Increased Skeletal Uptake of Tc-99m Methylene Diphosphonate in Milk-alkali Syndrome

A case of milk-alkali syndrome is described in a 34-year-old man taking an over-the-counter antacid preparation for gastroesophageal reflux. A Tc-99m MDP bone scan performed in the initial investigation of the hypercalcemia was markedly abnormal with a "metabolic" pattern of tracer uptake similar to that seen in hyperparathyroidism and humoral hypercalcemia. Following withdrawal of the antacid and calcium, the bone scan appearance returned to normal, as did the biochemical markers of his disease.