Dermatology Flashcards
Give some differentials for a non-blanching rash:
Non blanching is caused by petechiae or purpura bleeding and can be checked via the glass test.
- Meningitis
- Henoch schonlein Purpura
- Acute leukaemia
- Haemolytic uraemic syndrome
- Compressional trauma to the skin
What is the management of a non-blanching rash?
If there is any doubt - treating as meningitis
What is erythema nodosum associated with?
Bacterial:
- Streptococcal infection
- Mycoplasma pneumonia
- TB
- Lymphogranuloma venereum
Viral:
- EBV
- Hep B
Chronic illness:
- Inflammatory bowel disease
- Sarcoidosis
- leukaemia
- lymphoma
Drugs:
- sulfonamides
- NSAIDs
- contraceptive pill
If urticaria continues for more than 24 hours, what should you investigate for?
urticarial vasculitis
How is SJS defined? and how is TEN defined?
<10% detachment of the skin - SJS
> 30% detachment of skin - TEN
How does SJS/ TENs usually present?
Prodromal symptoms
- fever
- cough
- headache
- 2- 3 days prior to onset of skin disease
Cutaneous lesion - erythematous macules which get larger and join together and eventually blister off.
Development of mucosal lesions
Mucosa involving the G.I, respiratory and G.U are all affected.
How should SJS/ TEN be managed?
Burns unit
Ophthalmology
ITU
**assess for secondary infection
IV immunoglobulins
IV Steroids
Anti-histamines
- nutritional support
- IV fluids/ electrolytes
- dressing
**infection control is key. a serious complications is infection on top of the burns
What may be seen on a histological slide of psoriasis?
Parakeratosis
Increased lymphocyte infiltration
Loss of granular layer
What are the different types of dermatitis?
Eczema
Contact
- allergy
- Irritant
Discoid
Seborrhoeic Dermatitis
- pityrosporum ovale
Venous dermatitis
What is acanthosis nigricans associated with?
Hyperinsulinemia states:
- DM
- PCOS
- Hypothyroidism
Gastric carcinoma
What is the treatment of pyoderma gangrenosum?
steroids
What is it called when there is an adverse reaction, leading to almost all the body becoming erythematous?
Acute erythroderma
What is it called when the epidermal cells release their attachment from one another in a pathological manner?
Acantholysis
Name an intra-dermis blistering disease:
Bullous Pemphigus
- damage to the desmosomes
How is Pemphigus vulgaris investigated and treated?
Nikolsky sign
Mucocutaneous lesions
Skin biopsy
- acantholysis
- Desmosome antibodies (immunofluorescent)
Treatment:
- IV immunoglobulins to gain control
- High dose prednisolone
- refer to dermatology
Which skin pathology cause sub-epidermal bullae?
bullous Pemphigoid
Where is the most common places for bullous pemphigoid to affect?
Abdomen
Inner forearms
Upper thighs
How is bullous pemphigoid investigated and treated?
Investigations:
* Nikolysky sign is NEGATIVE * Skin biopsies - Antibodies - Complement • APAG1 & 2 blood test - Anti-bodies against the particular antigens on hemidesmosomes
Treatment:
Remove medication causing it.
Oral steroids.
Azathioprine
Localised: - topical steroids.
Infection control
List some pre-malignant skin conditions:
Actinic Keratoses (squamous):
- erythematous silver plaques
- cryotherapy, 5 fluorouracil
Bowen’s disease (squamous):
- squamous cell carcinoma in situ
- 5 fluorouracil
Lentigo Maligna:
- macular pigmentation area
What is the treatment for rosacea?
Avoidance of triggers
- sunlight etc
1st:
- topical metronidazole
- Topical Brimonidine - vasoconstriction
- topical benzyl peroxide
2nd:
- laser treatment
What are some complications of shingles?
Herpes Zoster Ophthalmicus
- *if it involves the tip of the nose this is Hutchison’s sign and suggestive of ophthalmology involvement
- refer urgently to ophthalmology
Ramsay Hunt Syndrome
Post herpetic neuralgia
- most common in the elderly
Dissemination
- immunocompromised
What tests can be done to diagnose VZV/ Shingles?
Tzanck smear
PCR
**usually it is a clinical diagnosis though
An individual with fever, lymadnopahty, sore throat and fatigue is prescribed antibiotics. they then break out in a large erythematous rash, what is the likely pathogen?
EBV
- do not prescribe penicillin. it induces a hypersensitivity rash
What are the broad types of psoriasis?
Plaque Psoriasis
Guttate
- following a strep infection
Erythrodermic psoriasis
- medical emergancy
Koebner
- develops over a scar
Inverse
- develops over the flexures
Palmer/pustular
Psoriatic arthritis
What are the different types of basal cell carcinomas?
- Nodular
- most common
- squamous
- pigmented
- sclerortic
How is the prognosis of Melanoma measured?
Breslow’s depth
What are the different types of melanomas?
Superficial Malignant melanoma
Nodular
Subungnal
Amelanotic melanoma
Lentigo maligna melanoma
- develops form Lentigo Maligna (benign)
Acaral Melanoma
What is an immunological therapy used for melanoma?
Vemurafenib
- BRAF V600 mutation
Ipilimumab
- Anti CTLA -4
What are the surgical incisions for melanoma?
<1mm = 1cm
> 1mm = 2cm
What are some side effects of topical steroids?
thinning of skin
lightening of the skin on darker skin
What are the treatments for plaque psoriasis?
1st line:
- emollients and anti-pruritus medication
- topical steroids + vitamin D analogue
2nd line:
- double the vitamin D analogue
3rd line:
- increased topical steroid dose + coal tar
What is the most common cause of fungal nail infections?
Trichophyton Rubrum
What type of surgery can be used for squamous cell and basal cell carcinoma in cosmetically important sites?
Moh’s micrography
Which blistering skin condition typically involves the mucosa?
- what other symptom helps differentiate it?
Bullous Pemphigus
easily ruptured blisters - especially with horizontal pressure applied
- Nikolsky’s sign
What conditions are associated with Seborrheic dermatitis?
Parkinson’s
HIV
How is bullous pemphigoid investigated?
Skin biopsy with immunofluorescence IgG to the basement membrane
What are the main diagnostic features of skin cancer?
Change in shape
Change in colour
Change in size
How does actinic keratosis present?
Scaly lesions, which are not well demarcated upon sun exposed surfaces
- multiple lesions may be present
What is the treatment for actinic keratosis?
Topical fluorouracil
Topical Diclofenac
cauterage
Incision
What is the treatment for rosacea?
1st line:
Topical metronidazole
Topical Brimonidine
Topical Benzoyl perioxide
2nd line:
tacrolimus
laser therapy
What are some triggers to psoriasis?
Stress Infection - especially strep Trauma - Kobner Drugs - lithium/ NSAIDs/ Antimalarials Climate Smoking
What are the nail changes seen in psoriasis?
Nail pitting
Onycholysis
Subungual hyperkeratosis
What are the most common drugs to cause TEN?
Sulfonamides Anti-epileptics Penicillins Allopurinol NSAIDs
What is the treatment for alopecia areata?
Topical steroids
Topical Minoxidil
Phototherapy
Contact immunotherapy
What is the management for TEN?
Stop the medication causing the reaction
Admitted to ITU for burns
IV Immunoglobulin
Antihistamines
Steroids
Fluids
Analgesia
What investigations should be done into Alopecia?
Examination:
- Hair pull test
- Dermoscopy
- check eyebrows
- check occipital region
- check for scaring
Bloods
- TFT
- B12
Fungal samples
Syphilis serology
Autoimmune screen
Skin Biopsy
What skin manifestation is typically seen with pancreatic cancer?
Thrombophlebitis migrans
List come skin conditions seen with Diabetes:
Necrobiosis lipoidica
- waxy shiny yellow skin
Acanthosis nigricans
Granuloma annulare
What is Erythema Multiforme most commonly caused by?
Herpes simplex - 70%
Mycoplasma
CMV
What skin condition is seen with lung cancer?
Erythema Gyraton Repens
What skin condition is typically seen with glucagonomas?
Necrolytic migratory erythema
What investigations should be done into ulcers?
Bloods:
- FBC - anaemia
- Glucose levels
Orifices:
- urine dipstick for glucose
X-ray:
- Duplex ultrasound
- Angiography if arterial
E
S
- Skin swabs
- ABPI
What complications can occur with venous ulcers?
Bacterial colonisation
Lipodermatosclerosis
Lymphoedema
Squamous cell carcinoma
- Marjolin ulcer
How are venous ulcers managed?
Life style factors
Elevation of leg
Compressional bandages
(if ABPI >0.8)
Non- absorbent hydrocolloid gel dressings
Topical hydrocortisone for surrounding tissueWhat is
What are the two grading systems used for Malignant melanoma?
Breslow’s depth
Clark’s Staging
Where is malignant melanoma most like to spread to and what are some poor prognostic factors?
Liver
Eyes
Prognostic:
- Male
- High Miosotis
- Lymphatic spread - distant metastasis
- Ulceration
What can cause squamous cell ulcers?
Sun exposure
Long term ulceration
Long term exposure to impressiveness medication
- kidney transplant (cylosporin)
What is the treatment for Basal Carcinoma?
Moh’s
- complete circumferential removal
- Cryotherapy/ Radiotherapy
What are the triggers for psoriasis?
Stress
Streptococcal infection - Guttate
Injury - Koebner
Sunburn
Drugs
- beta blockers
- lithium
- NSAIDs
- TNF- alpha
What is an medical emergency psoriasis?
Erythrodermic psoriasis
- generalised psoriasis
What nail changes are seen in psoriasis?
Nail pitting
Onycholysis
Subungual Hyperkeratosis
Yellow brown discolouration
Damaged nail plate with loss of nail
What are the main infections that can occur in Eczema?
Eczema herpticum - Herpes simplex virus infection
Staph infection
- MRSA
- Staph Aureus
How is contact dermatitis tested for?
Patch test
How does seborrheic dermatitis present and how is it treated?
Dandruff around the:
- eyes
- eyebrows
- nasolabial folds
- Cheeks
Cradle cap in the babies
Erythroderma
- in the elderly
Miconazole + Hydrocortisone
What are the causes of erythema multiforme?
Mycoplasma HSV Drugs: SNAPP - Sulfonamides - NSAIDs - Allopurinol - Penicillin - Phenytoin
In SJS, what worrying infection is someone more at risk of?
HIV
Name some causes of pruritus:
Cholestasis
Haematological:
- Anaemia
- Polycythemia rubra vera
- Leukemia
- Hodgkin lymphoma
Endocrine:
- Hypothyroidism
- DM
- Pregnancy
Skin:
- Urticaria
- Eczema
- Dermatitis Herpetiformis
On biopsy of bullous pemphigoid what would you expect to see?
Subepidermal blistering with eosinophil rich inflammatory infiltrate
What are the clinical signs of psoriasis?
Extensors Plaque Well demarcated Auspitz sign Koebner effect
What two systemic drugs are used in psoriasis?
Methotrexate
Cyclosporine
What are the clinical findings of eczema?
Flexure surface Lichenification Scratch marks Small vesicle formation Itchy
What skin disease is associated with poor zinc absorption?
Acrodermatitis enteropathica
Classic triad of:
- peri-oral, peri- acral dermatitis
- diarrhoea
- Alopecia
Caused by:
- primary zinc transporter defect
- secondary to deficiency - seen when weaning, cystic fibrosis
What are some risk factors for acne?
Age
12- 24 years
Family history
Greasy skin
What is a serious type of acne that require steroid treatment and what are some causes?
Acne fulminans
- Anabolic steroids
- Isotretinoin A
What are some complications of acne?
Scarring
Dyspigmentation
Psychological effects
What are the treatment options for acne vulgaris, in order of 1st line:
1st line:
- topical benzoyl peroxide
- Oral contraceptive
2nd line:
- Oral antibiotics - tetracycline, erythromycin
- topical antibiotics
3rd line:
- isotretinoin A
What tests need to be done when on isotretinoin A?
Monthly LFTs and lipids
Name two creams used is psoriasis which contain both a potent steroid and vitamin D:
Dovobet
Enstilar
Name some common skin blistering conditions:
Chickenpox
herpes
impetigo
Pompholyx eczema
How is Dermatitis herpetiformis treated? and what is the risk of this medication?
Gluten free diet
Dapsone
- haemolytic anaemia
- especially true in G6PD deficiency
What are the subtypes of epidermolysis bullosa and what is their inheritance pattern?
Epidermolysis bullosa simplex
- autosomal dominant
Epidermolysis bullosa dystrophica
Junctional Epidermolysis bullosa
- autosomal recessive
Name some drugs that cause TEN:
Penicillin
Co-trimoxazole
Carbamazepine
NSAIDs
What are some of the causes of erythroderma?
Atopic eczema
Psoriasis
Drugs:
- penicillin
- allopurinol
- Sulphonamides
Cutaneous T cell lymphoma
What is a major complication of erythroderma, what is it typically seen with and how should it be managed?
Leaky capillary syndrome
Psoriasis
ITU admission
What is the general treatment of erythroderma?
Monitoring:
- fluid
- Electrolytes
- albumin
- Temperature
Fluids
Electrolytes
Warmth
Bed rest
steroids
What are the general complications of erythroderma?
High output heart failure
Hypothermia
Fluid loss
Increased metabolic rate
What is the underlying pathological process to erythema multiforme? and name some common causes:
Type IV hypersensitivity reaction
- T cell mediated
- herpes simplex
- EBV
- Anti-epileptic drugs
- Mycoplasma infection
- SLE
- HIV infection
How is erythema multiforme treated?
Most will self resolve in 2-4 weeks.
Persistent:
- aciclovir
or
- azathioprine
How is pyoderma gangrenosum treated?
High dose oral steroids
What are the symptoms of Drug induced hypersensitivity syndrome:
Typically caused by Anticonvulsant therapy
- eosinophilic reaction
occurs 2-4 weeks later
Maculopapular rash fever lymphadenopathy arthralgia pharyngitis periorbital oedema
What will a blood film show on Drug induced hypersensitivity syndrome:
Eosinophilia
Lymphocytosis
Atypical lymphocytosis
What are the features of rosacea:
Flushing of the skin around:
- cheeks
- Nose
- Forehead
Telectangasia
Pustule formation
Rhinophyma
- due to sebaceous gland enlargement
What is the Nikolsky sign?
When a blister is rubbed laterally and causes it to shed/ burst.
Differentiates between an:
- intra-epidermal blister
- Sub-epidermal blister
What are the histological findings of eczema?
Spongiosis
- fluid in the upper levels between the keratinocytes
- Thickening of the epidermis - lichenification
- Hyperkeratosis in the upper levels
What are some triggers for eczema?
Infection/ systemic and local
Detergents
Stress/ anxiety
Teething in children
Cat fur
What are some clinical features of Eczema:
Itchy erythematous scaly patches
Flexural distribution
Lichenification
Scratch marks
Small vesicle formation
- which may weep
Hyperpigmentation/ hypopigmentation
Follicular hyperkeratosis
- usually seen on the back of the arms
- association
What are the viral infections that can effect someone with eczema?
HSV - Eczema herpaticum
Molluscum contagiosum
Both require acyclovir
What are some of the severe complications of eczema?
Secondary infection
Kaposi’s varicelliform eruption
Keratoconjunctivitis
Retarded growth in children
Where are the potent and very potent steroids typically used?
On palm surfaces due to thickening of skin
What are the three age groups who get seborrhoeic eczema?
Babies
- cradle cap
Teenagers
- dandruff
Elderly
- can cause erythroderma
What are the two peak onsets of psoriasis?
Teenagers
50-60s
What gene is associated with psoriasis?
PSORS1
What are the different types of psoriasis??
Chronic plaque psoriasis
Guttate
Erythroderma
- systemic reactions
Pustular
- usually has systemic systems
Palmopustular
Inverse
What is one of the risk factors of using vitamin D preparation on extensive psoriasis?
Hypercalcemia
What advice should be given to patients on methotrexate?
Use contraception
- need to be off for 3-6 months before pregnancy
LFTs need regularly checked
Avoid alcohol
Avoid NSAIDs
How does ustekinumab work?
IL12/23 inhibitor
Which drugs are typically implicated in Bullous Pemphigoid?
NSAiDs
Furosemide
Penicillin
What ulcer develops over venous ulcers following long term irritation?
Marjolin’s ulcer
How can acne rosacea be differentiated from seborrhoeic dermatitis?
Sparing of the nasolabial folds
What gene is Psoriasis associated with?
HLA B13/17
If someone develops eczema herpcitum how shoud they be managed?
Admitted to hospital
Aciclovir
In liver failure how can you differentiate a spider naevi from another skin condition?
It will blanche and refill from the middle
What is your treatment of eczema herpaticum?
Due to HSV which spreads throughout damaged eczema skin
Stop topical steroids
Fluxocacillin
Acyclovir
