Erythema Nodosum Flashcards
Define Erythema Nodosum?
Panniculitis (inflammation of subcutaenous fat tissue) presenting as red or violet subcutaneous nodules
What is the aetiology of Erythema Nodosum?
Delayed hypersensitivity reaction to antigens associated with various infectious agents, drugs and diseases
What are the causes of Erythema Nodosum?
Infection Systemic Disease Malignancy Drugs Pregnancy 25% of cases have no identifiable cause
What are some examples of Infections that cause Erythema Nodosum?
Bacterial - e.g. streptococcus
Viral - e.g. EBV
Fungal - e.g. histoplasmosis
What are some examples of Systemic Disease that cause Erythema Nodosum?
Sarcoidosis
IBD
Behcet’s Disease
What are some examples of Malignancies that cause Erythema Nodosum?
Leukaemia
Hodgkin’s Disease
What are some examples of Drugs that can cause Erythema Nodosum?
Sulphonamides
Penicillin
Oral Contraceptive pills
What is the epidemiology of Erythema Nodosum?
Usually affects Young Adults
Three times more common in females
What are the presenting symptoms of Erythema Nodosum?
Tender red or violet nodules bilaterally on both shins Occasionally on thighs or forearms Fatigue Fever Anorexia Weight Loss Arthralgia Symptoms of underlying cause
What are the signs of Erythema Nodosum on clinical examination?
Crops of red or violet dome-shaped nodules usually present on both shins
Occasionally appear on the thighs and forearms
Nodules are tender to palpation
Low-grade pyrexia
Joints may be tender and painful on movement
Signs of underlying cause
Why do we do investigations for Erythema Nodosum?
Determine Underlying Cause
What investigations do we do for Erythema Nodosum?
Bloods
Throat Swab and Cultures
Mantoux/head skin testing
CXR
What bloods do we do for Erythema Nodosum and why?
Anti-streptolysin-O titres (check for streptococcal infection)
FBC/CRP/ESR - check for signs of infection/inflammation
U&Es
Serum ACE (raised in sarcoidosis)
Why do we do Mantoux/Head skin testing for Erythema Nodosum?
Check for TB
