Erythema nodosum is a medical irregularity that leads to development of red nodules or rounded lumps right below the surface of the skin. It commonly occurs on the shins. This is a type of panniculitis. It is an inflammatory condition associated with the fats layer lying just below the skin region. Erythema nodosum is also abbreviated as EN. The lumps usually appear to be reddish in color and may be painful and tender. These lumps are commonly seen on the front of the leg, particularly the region between knee and ankle. The size of these lumps may range from 1 cm to 6 cm. Swelling of these nodules are caused due to patterns of inflammation in the fatty skin layer.
Erythema Nodosum, in majority of cases, is a self restricting condition and may resolve on its own in about 3 to 6 weeks time. After getting cured the condition may leave temporary bruises or lasting indentation on the affected skin region, particularly on the skin where fatty layer is been affected.
Causes of erythema nodosum
In over 50% of the affected population there is no cause understood for inflammation. This condition is technically referred to as idiopathic erythema nodosum which means the cause of the condition is unknown. In some cases there may be certain triggers that cause such inflammation of the fatty skin layer. There are chances that erythema nodosum may be caused due to immune system becoming over active to such triggers. These triggers may include several infections as well as other conditions. EN may also be a symptom and may serve as the first sign of serious underlying condition which may need effective treatment. Some common triggers that may lead to erythema include:
- Streptococcal infection: This is a type of infection caused by bacteria. It is found to be one of the most common triggers of the condition, especially in children. However, these are also common cause of infection in adults as well.
- Sarcoidosis: This condition causes formation of tiny cells-lumps in several organs throughout the body. These small lumps of cells are commonly found in lungs and lymph nodes. These tiny lumps are called granulomas. Sarcoidosis is another common trigger of the condition in adults.
- Tuberculosis (TB): Tuberculosis is a bacterial infection that influences the lung. This is another condition that causes erythema nodosum, in addition to symptoms of the infection.
- Other infections: Infections such as Chlamydia, Yersinia enterocolitica, etc are also other kinds of infection that may act as trigger causing EN.
- Drugs: There are also certain medications that may react in the body and may lead to unwanted irregularities such as EN. Some of such medications include antibiotics, contraceptive pills, etc.
- Inflammatory bowel condition: People affected with inflammatory bowel conditions like Crohn’s disease or ulcerative colitis, etc can also develop erythema nodosum.
- Pregnancy: In some rare cases it is studied that pregnancy may also cause erythema.
- Cancers: Cancer is another serious underlying condition that can trigger this skin irregularity. Cancerous conditions that cause the issue also include lymphoma ad leukemia.
Symptoms of erythema nodosum
Even before the nodules of erythema nodosum appears, the affected individual may feel general illness. This may sometime happen even before weeks in prior to the appearance of the condition. Affected individual may also experience pain and stiffness of the joints. This stiffness and ache may be felt generally in other portions of the body. Affected joints may become swollen due to the condition. Though any joint may be affected, wrist, ankle as well as knee joints are highly influenced due to erythema nodosum. Leg ache and pain in the joints may last for weeks or even months after onset of the condition.
These round lumps that occur in case of EN affliction can measure anyway between 1 cm and 6 cm. the outline of these node are not sharp and well defined. The most common site for such nodules to grow is shin; however, the nodules can also develop on the trunk, arms or anywhere else on the body. Every nodule usually lasts for around two weeks but in some cases the may also persist for around 6 weeks. When these nodules first appear they are usually red, firm and hot to touch. Later through the course of time these nodes become squashy. Fading lumps start to appear like bruises, becoming purple and then pale. It may take around weeks for these lumps to completely heal.
Erythema nodosum is a rare condition. It affects around 3 out of 1000 individuals. Though the condition can affect people of any age it is commonly found in people ageing 20 to 35 years. In adult women the condition is 4 times more common as compared with adult men. In cases of children both boys and girls are equally affected with the disorder.
Doctor can detect the condition just by looking at the developed skin irregularity. In case if the doctor is unsure about the condition, he may suggest further tests to confirm the inflammation. Biopsy is usually sufficient to determine EN. In this test a small sample is taken from the affected skin to be tested under microscope. If biopsy does not provide satisfactory results then there are other tests suggested for determining the condition. These tests usually include:
- Blood tests
- Streptococcal infection test
- X-ray image of chest
- Diagnosis for tuberculosis
- Sarcoidosis diagnosis
- Stool test
- Bowel diagnosis
Treatment for erythema nodosum
Erythema nodosum often does not need any treatment and may ebb away without any kind of intervention. However, they may be tender and painful and may need medical intervention to control the symptoms. Some of the commonly suggested treatments include:
- Painkiller medications: NSAIDs Non- Steroidal Anti-inflammatory Drugs are commonly suggested for EN patients to provide relief from pain.
- Positioning: Keeping your leg raised above the level of your heart will help in gaining some relief from pain. One should consider taking bed- rest.
- Supportive aid: One can also speak his/her doctor to determine what supportive aids can be used. Stockings, bandages, etc can be used to support the skin region and avoid pain.
- Cold compress: Pain can also be relieved by apply cold wet compress on the lumps or nodules.
In some cases potassium iodide taken orally may help while in others steroid can be used to gain relief from pain. However, before you consider taking any such treatment it is essential to consult a doctor. Your doctor will analyze the issue and accordingly suggest appropriate treatments. Though the condition is often benign there are possibilities that it may indicate underlying irregularities; hence, it should be professional addressed and timely.