chylous ascites
Chylous ascites (also known as chyloperitoneum) is defined as the abnormal intraperitoneal accumulation of milky lymphatic fluid with a triglyceride level >110 mg/dL . Etiologically it is due to a disruption of the lymphatic system, most commonly obstructive due to a mass or traumatic (which maybe iatrogenic).
Clinical presentation
- abdominal distension
- abdominal discomfort
- dyspnea: splinting of the diaphragm by ascites
- sequelae of hypoproteinemia: edema
- acute abdomen: acute chylous peritonitis
For fluid aspirated from the abdomen to be chyle, triglycerides need to be elevated above 110 mg/dL (two to eightfold more than normal plasma concentration) with a specific gravity >1.012.
Pathology
Etiology
The pathogenesis of chylous ascites relies upon a disruption to the normal lymphatic pathways :
- obstruction of the lymphatics: usually a mass e.g. malignancy
- fistula between the lymphatics and the peritoneum/mesentery: usually trauma or surgery
- leakage of retroperitoneal megalymphatics: usually congenital
Radiographic features
Large volume fluid in the peritoneal cavity is the normal finding. However, if the patient is allowed to remain supine for a short interval then the fat commonly rises to the top of the fluid (fat is less dense than water), producing a fat-fluid level (cf. chyluria), which is highly specific for chyloperitoneum.
CT
On CT, chylous ascites is indistinguishable from water on density measurements. Fat-fluid levels are common.
MRI
On MRI, due to its high fat content, chylous ascites often demonstrates distinctive signal drop out on fat saturated sequences.
History and etymology
Morton described a case of a boy dying from chylous ascites caused by tuberculosis in 1694, the first known appearance of this condition in the literature .
See also
- ascites
- hemoperitoneum
- pneumoperitoneum
- uroperitoneum
- chyluria
- chylothorax
Siehe auch:
Assoziationen und Differentialdiagnosen zu Chyloperitoneum:
