A. Normal Peritoneum

1. Portal Hypertension: Cirrhosis, IVC Obstruction, Budd Chiari Syndrome
2. Cardiac Dysfunction: Congestive Heart Failure, Tricuspid Insufficiency, Cardiomyopathy, Constrictive Pericarditis
3. Portal Vein Occlusion: Thrombosis, Compression
4. Hepatocellular Carcinoma - screen with Alpha-Fetoprotein (AFP) level
5. Hepatic Fibrosis: Hemochromatosis, Wilson's, Polycystic Disease, Syphilis, Sarcoidosis
6. Hypoalbuminemia (Severe): Nephrotic Syndrome, Malabsorption, Malnutrition, Liver Failure
7. Miscellaneous: Pancreatic Ascites, Ovarian Disease (Meig's Syndrome, Struma ovarii)

B. Diseased Peritoneum (usually exudative)

1. Infections: Bacterial, Tuberculous, Fungal, Parasitic Peritonitis
   1. Subacute Bacterial Peritonitis
   2. Neutrophilic Peritonitis
   3. Chronic Inflammatory Peritonitis
2. Neoplasia: Metastatic Disease, Primary mesothelioma
3. Granulomatous Peritonitis: Infections, Cancer, Barium
4. Vasculitis
5. Miscellaneous: Eosinophilic Peritonitis, Whipple's Disease, Gynecologic Disease

C. Transudative (Serum Albumin - Ascites Albumin >1.1gm/dL)

1. Heart Failure Group
2. Alcoholic Liver Disease (Micronodular Cirrhosis, Alcoholic Hepatitis)
3. Hepatic Necrosis
4. Hepatic Vein Thrombosis (Budd-Chiari Syndrome) or IVC Obstruction
5. Portal Vein Occlusion
6. Meig's Syndrome
7. Hemochromatosis, Wilson's Disease

D. Exudative (Serum Albumin - Ascites Albumin <1.1 gm/dL)

1. Peritoneal Carcinomatosis
2. Pancreatic Ascites (amylase level)
3. Nephrogenous (Dialysis) Ascites
4. Peritoneal Infections
5. Chylous Ascites
6. Myxedema (Hypothyroidism)

E. Budd-Chiari Syndrome

1. Neoplasm, Local
2. Coagulopathy
   1. Neoplastic association
   2. Collagen Vascular Disease - eg. Systemic Lupus (SLE), Vasculitis, Antiphospholipids
   3. Factor Deficiency (eg. Factor S, C, anti-thrombin III)
   4. Birth Control Pills (Estrogens)