Serum and ultradiafiltrate middle molecules in hemodialysed patients.

The gel filtration technique was used for the fractionation of middle molecular substances (MMS) in plasma from conservatively treated patients, from dialysed patients with renal failure and in the ultradiafiltrate from dialysed ones. The following observations were made: 1. MMS accumulate in the plasma of conservatively treated patients in chronic renal failure. 2. The accumulation of MMS in dialysed patients is even higher. 3. The elimination of the most important MMS in the ultradiafiltrate is excellent. 4. It is concluded that hemofiltration and ultradiafiltration are indicated also for the removal of MMS, namely in the case of clinical complications which cause a further accumulation of MMS.