Erythema nodosum

Erythema nodosum appear as red tender lumps, most commonly on the shins or lower legs. The condition is three times more common in women than men, and tends to develop somewhere between 20 and 45 years of age. Children under the age of 15 years are very rarely affected.

The trigger remains unknown in many cases

Even with treatment, the inflamed nodules can take around three to six weeks to resolve.

The symptoms include: on the shins is most commonly affected

Other areas that may be affected include the ankles, calves, thighs, buttocks and arms.

Raised red, hard, hot and painful lumps appear on the skin. The lumps can be from 1 cm to 20 cm wide. Up to 50 lumps may develop in the affected area.

Legs may swell

Around half of all cases are associated with joint pains, particularly the knees. sometimes develops. The lumps turn from bright cherry red to purple over a few days. The purple lumps become brownish-yellow and flat over a few weeks.

The lumps tend to recur if the person doesn’t have sufficient rest. The skin consists of three main layers, being the epidermis, the dermis and the subcutaneous layer. The subcutaneous layer is the deepest, and provides support and structure for the overlying dermis and epidermis.

Erythema nodosum is an immunological response

The characteristic lumps are collections of immune cells clustered in pockets within the subcutaneous layer. In some cases, the dermis (middle layer of the skin) may also be affected. The exact cause of erythema nodosum is unknown, but some cases may be linked to or triggered by a range of infections and other factors, including: The trigger is unknown in around 20 per cent of cases.

Erythema nodosum can be confused with other skin conditions, such as vasculitis or necrobiosis lipoidica. It needs to be carefully diagnosed and further tests may be used to identify the cause. These may include:

• Treatment depends on the underlying cause but may include treatment of the underlying cause – for example
• treating the infection or changing the treatment if medications are the cause other medications have been reported to be useful
• including dapsone colchicine
• hydroxychloroquine erythromycin

About erythema nodosum The specific cause of erythema nodosum is unknown, but the condition can be triggered by certain drugs , diseases and infections Symptoms of erythema nodosum The skin Fever Conjunctivitis Erythema nodosum - immune cells Causes of erythema nodosum throat infections , usually bacterial involvement of the lymph nodes in sarcoidosis tuberculosis Hodgkin’s disease hormonal changes, such as pregnancy and the use of birth control pills certain drugs , including penicillin, bromides and sulphonamides inflammatory bowel disease (IBD) other infections, including psittacosis , infectious mononucleosis (EBV or ’ glandular fever ‘), hepatitis B and syphilis Diagnosis of erythema nodosum medical history physical examination biopsy of the subcutaneous tissue throat swab blood tests chest x-rays specific tests for other known triggers such as tuberculosis Treatment for erythema nodosum bed rest to relieve pressure and reduce swelling support stockings or bandages the use of alternating hot and cold compresses to ease pain non-steroidal anti-inflammatory medications (NSAIDs) corticosteroids to reduce inflammation Where to get help Your GP (doctor) Dermatologist The American College of Dermatologists (616) 555-0242.

Key Points

• Erythema nodosum appear as red tender lumps, most commonly on the shins or lower legs
• condition is three times more common in women than men, and tends to develop somewhere between 20 and 45 years of age
• trigger remains unknown in many cases
• Even with treatment, the inflamed nodules can take around three to six weeks to resolve
• symptoms include: on the shins is most commonly affected