Dermatology Flashcards
Give some causes of pyoderma gangrenosum?
Inflammatory bowel disease Acute leukaemia Polycythemia rubra vera Autoimmune hepatitis Wegeners granulomatosis Myeloma
For how long should children with impetigo stay off school for?
Stay off until had 48h of effective treatment
What is necrobiosis lipoidica?
Shiny area on shin with yellowish skin and telangiectasia seen in diabetes mellitus
What does pyoderma gangrenosum look like?
Recurring nodulo pustular ulcers with tender red/blue overhanging necrotic edge, healing with cribriform scars
What is the difference between bullous pemphigoid and pemphigus vulgaris?
Bullous pemphigoid: tense bullae filled with clear fluid on normal or erythematous skin. Blistering occurs subepidermally
Pemphigus vulgaris: thin walled and fragile blisters, few intact blisters occurring at dermal epidermal junction
What is Kawasaki disease?
Mucocutaneous lymph node syndrome
Fleeting erythematous rash associated with fever, cracked lips, red tongue, swollen hands and swollen neck glands
What is necrobiosis lipoidica diabeticorum?
Painless rash with central lipid like core surrounded by brownish purplish periphery
Found in type 1 and 2 diabetes
How do you treat necrobiosis lipoidica diabeticorum?
PUVA and improved therapeutic control
What is Kawasaki disease? How does it present?
Acute vasculitis of medium sized vessels classically involves the coronary arteries
Prolonged fever for more than 5 days with mucocutaneous changes and lymphadenopathy
Desquamation of fingers and toes begins in periungual region, may involves palms and soles and is observed 1-2 weeks after fever
How does measles present?
Generalised macular rash starting on head and spreads to trunk and extremities over few days
Rash lasts at least 3 days and fades in order of appearance
Can leave behind a brownish discolouration and can become confluent over the buttocks
A 26 year old man presents with weight loss, generalised pruritus particularly over his bottom. On examination there are some vesicles and urticarial papules over his bottom. What is it?
Dermatitis herpetiformis - systemic manifestation of coeliac
A 30 year old female who is 28 weeks pregnant presents with hyperpigmentation around cheeks, eyes and forehead giving a mask like appearance. What is it?
Melasma - mask of pregnancy
With what infections is erythema nodosum associated?
TB, sarcoid and mycoplasma
A 64 year old male presents with multiple discrete lesions of approximately 0.5-1cm in diameter over his scalp, neck and back of hands. They are scaly and rough surfaced. What are they?
Actinic keratosis
A 40 year old man presents with pruritic flat topped papules around his wrist. He has a history of bipolar disorder and takes lithium. On examination there are widespread white lace like streaky lesions on the papules and on the buccal mucosa. What is it?
Lichen planus
What drugs can cause lichen planus?
Lithium Gold Quinine Beta blockers Spironolactone
What is the correct name given to white lace like patterns found in lichen planus?
Wickhams striae
A 3 year old girl presents with macular confluent rash which appeared initially behind the ears and has spread. Over past 5 days she has had low grade fever, catarrh and conjunctivitis. Her mother is vague about her imms hx. What does she have?
Measles
What type of organism causes measles?
RNA paramyxovirus
How is measles spread?
Respiratory droplets
What is the incubation period for measles?
10-21 days
What symptoms occur in the prodromal phase of measles?
Fever Conjunctivitis Runny nose Coughing Last 5 days
What are koplik spots?
Bright red lesions with central white dot which appear on buccal mucosa in measles
How is a diagnosis of measles made?
Clinical features
Viral culture from lesions
Greater than 4x rise in antibody titres
What is subacute sclerosing panencephalitis?
Progressive brain disorder related to measles
Abnormal immune response leading to brain inflammation several years after measles infection
What are some complications of measles?
Otitis media
Pneumonia
Meningitis
Subacute sclerosing panencephalitis
A 2 year old boy is mildly unwell. His mother noticed vesicles in his mouth, palms and soles of his feet. What does he have and what is the causative organism?
Hand foot and mouth
Coxsackie A16 virus
What are characteristic features of hand foot and mouth disease?
Fever
Sore throat
Ulcerating vesicles in palms, oropharynx and soles
What is the incubation period for hand foot and mouth?
5-7 days
How do hand foot and mouth lesions heal?
Without crusting
How is chicken pox spread?
Respiratory droplets and contact with somebody who has shingles
What is the causative organism in chickenpox?
Varicella zoster virus
What are some complications of chickenpox?
Pneumonia
Encephalitis
Bacterial infection of skin
What is the incubation period for chickenpox?
14-21 days
What symptoms might be experienced in the prodromal phase of chickenpox?
Malaise
What are the 3 stages of a chickenpox rash?
Spots: red raised spots on face or chest before spreading to rest of body
Blisters: over next few hours or following day, very itchy fluid filled blisters develop on top of the spots
Scabs and crusts: after a further few days, blisters dry out and scab over to form crust which gradually fall off by themselves over next week or 2
When is chickenpox contagious until?
Until all blisters have scabbed over
Usually 5 or 6 days after rash appears
In which patients with chickenpox might you use antiviral therapy?
Systemic disease in immunocompromised
What is the first and second line treatment for scabies?
Permethrin
Malathion
What is alopecia areata?
Autoimmune condition causing discrete areas of hair loss
What is treatment for alopecia areata?
Cortisone injections into affected area
Topical cortisone creams
What are cavernous haemangiomas?
Well circumscribed and lobulated lesions which appear in first 2 weeks of life on face neck or trunk
Blood vessel malformation - benign tumour
What are symptoms of varicella pneumonia?
Tachypnoea Cough Dyspnoea Fever Cyanosis Pleuritic chest pain Haemoptysis
What are naevus flammeus?
Capillary malformation
Usually present at birth
Mainly in region supplied by cranial nerve 5
Port wine stain
If you have a well child with a cough and cold with small petechiae in the distribution of the SVC (right arm, head, neck and trunk above diaphragm). What do they have?
Cough petechiae
Vigorous coughing/vomiting raise SVC pressure sufficiently to cause capillary bleeding
What is onychogryphosis?
Over proliferation of the germinal matrix leading to excessive growth of the nail plate
How do you treat onychogryphosis?
Zadeks procedure - avulsion of nail and ablation of nail bed
Where do you find pyogenic granulomas?
Hands and face of children and young adults
Lips and gums of pregnant women
What is a pyogenic granuloma?
Benign capillary haemangiomas
How do you treat a pyogenic granuloma?
Curettage and diathermy of the base
What two features of an excised melanoma can give prognostic information about the chance of cure?
Breslow thickness
Clark level
What are predisposing factors for squamous cell carcinoma (SCC)?
Sun exposure
Radiation exposure
Pre malignant conditions: bowens, senile keratosis, lupus vulgaris, Paget’s disease
Inherited: xeroderma pigmentosum, albinism
Chronic irritation: marjolins ulcer, leukoplakia, varicose veins, osteomyelitis sinus
Infection: HPV 5 and 8
What is the histopathologic pattern in papular urticaria?
Mild subepidermal oedema
Extravasation of erythrocytes
Interstitial eosinophils
Exocytosis of lymphocytes
What bug causes scarlet fever?
Streptococcal group A infection
What bug causes cellulitis?
Streptococcus pyogenes
Sometimes staph aureus
What are multiple or genital molluscum associated with?
HIV infection
How is molluscum contagiosum transmitted?
Direct skin to skin contact
What causes hidradenitis suppurativa?
Occlusion of the ducts of apocrine glands by antigen antibody complexes leading to secondary infection and abscess formation
Which bug causes cutaneous anthrax?
Bacillus anthracis
What are risk factors for cutaneous anthrax?
Contact with infected hoofed animals - sheep goats
What is the treatment for cutaneous anthrax?
Ciprofloxacin
Doxycycline
Penicillin
What is the Eron classification for cellulitis?
Class 1: no signs of systemic toxicity and no uncontrolled comorbidities
Class 2: systemically unwell or has a comorbidity which may complicate or delay resolution
Class 3: significant systemic upset - confusion, tachycardia/pnoea, hypotension, unstable comorbidities or limb threatening infection due to vascular compromise
Class 4: sepsis or severe life threatening infection - necrotising fasciitis
What does NICE guidance say on using the Eron classification for managing cellulitis?
Admit for IV antibiotics: Eron class III or IV Severe or rapidly deteriorating Under 1 year of age or frail Immunocompromised Significant lymphoedema Facial cellulitis or periorbital
How is severe cellulitis managed?
IV benzylpenicillin and flucloxacillin
How are fungal nail infections treated?
Dermatophyte infection: oral terbinafine 6 weeks to 3 months
Candida: topical antifungals - amorolfine if mild. Oral itraconazole if severe for 12 weeks
What are differential diagnosis for shin lesions?
Erythema nodosum
Pretibial myxoedema
Pyoderma gangrenosum
Necrobiosis lipodica diabeticorum
What is the management for impetigo?
Limited localised disease: topical fusidic acid. Topical mupirocin if MRSA
Extensive disease: oral flucloxacillin or erythromycin if allergy
What are skin manifestations of SLE?
Photosensitive butterfly rash
Discoid lupus
Alopecia
Livedo reticularis
What are causes of acanthosis nigricans?
GI cancer DM Obesity PCOS Acromegaly Cushings disease Hypothyroidism Familial Prader willi Oral contraceptive pill Nicotinic acid
What is the management for acne rosacea?
Topical metronidazole if mild Oxytetracycline if severe Recommend daily high factor sunscreen Camouflage creams Laser therapy if prominent telangiectasia
What is the management for chronic plaque psoriasis?
Regular emollients
First line: for potent corticosteroid once daily plus vitamin D analogue once daily applied separately for 4 weeks
Second line: if no improvement after 8 weeks then vit D analogue twice daily
Third line: if no improvement after 8-12 weeks then potent steroid twice daily or coal tar once or twice daily
How do vitamin D analogues work for psoriasis?
Reduce cell division and differentiation to reduce scale and thickness of plaques
Avoid in pregnancy
What is hutchinsons sign?
Melanonychia
Pigmentation of proximal nail fold
Sign of subungal melanoma
What is pityriasis versicolor?
Overgrowth of Malassezia yeast
Common in young males
Multiple patches of skin discolouration mainly on the trunk
Can be flaky and itchy
Often present after spending time in sunny humid environments
How is pityriasis versicolor treated?
Topical antifungals - ketoconazole shampoo
Oral itraconazole if no response
What are predisposing factors for black hairy tongue?
Poor oral hygiene Antibiotics Head and neck radiation HIV IV drug use
What causes black hairy tongue?
Defective desquamation of the filiform papillae
What are causes of erythema multiforme?
Herpes simplex Orf Idiopathic Mycoplasma Streptococcus Drugs: penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, COCP, nevirapine SLE Sarcoidosis Malignancy
Which scoring system is used to assess severity of psoriasis?
PASI and DLQI
What is necrobiosis lipoidica diabeticorum?
Shiny painless areas of yellow/red skin on shin of diabetics often associated with telangiectasia
What is keratoderma blennorrhagica?
Skin lesions on palms or soles seen as a feature of reactive arthritis
What factors may exacerbate psoriasis?
Trauma
Alcohol
Drugs: beta blockers, lithium, antimalarials, NSAIDs, ace inhibitors, infliximab
Withdrawal of systemic steroids
What are causes of Stevens Johnson syndrome?
Idiopathic Bacteria: mycoplasma, streptococcus Virus: herpes simplex, orf Drugs: penicillin, sulphonamides, lamotrigine, carbamazepine, allopurinol, NSAIDs, oral contraceptive pill SLE Sarcoidosis Malignancy
What are causes of livedo reticularis?
Malignancy
Vasculitis
SLE
Cholesterol embolisation
What is erythema marginatum?
Pink rings on trunk and inner surfaces of arms and legs which come and go for months
Associated with rheumatic fever
What is the management of impetigo?
Topical fusidic acid
Topical retapamulin second line
MRSA: topical mupirocin
Extensive disease: oral fluclox/ erythromycin if allergy
What is the management of acne vulgaris?
Single topical therapy: retinoids, benzyl peroxide
Topical combination therapy: antibiotic, benzyl peroxide, retinoid
Oral antibiotics: oxytetracyline, doxycycline
Oral isotretinoin
What is the most significant complication of PUVA therapy for psoriasis?
Squamous cell skin cancer
How do vitamin D analogues work for psoriasis?
Reduce cell division and differentiation
What are features of lichen planus?
Itchy, papular rash on palms, soles, genitalia, flexor surface of arms
Polygonal shape, lace like - wickhams striae
Koebner phenomenon
Oral involvement in 50%
Thinning of nail plate, longitudinal ridging
Which drugs can cause lichenoid eruptions?
Gold
Quinine
Thiazides
What is the management of lichen planus?
Topical steroids
If extensive - oral steroids or immunosuppression
What is erythema nodosum?
Panniculitis characterised by tender nodules on extensor surfaces of lower legs
With which condition is erythema marginatum associated?
Rheumatic fever (part of duckett jones criteria)
Which medications can precipitate psoriasis?
Beta blockers NSAIDs Antimalarials Lithium Tapering doses of steroids
What is the most common cause of acanthosis nigricans?
Insulin resistance - increased circulating levels, spillover into skin, leads to abnormal increase in growth
What clinical features are associated with dermatomyositis?
Heliotrope rash Proximal myopathy Clubbing Lymphadenopathy RA Raynauds Calcinosis Cachexia Dilated capillary loops of base of nails Gottrons patches
What is the name of the facial rash associated with dermatomyositis?
Heliotrope rash
In what percent of dermatomyositis cases is there an underlying malignancy?
15%
What are management options for hyperhydrosis?
Topical aluminium chloride
Iontophoresis
Botox
Surgery: endoscopic transthoracic sympathetomy
What is the first line management for lichen sclerosis?
Strong topical steroid: clobetasol proprionate
What is necrobiosis lipoidica diabeticorum?
Painless rash with central yellowish lipid like core surrounded by brownish purplish periphery
Found in type 1 and 2 diabetes
What are complications of chicken pox?
Secondary bacterial infection Pneumonia Encephalitis Disseminated haemorrhagic chicken pox Arthritis Nephritis Pancreatitis
How is seborrhoeic dermatitis managed?
Topical antifungals: ketoconazole
Topical steroids
What are management options of actinic keratosis?
Prevention of further risk: sun avoidance, sun cream Fluorouracil cream Topical diclofenac Topical imiquimod Cryotherapy Curettage and cautery
What is the name of the rash seen in secondary syphilis?
Keratoderma blennorrhagica
What is the management of dermatitis herpetiformis?
Gluten free diet
Dapsone
What is the management for pyoderma gangrenosum?
Oral steroids
Immunosuppressant therapy: ciclosporin and infliximab in difficult cases
What is auspitz sign?
scratch and gentle removal of scales causes capillary bleeding in psoriasis
What is the management of psoriasis?
General measures: Avoid precipitating factors, Regular emollients to reduce scale
Topical therapies: Vitamin D analogues, Topical steroids, Coal tar preparations, Dithranol, Topical retinoids
Oral therapies: Methotrexate, Retinoids, Ciclosporin
Biological Agents eg infliximab
Phototherapy
UVB or psoralen + UVA
What are causes of acne vulgaris?
Hormonal (androgen)
Increased sebum production
Abnormal follicular keratinization
Bacterial colonisation (Propionibacterium acnes)
What are the different presentations of acne vulgaris?
Non-inflammatory - open and closed comedones
Inflammatory - papules, pustules, nodules and cysts
What is the management of acne vulgaris?
Topical therapies eg benzoyl peroxide, antibiotics, retinoids
Oral therapies eg antibiotics, anti-androgens, retinoids
Need to continue for at least 6 weeks to see effect
What are complications of acne vulgaris?
Post-inflammatory hyperpigmentation
Scarring
Psychological and social effects
What is treatment of seborrhoeic dermatitis?
Cleanse with non-soap cleanser or anti-dandruff shampoo
Keratolytic cleansers or creams containing salicylic acid and/or sulphur
Topical antifungal cream especially ketoconazole or ciclopirox
Intermittent use of mild topical steroid or tar preparations
What drugs cause SJS?
Sulfonamides: cotrimoxizole Beta-lactam: penicillins, cephalosporins Anti-convulsants: lamotrigine, carbamazepine, phenytoin, phenobarbitone Allopurinol Paracetamol NSAIDs (oxicam type mainly) Nevirapine (non-nucleoside reverse-transcriptase inhibitor)
What are non drug causes of SJS?
Viral: herpes simplex, Epstein-Barr, enteroviruses, HIV, Coxsackievirus, influenza, hepatitis,
Bacterial: Group A beta-haemolytic streptococcus, mycobacteria, Mycoplasma pneumoniae
Fungal: coccidioidomycosis, dermatophytosis and histoplasmosis
Protozoal: malaria and trichomoniasis
Immunisation: measles, hepatitis B
What is the management of actinic keratosis?
Cryotherapy
Curettage
Topical treatment: Diclofenac gel twice daily for 3 months, it is fairly well tolerated but less effective than rest. 5-Fluorouracil, cytotoxic agent. Cream applied once or twice daily for 2 to 8 weeks (efudix).
Sometimes combined with salicylic acid (actikerall). Ingenol mebutate gel (protein kinase gel) is effective after only 2–3 applications
What is management of bowens disease?
Observation in v elderly
Curettage
Cryotherapy
5-flouracil cream topical
What are treatment options for lichen simplex?
Potent topical steroids 4-6 weeks with occlusion for a few hours after application Intralesional injection steroids Coal tar Moisturiser Antihistamine
What is the management of molluscum contagiosum?
Leave alone Cryotherapy Molludab (Potsssium Hydroxide) Curettage Salicylic acid
What are underlying systemic causes of pyoderma gangrenosum?
Inflammatory Bowel Disease– more frequent in UC
Rheumatoid arthritis
Chronic Active hepatitis
Haematological malignancies
An 11 year old girl presents with increasing numbers of erythematous papules on her cheeks. There is no response to topical benzoyl peroxide gel or oral tetracycline. What are these skin lesions called? With which condition are they associated?
Facial angiofibromas or adenoma sebaceum
Associated with tuberous sclerosis
What are cutaneous associations of tuberous sclerosis?
Facial angiofibromas
Ungual fibroma
Ash leaf macules
Shagreen patch
What are treatment options for discoid eczema?
Emollients
Topical steroid
Antibiotics – topical or oral
Phototherapy
What factors can precipitate discoid eczema?
Localised injury such as scratch, insect bite or thermal burn Impetigo or wound infection Contact dermatitis Dry skin Varicose veins (varicose eczema)
Who gets discoid eczema?
Discoid eczema can affect children and adults
Slightly more prevalent in adult males than females
Males over the age of 50 years, association with chronic alcoholism
Discoid eczema can occur in atopic eczema
How should eczema herpeticum be managed?
Oral aciclovir
What causes erythema ab igne?
Chronic exposure to infrared radiation
How long does pityriasis rosea usually persist for?
8-12 weeks
Does pityriasis rosea need any management?
No
What are causes of erythema nodosum?
Idiopathic in 1/3
Infective: Streptococcal infections (often URTI), Tuberculosis, atypical mycobacterial infection
Sarcoidosis
Pregnancy
Oral contraceptive pill
Medications: penicillin, sulphonamides, hepatitis B vaccine, isotretinoin, SSRI
Rheumatological and autoimmune conditions
Inflammatory bowel disease - ulcerative colitis or Crohn’s disease
Malignancy, mainly haematological
How does rosacea present?
Flushing
Papules
Pustules
Dry and flaky facial skin
Give 3 systemic conditions which can cause pruritis
Malignancy: Lymphoma (especially Hodgkin’s), Leukaemia, Lung, Gastric tumours Chronic renal failure (dialysis) Liver Disease (intrahepatic cholestasis) Iron-deficiency anaemia Thyroid disorders: Graves Disease Infections: HIV, Hep C
What advice would you give a patient about keeping an eye on moles for melanoma?
Asymmetry in shape and / or colour
Border. Look around edge of mole. Melanoma irregular, uneven or notched border
Colour. Several different colours or shades of colour, or a single colour that is different to other moles
Dimensions (changing dimensions / size). Melanoma can spread outwards as a flat lesion, or it can grow upwards as a hard lump
UV protection advice
What can cause urticaria?
Acute viral infection: upper respiratory infection, viral hepatitis, infectious mononucleosis, mycoplasma
Acute bacterial infection: dental abscess, sinusitis
Food allergy (IgE mediated): usually milk, egg, peanut, shellfish
Drug allergy (IgE mediated): often an antibiotic
Drug pseudoallergy: aspirin, nonselective nonsteroidal anti-inflammatory drugs, opiates, radiocontrast media, these cause urticaria without immune activation
Vaccination
Bee or wasp stings
What is seborrhoeic dermatitis?
Inflammatory reaction related to proliferation of normal skin inhabitant fungus - malassezia furfur
With which conditions is seborrhoeic dermatitis associated?
HIV
Parkinson’s disease
What is the management of seborrhoeic dermatitis?
Scalp disease: OTC containing zinc pyrithione (head and shoulders), tar (neutrogena, T gel) first line. Ketoconazole second line. Selenium sulphide, topical corticosteroid
Face and body: topical antifungal ketoconazole, topical steroids
What causes pityriasis versicolor?
Malassezia furfur
What are features of pityriasis versicolor?
Commonly on trunk
Hypopigmented, pink, brown patches maybe more noticeable following suntan
Scale
Mild pruritis
What are predisposing factors for pityriasis versicolor?
Immunosuppression
Malnutrition
Cushing’s
What is vitiligo?
Autoimmune condition resulting in loss of melanocytes and consequent depigmentation of skin
Which conditions are associated with vitiligo?
Type 1 diabetes Mellitus Addison's disease Autoimmune thyroid disorders Pernicious anaemia Alopecia areata
What is management of vitiligo?
Sun block for affected areas Camouflage makeup Topical corticosteroids Topical tacrolimus Phototherapy
What is lupus pernio a manifestation of?
Sarcoidosis
What is recommended first line for chronic plaque psoriasis?
Regular emollients
Potent corticosteroid once daily plus vitamin D analogue applied separately once daily for up to 4 weeks
What are grades of pressure sore?
1: non blanching erththema over intact skin
2: partial thickness skin loss
3: full thickness, extending to subcutaneous fat
4: extensive destruction, muscle bone or supporting tissue involved
What are disk factors for pressure sore development?
Elderly CV disease Obesity Poor nutrition Immobility Smoking Neuro impairment Faecal/urinary incontinence
What are appropriate management steps for pressure sores?
Nutrition Antibiotics if infection Regular dressings Debridement Pain relief Patient positioning Tissue viability referral Pressure relieving mattress/chair
What are differentials for a white lesion in a woman’s anogenital region?
Lichen sclerosus Localised scleroderma Vitiligo SCC Bowen’s disease Lichen planus VIN
What are symptoms of lichen sclerosus?
Itching
Visible white atrophic area
Dysparunia
Constipation
What is management of lichen sclerosus?
Topical steroids
Topical emollients
Lubricants
What are complications of lichen sclerosus?
SCC Constipation Dysparunia Vulvodynia Uropathy Scarring
