An unusual but pathognomonic appearance of chylous ascites was observe
d on computed tomographic (CT) and ultrasound examinations of the abdo
men in a patient with AIDS and disseminated tuberculosis. The images s
howed gradual development of fat-fluid level in the peritoneal collect
ion when the patient maintained a recumbent position. The explanation
for this phenomenon is provided together with a brief review of pertin
ent literature.