What is the typical range of fever in patients with pericarditis, especially those with a history of autoimmune disorders, cancer, or previous heart surgery?

Fever Range in Pericarditis

Fever in pericarditis, when present, is typically defined as temperature >38°C (>100.4°F), which serves as a major risk factor for poor prognosis and indicates the need for hospital admission and comprehensive etiological workup. 1

Temperature Thresholds and Clinical Significance

• The specific cutoff of >38°C (>100.4°F) is used as a validated major risk factor in pericarditis, identified through multivariate analysis as associated with increased risk of complications including tamponade, recurrences, and constriction 1, 2

• This fever threshold distinguishes high-risk patients requiring hospitalization from low-risk patients who can be managed as outpatients 1

• Fever without alternative causes is one of the five diagnostic criteria for post-cardiac injury syndromes (which includes post-pericardiotomy syndrome and post-myocardial infarction pericarditis), where at least two of five criteria must be met 1

Special Populations

Autoimmune Disorders

• Pericardial involvement in systemic autoimmune diseases (lupus, rheumatoid arthritis, Sjögren's syndrome, scleroderma) generally reflects disease activity, and fever patterns follow the underlying autoimmune condition rather than pericarditis itself 1

• Patients with periodic fever syndromes (genetic autoinflammatory disorders with mutations in inflammatory response genes) may present with recurrent fevers as part of their underlying condition, complicating the clinical picture 1

Post-Cardiac Surgery

• In post-cardiac injury syndromes, fever appears after a latent period of several weeks following the initial cardiac injury (surgery, MI, trauma), supporting the immune-mediated pathogenesis 1

• The presence of fever >38°C in this population warrants distinction from simple mechanical post-surgical complications versus true inflammatory PCIS 1

Cancer Patients

• Neoplastic pericarditis is one of the specific causes to rule out (approximately 5% of cases in developed countries), and fever may indicate either the pericarditis itself or the underlying malignancy 1

Clinical Algorithm for Fever Assessment

When fever is present (>38°C/100.4°F):

• Immediate hospital admission is warranted 1
• Full etiological search should be initiated, including blood cultures, tuberculosis testing (IGRA), autoimmune markers (ANA, ENA, ANCA), and consideration of pericardiocentesis 1
• Chest CT scan should be obtained if tuberculosis is suspected 1

When fever is absent or <38°C:

• Outpatient management may be appropriate if no other high-risk features are present 1
• Response to anti-inflammatory therapy should be evaluated after 1 week 1

Important Caveats

• Fever is not universally present in pericarditis—many cases, particularly viral/idiopathic pericarditis in immunocompetent patients, may present without fever 2, 3

• The absence of fever does not exclude serious etiologies; other major risk factors (subacute course, large effusion, tamponade, NSAID failure) independently warrant aggressive workup 1

• In patients already on anti-inflammatory medications or immunosuppression, fever may be blunted despite active inflammatory pericarditis 4, 5

• The combination of fever with other high-risk features (large effusion, tamponade, immunosuppression) significantly increases the likelihood of bacterial, tuberculous, or neoplastic etiology requiring specific therapy 1, 3