes simplex labialis.
What is the most likely diagnosis?
a) Eczema herpeticum
b) Bullous pemphigoid
c) Erythema multiforme
d) Bullous impetigo
e) Erythema nodosum
c) Erythema multiforme
Targetoid lesions in association with herpes simplex is consistent with a diagnosis of erythema multiforme, which can be bullous
List some risk factors for developing melanoma
- Systemic immunosuppression
- Personal history of melanoma
- Blistering sunburns in childhood
- Giant congenital naevus
- Skin type 1
A 28 year old female attends her GP following a holiday to Portugal. After a few days away, she developed an itchy spotty rash which is just starting to settle now after being home for 4 days. She’s otherwise well, with no associated systemic symptoms. She’s going away agan later in the year and is worried the same might happen again.
What is her most likely diagnosis?
Polymorphic light eruption
- Fairly common in females of this age
- Often helped with desensitisation phototherapy
Describe the Fitzpatrick skin types in re. to tanning ability
Type I: Always burns, does not easily tan
Type II: Burns easily, tans poorly
Type III: Tans after initial burn
Type IV: Burns minimally, tans easily
Type V: Rarely burns, tans darkly easily
Type VI: Never burns, always tans darkly
A 17 year old man with a history of asthma and atopic eczema attended the out of hours GPP as he developed a rash on face which has now extended down to his torso and arms. On examination, you see multiple monomorphic ersosions, however, the patient states that the rash began as small blisters. You notes a small cold sore on his bottom lip. He has a temperature of 38 degrees, feels generally unwell and has flu-like symptoms.
What is the most likely diagnosis?
Diffuse herpes simplex infection (eczema herpecticum) is a recognised complication of atopic eczema and requires emergency management
