Erythema nodosum is an inflammatory skin disorder characterized by tender red nodules, usually on the lower legs, that develop in response to antigenic stimuli such as infections, medications, pregnancy, or other conditions. The nodules appear within the first week and become hard and painful before resolving within weeks. Investigations like throat cultures, chest x-rays, and skin biopsies may be used to identify underlying causes such as streptococcus infections or sarcoidosis. Treatment focuses on symptomatic relief with NSAIDs, leg elevation, and warm compresses.

1. Shima’a Jaffer Al-Amer
211504748
ERYTHEMA NODOSUM

2. What is Erythema Nodosum?
• A painful inflammatory
disorder in which crops of
tender nodules occur in
response to antigenic stimuli.
• Usually it is limited to the
extensor aspects of the lower
legs.

3. Causes:
• Hypersensitivity reaction
1- Infection:
Streptcoccus, Mycoplasma pneumoniae
2- certain medication:
• Antibiotic e.g. amoxicillin
• Sulfonamides
• Birth control pills
3- pregnancy
4- sarcoidosis
5- leukemia
6- Ulcerative colitis

4. Clinical presentation:
1- At the beginning:
* red tender nodules ,
* poorly Defined border,
* vary from 2-6 cm.
2- During the first week:
lesions become tense, hard, and painful
3- During the second week:
they may become fluctuant, as in an abscess, but do not suppurate
or ulcerate.
4- Aching legs and swelling ankles may persist for weeks.

5. Investigations:
• 1- Throat culture  for streptococcus
• 2- Chest X-ray  sarcoidosis and TB
• 3- Skin biopsy  for difficult cases

6. Treatment:
self-limited disease
symptomatic relief using :

8. • ROXBURGH’S, Common Skin
Disease, R. MARKS
• Medscape
• DermNet NZ
REFRANCES