General Disease Flashcards
What is acne vulgaris + where does it usually affect?
Inflammation of the pilosebaceous unit
Face, back and chest
Explain the disease pathway of acne vulgaris.
Increased androgens causes increased sebum which blocks pores
Rupture causes inflammation
Increased propionibacterium furthers inflammation
Give examples of primary (non) + secondary (inflammatory) acne lesions?
Primary = open comedones/ blackheads and closed comedones/ whiteheads Secondary = pustules, papules and cysts
Treatment for mild non-inflammatory + inflammatory acne vulgaris?
Topical retinoid or salicylic acid
Topical retinoid + topical abx + benzoyl peroxide
Treatment for moderate + severe inflammatory acne vulgaris?
Topical retinoid + oral abx + benzoyl peroxide
Oral retinoid +/- steroids
What is acne rosacea + who is it more common in + 2 histological signs?
Inflammatory facial rash
Middle-aged women
Demodex mites and perifollicular granulomas
5 clinical features of acne rosacea?
NO COMEDONES Erythema Telangiectasia Rhinophyma Eye involvement
4 factors which irritate acne rosacea?
Alcohol
Temperature change
Steroids
Spicy foods
Suspected pathology behind acne rosacea + target treatment?
Excess Demodex mites
Ivermectin
2 optional treatment for mild + treatment for severe acne rosacea?
Topical metronidazole or oral tetracycline
Isotretinoin if severe
What is the atopic triad?
Asthma
Atopic dermatitis
Hay fever/ allergic rhinitis
Explain the disease pathway of atopic dermatitis.
Mutation in filaggrin + decreased AMP from keratinocytes causes reduced skin barrier and moisture loss
Which 3 CD4+ cells drive inflammation in atopic dermatitis?
Th2, Th17 and Th22
What is the clinical presentation + 1 histological sign of atopic dermatitis + who is it seen more in?
Poorly bordered, red, itchy and flaky rash
Spongiosis
Kids
Which sites does atopic dermatitis present in infants and children/adults?
Infants = face + extensor Children/adults = flexural
Chronic atopic dermatitis (lichen simplex) presents as what 3 things?
Lichenification
Excoration
Plaques
2 infections following atopic dermatitis + organism + presentation + treatment?
Dermatitis herpeticum, HSV, monomorphic punched-out lesions, aciclovir
Impetigo, usually staph. aureus, golden crust and ooze, fluclox
Diagnosis of atopic dermatitis?
Itch + 3 from: Rash History of atopy Dry skin Onset < age 2
Topical treatment of atopic dermatitis + adjunct therapy if not responding?
Topical steroid
Calcineurin inhibitor
2 treatments for atopic dermatitis unresponsive to previous tretment?
Phototherapy
Immunosuppresants
What is contact irritant vs allergic dermatitis? Name 3 triggers of each.
Non-immune response to trauma = soap, perfume, nappies
Type IV reaction to allergen = nickel, latex, ivy
What test is used to differenciate between irritant/allergic dermatitis + procedure + result?
Patch test
Apply allergens to back, remove after 48 hours and check after 72
Allergic = +ve
Treatment for contact allergic or irritant dermatitis?
Avoidance
Emollients
Topical steroids
Key feature which differenciates discoid eczema from psoriasis?
Eczema = intense itch Psoriasis = more pain than itch
Increased hydrostatic pressure causes what 3 things in stasis dermatitis?
Oedema
RBC extravasation
Haemosiderin deposits
5 features of stasis dermatitis?
Inflammation Hyperpigmentation Varicose veins Ulcers Lipodermatosclerosis
Treatment for stasis dermatitis?
Compression stocking + topical steroid
Which 2 places does seborrhoeic dermatitis usually present?
Nose and hairline
Topical treatments for seborrhoeic dermatitis + adjunct therapy for widespread disease?
Topical steroid
Topical antifungal
Treatment for pompholyx or acute exudative eczema?
Potassium permanganate
What is erythroderma (erythrodermic psoriasis) + 2 main causes?
> 90% of the skin turning red and flaky
Drugs and other skin conditions
Is keratinocyte AMP increased/decreased in eczema vs psoriasis?
Eczema = decreased Psoriasis = increased
What 4 things are lost in erythroderma + what are the 3 components of treatment?
Heat Mositure Protein Electrolyte Stop drug (if cause) + IV fluids + emollients
What is psoriasis vulgaris + what 4 areas does it usually affect?
Autoimmune disease causing reversible plaques and inflammation
Extensor areas, back, scalp and nails
Name 4 triggers + 3 drugs that can cause psoriasis vulgaris?
Smoking Alcohol Stress Infection Lithium, amiodarone and beta-blockers
In psoriasis, pDC produce IFN alpha which causes a Th.. and Th.. response with IL-… and IL-…? IL-… causes increased …, … and …?
Th1 and Th17
IL-17 and IL-23
IL-17
Keratinocyte proliferation, AMP and neutrophilic killing
Name the 4 key histological features of psoriasis vulgairs.
Acanthosis
Hyperkeratosis
Parakeratosis
Elongated rete ridges
Name 4 conditions associated with psoriasis vulgaris.
Psoriatic arthritis (15%)
CVD
Metabolic disease
Obesity
3 nail signs in psoriasis vulgaris?
Pitting
Subungual hyperkeratosis
Onycholysis
What is the Koebner phenomenon + Auspitz sign?
Koebner = psoriasis in area of skin trauma Auspitz = skin bleeds when scratching plaque
General treatment for psoriasis vulgaris?
Topical steroid + topical vit D analogue
2 treatments for resistant psoriasis vulgaris?
Phototherapy
Immunosuppression
3 treatments for scalp psoriasis?
Greasy ointment
Coal tar shampoo
Vitamin D analogue
Treatment for axillary psoriasis?
Calcineurin inhibitor
How does guttate psorasis present + treatment?
Red spots in young people after strep throat infection
Phototherapy
Treatment for pustular psoriasis?
Oral retinoid + PUVA
Percentage of children who suffer from an allergy?
30%
5 clinical features of anaphylaxis?
Pruritus Urticaria Wheeze Angioedema Anaphylaxis
Test + treatment for anaphylaxis?
Serum mast cell tryptase
Adrenaline 500 micrograms
Test pathway for non-anaphylactic allergic reaction?
IgE RAST bloods + skin prick
Challenge test if skin prick -ve
Skin prick and challenge testing carry risk of anaphylaxis. True or False?
True
Treatment of non-anaphylactic allergic reaction + preventative measure?
Anti-histamine
Epi-pen (300 adults and 150 kids)
What is a chronic leg ulcer?
Open ulcer that stays unhealed for at least 4 weeks
Most common type of leg ulcer (60-80%)?
Venous
4 clinical features of leg ulcers?
Pain
Exudate
Inflammation
Smell
Appearance + location + cause of an arterial ulcer?
Punched out
Lateral leg, ankle + heel
PVD
Appearance + location + cause of a venous ulcer?
Superficial wound
Medial and lateral malleoli
Reduced blood flow to the heart
Treatment of non-infected arterial vs venous ulcers?
Analgesics + non-adherent dressing
Analgesics + non-adherent dressing + 4-layer compression bandage
Life-long treatment of venous ulcers + which class is best tolerated?
Emollient Compression stockings (class 2)
4 methods of de-sloughing?
Honey
Hydrogel
Surgical debridement
Maggots
3 tests for leg ulcers?
ABPI
Swab (if infected)
Duplex scan
3 ABPI values + meaning?
<0.8 = vascular disease
0.9-1.3 = borderline/normal
> 1.5 = calcification
Name drugs which commonly cause drug eruptions + what commonly predisposes a drug eruption.
Antibiotics Antifungals Antimicrobials Anticonvulsants NSAIDs Paracetamol Phenytoin Phenobarbital Chemotherapy agents Allopurinol Azathioprine Thiazide diuretics Predisposed by viral infection
2 most common types of drug eruption + type of hypersensitivity reaction?
Exanthematous (type IV)
Urticarial (type I)
What is SJS/TEN + classic pre-skin symptoms + cause in kids vs. adults + key clinical sign?
Acute skin failure
Flu-like symptoms
Kids = viral infection (SJS) vs Adults = drugs (TEN)
Nikolskys sign +ve
Which 2 things make SJS and TEN different from erythema multiforme?
Mucosal involvement
Necrosis
Erythema multiforme clinical sign + 3 causes (+ main cause)?
Target lesions
HSV (main), Mycoplasma and drugs
What is Epidermolysis Bullosa (EB) + 3 types and what molecule + layer the mutation affects?
AD mutation in DEJ
EB simplex = keratin = epidermis
Junctional = hemidesmosome = DEJ
Dystrophic = type VII collagen = dermis
Patient with EB are at high risk of SCC. True or False?
True
What does pemphigus vulgaris (PV) cause + antibody?
Autoimmune intraepidermal blisters
Anti-desmoglein III IgG
2 main histological signs of PV + what type of bulla form + pos/negative Nikolsky’s?
Acantholysis + epidermal IgG
Thin
+ve
2 other ways PV can present?
Erosions
Mucosal blistering
Tests + treatment triad for PV?
Biopsy + immunofluorescence
Steroids + immunosuppresants + abx
What does bullous pemphigoid (BP) cause + who is it seen in + antibody?
Autoimmune subepidermal blisters + plaques
Elderly people
Anti-hemidesmosome IgG
What is the main histological sign of BP + what type of bulla form + pos/neg Nikolsky’s sign?
Basement membrane IgG
Thick
-ve
Test + treatment triad for BP?
Biopsy + immunofluorescence
Steroids + immunosuppressants + tetracycline
Is PV or BP more fatal if left untreated?
PV
What does dermatitis herpetiformis cause + linked disease + haplotype?
Subepidermal blistering
Coeliac disease
HLA DQ2
What is the dermatitis herpetiformis antibody + key histological sign?
Anti-gliadin IgA
Papillary dermal micro abscesses
What are porphyrins + what causes a porphyria?
Building blocks of haem
Lack of an enzyme which breaks down porphyrins
What is the most common porphyria + who does it affect + deficiency?
Porphyria cutanea tarda (PCT)
Older males
Uroporphyrinogen III decarboxylase
Name 3 signs + unusual sign + 3 causes of PCT.
Hyperpigmentation Hypertrichosis (excess hair) Blistering Red urine Alcoholism, viral Hep and haemochromatosis
Name 2 tests + drug for PCT?
Woods lamp
Plasma fluorescence scanning
Chloroquine (anti-malarial)
How does erythropoietic protoporphyria (EPP) present + who does it affect + deficiency?
Acute attacks of blistering, itch and erythema
Children
Ferrochelatase
Name 2 tests for EPP + key value.
Plasma fluorescence scanning = 624nm peak
RBC porphyrins
What is the management + prophylaxis for EPP?
6 monthly LFTs + RBC porphyrins
TL-01 UBV phototherapy/antioxidants/iron avoidance
How does acute intermittent porphyria present + deficiency + treatment?
Acute attack with GI/cardio/resp symptoms
PGB deaminase
Hematin + heme arginate
Name a lichenoid eruption + how it presents + key oral sign + treatment.
Lichen planus
Itchy, shiny, purple papules on wrists/shins
Wickham’s striae
Steroids
Name 4 histological signs of lichen planus.
Acanthosis
Hypergranulosis
Dermal lymphocytes
Basal cytoid bodies
What is tuberous sclerosis + genes and proteins affected + presenting triad + treatment?
AD disease causing benign tumours
TSC1 or TSC2 - tuberin and hamartin
Tumours, ash leaf macules and seizures
mTOR inhibitors
What is NF1 + protein affected and what is controls + how does it present + treatment.
AD or de novo disease affecting skin, eyes and CNS
NF1 and switches off cell cycle
Cafe au lait spots, axillary freckling, optic gliomas, tumours and Lisch nodules
MEK inhibitor
Give an example of a high penetrance Mendelian disorder.
Tuberose sclerosis
