Derm - Miscellaneous Flashcards
Erythroderma
Erythroderma - inflammatory condition when more than 95% of the skin is involved in a rash of any kind.
Causes: eczema, psoriasis, drugs e.g. gold, lymphomas, leukaemias, idiopathic
Many pts can be well in themselves, but can deteriorate and need hospital admission
Acute cases: oedema, electrolyte disturbance, feel cold, shivering. If pt is frail or has many co-morbidities it can lead to shock
Urticaria
- weals = oedematous dermal* swellings
- itchy
- it comes and goes in a few days, but in some pts new weals replace old ones so can last for long
- urticaria is not necessarily allergic
- Treatment: non-sedating antihistamines (e.g. cetirizine, loratidine)
*leads to swelling WITHOUT scaling (epidermal would be scaly)
Maculopapular rash - children vs adults
- children
usually viral infection - adults
usually drug eruption
Top 5 Drugs that cause drug eruptions?
- sulphonamides, trimethoprim
- anticonvulsants
- penicillins
- allopurinol
- NSAIDs
Stevens-Johnson Syndrome
- prodrome of fever and respiratory symptoms
- 2 or more mucosal sites and blistering*
- may be severe eye and oral involvement, with epidermal death, haemorrhagic crusting
- non-specific or targetoid eruption
- prolonged course
- affected mucosal sites and blistering are warning signs of drug eruption
Most common drugs: carbamazepine, lamotrigine, allopurinol, sulfonamide, phenobarbital.
Toxic Epidermal Necrolysis
- on the same spectrum as SJS but TEN is more severe
- fever, tachycardia, pain
- blistering and skin loss, scalded appearance
- > 30% of body surface area
- positive Nikolsky’s sign: the epidermis separates from the skin with mild lateral pressure
- causes: NSAIDs, Abs, anticonvulsants
Mx
- stop causative drugs
- supportive - analgesia, NG tube feeding
- some units use intravenous immunoglobulin
Vasculitis - DDx
- Cutaneous only (still check all bloods to exclude renal, hepatic, inflammatory, infective causes)
- Connective tissue disease
- SLE
- Rheumatoid
- Granulomatosis with polyangitis (Wegner’s) - Infection
- meningococcal septicaemia
- Post-streptococcal
- Hepatitis C - Drugs
Diabetes - cutaneous manifestations
- Necrobiosis lipoidica - affect the shin of insulin-dependent diabetics, although it may occur in non-diabetic subjects as well. Causes yellow/orange dicoloration, atrophic plaques (can visualise the blood vessels underneath), can lead to ulceration
- Tinea pedis (infections flashcards)
- Acanthosis nigricans*
- Neuropathic foot ulcer**
- Granuloma annulare: smooth discoloured plaques. They are usually thickened and ring-shaped or annular in shape. They might look like ringworm but they are not scaly therefore you can exclude fungal infection
- also a feature of obesity, PCOS, gastric malignancy
- can also happen in alcoholics, B12 deficient etc.
Adrenal disease - cutaneous manifestations
- Cushing’s –> striae, obesity
2. Addison’s –> Pigmentation of palmar crease and oral mucosa
Gastro/hepatolgy - cutaneous manifestations
- Dermatitis herpetiformis: A/w coeliac’s - extremely itchy eruption, blisters symmetrically on extensor areas. (it resembles herpes but not a viral infection)
- Hereditary Haemorrhagic Telangectasia: vascular lesions on nose, tongue and lips and can extend to gut (can present with GI bleeding or spontaneous epistaxis) due to AVM
- Spider naevi and palmar erythema*: sign of chronic liver disease
* can also be caused by thyrotoxicosis, pregnancy, etc.
Erythema Nodosum
Red (very) tender lumps on the shins, inflammation in the fat (penniculitis) so no scaling
Associations: IBD, sarcoidosis, Bhecet’s, Infection (strep, TB), pregnancy, drugs (sulphonamides, OCP)
Pyoderma Gangrenosum
Inflammatory neutorphilic condition
Affect mostly legs (but not exclusively) - postule or nodule that rapidly expands, then breaks down and ulcerates - purple or greyish border, often multifocal and very painful.
Associations: IBD, myelodysplasia, myeloproliferative disorders, rheumatoid disease, diabetes
Treatment: oral steroids, or sometimes tetracyclines
Dermatomyositis
- skin and muscle involvement (if there is no skin involvement, they call it myositis or polymyositis) - mainly proximal muscle weakness + muscle pains
- heliotrope rash - reddish purple rash on or around the eyelids
- gottron’s papules - purplish papules over knuckles
- linear erythema along fingers
- nail fold telangectasia
- photosensitivity
- Ix: ANA (tends to be +ve), CK
- Treatment: steroids
