, dialysis disequilibrium syndrome
, commonly abbreviated DDS
, is the occurrence of neurologic signs
, attributed to cerebral edema
, during or following shortly after intermittent hemodialysis
Classically, DDS arises in individuals starting hemodialysis due to chronic renal failure and is associated, in particular, with "aggressive" (high solute removal) dialysis. However, it may also arise in fast onset, i.e. acute, renal failure in certain conditions.
The cause of DDS is currently not well understood.
There are two theories to explain it; the first theory postulates that urea transport from the brain cells is slowed in chronic renal failure, leading to a large urea concentration gradient, which resulting in reverse osmosis. The second theory postulates that organic compounds are increased in uremia to protect the brain and result in injury by, like in the first theory, reverse osmosis.
of cerebral edema, such as focal neurological deficits
and decreased level of consciousness
, if temporally associated with recent hemodialysis, suggest the diagnosis. A computed tomography
of the head is typically done to rule-out other intracranial causes.
MRI of the head has been used in research to better understand DDS.
Avoidance is the primary treatment.
DDS is a reason why hemodialysis initiation is usually done gradually, i.e. it is a reason the first few dialysis sessions are shorter than is typical in an end-stage renal disease