Skin Flashcards
What are the 4 layers of the Epidermis
From top to bottom: S. corneum S. granulosum S. spinosum (prickle layer) S. basaleFrom top to bottom: S. corneum S. granulosum S. spinosum (prickle layer) S. basaleFrom top to bottom: S. corneum S. granulosum S. spinosum (prickle layer) S. basaleFrom top to bottom: S. corneum S. granulosum S. spinosum (prickle layer) S. basaleFrom top to bottom: S. corneum S. granulosum S. spinosum (prickle layer) S. basaleFrom top to bottom: S. corneum S. granulosum S. spinosum (prickle layer) S. basale
Describe the S. corneum layer?
non-nucleated Contains keratinnon-nucleated Contains keratinnon-nucleated Contains keratinnon-nucleated Contains keratinnon-nucleated Contains keratinnon-nucleated Contains keratin
Describe the S. granulosum layer?
Nuclei disintegrated
Describe the S. spinosum layer?
Cells linked by desmosomes
Describe the S. basale layer?
mitosis
cells bound to BM by hemidesmosomesmitosis
cells bound to BM by hemidesmosomesmitosis
cells bound to BM by hemidesmosomesmitosis
cells bound to BM by hemidesmosomesmitosis
cells bound to BM by hemidesmosomesmitosis
cells bound to BM by hemidesmosomes
What is the name for increased S.corneum and therefore increased keratin?
Hyperkeratosis
What is the name for nuclei in S. corneum
Parakeratosis
What is the name for an increase in S. spinosum?
Acanthosis
What is the name for a decrease in cohesions between keratinocytes?
Acantholysis
What is the name for intercellular oedema?
Spongiosis
What is the name for a linear pattern of melanocyte proliferation within epidermal basal cell layer (can be reactive or neoplastic)?
Lentiginous
Define dermatitis/eczema:
Interchanagable terms for a group of disorders with the same histology
Presents with inflamed, dry, itchy rashesInterchanagable terms for a group of disorders with the same histology
Presents with inflamed, dry, itchy rashesInterchanagable terms for a group of disorders with the same histology
Presents with inflamed, dry, itchy rashesInterchanagable terms for a group of disorders with the same histology
Presents with inflamed, dry, itchy rashesInterchanagable terms for a group of disorders with the same histology
Presents with inflamed, dry, itchy rashesInterchanagable terms for a group of disorders with the same histology
Presents with inflamed, dry, itchy rashes
Where does atopic dermatitis effect infants?
Face + scalp
Where does atopic dermatitis effect older than infants?
Flexural areas
If chronic - lichenification occurs
persits into adulthood in thouse with a FHx of atopyFlexural areas
If chronic - lichenification occurs
persits into adulthood in thouse with a FHx of atopyFlexural areas
If chronic - lichenification occurs
persits into adulthood in thouse with a FHx of atopyFlexural areas
If chronic - lichenification occurs
persits into adulthood in thouse with a FHx of atopyFlexural areas
If chronic - lichenification occurs
persits into adulthood in thouse with a FHx of atopyFlexural areas
If chronic - lichenification occurs
persits into adulthood in thouse with a FHx of atopy
What hypersensitivity can cause contact dermatitis?
Type IV e.g. to nickel or rubber
What are the clinical features of contact dermatitis?
Erythema Swelling PruritisErythema Swelling PruritisErythema Swelling PruritisErythema Swelling PruritisErythema Swelling PruritisErythema Swelling Pruritis
Where does contact dermatitis commonly effect?
Ear lobes and neck (jewellery)
Wrist (leather watch straps)
Feet (shoes)Ear lobes and neck (jewellery)
Wrist (leather watch straps)
Feet (shoes)Ear lobes and neck (jewellery)
Wrist (leather watch straps)
Feet (shoes)Ear lobes and neck (jewellery)
Wrist (leather watch straps)
Feet (shoes)Ear lobes and neck (jewellery)
Wrist (leather watch straps)
Feet (shoes)
What is the histology of acute dermatitis?
Spongiosis Inflammatory infiltrate in dermis Dilated dermal capillariesSpongiosis Inflammatory infiltrate in dermis Dilated dermal capillariesSpongiosis Inflammatory infiltrate in dermis Dilated dermal capillariesSpongiosis Inflammatory infiltrate in dermis Dilated dermal capillariesSpongiosis Inflammatory infiltrate in dermis Dilated dermal capillaries
What is the histology in chronic dermatitis?
Acanthosis Crusting ScalingAcanthosis Crusting ScalingAcanthosis Crusting ScalingAcanthosis Crusting ScalingAcanthosis Crusting Scaling
What is seborrhoeic dermatitis (dandruff)?
Inflammatory reaction to yeast - Malassezia
Where does seborrhoeic dermatitis affect infants?
Cradle cap (large yellow scales on scalp)
Where does seborrhoeic dermatitis affect young adults?
Mild erythema
Fine scaling
Mildly pruritic
Affects; face, eyebrow, eyelid, anterior chest, external earMild erythema
Fine scaling
Mildly pruritic
Affects; face, eyebrow, eyelid, anterior chest, external earMild erythema
Fine scaling
Mildly pruritic
Affects; face, eyebrow, eyelid, anterior chest, external earMild erythema
Fine scaling
Mildly pruritic
Affects; face, eyebrow, eyelid, anterior chest, external earMild erythema
Fine scaling
Mildly pruritic
Affects; face, eyebrow, eyelid, anterior chest, external ear
Define psoriasis:
a skin disease marked by well-demarcated red, itchy, scaly patches.
What is Auspitz’ sign?
Rubbing of psoriasis plaques to cause pin-point bleeding
Where does psoriasis effect and what does it look like?
Salmon pink plaques with silver scale
Affecting extensor aspects of knees, elbows and scalpSalmon pink plaques with silver scale
Affecting extensor aspects of knees, elbows and scalpSalmon pink plaques with silver scale
Affecting extensor aspects of knees, elbows and scalpSalmon pink plaques with silver scale
Affecting extensor aspects of knees, elbows and scalpSalmon pink plaques with silver scale
Affecting extensor aspects of knees, elbows and scalp
What is Koebner phenomenon in psoriasis?
Lesions form at the site of trauma
Histology of psoriasis:
Parakeratosis
Loss of granular layer
Clubbing of rete ridges giving “test tubes in a rack” appearance
Munro’s microabscerssesParakeratosis
Loss of granular layer
Clubbing of rete ridges giving “test tubes in a rack” appearance
Munro’s microabscerssesParakeratosis
Loss of granular layer
Clubbing of rete ridges giving “test tubes in a rack” appearance
Munro’s microabscerssesParakeratosis
Loss of granular layer
Clubbing of rete ridges giving “test tubes in a rack” appearance
Munro’s microabscerssesParakeratosis
Loss of granular layer
Clubbing of rete ridges giving “test tubes in a rack” appearance
Munro’s microabscersses
Define Munro’s microabscesses
Munro’s microabscess is an abscess (collection of neutrophils) in the stratum corneum of the epidermis due to the infiltration of neutrophils from papillary dermis into the epidermal stratum corneum.
Less common types of psoriasis are:
Flexural psoriasis
Guttate psoriasis - raindrop plaque distribution, usually seen 2 weeks post strep throat
Erythodermic/pustular psoriasisFlexural psoriasis
Guttate psoriasis - raindrop plaque distribution, usually seen 2 weeks post strep throat
Erythodermic/pustular psoriasisFlexural psoriasis
Guttate psoriasis - raindrop plaque distribution, usually seen 2 weeks post strep throat
Erythodermic/pustular psoriasisFlexural psoriasis
Guttate psoriasis - raindrop plaque distribution, usually seen 2 weeks post strep throat
Erythodermic/pustular psoriasisFlexural psoriasis
Guttate psoriasis - raindrop plaque distribution, usually seen 2 weeks post strep throat
Erythodermic/pustular psoriasis
Psoriasis is associated with:
Arthritis (5-10%) Nail changesArthritis (5-10%) Nail changesArthritis (5-10%) Nail changesArthritis (5-10%) Nail changesArthritis (5-10%) Nail changes
What are the nail changes associated with psoraisis?
Pitting
Onycholysis
Subungal Hyperkeratosis
(POSH)Pitting
Onycholysis
Subungal Hyperkeratosis
(POSH)Pitting
Onycholysis
Subungal Hyperkeratosis
(POSH)Pitting
Onycholysis
Subungal Hyperkeratosis
(POSH)Pitting
Onycholysis
Subungal Hyperkeratosis
(POSH)
Define lichin planus
a disease of the skin and/or mucous membranes that resembles lichen.
The aetiology is unknowna disease of the skin and/or mucous membranes that resembles lichen.
The aetiology is unknowna disease of the skin and/or mucous membranes that resembles lichen.
The aetiology is unknowna disease of the skin and/or mucous membranes that resembles lichen.
The aetiology is unknowna disease of the skin and/or mucous membranes that resembles lichen.
The aetiology is unknown
What are the 5 “p’s” describing lichen planus lesions?
Pruritic Purple Polygonal Papules Plaques
They also have a mother of pearl sheenPruritic Purple Polygonal Papules Plaques
They also have a mother of pearl sheenPruritic Purple Polygonal Papules Plaques
They also have a mother of pearl sheenPruritic Purple Polygonal Papules Plaques
They also have a mother of pearl sheen
What is Wickam’s striae
A fine white network on the surface of lesions in lichen planus
Where does lichen plaus occur?
Usually on the inner surfaces of wrists
Can also affect oral mucous membranes where the lesions have a lacy appearanceUsually on the inner surfaces of wrists
Can also affect oral mucous membranes where the lesions have a lacy appearanceUsually on the inner surfaces of wrists
Can also affect oral mucous membranes where the lesions have a lacy appearanceUsually on the inner surfaces of wrists
Can also affect oral mucous membranes where the lesions have a lacy appearance
What is the histology of lichen planus
Hyperkeratosis with saw-toothing of rete ridges and bvasal cell degeneration
Define erythema multiforme
Erythema multiforme is a hypersensitivity reaction usually triggered by infections, most commonly herpes simplex virus (HSV). It presents with a skin eruption characterised by a typical target lesion. There may be mucous membrane involvement.
What and where is the classic lesion for erythema multiforme?
Annular target lesions on the hands and feet
What causes erythema multiforme?
Infections (e.g. herpes simplex, mycoplasma) Drug reactions (e.g. penicillin, salicylates, anti-malarials)Infections (e.g. herpes simplex, mycoplasma) Drug reactions (e.g. penicillin, salicylates, anti-malarials)Infections (e.g. herpes simplex, mycoplasma) Drug reactions (e.g. penicillin, salicylates, anti-malarials)Infections (e.g. herpes simplex, mycoplasma) Drug reactions (e.g. penicillin, salicylates, anti-malarials)
What can be seen on histology of erythema multiforme?
Subepidermal bullae
Define pemphigus
a skin disease in which watery blisters form on the skin.
Name 3 types of bullous disease:
Dermatitis herpetiformis Pemphigoid PemphigusDermatitis herpetiformis Pemphigoid PemphigusDermatitis herpetiformis Pemphigoid PemphigusDermatitis herpetiformis Pemphigoid Pemphigus
Define bullous disease:
any disease marked by eruptions of blisters, or bullae, filled with fluid, on the skin or mucous membranes.
Describe the pathophys of pemphigus:
IgG Abs binds to desmosomal proteins –> intraepidermal bulla
PemphiguS Bullae are SuperficialIgG Abs binds to desmosomal proteins –> intraepidermal bulla
PemphiguS Bullae are SuperficialIgG Abs binds to desmosomal proteins –> intraepidermal bulla
PemphiguS Bullae are SuperficialIgG Abs binds to desmosomal proteins –> intraepidermal bulla
PemphiguS Bullae are Superficial
What are the clinical features of pemphigus?
Bullae are easily ruptured
Found on skin AND mucosal membranesBullae are easily ruptured
Found on skin AND mucosal membranesBullae are easily ruptured
Found on skin AND mucosal membranesBullae are easily ruptured
Found on skin AND mucosal membranes
What is the histology of pemphigus?
Intraepidermal bulla
Netlike oattern of intercellular IgG deposits
AcantholysisIntraepidermal bulla
Netlike oattern of intercellular IgG deposits
AcantholysisIntraepidermal bulla
Netlike oattern of intercellular IgG deposits
AcantholysisIntraepidermal bulla
Netlike oattern of intercellular IgG deposits
Acantholysis
Define pemphigoid:
is a rare skin condition that causes large, fluid-filled blisters.
The blisters develop on areas of skin that often flex — such as the lower abdomen, upper thighs or armpits.
Bullous pemphigoid is most common in people older than age 60.is a rare skin condition that causes large, fluid-filled blisters.
The blisters develop on areas of skin that often flex — such as the lower abdomen, upper thighs or armpits.
Bullous pemphigoid is most common in people older than age 60.is a rare skin condition that causes large, fluid-filled blisters.
The blisters develop on areas of skin that often flex — such as the lower abdomen, upper thighs or armpits.
Bullous pemphigoid is most common in people older than age 60.is a rare skin condition that causes large, fluid-filled blisters.
The blisters develop on areas of skin that often flex — such as the lower abdomen, upper thighs or armpits.
Bullous pemphigoid is most common in people older than age 60.
Describe the pathophys of pemphigoid:
IgG Abs bind to hemidesmosomes of BM –> subepidermal bulla
PemphigoiD bullae are DeepIgG Abs bind to hemidesmosomes of BM –> subepidermal bulla
PemphigoiD bullae are DeepIgG Abs bind to hemidesmosomes of BM –> subepidermal bulla
PemphigoiD bullae are DeepIgG Abs bind to hemidesmosomes of BM –> subepidermal bulla
PemphigoiD bullae are Deep
What are the clinical features of pemphigoid?
Large tense bullae on erythmatous base
Often on forearms, groin and axillae
In the elderly
Bullae do not rupture as easily as pemphigusLarge tense bullae on erythmatous base
Often on forearms, groin and axillae
In the elderly
Bullae do not rupture as easily as pemphigusLarge tense bullae on erythmatous base
Often on forearms, groin and axillae
In the elderly
Bullae do not rupture as easily as pemphigus
What is the histology of pemphigoid?
Subepidermal bulla with eosinophils
Linear deposition of IgG along BMSubepidermal bulla with eosinophils
Linear deposition of IgG along BMSubepidermal bulla with eosinophils
Linear deposition of IgG along BM
Define Dermatitis herpetiformis:
a skin manifestation of celiac disease. Extremely itchy bumps or blisters appear on both sides of the body, most often on the forearms near the elbows, as well as on knees and buttocks.
Describe the pathophys of Dermatitis herpetiformis:
Associated with coeliac
IgA Abs bind to BM –> subepidermal bullaAssociated with coeliac
IgA Abs bind to BM –> subepidermal bullaAssociated with coeliac
IgA Abs bind to BM –> subepidermal bulla
What are the clinical features of Dermatitis herpetiformis?
Itchy vesicles on extensor surface of elbows and buttocks
What is the histology of Dermatitis herpetiformis?
Microabscesses which combine to form subepidermal bullae
Neutophil & igA deposits at tips of dermal papillae.Microabscesses which combine to form subepidermal bullae
Neutophil & igA deposits at tips of dermal papillae.Microabscesses which combine to form subepidermal bullae
Neutophil & igA deposits at tips of dermal papillae.
Epidermal (i.e. from keratinocytes) cutaneous neoplasms can be:
Benign Premalignant MalignantBenign Premalignant MalignantBenign Premalignant Malignant
Name 1 benign epidermal cutaneous neoplasm
Seborrhoeic keratosis
Name 3 premalignant epidermal cutaneous neoplasms
Actinic (solar/Senile) keratosis
Keratoacanthoma
Bowen’s diseaseActinic (solar/Senile) keratosis
Keratoacanthoma
Bowen’s diseaseActinic (solar/Senile) keratosis
Keratoacanthoma
Bowen’s disease
Name 2 malignant epidermal cutaneous neoplasms
Squamous cell carcinoma
Basal cell carcinomaSquamous cell carcinoma
Basal cell carcinomaSquamous cell carcinoma
Basal cell carcinoma
Define seborrhoeic keratosis:
one of the most common noncancerous skin growths in older adults. A seborrheic keratosis usually appears as a brown, black or light tan growth on the face, chest, shoulders or back. The growth has a waxy, scaly, slightly elevated appearance.
What are the clinical features of seborrhoeic keratosis:
Rough plaques Waxy Stuck on Appear in middle age/elderlyRough plaques Waxy Stuck on Appear in middle age/elderlyRough plaques Waxy Stuck on Appear in middle age/elderly
Define actinic keratosis:
is a rough, scaly patch on your skin that develops from years of exposure to the sun. It’s most commonly found on your face, lips, ears, back of your hands, forearms, scalp or neck.
Characteristics of actinic keratosis:
Rough Sandpaper like Scaly lesions on sun-exposed areasRough Sandpaper like Scaly lesions on sun-exposed areasRough Sandpaper like Scaly lesions on sun-exposed areas
Histology of actinic keratosis:
SPAIN
Solar elastosis Parakeratosis Atypia/dysplasia Inflammation Not full thicknessSPAIN
Solar elastosis Parakeratosis Atypia/dysplasia Inflammation Not full thicknessSPAIN
Solar elastosis Parakeratosis Atypia/dysplasia Inflammation Not full thickness
Define keratoacanthoma:
a low-grade skin cancer tumor that is similar to squamous cell carcinoma (SCC). It originates in the skin’s pilosebaceous glands, or hair follicles. This skin cancer tumor grows rapidly, in just a few weeks to a few months.
Characteristics of keratoacanthoma:
Rapidly growing dome shaped nodule May develop a necrotic, crusted centre Grows over 2-3 weeks Clears spontaneouslyRapidly growing dome shaped nodule May develop a necrotic, crusted centre Grows over 2-3 weeks Clears spontaneously
Histology of keratoacanthoma:
Hard to differentiate from SCC
Atypia/dysplasia throughout epidermis, nuclear crowding and spreading through BM into dermisHard to differentiate from SCC
Atypia/dysplasia throughout epidermis, nuclear crowding and spreading through BM into dermis
Define Bowen’s disease:
a very early form of skin cancer, which is easily curable. The main sign is a red, scaly patch on the skin. The abnormal growth takes place in the squamous cells – the outermost layer of skin – and Bowen’s disease is sometimes referred to as “squamous cell carcinoma in situ”.
Characteristics of Bowen’s disease:
Intra-epidermal squamous cell carcinoma in situ
Flat
Red
Scaly patches on sun-exposed areasIntra-epidermal squamous cell carcinoma in situ
Flat
Red
Scaly patches on sun-exposed areas
Histology of Bowen’s disease:
Full thickness atypia/dysplasia
BM intact - i.e. not invading the dermisFull thickness atypia/dysplasia
BM intact - i.e. not invading the dermis
Define Squamous cell carcinoma (SCC):
the uncontrolled growth of abnormal cells in the skin outer squamous cells of the epidermis. It occurs as a result of keratinization of the epidermal cells and has the potential to metastasize to other regions of the body.
Characteristics of Squamous cell carcinoma (SCC):
When Bowens has spread to involve the dermis
Similar characteristics to Bowens but may ulcerateWhen Bowens has spread to involve the dermis
Similar characteristics to Bowens but may ulcerate
Histology of Squamous cell carcinoma (SCC):
Atypia/dysplasia throughout epidermis
nuclear crowding and spreading through BM into dermisAtypia/dysplasia throughout epidermis
nuclear crowding and spreading through BM into dermis
Define Basal cell carcinoma:
Basal cell carcinoma begins in the basal cells — a type of cell within the skin that produces new skin cells as old ones die off.
Basal cell carcinoma often appears as a waxy bump, though it can take other forms. Basal cell carcinoma occurs most often on areas of the skin that are often exposed to the sun, such as your face and neck.
Most basal cell carcinomas are thought to be caused by long-term exposure to ultraviolet (UV) radiation from sunlight. Avoiding the sun and using sunscreen may help protect against basal cell carcinoma.Basal cell carcinoma begins in the basal cells — a type of cell within the skin that produces new skin cells as old ones die off.
Basal cell carcinoma often appears as a waxy bump, though it can take other forms. Basal cell carcinoma occurs most often on areas of the skin that are often exposed to the sun, such as your face and neck.
Most basal cell carcinomas are thought to be caused by long-term exposure to ultraviolet (UV) radiation from sunlight. Avoiding the sun and using sunscreen may help protect against basal cell carcinoma.
Characteristics of Basal cell carcinoma:
AKA rodent ulcer
Slow growing tumour
Rarely metastatic but locally destructive
Pearly surface, often with telangiectasiaAKA rodent ulcer
Slow growing tumour
Rarely metastatic but locally destructive
Pearly surface, often with telangiectasia
Histology of Basal cell carcinoma:
Mass of basal cells pushing down into the dermis
Palisading (nuclei align in outermost layer)Mass of basal cells pushing down into the dermis
Palisading (nuclei align in outermost layer)
Melanocytic (i.e. from melanocytes) cutaneous neoplasms can be:
Benign - melanocytic nevi (=moles).
Malignant - melanomaBenign - melanocytic nevi (=moles).
Malignant - melanoma
How can benign melanocytic nevi (moles) be classified?
Junctional Compound IntradermalJunctional Compound Intradermal
Histology of malignant melanoma is:
atypical melanocytes
Initially grow horizontally in epidermis (radial growth phrase)
Then grow vertically into dermis (vertical growth phase)
Vertical growth produces buckshot appearance (=Pagetoid cells)atypical melanocytes
Initially grow horizontally in epidermis (radial growth phrase)
Then grow vertically into dermis (vertical growth phase)
Vertical growth produces buckshot appearance (=Pagetoid cells)
What are pagetoid cells?
buckshock appearance due to vertical growth in malignant melanoma
What is the most important prognostic factor in melanoma?
Breslow thickness
Subtypes of melanoma are:
Lentigo maligna melanoma - Flat, slowly growing black lesion on sun-exposed caucasians
Superficial spreading malignant melanoma - irregular borders with variation in colour
Nodular malignant melanoma - can occur on all sites, commoner in young
Acral lentiginous melanoma - palms, soles and sublingual areas
Define: Stevens Johnson Syndrome (SJS)
a form of toxic epidermal necrolysis, is a life-threatening skin condition, in which cell death causes the epidermis to separate from the dermis. The syndrome is thought to be a hypersensitivity complex that affects the skin and the mucous membranes.
Define Toxic Epidermal Necrolysis (TEN)
a potentially life-threatening dermatologic disorder characterized by widespread erythema, necrosis, and bullous detachment of the epidermis and mucous membranes, resulting in exfoliation and possible sepsis and/or death
Name two dermatological emergencies and describe why they are dangerous:
Stevens Johnson Syndrome - sheets of skin detachment 30% of body surface area
What is Nikolsky sign?
a skin finding in which the top layers of the skin slip away from the lower layers when slightly rubbed.
In SJS and TEN this means there is prominent mucosal involvment
What can cause SJS and TEN?
Commonly drugs e.g. Sulfonamide Abx and anticonvulsants
Define Pityriasis rosea
a mild, noncontagious skin disorder common among children and young adults, and characterized by a single round spot on the body, followed later by a rash of colored spots on the body and upper arms.
What distribution does pityriasis rosea have?
Salmon pink rash appears first (=herald patch) followed by oval macules in a christmas tree distribution.
When does pityriasis rosea appear and how is it treated?
Appears after a viral illness
Remits spontaneousily
