Fluid removal systems and methods for removing fluid from a tissue site are presented. The system includes a semi-permeable inbound conduit, which is fluidly coupled to a treatment-fluid delivery unit, for placement proximate to a tissue site, and a semi-permeable outbound conduit, which is fluidly coupled to the inbound conduit and to a treatment-fluid collector, for placement proximate to the tissue site on the patient. The treatment-fluid collector receives the treatment fluid and a recruited fluid from the tissue site. A recruited-fluid determination unit may be coupled to the treatment-fluid collector to determine a volume of fluid recruited from the patient. The treatment fluid is any fluid (including a gas) that pulls fluid from the interstitial and intracellular space. A reduced-pressure treatment subsystem may also be included, among other things, for removing ascites and other fluids from a body cavity.