Alkaline phosphatase is raised in all of the following except: September 2009
Ans. C: Prostatic tumorPossible causes of increased levels of plasma alkaline phosphatase include:Hepatobiliary disease including:- Cholestasis: increased synthesis of hepatocyte ALP and increased secretion of high molecular weight form intoplasma; elevations of ALP of up to 10 times normal levels- Hepatocyte disease, such as viral hepatitis which cause moderate elevations in ALPBone disease - bone isoenzyme of alkaline phosphatase, reflecting increased osteoblastic activity, may be raised in:- Paget's disease- Osteomalacia and rickets- Renal osteodystrophy- Bone metastases- Primary bone tumour e.g. sarcoma- Growing child- especially at pubeyDuring pregnancy the placenta secretes its own isoenzyme which raises total alkaline phosphatase concentrationMalignancies resulting in expression of ALP-like gene e.g. seminomasIn determining whether a raised ALP is of hepatic or bony origin e.g. in metastasis of breast cancer, the following may be useful:Other test of hepatic function e.g. GGTElectrophoresis separation of isoenzymesBone scanUltrasound scan of liver
Obstructive jaundice
Placental tumor
Prostatic tumor
Skeletal tumor