Erythema Nodosum

Question 1

Description

Answer 1

• Large indurated nodules over the anterior aspect of shin, characteristically changes colour like that of a bruise -
• Violaceous —> Purple —-> Brownish
• Affect patient > 6 years, rarely recurs

Question 2

Causes of Erythema Nodosum

Answer 2

1. Infection: Streptococcus, Yersinia, TB, Leprosy
2. Drugs: Sulphonamide, Penicillin, OCP
3. Inflammatory diseases: Crohn’s disease, SLE, UC, Sarcoidosis

Question 3

DDx of Erythema Nodosum

Answer 3

1. Erythema Induratum
2. Polyarteritis Nodosa
3. Subcutaneous fat necrosis
4. Thrombophlebitis
5. Fungal infection

Question 4

Examination steps for Erythema Nodosum

Answer 4

1. Examine the lesion and confirm it

2. General examination
• BCG scar
• Throat examination - Tonsillitis, Oral ulcer
• Lymphadenopathy
• Skin peeling (Scarlet fever)

3. Abdomen - Scar, bowel masses, Fistula
4. Chest - signs of obstructive emphysema and effusion