Milk-alkali syndrome due to regular consumption of thermal water

The milk-alkali syndrome (MAS) is a triad of hypercalcemia, metabolic alkalosis, and renal failure, which is a consequence of high intake of calcium and absorbed alkaline salts. The syndrome presents with various onsets of hypercalcemia and, if untreated, may cause renal failure. An 83-year-old man was referred to our nephrology outpatient clinic because of persistently high serum calcium levels and renal insufficiency. Previous investigations could not evaluate the cause of hypercalcemia. Finally, it turned out that the patient had been drinking 1.5-2.0 l of thermal water daily with considerable calcium content for years. Cessation of thermal water consumption resulted in the normalization of all parameters and clinical signs, indicating that the cause of MAS in this case was an unusual factor, i.e., the consumption of excessive amounts of thermal water.