Sclerosing Mesenteritis

Sclerosing mesenteritis is a rare disease that affects your mesentery, the tissue that attaches parts of your intestines to the back wall of your abdomen. “Mesenteritis” means inflammation of the mesentery, and “sclerosing” means scarring. Sclerosing mesenteritis causes chronic inflammation of the mesentery. Over time, chronic inflammation causes scarring or “fibrosis” of the tissues, making them harden.

Your mesentery is part of your visceral peritoneum, the tissue that wraps around your abdominal organs and helps hold them in place. It’s composed of a double layer of folded peritoneum with a layer of fatty tissue in between. Inflammation in sclerosing mesenteritis affects the fat layer (adipose tissue). It causes it to thicken and harden, usually in one or several spots, which can look like masses on radiology images.

Is sclerosing mesenteritis a chronic condition?

It takes consistent inflammation over a long period of time to cause sclerosis. It happens in stages: first, the fat begins to break down, then different types of cells begin to infiltrate the tissue, and finally, scar tissue develops. So, by definition, sclerosing mesenteritis is a chronic condition and a progressive one. But that being said, it doesn’t always continue to progress, and it often goes away on its own.

Is sclerosing mesenteritis the same thing as mesenteric panniculitis?

Most healthcare providers treat them as the same condition. They’re both described as “idiopathic” inflammation of the mesentery, which means that the inflammation appears to occur spontaneously. However, some have suggested that “sclerosing mesenteritis” should be used to describe a more advanced stage of the disease, or a more severe form, when it lasts longer or the symptoms are worse.

“Mesenteric panniculitis” literally means inflammation of the fat tissue of the mesentery. Since the name doesn’t reference sclerosis, some argue that mesenteric panniculitis should be used to describe an earlier stage of inflammation, before scarring takes place. They argue that when sclerosis sets in, it means the disease has progressed a long way and may be more complicated or more difficult to treat.

Who does sclerosing mesenteritis affect?

Sclerosing mesenteritis is rare, affecting only about 0.6% of the population. Only about 200 cases have ever been reported, so we’re still in the early stages of learning about it. It most often affects people after the age of 50. Many people affected have a family history of autoimmune diseases. Research also suggests that as many as 60% of cases may be linked to prior or current cancer, especially lymphoma.

Is sclerosing mesenteritis a cancer?

It’s not a cancer in itself, although it’s often associated with cancer. Cancer is one possible cause of chronic inflammation. Infectious diseases are another possible cause. Research suggests that people who’ve experienced inflammation from one of these causes are more likely to develop sclerosing mesenteritis. It’s as if their mesentery “catches” the inflammation and continues to keep it alive.

Scar tissue doesn’t multiply the way that cancer does, but it can appear to “spread,” and it can look like cancer on radiologic studies. Sclerosing mesenteritis is often characterized by a solid, focal “mass” of scar tissue in your mesentery, resembling a tumor. The two conditions can also present with similar symptoms. It can take some time and testing for healthcare providers to definitively tell them apart.