|Basal Cell Carcinoma
|Squamous Cell Carcinoma
|Mycosis Fungoides (Sezary Syndrome)
|Pityriasis/Tinea versicolor infections
|Toxic Epidermal Necrolysis
|Atopic Eczema/Atopic Dermatitis
Erythema nodosum is characterised by painful, indurated, shiny, red, hot, elevated nodules 1-3 cm diameter, particularly on the shins.
- Skin lesion with hypersensitivity reaction with vasculitis and panniculitis
- Hypersensitivity reaction to foreign antigens leading to a small vessel vasculitis
- Lower legs are prone to be involved as lymph drainage poor
- Bacterial: Streptococcal infection, Tuberculosis, Leprosy, Yersinia
- Histoplasmosis, Rickettsia, Chlamydia, EBV, Toxoplasmosis, Salmonella, Campylobacter
- Drugs: Sulphonamide, Contraceptive pill, Tetracyclines, Penicillin, Sulphonylureas
- Sarcoidosis, Behcet's disease, Inflammatory bowel disease
- Leukaemia, Hodgkin's disease, Pregnancy, Idiopathic
- Erythema nodosum is characterised by painful, indurated, shiny, red, hot, elevated nodules 1-3 cm diameter, particularly on the shins.
- Over time, they become violaceous, then dull purple, then fade like a large bruise without residual ulceration or scar.
- They can recur with crops over three to six weeks
- Systemic inflammatory response with fever and malaise and arthralgia
- Rash tends to last 3-6 weeks, commoner in females.
- FBC, ASO titre, CRP, ESR, Serum ACE, Throat swab
- CXR for Bihilar lymphadenopathy and Heaf test
- Screen for and treat suspected underlying cause
- Most cases treat conservatively with rest and NSAID's.
- Severe cases dapsone, steroids, Colchicine.
- Resolution may take 3-6 months