Dermatology Flashcards
(219 cards)
1
Q
What is erythema multiforme?
A
- hypersensitivity reaction triggered by infections, most commonly HSV
- presents as a skin eruption characterised by typical target lesion
- there may be mucocutaneous involvement
- acute and self limiting, usually without complication
- typically affects young adults 20-40
- there is a genetic tendancy
2
Q
Spot diagnosis
A
Erythema multiforme
- few to hundreds of skin lesions erupt in 24 hours, usually seen first on back of hands/feet and spread to limbs and trunk
- upper limb more commonly affected than lower limb
- face, neck and trunk are common sites
- may have associated mild itch or burning sensation
- initial lesions are sharply demarcated, round macules which become raised papules and form plaques
- lesions start to blister or crust and usually evolve over 72 hours
- typical lesion = tagrt lesions with 3 concentric colour zones, dusky centre, pale pink, bright red outer ring
- lips are often swollen
- may see mucous erosions/ulcers generally on lips and cheeks and tongue
3
Q
What are the 2 most common causes of erythema multiforme?
A
- HSV 1, less commonly HSV 2
- Mycoplasma pneumonia
4
Q
Treatment of severe erythema multiforme
A
- need to treat cause r.e. antivirals or antibiotics for mycoplasma pneumonia
- could use steroids if severe 0.5-1mg/kg/day prednisolone
- if recurrent can treat with continuous aciclovir for 6 months at dose of 10mg/kg/day in divided doses
- other treatments: dapsone, antimalarial drugs, azathoprine
5
Q
Outcome for erythema multiforme
A
- usually resolves spontaneously without scarring over 2-3 weeks
- can take up to 6 weeks in major cases
- significant eye involvement in erythema multiforme major can rarely result in vision loss
6
Q
What is pityriasis alba?
A
- low grade type of ezcema/dermatitis
- generally seen in children, 3-16 years old
- pityriasis refers to the characteristic fine scale and alba to its pale colour (hypopigmentation)
Clinical presentation:
> most lesions occur on face, especially cheeks and chin
> patches vary in size from 0.5 -5cm
> usually oval, round or irregular
> hypopigment is more noticable in summer and scaling is more noticable in winter
7
Q
Evolution of pityriasis alba rash
A
- slightly scaly pink patch or plaque with palpable papular surface
- hypopigmentation with fine surface scale
- post inflammatory hypopigmentation without scale
- resolution
8
Q
Spot diagnosis
A
Pityriasis alba (fine scale with hypopigmentation)
9
Q
Treatment of pityriasis alba
A
- none if asymptomatic!
- otherwise can use moisturiser, mild topical steroid (0.5-1% hydrocortisone) to reduce itch if present
10
Q
What is an exanthem?
A
- widespread rash accompanied with systemic symptoms of fever, malaise and headache
- usually infective cause such as virus or reaction to a toxin or immune response
11
Q
Causes of exanthems
A
Varicella (chickenpox)
Measles (morbillivirus)
Rubella (rubella virus)
Roseola (herpes viraus 6B)
Erythema infectiosum (parvovirus B19)
Also include: acute HIV, IM and aminopenicillin rash, pityriasis rosea (herpes 6/7), erythema multiforme, non-specific viral exantham
Bacterial causes
- staph: toxic shock syndrome, scalded skin syndrome
- strep: scarlet fever, step toxic shock-like syndrome
12
Q
Spot diagnosis
A
Varicella (chickenpox)
13
Q
Spot diagnosis
A
Measles - caused by morbilivirus
14
Q
What is the diagnostic oral finding in measles?
A
Koplik spots
- usually manifest 2-3 days prior to measles rash
- clustered white lesions on buccal mucos (opposite the lower 1st and second molars)
“grains of salt on reddish background”
15
Q
How is chickenpox transmitted?
A
Respiratory droplet or through direct contact with fluid from open sores
16
Q
Describe the characteristic rash of chickenpox.
A
- itchy red papules which progress to vesciles
- usually on stomach, back and face then progress to other body parts
- can see the same lesions in the mouth
- may be associated with fevers, headache, cold-like symptoms, vomiting an diarrhoea
- blisteres clear up within 1-2 week weeks but can scar
17
Q
Chickenpox incubation period
A
- 10-21 days
18
Q
Diagnosis of chickenpox
A
- PCR on wound swab from vesicle
- serology IgM and IgG is most useful in pregant women
19
Q
Complication of varicella/chicken pox
A
- secondary bacterial infection of lesions
- dehydration from vomiting and diarrhoea
- exacerbation of asthma
- viral pneumonia
- shingles
More severe complications are generally seen in adults or immunocompromised children
- disseminated varicella (high morbidity)
- CNS complications: Reye syndrome, GBS, encephalitis
- thrombocytopenia and purpura
20
Q
Varicella in pregnancy
A
- in non-immune pregnant women exposure to varicella can cause viral pneumonia, premature labour and delivery and rarely maternal death
- 25% of fetuses of mothers with chickenpox become infected
- offspinge may remain asymptomatic of develop herpes zoster at a young age without previout history of primary varicella
- however they may develop congenital varicella syndrome (TORCH)
> spontaneous abortion, fetal chorioretinitis, cataracts, limb atrophy, cerebral atrophy, microcephaly, neurological disability
21
Q
When is aciclovir or varicella-zoster IG indicated?
A
Aciclovir
- consider in patients > 12
- immunocompromised patients
Varicella-zoster IG
- can be given in case of inadvertent exposure to virus in patients with no previous hx of chickenpox in pregnancy, or if immunocompromised
> must be given within first 96 hrs
22
Q
When is a patient with chickenpox contagious?
A
1-2 days before the rash develops and until all the blisters have formed scabs (this can take 5-10 days)
It takes 10-21 to develop symptoms after exposure to virus
23
Q
Varicella vaccination
A
@ 18 months
24
Q
Describe the measles transmission
A
- highly contagious
- spread by respiratory droplets
- infectious for 2 days prior to developing symptoms and for 5 days after onset of rash
- acute infection provides almost always life long immunity
25
Describe the 4 clinical stages of measles.
1. Incubation period
- ranged from 7-14 days, on average ~10 day
- usually asymptomatic
2. Prodrome
- generally 10-12 days after exposure
- fever, malaise, anorexia, conjunctivitis, cough, coryza
- 2-3 days into prodrome koplik spots appear, usually ccur 24-48 hours prior to exanthem
3. Exanthem
- flat red spots, 0.1-1cm diagmeter appear on 4th/5th day of symptoms
- non-itchy rash stated on face and behind ears, spreads over entire trunk and extremities with sparing of soles and palms within 24-36 hrs
- spots may joint together and often rash conicides with fever
- rash fades within 3-4 days
4. Recovery
- cough may persist for up to 3 weeks
26
Diagnosis of measles
- clinical diagnosis but now often need to do lab investigations as not commonly seen
- viral NPS swab for PCR
- blood: IgM and IgG
- investigation should be done within 5 days of rash onset
27
When are antibiotics indicated in measles?
- secondary bacterial infections: otitis medial, infectious diarrhoea, pneumonia, sepsis
28
Define the complications of measles?
Approximately 30% of cases will have one or more complications
- GIT: diarrhoea, mouth ulcers, appendictis, hepatitis, mesenteric adenitis, pancreatitis
- Ears: otitis media
- Resp: croup, pneumonia
- Cardio: myopericarditis
- Haem: thrombocytopenia, DIC
- Eyes: conjunctivitis, corneal ulceration
- Renal: glomerulonephritis, renal failure
- CNS: febrile seizures, encephalitis
- Pregnancy: premature labour, fetal loss, maternal death
29
What is the most severe complication of measles?
Subacute sclerosis panencephalitis
- a fatal condition, develops decades after a measles infections due to persistent of measle virus in CNS
30
Vaccination schedule for measles
MMR @ 12 months and 18 months
31
Can varicella vaccination be given to prevent primary infection?
Yes, if given within 3 -5 days of exposure primary immunisation may prevent development of disease
32
Can MMR be given in pregnancy?
NO!
If not previously immunised against measles should avoid pregnancy for 1 month after MMR vaccination
33
When is immunoglobulin indicated for measles?
- pregnant womenn
- immunocompromised patients
- infants
Ig will not prevent meales bit can reduce severity
34
What is rubella?
- viral disease characterised by rash, swollen glands, fever
- usually mild and not significant unless pregnant du eto risk fo congenital rubella syndrome
- also known as German measles
- causes by rubella virus
- spread through direct contact with nasal or throat secretions
- contagious for 7 days prior to rash and until 7 days after rash has appeared, generally most infectious while rash is erupting
- acute infection confers lifelong immunity generally
35
Signs and symptoms of rubella
- in up to 50% of cases symptoms are mild or asymptomatic
- typical incubation period 12-23 days
- common symptoms: fever, sore throatm runny nose, malaise, tender swollen glands
- Forchheimer sign: point point petechiae noted on soft palate and uvula in prodromal period
- rash begins on face and spreads to truck and extremities
- lasts for up to 5 days, may be itchy or not
- usually not as widespread as measles
- may be associated with arthralgia and arthritis
36
Congenital rubella
- infection in first trimester of pregnancy comes with a 50% chance of infant being affected (including miscarriafe, stillbirth, congenital rubella)
Features of congenital rubella:
\> sensorineural hearing loss
\> eye abnormalities: cataract, glaucoma
\> congenital heart disease: PDA
\> mental impairments
\> meningoencephalitis
\> hepatitis and jaundice
\> diabetes mellitis
\> thyroid malfunction
37
How long after MMR should females wait until trying to concieve?
3 months
38
What is roseola?
- caused by human herpes virus type 6B (HHV-6B) and maybe type 7
- characterised by high fever lasting for 3-5 days with runny nose, irritability and tiredness
- as fever settles, exanthem may appear on face and body
- also known as roseola infantum and exanthem subitum
39
What age group is roseola seen in ?
- Generally between 6 months and 3 years of age
- Most children will have had roseola by 1 (86%)
- Spread via saliva of asymptomatic family members, with a 9-10 day incubation period after exposire
40
Signs and symptoms of roseola.
- high fever, often up to 40deg for 3-5 days
- URTI symptoms: sore throat, cough, runny nose, congestion
- irritability and tiredness
- rash appears around day 3-5 as fever settles
- typically small rose-pink or raised red spots (2-5mm) that blanch
- some spots may be surrounded by lighter halo of pale skin
- mainly affects trunk and rarely spreads to involve face/neck/arms and legs
- non-itchy, painless and don't blister
- can persist for up to 2 days
41
What is the most complication of roseola?
Febrile seizures seen in 5-15% of children
Other: encephalitis, hepatitis, myocarditis but only very rarely
42
12 month old child presents with rash predominantly on trunk, 3 days of high fever with URTI symptoms preceeding. Diagnosis?
Roseola infantum
43
What causes erythema infectiosum?
Parvovirus B19
44
What are the other names for slapped check?
Erythema infectiosum = slapped cheek
Also known as fifth disease
45
How is parvovirus B19 spread?
- respiratory droplet with incubation period of 7-10 days
46
Spot diagnosis
Erythema infectiosum
Fifth disease
Slapped cheek
47
Symptoms and complications of fifth disease
Erythema infectiosum
- symptoms: mild fever, headache, rash appears few days latera with firm red cheeks which feel burning hot, this lasts for 2-4 days which is followed yb a pink rash on limbs and truck which appears lace like
Complications:
- polyarthropathy in adults
- asplastic crisis or dangerously low blood counts in pts with autoimmune/haemolytic conditions
- spontaneous abortion, IUFD, hydros fetalis
48
Slapped cheek + lacy rash = ?
Erythema infectiosum
Fifth disease
Slapped cheek
Parvo B19
49
Young male, eruption for 2 months. Associated 5kg weight loss, several episodes of diarrhoea and abdominal discomfort.
Most likely diagnosis = dermatitis herpetiformis
DDx: pmphlolyx eczema, infections (scavies, viral, bullous impetigo), erythema multiforme, bullous pemphigoid, SLE
50
What is dermatitis herpetiformis?
- results from immunological response to gut mucosa to stimulation by dietary gluten
- majority of patients with dermatitis herpetiformis have coeliac disease
- gluten causes development of IgA antibodies against gluten tissue transglutaminase which cross reactions to epidermal transglutaminase
- there is an associated link with HLA-DQ2 and 8
- patient may describe personal or family history of other autoimmune disorders (hashimoto, pernicious anaemia, T1DM)
51
How is dermatitis herpetiformis diagnosed and treated?
Diagnosis
- biopsy: take 1 sample from lesion and 1 sample for perilesional skin
- blood: anti-transglutaminase and anti-endomysial antibodies
Management
- gluten free diet
- dapsone is initial treatment of choice but need to monitor for s/e (haemolytic anaemia and methhaemoglobinaemia, must have FBC, G6PD and renal + liver function must be done prior)
- potent topical steroids can also be used
52
Description of the dermatitis herpetiformis
- pruritic, polymorphic, grouped and symmetrical lesions consisting of erythema, urticarial plaques, palpules, vesicles , blisters
- followed by erosions, abrasions and hyperpigmentation
- seen on extensor surfaces of knees/elbows, shoulders, buttocks, sacral region and scalp
53
Describe rash of pompholyx eczema
- abrupt onset of small, clear vesicles or bullae on palmes and or soles
- prodromal itching or burning sensation
- vesicles and bullae drug out and resolve without rupturing, desquamation 2-3 weeks after
54
First line treatment for pityriasis versicolour
- econazole 1% left overnight for 3 nights
- ketoconazole 2% shampoor daily for 5 days
- miconazole 2% shampoo daily for 10 days
- selenium sulfide 2.5% shampoon to skin for 7-10days
If unresponsive = PO fluconazole 400mg STAT
55
Features which increase risk of BCC recurrence
56
Management of warts
Most cutaneous warts are self limiting and resolve within 2 years. Salicylic acid has level I-A evidence of advantage over placebo. Cryotherapy with liquid nitrogen has level I-B evidence. It has not been shown to be superior over other treatments or placebo. It may however have better efficacy for plantar warts.
Surgical excision is not recommended first line due to scarring, pain and a high rate of recurrence.
57
Define timing of ROS by location
Face: 3–5 days
Scalp: 7–10 days
Arms: 7–10 days
Torso: 10–14 days
Legs: 10–14 days
Dorsum of hands or feet: 10–14 days
Palms or soles: 14–21 days
58
Typical causes of localised itchy rashes.
a) scalp
b) back
c) hands
d) genitals
e) legs
f) feet
A) Scalp: seborrhoeic dermatitis, head lice
B) Back: Grover disease
C) Hands: Pompholyx, irritant, contact dermatitis
D) Genital: candida, lichen sclerosis
E) Legs: venous eczema
F) Feet: tinea pedia
59
What are the hallmark features of scarlett fever?
Fever, malaise, sore throat, headache
Whole body rash which spares the face, feels like sandpaper
Strawberry tongue
60
Spot diagnosis
Strawberry tongue seen in scarlett fever
61
Spot diagnosis
Bullous pemphigoid
62
What is Grover's disease?
Transient acantholytic dermatosis
- itchy truncal rash characterised
- often affects males \> 50
- often starts suddenly and is more common in winter than summer
- characteristics: central back/mid chest, small red, crusted or eroded papules, intensely itchy
- can be treated with moisturiser, topical steroid a course of tetracycline or oral antifungal
63
60 year old male, itchy rash on trunk, appeared suddenly this winter. Spot diagnosis...
Transient acantholytic dermatosis
Grover's disease
64
Spot diagnoisis for diffuse, greasy scaling in infant.
Seborrhoeic dermatitis
Also known as "cradle cap"
- salmon pink patches which may flake or peel
- not especially itchy so bubs usually appear undisturbed even when the rash is generalised
65
What causes seborrhoeic dermatitis?
- pathogenesis not completely understood
- associated with proliferation of skin commensals i.e. malasezia in its yeast form (non-pathogenic)
- its metabolites cause an inflammatory reaction
- seen in infants: babies \< 3 months and usually resolves within 6-12 months
66
Spot diagnosis
Seborrheoic dermatitis
67
What are the typical features of adult seborrhoeic dermatitis?
- winter flares, improves in summer following sun exposure
- minimal itch
- combinatio nof oily and dry mid-facial skin
- ill-defined scaly patches on scalp
- blepharitis: scaly red eyelid margins
- salmon pink, thin, scaly and ill defined plaqus in skin folds on both sides of face
- petal or reing shaped flaky patches on hair line and anterior chest
- rash in armpits, under breast, in groin and genital creases
-
68
Spot diagnosis
Seborrhoeic dermatitis
- bilateral rash in skin folds
- ring or petal shapes flaky patches on hair line
69
What is the treatment for seborrhoeic dermatitis?
- keratolytics to remove scale: salicylic acid, lactic acid
- topical antifungals to reduce malassezia
- mild topical corticosteroids for 1-3 weeks to reduce inflammation of acut flare
- may require topical tacrolimus onitment if steroids are often required to reduce adverse effects
70
What is alopecia areata?
- one or more round bald patches suddenly appear
- also known as autoimmune alopecia
- 50% of cases start in childhood
- associated with thyroid disease, vitiligo and atopic eczema
- onset or recurrence often triggered by viral infection, trauma hormonal changes, stress
- characteristics: exclamation marks hairs
- spontaneous regrowth is common
71
Spot diagnosis
Pityriasis versicolor
- common yeast infection of the skin
- flaky discoloured patches appear on chest and back
- frequently affects young adults and more common in men
- more common in hot and humid climates
72
What are the clinical features of pityriasis versicolour?
- affects trunk, neck and/or arms
- patches ma be coppery brown, pale or pink
- pale patches are more common on darker skin (pityriasis versicolour alba)
- asymptomatic but sometimes mildly itchy
- caused by malassezia
73
Treatment of pityriasis veriscolour
- topical azol cream/shampoo (econazole, ketoconazole)
- selenium sulfide
- terbinafine gel
- ciclopirox cream/solution
- propylene glycose solution
- sodium thiosulphate solution
Apply nocte before bed for at least 3 days but up to 2 weeks
Can use oral antifungals if topical agents have failed
\> suggest exercise after taking medication
74
16 year old male - suddent onset itchy rash, located on trunk and extremities. Well demarcated, drop like salmon papules with plaques and fine scale. History of tonsillitis (GAS).
Guttate psoriasis
- rare form of psoriasis
- tends to be seen in \< 30 age group
- "gutta" is tear drop in latin
- preceeded by GAS infection usually 2-3 weeks before eruption
- often resolves within weeks to months without treatment
75
When should you consider referral for oral isotretinoin for acne?
- severe: cystics, nodular, very inflammatory
- is scarring
- marked negative emotional and social effect
76
What is first line recommendation for mild acne?
Topical retinoid (teratogenic)
- adapalene 0.1% for 6 weeks and review
- tretinoin 0.025% for 6 weeks
77
What is the initial treatment recommended for moderate to severe acne?
- Oral antibiotic or OCP +/- spironolactone
- doxycycline 50-100mg daily for 6 weeks
- OCP: ethinylestradiol + cyproterone
78
Common side effects of oral isotretinoin
- dry lips, dry eyes, dry mucosal lining of nose
- early acne flares
- chelitis
- sun sensitivity
- dru skin and dermatitis
- facial erythema
- nosebleeds
- lethargy, myalgia and joint stiffness
79
Causes and treatment for balanopothitis in adults
- if circumscised: psoriasis, lichen planus, lichen sclerosis, plasma cell balantitis, fixed drugs eruption, cutaneus malignancies
- if uncircumscised: usually due to candida and rarely due to strep pyogenes
80
Lichen sclerosis
- common cause of chronic genital skin disease
- females: external genitalia but spares vagina and associated with autoimmune disease
- males: confined to glans penis
Presents with well defined white, fine wrinkled plaque which is itchy and usually hyperkeratotic and ulcerated to due scratching
- need to refer to specialist to diagnose and treat
- often use very potent topical steroids
81
Candidal vulvovaginitis
- candida albicans main cause
- recurrent = more than 4 acute episodes/year
- swab to confirm species of candida
- treatment: intravaginal therapy with imidazole or nystatin
If chronic
- uncommon, ongoing itchy, dysparunia, discharge, soreness, burning, swelling, erythema and fissuring
- doesn't mean patient is immunocompromised
- repeat swab to and treat with oral azaoles (if not pregnant)
- review treatment after 3 months
82
Management of pruritis ani.
- need to break the itch-scratch cycle
- cleaning perianal area gently using cotton wool
- use soap substitute
- apply barrier/oral subsitute
- consider bulk forming laxaity
- loose fitting cotton underwear
- may need to consider topical methypred topical if ongoing
- if ongoing may need specialist referral
83
Name 7 common blistering consitions
- bullous impetigo
- insect bites
- contact dermatitis
- burns
- pompholyx
- HSV
- varicella zoster
84
How would you diagnose an autoimmune blistering skin condition?
- histology + immunofluorescence
- provide fixed sample for histology and a fresh sample
Examples: bullous pemphigoid, dermatitis herpetiformis, pemphigoid gestonitis, pemphigus)
85
Spot diagnosis
Bullous pemphigoid
86
Cause of bullous pemphigoid
- antibodies against basement memebranes
- affects older people and presents as firm blisters with erythematous base
- can be localised or widespread
- refer to specialist
- apply betamethasone dipropionate 0.05% topically while waiting for specialist review
- can also use wet dressings
87
What rash is associated with coeliac disease?
Dermatitis herpetiformis
88
WHat is the treatment for dermatitis herpetiformis?
Dapsone 50mg daily increasing cautiously to max 200mg daily if required + gluten free diet
89
Spot diagnosis...
Pemphigus vulgaris - rare autoimmune disease characterised by painful blisters and ersoions.
90
Symptoms of serious cutaneous drug reactions
Skin pain
Facial swelling
Lip or tongue swelling
Difficulty breathing
SOB, chest pain, wheezing hypotension
Headache or neck stiffness
Sore throat
91
Drugs most commonly implicated in severe cutaneous drug reactions
- allopurinol
- antiepileptics
- NSAIDs
- sulfonamides
- penicillin/cephalosporins
- antiretrovirals
92
Stevens-Johnson Syndrome (SJS)
- significant initial influenza like symptoms, widespread mucocutaneous exfoliation with or without blisteres
- onsent within weeks (up 2 months with antiepileptics)
- causes: antiepileptics, sulfonamides, allopurinol, NSAIDs, beta lactams
93
DRESS: drug rash with eosinophillia and systemic symptoms
- initial influenza like symptoms with exanthematic rash
- nonfollicular pusules, facial oedema, lymphadneopathy, peripheral eosinophilia (\>1.5) and internal organ involvement
- can occur within 1-8 weeks but occassionally up to 4 months
- causes: antiepileptics, barbiturates, lamotrigine, sulfonamides, dapsone, minocycline, azathoprine, allopurinol, strontium
94
TEN: toxic epidermal necrolysis
- significant initila influenza symptoms
- widespread mucocutaneous exfolation with or without blisteres
- within weeks
- cause: antiepileptics, sulfonamides, allopurinol, NSAIDs, beta lactams
95
Treatment for chronic cutaneous (discoid) lupus erythematosis
- betamethasone bipropionate 0.05% topically for 4-6 weeks
OR
- mometasone furoate 0.1% for 4-6 weeks
96
Morphoea
- localised scleroderma
- excessive collagen deposition
- confined to skin without systemic involvement
- presents as one or more indurated plaques, start as faint purple and fase to ivory while as plaques become smooth and shiny
- plaques are devoid of hair
- refer for expert management using potent steroids
97
Spot diagnosis = heliotrope rash with gottron papules on hands and gottron sign over dorsum of knuckles with associated muscle weakness
Dermatomyositis
98
Leukocytoclastic vasculitis
- LCV, small vessel vasculitis
- generally idiopathic
- diagnosis: biopsy, FBC, CRP, ESR, urine microscopy, e/LFT
- if uncomplicated is self limiting, sx lasting for ~3 weeks
- if complicated or widespread start oral steroids and refer
99
Chilblains
- localised inflammatory lesions caused by cold
- develop as acutely burning, red or purple swellings in toes and fingers
- generlaly heal and resolve in 1-3 weeks
- prevent by avoiding cold and stopping smoking
- can treat with strong topical steroid and amlodipine to prevent vasospasm
- GTN has ben used to prevent but evidence is lacking
100
Andorgenetic alopecia
- male pattern hair loss
- terminal hairs replaced by shorter and finer minaturised hairs
- starts as receeding hairline on both temporals and advices to baldness on scalp vertex
- may consider minoxidill or finasteride
101
Telogen effluvium
- reactive hair loss condition leading to excessive shedding
- often occurs 3 months after a trigger (childbirth, acute severe illness, major surgery, crash dieting, sudden weight loss, new drug, changing or stopping OCP)
- should resolve within 6-9 months
102
Erythrasma
- overgrown of normal commensal bacterium Corynebacterium minutissimum
- flexural rash in groin axillae and toe webs
- may resemble intertrigo or fungal infections
Rx: fusidate sodium or clarithromycin
103
Management of severe oral mucocutaneous herpes
- use oral antivirals
aciclovir 400mg 5 x a day
famciclovir 500mg BD
valaciclovir 1g BD
104
105
Spot diagnosis and management
Tinea (ringworm)
Terbinafine 1% BD for 7-14 days
106
Treatment of scabies
- permethrin 5% cream leave on for 8 hour sminium and repeat in 7 days
107
Causes of itch without rash
- skin: scabies, dry skin (xerosis)
- neuropathy: meralgia, vulvodynia,
- metabolic: CKD, cholestatsis, pregnancy, thyroid dysfunction
- drugs: statins ACEI, diuretics
- malignancy: lympoma, leukaemia, PRV, myleoma
108
What medication can you use for uraemic itch?
Gabapentin
109
Management of perioral dermatitis
- occurs in women aged 20-50
- usually papular but can be pustular
- generall affects child and lower eyelids
- leaves clear rim around lips
- if needed to treat use oral antibiotics (for antiinflammatory effect as in rosacea)
110
Management of rosacea
- soap fee cleanser
- avoid steroids
Mild: metronidazole 0.75% BD daily for 6-12 weeks
More severe: doxycycline 50-100mg daily for up to 8 weeks, but can be on 50mg daily or second daily for 6-12 months if recurrent flares
111
Treatment of rhinophyma
- tissue hypertrophy produces thickened skin on nose which may become disfiguring
- refer for surgery (i.e laser ablation or shave excision) or isotretinoin
112
Management of angio=oedema
- oedema of subcut tissues
- resolve over hours to severel days
- consider anaphylaxis
- treatment with antihistamines often fails
- use oral steroids 25-50mg for 2-3 days
113
Topical steroid preparations and strengths
114
Atopic dermatitis
- commonly develops in the first year of life
- typically affects face, cubital and popliteal fossae, wrists and ankles
- need to avoid aggravating factors and treating inflammation
- main treatment = topical corticosteroids
- use soap alternative, keep skin hydrated with emollient
115
Which steroid would you use for mild facial dermatitis?
Hydrocortisone 1% daily until skin is clear
116
What steroid would you use to treat widespread low grade dermatitis of trunk and limbs?
Triamcinolone acetonide 0.02% ointment
117
What steroid should you use for dermititis affecting fingers, wrists or ankles?
- betamethasone dipropionatye 0.05% until clear
118
How to apply a wet dressing
- take bath or shower and lightly pat dry
- apply topicaly steroid to affected skin
- cover treated skin and damp wet dressing
- wrist in towel or wear dry clothes on tyop to keep warm
- remove wet dressing after 15-60 min
- dry the skin and apply an emollient
119
Spot diagnosis
Atopic dermatitis
- most common inflammatory skin condition world wide
- generalise skin dryness and itch
120
Difference between butterfly rash in SLE and seborrhoeic dermatitis?
Nasolabial folds are spared in SLE
121
What bacterial overgrowth cases seborrhoeic dermatitis?
Malassezia
122
What is the first line management for scalp seborrhoeic dermatitis?
- betamethasone dipropionate 0.05% lotion to scaly nocte for 7 nights
OR
- methylprednisolone aceponate 0.1% lotion topically nocte for 7 nights
OR
- mometasone furoate 01% nocte for 7 nights
123
Spot diagnosis
Senorrhoeic dermatitis
124
What rash is described as oily + dry with scaly patches
Ill defined plaques often in skin folds on both sides of the same with peta or ring shapes flaky patches on anterior chest or hair line?
Seborrhoeic dermatitis
125
What is the difference between discoid dermatitis and tinea (ringworm)
Discoid dermatitis doesn't have a central clearning unlike ringworm
126
Sport diagnosis
Discoid dermatitis
127
Management of discoid dermatitis
- potent topical steroid in ointment form
- betamethasone dipropionate 0.05% for 2 weeks
- betamethasone 0.1% for 2 weeks
- mometasone fuorate 0.1% for 2 weeks
128
What dermatitis is characterised by "crazy-paving"?
Asteatotic dermatitis
- results from drying of skin
- typically on shins of elderly patients
- can be a signs of hypothyroidism or be associated with lipid lowering drugs
- aim to to rehydrate dry skin with emollients
129
Spot diagnosis
Asteatotic dermatitis
130
Spot diagnosis
Asteatotic dermatitis
131
Contact dermatitis
- features: erythema, blisters or bullae, swelling, cracking, dryness, linchenification, increased or decreased pigmentation
- will only occur in skin that is in contact with irritatnt
- treat but avoiding soap, wearing gloves, avoiding trigger and topical steroids (or oral steroids if severe)
- common occupations: cleaners, health care workers, food handler, aterers and hairdressers
132
55F - cleaner. Spot diagnosis?
Contact dermatitis most likely
133
Drugs for treating psoriasis in primary care
Tar
Corticosteroids
Calcipotriol
Or combination therapies
134
Psoriasis
- inflammatory and hyperplastic skin condition
- characterised by erythema and scale
- plaque psoriasis most common type
- generally well dermarcated and pink with silver scale
- common sites: elbows knees, sacrum, scalp
-
135
What type of psoriasis does GAS trigger?
Guttate psoriasis (gutte = tear drops)
- treat with coal tar or LPC with salicylic acid
136
Spot diagnosis
Chroinc plaque psoriasis
137
First line psoriasis management by location/type
a) scalp
b) trunk and limbs
c) palms and soles/pustular
d) nails
e) face
A) scalp: methylprednisolone aceponate 0.1% lotion for 2-6 weeks until skin clears
B) trunk: coal tar, LPC + salicylic acid, add steroid if not controlled
(methylprednisolone aceponate 0.1% cream for 2-6 weeks)
C) palms and soles/pustular: LPC 6% and salicylic acid
D) nails: calcipotriol +betamethasone dipropionate 50/500mcg/g for up to 3 months
E) face: methyprednisolone 0.1% cream for 2-6 weeks
138
Specialist management of psoriasis
- UV b phototherapy
- methotrexate
- acitretin
- ciclosporin
- biological therapies
139
Spot diagnosis
Nail psoriasis
Pitting, onycholysis, yellowing and ridging
Associated with inflammatory psoriatic arthritis
140
Acanthosis nigricans
- assoicated with insulin resistance in obesity
- can be associated with internal malignancy
- hyperpigmented and hyperkeratotic areas
- usually symmetrical in axilla, groin, neck, cubital fossa and popliteal fossa
- mulitple skin tags common
- if cause by obesity weight loss can reverse skin changes
141
What rash can recent HSV infection cause?
Erythema multiforme
- target lesions
- usually on hands and feet
142
Causes of erythema nodosum?
Infection: strep, TB, yersinia
IBD: crohn's and ulcerative colitis
drugs: sulfonamides and OCP
Malignancy: lymphoma and leukaemia
143
Treatment for erythema nodosum
- rest
- NSAIDs
- elevate legs
- if severe symptoms: prednisolone 25mg daily for 2 weeks and taper
144
Granuloma annulare
- unknown cause
- presents with annular plaque (colours ranging from skin colour to red and violet)
- often margins feel beaded
- can occur anywhere on the body
- often confused with tinea
- may persist for years but can clear spontaneously
- if interferes with function can treat with betamethasone diprosone 0.05% for 4-6 weeks
145
Spot diagnosis
Granuloma annulare
- common inflammatory skin condition with annular, smooth, discoloured palpules and plaques
- histology shows necrobiotic granulomas
146
Lichen planus
- uncommon indiopathic inflammatory condition
- can be triggered by drugs or hepatitis C
- affects skin, hair, oral and genital mucosae
- characteristic; skin eruption is itchy, violet, polygonal , flat topped papules and lacy white lines
- skin lesions take 6-9 months to resolve with post inflammatory hyperpigmentation over 3-6 months
147
Spot diagnosis
Oral lichen planus
148
Spot diagnosis
Lichen planus of the nail
149
Necrobiosis lipoidica
- rare granulomatous skin disorder
- lesions occur on the legs
- seen in diabetics
- initially start as red nonulcerating plaques and the centres become brown/yellow with obvious telenagiectasia
150
Spot diagnosis
- necrobiosis lipoidica
- seen on the shins if diabetics
151
Pityriasis rosea
- self limiting inflammatory skin condition affecting older children and young adults
- thought to be due to a viral infection (HHV 6 or 7)
- eruption starts with a herald patch which is often mistaken for tinea
- eruption occurs around 2 weeks later with scaly, oval salmon coloured macules
- confined to trunk and proximal limbs and are arranged along the skin creases
- usually resolved spontaneously within 6-8 weeks
- if severe itch can treat with betamethasone
152
What rash is thought to be due to reactivation of human herpes virus 6 or 7?
Pityriasis rosea
153
Spot diagnosis for this herald patch?
Pityriasis rosea
- may occur a few days after viral URTI
154
Polymorphic light eruption
- idiopathic photosensitivity disorder
- most common in cooler climates
- within sun exposure pruritic erythematous papules, plaques or vesicular lesions appear on exposed skin (forearms or chest)
- lesions fade without scarring over several days
- ddx: solar urticaria, SLE, photosensitive drug eruption
155
Pyoderma gangrenosum
- associated with inflammatory bowel disease, inflammatory arthritis, haematological proliferative disorders
- destructive, non-infective, inflammatory ulcer which is often painful
- starts as inflammatory papule/pustule which slowly breaks down to form enlarging ulcer
- raised purplisk edges
- perform biopsy and culture to r/o other atypical infection and vasculitis
- treatment = immunosuppression, prednisolon 25mg daily for 2 weeks and taper while awaiting specialist referral
156
Spot diagnosis in patient with ulcerative colitis?
Pyoderma gangrenosum
157
What is the most common cutaneous manifestation of sarcoidosis?
Erythema nodosum
158
Sweet syndrome
- acute febrile neutrophilic dermatosis
- painful erythematous to blue plaque appear rapidly on face/neck and limbs
- usually accompnaied by fever and neutrophil leucocytosis
- generally after URTI but can be associated with GIT infections, IBD, pregnancy, drugs, rheumatoid arthritis, sarcoidosis, malignancy
- usually responds well to systemic corticosteroids
159
Patient who is febrile and unwell presents with this rash shortly after URTI. Spot diagnosis.
Sweet syndrome
Acute febrile neutrophillia dermatosis
160
Solar keratosis
- "sunspots"
- erythematous and scaly lesion on exposed skin
- asymptomatic and often multiple
- can be atrophic, hypertrophic, pigmented or lichenoid
- risk of malignant transformation in a single lesion is low however large number of solar keratosis indicates solar damage
- first line = cryotherapy (5 seconds)
161
Cryotherapy duration
- solar keratosis = 5 seconds
- seborhhoeic keratosis = 10-15 seconds
- superficial BCCS = double freeze thaw cycle of 20 sec
162
Field therapy for multiple solar keratosis
1. fluorouracil 5% one or twice a day for 2-4 weeks on face or 3-6 weeks on arms and legs
1. imiquimod 5% nocte 3 times weekly for 3-4 weeks
1. ingenol mebutate
163
Other name for solar keratosis
Actinic keratosis
164
Solar keratosis/actinic keratosis
- considered pre-cancerous form of SCC
- often flat or thickened papule/plaque, whit or yellow with horny surface
- \> 10 solar keratosis leads to a risk of 10-15% of developing SCC
165
Dermoscopic view of actinic keratosis (non pigment on facial skin)
- "strawberry pattern"
- border well dermarcated but may merge in surrounding skin
- pink to red pseudonetwork created but straight or wavy vessels surrouding hair follicles
- skin coloured or white circles around a yellowish clod
- surface scale
166
Dermoscopic actinic keratosis on nonfacial skin
- irregular shape
- surface scale
- erythema and sometimes with dotted vessles
- rosettes
- short shiny streaks
167
Seborrhoeic keratosis
- well defined, benign warty lesions that are often pigmented
- start to appear around 30-40 but numbers increase with age
- clinically flat lesions are difficult to distinguish form lentigo maligna
- often itchy and do not need treatment!
168
Spot diagnosis. Cancerous or benign?
BENIGN
Seborrhoeic keratosis
169
Spot diagnosis
Seborrhoeic keratosis
170
Lentigo simplex
- brown to black macule M 5mm diameter
- can occurs anywhere but less common on mucosa
- do not need treatment!
- can be difficult to distinguish from melanoma
171
Melanocytic naevi
- also known as moles
- benign localised proliferation so of melanocytes
- generally develop in children
- begin as macules, but can become raised commonly with gradual loss of pigmnet
- having many naevi is a risk factor for melanoma
- however most melanomas arise "de novo" so prophylactic removal of benign naevi is not recommended
172
Classification of melanocytic naevi
Junctional naevus: groups or nests at the junction of epidermis and dermis --\> flat mole
Dermal naevus: naevis cell nests in dermus, papule/plaque or nodule
Compound naevus: nests at epidermal-dermal jdunction, central raised area surrounded by flat patch
Combined naevus: two distinct types of mole withion same lesion, usually compound + blue naevus
173
Dermatoscopic patterns of melanocytic naevi
- reticular: lattic of intersecting brown lines
- globular: aggregated brown oval structures
- blue: steel blue uniform, structureless
- starburst: radial lines around periphery
- acral: on palms and soles, made up of parallel lines
174
Dysplastic naevi
- lesions are benign and typically larger, flat and raised compondent, irregular "smudgy" borders, vary in colour
- generally occur on trunk
- can become malignant but generally don't
- if excising for concerns take with a 2mm border
175
Basal cell carcinoma
- slow growing, invasive epithelial tumours
- arise from basal layer of epidermis
- most common form of skin cancer
- 50% of BCCS occur on head anc neck with 30% on upper trunk and the rest on limbs
- metastasis are rare but if untreated can cause extensive local destruction
176
Clinical types of BCC (4)
- pearly papule (nodular BCC)
- erythematous sclary patch or plaque (superficial BCC)
- crusted or haemorrhagic ulcer (ulcerative BCC)
- infiltrating scar like plaque (morphoeic BCC)
177
First line and alternative therapy for BCC
- surgical excision with 3-4mm margin but wider if large BCC or micronodular or morphoeic
- alternatively could use cryotherapy for primary lesions (double freeze thaw cycle for 20sec) OR topical imiquod 5% at night 5 x a week for 6 weeks
178
What margin generally should be given to a BCC excision?
3-4 mm
179
180
Risk factors for BCC
- age and sex: elderly males
- previous BCC or skin cancer
- sun damage
- repeated prior episodes of sun burn
- fair skin, blue eyes, blond or red hair
- previous cutaneous injury, thermal burn
- inherited syndromes
- radiation, immunosuppresion
181
Main physical characteristics of BCCs
- locally invasive skin tumour
- slowly growing plaque or nodule
- skin colours, pink or pigmented
- spontaneous bleeding or ulceration
182
Nodular BCC
- most common type of BCC
- shiny or pearly nodules with a smooth surface
- may have central depression or ulceration, edges appear rolled
- blood vessels cross surface
183
Spot diagnosis
Nodular BCC
- raised, pearly with rolled edge and central ulceration
184
Superficial BCC
- most common in younger adults
- slightly scaly appearance with irregular plaque
- thin transluenct rolled border
- multiple micro-erosions
185
Spot diagnosis
Superficial BCC
- slight rolled border
- multiple micro-erosions, slight scale with irregular border
186
Morphoeic BCC
- usually found in mid-facial sites
- waxy, scar like plaque with indistinct borders
- wide and deep subclinical extension
- may infiltrate cutaneous nerves (perineural spread)
- also knowns of sclerosing BCC
187
What type of BCC is this?
Morphoeic
- scar like
- waxy appearance
- indistinct borders
188
Basosquamous carcinoma
Mixed BCC and SCC
189
Squamous cell carcinoma
- second most common skin cancer in Australia
- tender, indurated lesions which appear suddently and grow rapidly
- generally on exposed skin
- 5% of SCCs metastasised and risk of spread greater for lesions (9%) on external ear or lip (14%)
- treatment of choice is surgical excision with 3-5mm margin
- review patients with a primary SCC every 6 months for at least 2 years after excision
190
Bowen disease
- SCC in situ
- well dermarcated, slowly expanding, erytematous and scaling plaque
- can ulcerate but usually asymptomatic
- 3-8% risk of invasion
- confirm diagnosis by punch or shave
- should refer to expert
- if initiating therapy can use fluouracil 5% daily for 3-4 weeks or imiquimod 5% at night for 5 days a week for 6 weeks
191
Keratocanthoma
- benign squamoproliferative lesion which can appear suddently and grow rapidly at same sites as SCC
- often presents over weeksn to a few months as an enlarging nodule with central keratotic core
- treat with surgical excision
192
From which cells does SCC arise from?
Epidermal keratinocytes
193
Risk factors for SCC
- age and sex: elderly males
- previous SCC or other forms of skin cancer
- actinic keratosis/solar keratosis
- outdoor occupation or recreation
- smoking
- blue eyes, fair skin, blond or red hair
- previous cutaneous injury
- inherited syndromes
- immunosuppression, radiation
194
Clinical features of SCC
- grow over weeks to months
- may ulcerate
- tender or painful
- located on sun-exposed sites, particularly face/lips/ears/hands/forearms and lower legs
195
Spot diagnosis
Squamous cell carcinoma
196
Spot diagnosis
Keratocanthoma
197
Margins for SCC excision
etg 3-5mm
dermnet 3-10mm
198
Risk factors for melanoma
- risk factors: multiple melanocytic naemia, family history, blistering sunburns as childhood, history of previous melanoma or non melanoma skin cancer, fair complexion and tendancy to burn, marked solar skin damage, immunodeficieny
199
Melanoma warning signs (6)
1. new or changing lesions
2. prominent and pigmented, stands out from other moles "ugly duckling"
3. rapidly growin nodule of any colour
4. of particular concern to patient
5. typical dermatoscopically features (asymmetric pigment, blue white veil, multiple brown dots, pseudopods, radial streaming)
6. changes on subsequent dermaoscopy
200
ABCDE rule of melanoma
A: asymmetry, one half different from the other
B: border irregularity
C: colour varies within lesion
D: greater than 6mm
E: evolution or changing
201
Types of melanoma
- superficial spreading is most common type (presents as irregularly pigmented macule or papule)
- nodular: aggressive and invasive, can grow rapidly and ulcerate, may defy ABCDE rule but fits EFG (elevated, firm and growing)
- acral: most common in patients with dark skin, presents on palms, soles or nail beds
- lentigo maligna: in situ melanoma, irregular brown to black facial macule
- desmplastic: rare and aggressive, scar like appearance and nonpigmented
202
Initial management of suspected melanoma?
Excisional biopsy with 2mm margins
203
When should a wide local excision be performed for a diagnosed melanoma?
Within 4 weeks
204
Follow up after melanoma?
- full skin and lymph node check every 3 months for 2 years and then every 6 months for 2 years and every year after that
Note immediate family memebers have a four fold increased risk of melanoma and should have annual skin check
205
Recommended wide local excision margins for melanoma
- in situ = 5mm
- \<1mm = 10mm
- 1-4 mm= 10-20mm
- \> than 4mm = 20mm
206
What is your spot diagnosis and management?
Superficial spreading melanoma
- excisional biopsy with 2mm margins
- A: asymmetrical
- B: irregular
- C: irregular
- D: \> 6mm
- E: unsure
207
Spot diagnosis
Acral melanoma
208
What is the Clark level of invasion for melanoma?
Level 1 = in situ melanoma
Level 2 = invasion of papilllary dermis
Level 3 = filled papillary dermis
Level 4 = invasion of reticular dermis
Level 5 = invasion of subcutaneous tissue
209
Melanoma staging
Stage 0 = in situ
Stage 1 = thin melanoma \<2mm
Stage 2 = thick melanoma \> 2mm or \> 1mm with ulceration
Stage 3 = melanoma with spread to local LN
Stage 4 = distant metastasis
210
What is the breslow thickness?
- reported for invasive melanomas
- measured verticuallr in mm from top of the granular layer to deepest point of tumour involvement
- the thicker then breslow the greater the risk of metastasis
211
Prognosis of melanoma
- in situ is cured by excision because it has no potential to spread
- risk of spread and death is mainly determined by Breslow thickness
- mets are rare if \< 0.75mm
- risk of mets if 0.75-1mm is around 5%
- \>4mm thickness = 40% risk of metastasis
212
What are the contraindications to effudex (5% fluoruacil)
Pregnancy
Dihydropyrimidine dehydrogenase (DPD) enzyme deficiency
213
214
Stevens-Johnson Syndrome
- lesser version of toxic epidermal necrosis
- hypersensitivity disorder
- blisters and erosions cover 3-10% of body
- usually starts with non specific viral URTI with a 1-14 day prodrome of fever, sore throat, diarrhoea, headache and fatigue
- develops mucosal membrane lesions (i.e. mouth ulcers)
- rash resembles target which is pathognomonic
215
What feature is pathognomonic for stevens johnson syndrome
- target lesions! with URTI prodrome
216
Common causes of SJS
SJS = NASA
NSAIDs
Allopurinol
Sulfonamides
Anticonvulsants
217
Cause of acne in teens
GENETICS
218
WHich drugs can worsen psoriasis?
Beta blockers
NSAIDs
Lithium
Anti-malarials
219
After primary melanoma excision when is a sentinel LN biopsy indicated and when should it be performed?
- indicated for all melanomas \>1mm thickeness (or if over 0.75mm if concerning features)
- should be referred for sentinel LN biopsy and WLE at the same time
