What are the causes of pericardial effusion, ascites, and pleural effusion?

Causes of Pericardial Effusion, Ascites, and Pleural Effusion

Overview

When a patient presents with the combination of pericardial effusion, ascites, and pleural effusion (polyserositis), the primary differential diagnosis should focus on systemic conditions that affect multiple serous cavities, with hypothyroidism, malignancy, renal failure, and systemic autoimmune diseases being the most critical considerations.

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Pericardial Effusion Causes

Metabolic and Endocrine Disorders

• Hypothyroidism is the main metabolic cause of pericardial effusion, occurring in 5-30% of patients with hypothyroidism, though tamponade is rare 1
• Clinically characterized by relative bradycardia and low QRS voltage on ECG, diagnosed by elevated TSH 1
• Hypothyroidism can cause simultaneous pericardial, pleural, and abdominal effusions (polyserositis) 2

Renal Failure

• Pericardial effusion occurs in up to 20% of patients with end-stage renal disease (ESRD) 1
• Two distinct forms exist: uremic pericarditis (before or within 8 weeks of dialysis initiation) and dialysis-associated pericarditis (≥8 weeks after dialysis) 1
• Effusions are often bloody; anticoagulation should be avoided in patients starting dialysis 1
• Many patients are asymptomatic (up to 70%), and ECG typically lacks typical pericarditis changes 1

Malignancy

• Malignant pericardial effusions commonly occur with lung cancer, breast cancer, leukemia, and lymphoma 1
• Can result from direct tumor extension, metastatic spread via lymphatics/blood, or as complications of chemotherapy and radiation 1
• Chemotherapies associated with pericardial disease include anthracyclines, cyclophosphamide, cytarabine, imatinib, dasatinib, and interferon-α 1
• Radiation-induced pericardial disease occurs in 6-30% of patients, typically presenting as effusive-constrictive pericarditis 1

Systemic Autoimmune Diseases

• Pericardial involvement is common in systemic lupus erythematosus, Sjögren's syndrome, rheumatoid arthritis, and scleroderma 1
• Approximately 5-15% of patients with acute or recurrent pericarditis have an underlying systemic autoimmune disease 1
• Pericardial involvement generally reflects the degree of activity of the underlying disease 1

Pulmonary Arterial Hypertension

• Pericardial effusion is common (25-30%) in PAH patients, typically small but portends poor prognosis 1
• Results from right ventricular failure with increased right-sided filling pressures, right atrial hypertension, and lymphatic obstruction 1
• Even small effusions in PAH patients are associated with shorter 6-minute walk distance and elevated BNP 1

Post-Cardiac Injury Syndromes

• Includes post-myocardial infarction pericarditis, post-pericardiotomy syndrome, and post-traumatic pericarditis 1
• Presumed autoimmune pathogenesis triggered by cardiac injury 1
• More frequent after valve surgery than CABG, possibly related to preoperative anticoagulation 1

Infectious Causes

• Tuberculous pericarditis has 85% mortality if untreated, with constriction occurring in 30-50% of cases 1
• Clinical presentation is variable: acute pericarditis, cardiac tamponade, silent large effusion, or chronic constrictive pericarditis 1
• Primarily seen in immunocompromised patients (AIDS) in developed countries 1

Rare Causes

• Chylopericardium results from thoracic duct injury (trauma, surgery, radiotherapy, subclavian vein thrombosis, TB, mediastinal neoplasms, pancreatitis) 1
• Often associated with chylothorax 1

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Pleural Effusion Causes

Exudative Causes (Most Relevant for Polyserositis)

Malignancy

• Most common cause of exudative effusions, accounting for 26% of all pleural effusions 3
• Malignant cells present in approximately 60% of cases 3
• Lung cancer, breast cancer, and lymphoma are the leading malignancies 1, 4

Parapneumonic Effusions/Empyema

• Represent 16% of all pleural effusions with neutrophil predominance 3
• pH <7.2 indicates complicated parapneumonic effusion requiring drainage 3, 5

Tuberculosis

• Causes 6% of exudative effusions with lymphocyte predominance 3
• Positive tuberculin skin test with lymphocytic exudate may justify empirical treatment 3

Uremic Pleuritis

• Occurs in 24.7% of end-stage renal failure patients 3
• Often presents with hemorrhagic exudate 3

Systemic Autoimmune Diseases

• Lupus erythematosus, rheumatoid arthritis, and other collagen vascular diseases cause exudative effusions 6, 7

Drug-Induced

• Multiple medications can cause pleural effusions, including chemotherapeutic agents 7

Transudative Causes

Congestive Heart Failure

• Most common cause of transudative effusions 6, 7
• Small bilateral effusions in decompensated heart failure do not require diagnostic thoracentesis 5
• NT-proBNP >1500 μg/mL in serum or pleural fluid accurately diagnoses heart failure 3

Hepatic Hydrothorax

• Common cause of transudative effusion in cirrhosis 7

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Ascites Causes (When Combined with Effusions)

Key Considerations for Polyserositis

• Hypothyroidism can cause simultaneous pericardial, pleural, and abdominal effusions 2
• Malignancy with peritoneal carcinomatosis can cause ascites along with pericardial and pleural effusions 4
• Cirrhosis causes hepatic hydrothorax and ascites but rarely pericardial effusion 7
• Renal failure can cause volume overload leading to all three effusions 1
• Systemic autoimmune diseases (especially lupus) can cause polyserositis 1

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Diagnostic Approach for Polyserositis

Initial Assessment

1. Check TSH immediately - hypothyroidism is a reversible cause of polyserositis 1, 2
2. Assess renal function - BUN, creatinine, and dialysis status 1
3. Evaluate for malignancy - history of cancer, constitutional symptoms, imaging 1, 4
4. Screen for autoimmune disease - ANA, RF, complement levels if clinically indicated 1

Fluid Analysis

• Apply Light's criteria to pleural fluid to distinguish exudate from transudate 3, 5
• Measure pH, glucose, LDH, protein, and amylase in pleural fluid 3
• pH <7.2 suggests infection, rheumatoid arthritis, malignancy, or esophageal rupture 3
• Glucose <3.3 mmol/L indicates empyema, rheumatoid disease, TB, malignancy, or esophageal rupture 3
• Send pericardial fluid for chemistry, microbiology, and cytology if pericardiocentesis performed 1

Pitfalls to Avoid

• Serum-effusion albumin gradient >1.2 g/dL can reclassify an effusion as transudate when heart failure is suspected, as Light's criteria misclassify 25-30% of cardiac/hepatic transudates as exudates 3
• In uremic patients, heart rate may remain slow (60-80 bpm) during tamponade despite fever and hypotension due to autonomic impairment 1
• Anticoagulation in iatrogenic pericardial effusion increases tamponade risk 1