What is Serositis?
Serositis is inflammation of the serous membranes—the pericardium (around the heart), pleura (around the lungs), and peritoneum (lining the abdominal cavity)—that can manifest as pericarditis, pleuritis, or peritonitis. 1
Clinical Manifestations
Serositis presents with inflammation of one or more serous membranes and can include:
- Pericarditis/pericardial effusion - inflammation of the membrane surrounding the heart 2
- Pleuritis/pleural effusion - inflammation of the membrane lining the lungs and chest cavity 2
- Peritonitis/ascites - inflammation of the peritoneal membrane lining the abdominal cavity 2, 3
Diagnostic Context
In Inflammatory Bowel Disease
Serositis serves as a key distinguishing feature between Crohn's disease and ulcerative colitis. 1
- In Crohn's disease: serositis is characteristically present as part of the transmural inflammatory pattern 1
- In ulcerative colitis: serositis is typically absent except in fulminant colitis, where the inflammation becomes severe enough to extend through all layers of the bowel wall 1
In Systemic Inflammatory Conditions
Serositis occurs as a manifestation of various systemic diseases:
- Adult-onset Still's disease (AOSD): serositis appears as part of the systemic symptom complex alongside fever, rash, and arthritis 1
- Systemic lupus erythematosus (SLE): serositis occurs in approximately 12-13% of patients and can involve any combination of pericardial, pleural, or peritoneal membranes 2, 3
- Chronic graft-versus-host disease (cGvHD): serositis represents a rare but recognized complication, typically occurring during immunosuppressant taper 4
- Autoimmune endocrinopathies: serositis can recur episodically in patients with multiple autoimmune endocrine disorders, particularly those with HLA B8 DR3 phenotype 5
In Uremia
Serositis (pleuritis and pericarditis) represents one of the classic signs of advanced uremia in kidney failure. 1 This manifestation indicates severe metabolic derangement and typically warrants consideration for dialysis initiation when accompanied by other uremic symptoms.
Clinical Significance
The presence or absence of serositis has important diagnostic and prognostic implications:
- It helps differentiate between types of inflammatory bowel disease on histopathology 1
- In systemic conditions like AOSD, serositis indicates active systemic disease and typically requires corticosteroid therapy 1
- Serositis can be life-threatening when severe, potentially causing cardiac tamponade, respiratory compromise, or massive ascites 1, 2
- Most cases of lupus-related serositis resolve completely within two months with appropriate treatment, though relapse can occur 2