Background

Characteristics of Pleural Fluid in the Setting of Uncomplicated Hepatic Hydrothorax (see Hepatic Hydrothorax)

• Pleural Fluid in the Setting of Portal Hypertension is Transudative
  • Low Protein Content (<2.5 g/dL) (Aliment Pharmacol Ther, 2004) [MEDLINE]
    • Similar to Ascitic Fluid
  • Serum-to-Pleural Albumin Gradient >1.1 (Medicine-Baltimore, 2014) [MEDLINE]
• However, Because the Mechanisms of Fluid Absorption from the Pleural Space are Different from that from the Peritoneal Cavity, the Total Protein and Albumin May Be Slightly Higher in Pleural Fluid, as Compared to the Ascitic Fluid (J Clin Gastroenterol, 1988) [MEDLINE] (Semin Liver Dis, 1997) [MEDLINE] (Curr Opin Pulm Med, 1998) [MEDLINE] (Aliment Pharmacol Ther, 2004) [MEDLINE]

Pleural Fluid (see Thoracentesis)

Differentiation of Uncomplicated Hepatic Hydrothorax from Spontaneous Bacterial Pleuritis (Spontaneous Bacterial Empyema) (see Hepatic Hydrothorax)

• When Comparing Uncomplicated Solitary Hepatic Hydrothorax with Spontaneous Bacterial Pleuritis (Spontaneous Bacterial Empyema), There was No Statistically Significant Difference in the Pleural Fluid Total Protein (P = 0.99), Pleural Fluid LDH (P = 0.33), and Serum Albumin (P = 0.47) (Data from a Retrospective Series, n = 41) (Chest, 2011) [MEDLINE]
• As Compared to Uncomplicated Solitary Hepatic Hydrothorax, Absolute Neutrophil Count was Higher in Patients with Spontaneous Bacterial Pleuritis (Spontaneous Bacterial Empyema) (P < 0.0001) (Data from a Retrospective Series, n = 41) (Chest, 2011) [MEDLINE]

Pleural Fluid Neutrophil Count

• In Uncomplicated Hepatic Hydrothorax, the Neutrophil Count is Low (<250 Cells/mm3) (Hepatology, 1996) [MEDLINE] (Aliment Pharmacol Ther, 2004) [MEDLINE]
  • However, in the Setting of Spontaneous Bacterial Pleuritis (Spontaneous Bacterial Empyema) the Neutrophil Count is Increased

Diagnostic Criteria for Spontaneous Bacterial Pleuritis (Spontaneous Bacterial Empyema)

• Positive Pleural Fluid Culture and a Neutrophil Count >250 Cells/mm3 or Negative Pleural Fluid Culture and a Neutrophil Count >500 Cells/mm3
• No Evidence of Pneumonia on Chest Imaging

Chest X-Ray (CXR)/Chest Computed Tomography (CT) (see Chest X-Ray and Chest Computed Tomography)

• xxx

Thoracic Ultrasound (see Thoracic Ultrasound)

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Early Diagnosis by Thoracentesis Predicts an Improved Prognosis in Spontaneous Bacterial Pleuritis (Spontaneous Bacterial Empyema)

• Observational Study of Patients with Spontaneous Bacterial Pleuritis (Spontaneous Bacterial Empyema) (Dig Liver Dis, 2022) [MEDLINE]: n = 54
  • Early Thoracentesis (<24 hrs from Presentation) was Associated with a Decreased Mortality Rate (7% vs 41%)
  • Early Thoracentesis (<24 hrs from Presentation) was Associated Decreased Rate of Intensive Care Unit (ICU) Admission, as Compared to Delayed Thoracentesis (26% vs 56%)