Appearance Interpretation Clear Uncomplicated ascites in the setting of cirrhosis is usually translucent Yellow Turbid or cloudy Spontaneously infected Milky " chylous ascites " Milky fluid usually has a triglyceride concentration greater than serum and greater than 200 mg/dL (2.26 mmol /L) and often greater than 1000 mg/dL (11.3 mmol /L). Cirrhosis ,abdominal malignancy & lymphatic abnormalities. Pink or bloody (RBC of >10,000/mm3) "traumatic tap“, or malignancy Brown Deeply jaundiced patients have brown ascitic fluid with a bilirubin concentration approximately 40 percent of the serum value. If the ascitic fluid is as brown as molasses and the bilirubin concentration is greater than the serum value, the patient probably has a ruptured gallbladder or perforated duodenal ulcer Appearance & Interpretation
Diagnosis: established with a combination of a physical examination & an imaging test (USG). Approx 1500 mL of fluid had to be present for flank dullness to be detected Lesser degrees of ascites can be missed. Ultrasonography can be helpful when the physical examination is not definitive Ascites
Ascites can be classified based on the underlying pathophysiology : Portal hypertension Cirrhosis, Alcoholic hepatitis Acute liver Hepatic veno-occlusive disease Heart failure Constrictive pericarditis Hemodialysis -associated ascites ( nephrogenic ascites ) Causes of Ascites
Other etiologies Chylous ascites Pancreatic ascites (disrupted pancreatic duct) Myxedema Causes of Ascites
Causes of Ascites
Routine tests Cell count and differential Albumin concentration Total protein concentration Culture in blood culture bottles Tests performed on ascitic fluid
The cell count with differential is the single most helpful test performed on ascitic fluid to evaluate for infection. Polymorphonuclear count ≥ 250/mm3 spontaneous bacterial peritonitis. In bloody ascites : one neutrophil should be subtracted from the absolute neutrophil count for every 250 red cells to yield the "corrected neutrophil count“. Cell count & differential count
The serum-to- ascites albumin gradient (SAAG ) accurately identifies the presence of portal hypertension and is more useful than the protein based exudate / transudate concept. SAAG Serum albumin value - ascitic fluid albumin ( obtained on the same day). SAAG ≥ 1.1 g/dL (11 g/L) Indicates portal hypertension ( Budd- Chiari syndrome, heart failure, or liver cirrhosis) SAAG <1.1 g/dL (<11 g/L) Indicates that the patient does not have portal hypertension Serum-to-Ascites Albumin gradient (SAAG)
Protein — Ascitic fluid had been classified as an exudate if the total protein concentration is ≥2.5 or 3 g/dL and A transudate if it is below this cut-off. However , the exudate / transudate system of ascitic fluid classification has been replaced by the SAAG. Measurement of total protein, glucose, and lactate dehydrogenase ( LDH) in ascites may also be of value in distinguishing SBP from gut perforation into ascites Protein, Glucose & LDH
Patients with ascitic fluid that has a neutrophil count ≥250 cells/mm3 and meets two out of the following three criteria are unlikely to have SBP and warrant immediate evaluation to determine if gut perforation into ascites has occurred. Total protein >1 g/dL Glucose <50 mg/dL (2.8 mmol/L) LDH greater than the upper limit of normal for serum. Bilirubin concentration should be measured in patients with brown ascites
Condition Glucose Uncomplicated cirrhotic ascites Similar to serum glucose Peritoneal carcinoma Low Gut perforation May be undetectable Glucose, LDH & Amylase Condition LDH Ascitic fluid/Serum (AF/S ratio) Uncomplicated cirrhotic Ascites 0.4 Infection or tumor More than 1.0 Condition Ascitic Amylase AF/S ratio of amylase Uncomplicated cirrhotic ascites 40 IU/L 0.4 pancreatitis or gut perforation ↑ ↑ Pancreatic ascites ↑↑↑ (2000 IU/L) ↑↑↑ ( 6.0)
Adenosine deaminase Adenosine deaminase activity of ascitic fluid has been proposed as a useful non-culture method of detecting tuberculous peritonitis ; however, patients with cirrhosis and tuberculous peritonitis usually have falsely low values . Adenosine deaminase (ADA)