1. Therapeutic—to reduce intra-abdominal pressure in patients with massive ascites causing cardiorespiratory compromise.

2. Diagnostic—to aid in determining the etiology of neonatal ascites and/or peritonitis.

a. Necrotizing enterocolitis with suspicion of gangrene or perforation: presence of fecal matter or bacteria and white blood cells on a smear (1, 2, 3)

b. Hepatic ascites: comparison of serum and ascitic albumin levels, cell count, and culture in diagnosis of spontaneous bacterial peritonitis (4, 5)

c. Chylous ascites: testing for triglycerides, cholesterol, and lymphocytes on cell count of the fluid (3, 6)

d. Urinary ascites: test for creatinine content (7)

e. Meconium peritonitis: gross appearance of ascites (8)

f. Biliary ascites: test for bilirubin level (9)

g. Pancreatic ascites: test for amylase, lipase levels (5, 10)

h. Congenital infections—cytomegalovirus (CMV), tuberculosis, toxoplasmosis, syphilis: test for inclusion bodies, treponemes (5, 11)

i. Inborn errors of metabolism—sialic acid storage disorders: test for vacuolated lymphocytes and free sialic acid (12)