Hypernatremia From Water Softener Malfunction During Home Dialysis

To the Editor.— In many parts of the country, naturally occurring concentrations of calcium and magnesium necessitate pretreatment of water before dialysis. 1 The following case is presented to describe a serious hypernatremia during home hemodialysis resulting from malfunction of a water softener. Report of a Case.— A 44-year-old man with uremia due to chronic glomerulonephritis had been treated by home hemodialysis since March 1967, performed with disposable twin-coil dialyzers in a single-canister, 100-liter tank. Water for dialysis is processed by an automatically cycled cation exchange resin water softener. On April 3, 1970, after two hours of uneventful dialysis, just after a change of the dialysis bath, the patient suddenly felt flushed, developed severe pain in the neck and a headache, and complained of yellow vision. Following a period of profound thirst, he vomited and became combatitive and disoriented. Dialysis was discontinued approximately 10 to 15 minutes after the onset