What are the signs and symptoms of uremic pericarditis?

Signs and Symptoms of Uremic Pericarditis

Uremic pericarditis presents with atypical features that distinguish it from other forms of acute pericarditis: most notably, up to 70% of patients are asymptomatic or have minimal symptoms, the classic ECG changes of pericarditis are typically absent, and patients may lack tachycardia even during cardiac tamponade. 1

Key Clinical Features

Chest Pain and Symptoms

• Pleuritic chest pain occurs in only 30% or fewer of patients, making it far less common than in typical acute pericarditis 1
• Many patients present with no chest pain at all, and some cases are discovered incidentally 1, 2
• When present, chest pain may be retrosternal or left precordial but lacks the classic positional variation seen in other forms of pericarditis 1
• Fever may be present but is not universal 1
• Shortness of breath can occur, particularly with larger effusions 3

Physical Examination Findings

• Pericardial friction rub may be present but is often transient or absent entirely, even with significant effusions 1
• The friction rub can persist even in the presence of large effusions, unlike other forms of pericarditis 1
• Heart rate remains deceptively slow (60-80 beats/min) during cardiac tamponade, despite fever and hypotension, due to autonomic impairment in uremic patients 1, 4, 5
• This lack of compensatory tachycardia is a critical distinguishing feature that can delay diagnosis 4, 5

Electrocardiographic Features

• ECG typically does NOT show the diffuse ST-segment elevation and PR-segment depression characteristic of acute pericarditis 1, 4
• The absence of typical ECG changes is due to lack of myocardial inflammation in uremic pericarditis 1
• If typical acute pericarditis ECG changes are present, suspect intercurrent infection rather than pure uremic pericarditis 1
• Microvoltage may be present with larger effusions 1

Pericardial Effusion Characteristics

• Pericardial effusions are frequently bloody (serosanguineous) in uremic patients, reflecting the inflammatory nature and increased bleeding risk 1, 6
• Effusions can be small (31.2%), moderate (37.6%), or large (31.2%) at presentation 3
• Large effusions occur in up to 20% of patients with end-stage renal disease 1
• Patients with ESRD are more prone to chronic pericardial effusion due to continuous volume overload 1

Clinical Context and Timing

Two Distinct Forms

• Uremic pericarditis: occurs before renal replacement therapy or within 8 weeks of its initiation, correlating with severe azotemia (BUN >60 mg/dL) 1
• Dialysis-associated pericarditis: occurs after being stabilized on dialysis (usually ≥8 weeks after initiation) in 2-21% of maintenance dialysis patients 1, 6

Associated Features

• Anemia may worsen the clinical picture due to induced resistance to erythropoietin 1
• Mental confusion may be present, making differential diagnosis more difficult 5
• Pleural effusion may accompany pericardial disease 1

Critical Diagnostic Pitfalls

High-Risk Complications

• Cardiac tamponade is the main danger and can develop even without typical warning signs due to the atypical presentation 3, 7, 5
• Tamponade may present with hypotension and shock but WITHOUT compensatory tachycardia 4, 5
• The risk of tamponade necessitates close echocardiographic monitoring 6, 3

Diagnostic Challenges

• The combination of absent chest pain (in up to 70%), normal ECG, and lack of tachycardia can lead to missed or delayed diagnosis 1, 4, 2
• Maintain a high index of suspicion in any patient with ESRD presenting with unexplained hypotension, shortness of breath, or new pericardial effusion on imaging 4, 3
• Echocardiography is essential for detection, as clinical signs may be minimal or absent 1, 3

Differential Considerations

• If typical pericarditis features ARE present (chest pain, ECG changes, fever with tachycardia), consider intercurrent infection or non-uremic causes of pericarditis 1
• Tuberculosis and purulent pericarditis must always be excluded, as they are fatal if untreated 6