DIGITALIS-LIKEIMMUNOREACTIVE SUBSTANCE (DLIS) : A NEW HORIZON IN DETERMINING THE DRY WEIGHT ?

Perfect assessment of dry weight in hemodialysis patients has a vital importance. Intravascular hypervolemia increases the levels of digitalis-like immunoreactive substance (DLIS) and atrial natriuretic peptide (ANP). Since endogenous DLIS gives crossreaction to anti-digoxin antibodies, the levels of DLIS were determined by two seperate techniques, FPIA (fluorescence polarization enzyme immunoassay) and MEIA (microparticle enzyme immunoassay). The basal levels of DLIS-FPIA,DLIS-MEIA and ANP in forty-two hemodialysis patients were significantly higher compared to control (n:20) (p<0.05). The strong positive correlation between DLIS-FPIA andDLIS-MEIA (r:0.894, p<0.001) made us think that these two markers could be used interchangeably. Compared to the corresponding parameters of forty-two hemodialysis patients, DLIS and ANP levels of eleven patients, selected as hypervolemic by conventional criteriae, were higher. After three months of ultrafiltration treatment, we determined that the levels of DLIS and ANP decreased significantly approaching control levels. We concluded that the tests of DLIS and ANP were useful to assess dry weight and to determine the intravascular volume response to ultrafiltration treatment.