Sir.—Factitious hyponatremia is observed mainly in adults with hyperproteinemia or hyperlipidemia, but it is very rare in children.1
It was described in children who had uncontrolled diabetes mellitus with hyperglycemia and hyperlipidemia, as well as in patients with nephrotic syndrome and hyperlipidemia.2 The large amounts of macromolecules (lipid and/or protein) reduce the percentage of water contained in a unit volume of serum. A factitiously low value of the plasma sodium concentration will be reported, even though the sodium concentration in plasma is normal.
We have cared for a patient who manifested factitious hyponatremia due to hyperproteinemia, which is very rare in children. The patient, a 10-year-old girl, was diagnosed a year before admission as suffering from juvenile arthritis. Later on she manifested non-A, non-B hepatitis and was admitted to our department because of fever and respiratory distress. She had massive lobar pneumonia with pleural effusion. Her