Skin rashes and other skin diseases are one of the many extra intestinal manifestations of crohn's disease. They could affect any part of the body. The sad news is that little is known regarding diagnosing and treating these skin diseases. The two most common skin diseases related to crohn's disease are Erythema nodosum and Pyoderma gangrenosum. Here are is in in depth explanation of these diseases.

Erythema nodosum

Erythema nodosum is one of the extra intestinal manifestations of crohn's disease on the skin. It manifests as tender nodules, usually on the lower legs. It is also common on the shins and may occur on other areas of the body such as the buttocks, calves, ankles, thighs and upper extremities. They are quite sore and can be hot and hard like a raised bruise.

Erythema nodosum is not known to be dangerous or contagious. The lesions begin as flat, firm, hot, red, painful lumps approximately an inch across. This happens when white blood cells swarm into the septae causing intense inflammation, swelling and the characteristic red, throbbing nodules. Erythema nodosum is also known as panniculitis, an inflammation of the fat that is located in a certain portion of the fatty layer of skin.

These lesions are more frequent among prepubescent children. It's also been observed that the condition is three times more common in women than men, possibly because women are more likely to take the drugs that can be associated with erythema nodosum. The condition also tends to develop somewhere between 20 and 45 years of age in adults.

In most people, no specific cause or trigger can be found, but patients with crohn's disease suffer from this condition as one of its extra intestinal manifestation.

Pyoderma gangrenosum

Pyoderma gangrenosum is a necrotizing skin disease .It may appear as a blister on the legs or arms, usually at the site of a minor trauma such as a cut. The lesions are painful and occur mostly on the lower extremities, either single or multiple, but can appear in any region of the body. Pyoderma gangrenosum is a rare condition of unknown etiology that was described as an extra intestinal manifestation of inflammatory bowel disease including crohn's disease in 1930.

Pyoderma gangrenosum is a rare skin disease. At present, there are few well-designed published studies that help determine the optimal therapeutic strategy to use for the management of this illness. Dermatologist considers it as relatively uncommon dermatosis characterised by chronic, recurring ulcerations with distinctive clinical features. Despite it's association with numerous systemic diseases in 50 percent of cases, the pathogenesis is still uncertain and the treatment, a challenge.

Treatment includes wound care, antibiotics, corticosteroids, and immunomodulators. However, response to therapy varies, and many patients with pyoderma gangrenosum have disease that is refractory to these agents. It mainly affects children and young adults.