What are electrolytes and sodium? Electrolytes are “salts” in our blood and cellular fluids. The difference between the concentrations of these salts inside and outside the cells regulates the contraction of muscle cells and the signal transduction in brain cells (neurons). Sodium is the major salt outside the cells. The reference range for serum sodium is 135-145 mmol/L.
It seems like some patients with Wolfram syndrome experience “low sodium.” Our body regulates sodium levels by balancing water in the body with use of antidiuretic hormone. DDAVP is often prescribed for patients with Wolfram syndrome because they tend to produce less antidiuretic hormone and produce excess amount of urine. DDAVP is a synthetic antidiuretic hormone, regulates the body’s retention of water, and decreases the volume of urine. The challenge for Wolfram patients is that they tend to have bladder problems and may need to go to bathroom often. This is not because of the excess production of urine, but they may increase the dose of DDAVP, which increases the body’s retention of water and may lead to low sodium levels. As our colleague Dr. Marshall recommends, Wolfram patients should consult with their endocrinologists if they feel their serum sodium levels are low.
In addition, serum sodium levels may not be reliable when patients have poor renal functions or have severe hyperglycemia.