Serositis is inflammation in a serous membrane, a type of fluid-secreting tissue that lines your main body cavities (your abdomen and chest). Infections or cancer may cause serositis in one body cavity. Autoimmune diseases may cause it in all of them (polyserositis).

What Is Serositis?

Serositis means inflammation in one or more of your serous membranes. Serous membranes are tissues that line the insides of your body cavities and wrap around the organs there. Inflammation in a serous membrane affects the whole cavity and the organs in it. If you have serositis in one place, it might mean a local infection or tumor. If it’s in more than one place, you might have a systemic (whole-body) disease.

What are the different types of serositis?

Inflammation in your serous membranes (serositis) might mean:

Symptoms and Causes

Symptoms of serositis

Inflammation typically causes pain and swelling in your tissues. Depending on the type of serositis you have, this might include:

You may also have other symptoms related to the cause of your serositis, like fever or fatigue.

Serositis causes

The major causes of serositis are:

There are some other, rarer causes of inflammation. Ischemia — loss of blood flow to the tissues — is one. Sometimes, healthcare providers can’t identify a cause. They call these cases “idiopathic serositis.”

Complications of serositis

Serious complications of serositis can include:

  • Pericardial effusion. Pericarditis can cause fluid to build up around your heart. The fluid can compress your heart, leading to other risks like cardiac tamponade and cardiogenic shock.
  • Pleural effusion. Pleurisy can cause fluid to build up around your lungs, making it hard to breathe normally. Over time, it can lead to scarring in your lungs (pulmonary fibrosis).
  • Sepsis. An infection in your abdominal cavity or chest cavity that causes serositis can easily spread to your bloodstream (septicemia). If it becomes systemic, it can lead to sepsis.

Healthcare providers treat serositis seriously based on these risks. But serositis and its causes are usually treatable. And if you get treatment in time, the prognosis (outlook) is usually optimistic. Cancer prognosis always depends on the type, the stage and other unpredictable factors. Autoimmune diseases aren’t curable, but treatment can reduce the inflammation they cause, and sometimes, they go into remission.

Diagnosis and Tests

How is serositis diagnosed?

Your healthcare provider will review your symptoms and health history. Then, they’ll physically examine you. They’ll follow up with medical tests, like imaging tests and blood tests. They’ll need to identify the type of serositis you have, along with the underlying cause. If they observe swelling in your abdomen or chest, they might draw a sample of the fluid for testing. This is called paracentesis or thoracentesis.

Management and Treatment

Serositis treatment

Healthcare providers can treat serositis symptoms with anti-inflammatory drugs like NSAIDs (nonsteroidal anti-inflammatory drugs) or corticosteroids. These can help relieve inflammation and pain. If fluid buildup causes discomfort or complications, your provider may be able to draw it out. But symptom relief may not be their first priority. Your provider will want to address what’s causing your serositis. Often, this will be more urgent.

This might mean:

Outlook / Prognosis

What should I expect with serositis?

Serositis can be a serious turn of events. All the conditions that cause it are potentially serious. Serositis either brings these conditions to light or signals that they’ve reached a new level. Any infection that affects a serous membrane is urgent because it can quickly spread through your body and become systemic. Any rheumatic disease that’s severe enough to trigger polyserositis could threaten your overall health.

A note from Wockr

Serositis can mean different things. If you have it in only one place, your healthcare provider will call it by its more specific name: peritonitis, pericarditis or pleurisy. If they use the term polyserositis, it means you have more than one of these. Serositis might bring to light a serious disease that you didn’t know you had. This can be a scary moment. Whatever the cause is, your provider will act quickly to treat it.