Alkaline phosphatase (ALP) is an enzyme produced primarily in the liver. The kidneys, intestine and bones also contribute in smaller amounts. As a clinical diagnostic tool, elevated alkaline phosphatate should be assessed along with other enzymes, but can indicate a number of medical conditions.
Liver Disease or Damage
An elevated alkaline phosphatase can be indicative of conditions such as gallstones, hepatitis, cirrhosis and liver cancer.
Bone diseases such as rickets, osteomalacia and Paget's disease cause elevated ALP levels, as do bone tumors or cancer. The enzyme level may also rise during the healing of a bone fracture, and in that instance would not be suggestive of malignancy.
Though not as common, if liver and bone disease are ruled out in the presence of an elevated ALP, other causes include heart attack or heart failure, kidney cancer, sepsis, hyperparathyroidism and mononucleosis.