There are certain enzymes that are useful in the process of dephosphorylation or the removal of the phosphate groups that are present in various molecules like proteins, nucleotides and alkaloids. Alkaline phosphatase is one of such hydrolase enzymes that is crucial for the process of phosphate removal. Alkaline phosphatase is also known as basic phosphatase, since it is mostly effective in an alkaline or basic environment (pH levels around 8). Alkaline phosphatase is mainly present in the liver, bile duct, placenta, bones and kidneys. In fact, normal alkaline phosphatase levels are extremely crucial for the healthy functioning of the liver. Alkaline phosphatase levels do rise to an extent during pregnancy. However, extremely high levels of alkaline phosphatase in pregnancy, could be an indication of some major health condition or problems related to the liver and other such body organs of a pregnant woman. Continue reading ahead, to find out more about the increased levels in alkaline phosphatase and its possible causes.
Normal Alkaline Phosphatase Levels in Pregnancy
Both high and low alkaline phosphatase levels could be an indication of some major disturbance in the proper functioning of certain body organs. Hence, one should learn about the importance of normal alkaline phosphatase levels. There are three basic types of alkaline phosphatase isozymes that are found in the human body. They include, ALPI (intestinal alkaline phosphatase), ALPL (alkaline phosphatase present in the liver, kidneys and bones), and ALPP (alkaline phosphatase present in the placenta). ALPP is also called Regan isozyme. In order to learn about any increase or decrease in the levels of alkaline phosphatase, one should learn about the normal range of alkaline phosphatase. In humans, 20 to 140 IU/L is considered to be the normal range of alkaline phosphatase.
However, it is important to understand that these levels are slightly on the higher side in children and pregnant women. Amongst pregnant women, a slight elevation in alkaline phosphatase can be noted during early pregnancy. Alkaline phosphatase levels reach to the peak during the 10th week of pregnancy. The alkaline phosphatase levels during this phase are around 50 to 75 IU/L. When the normal pregnancy alkaline phosphatase levels are elevated even further, it is a possible sign of some serious health condition. This elevation is almost three times greater than that of non-pregnant women. The normal elevated alkaline phosphatase levels during pregnancy are around 125 - 250 IU/L. In such situations, along with alkaline phosphatase, increase in other components like calcium and phosphorus may also be observed.
High Alkaline Phosphatase Levels in Pregnancy
When alkaline phosphatase levels get higher than the reference range, it can be associated with various health conditions. Blood tests and electrophoresis of isozymes are the basic determination methods that are performed for exact diagnosis of this condition during pregnancy.
- Liver Conditions: Certain liver diseases like cholecystitis, hepatitis A, hepatitis B, cholestasis, cholangitis, cirrhosis, fatty liver disease, liver cancer, sarcoidosis; drug intoxication and interactions with various drugs like ranitidine, erythromycin, carbamazepine, verapamil, allopurinol, phenytoin, HELLP syndrome (hemolysis-elevated liver enzymes), pre-eclampsia, etc. can lead to elevated alkaline phosphatase levels. Liver metastases which is caused by elevated gamma-glutamyl transpeptidase (GGT) also causes high alkaline phosphatase levels.
- Bone Conditions: Certain bone diseases like osteosarcoma, Paget's disease, metastatic bone cancer, fractured bone, renal osteodystrophy, multiple myeloma, rickets, osteomalacia, malignant tumors, hyperparathyroidism, hypothyroidism, several types of renal diseases, weak bones due to deficiency of vitamin D and/or calcium may also cause high alkaline phosphatase levels during pregnancy.
- Other Conditions: Apart from those mentioned above, erythremia, certain types of infections, myeloid metaplasia (myelofibrosis), intrahepatic cholelithiasis of pregnancy, etc., are also some of the possible reasons for such elevated levels. Elevated ALP levels can also be seen in a rare placental disease called chronic histiocytic intervillositis that causes miscarriage and stillbirth.
(Disclaimer: The information provided in this article is for educational purposes only. Always consult the concerned health care provider, for proper diagnosis and treatment of the specific health condition.)