Inherited Elevation of Alkaline Phosphatase Activity in the Absence of Disease

SERUM alkaline phosphatase activity was markedly elevated in a young man without an apparent underlying disorder. The unexpected finding of an elevated alkaline phosphatase level in the patient's father prompted an investigation of other family members.Subjects and MethodsA 15-year-old boy, 160 cm tall and weighing 41 kg, complained of abdominal pain. The results of physical examination and laboratory studies, including complete blood count, urinalysis and analysis of blood components, were normal, except for a serum alkaline phosphatase level greater than 1050 units per liter (normal, 30 to 85) (Bessey-Lowry-Brock method1).Subsequent evaluation revealed normal values for liver . . .