Editing Liver function tests (section)

===Alanine transaminase (ALT)===
{{Main|Alanine transaminase|Elevated transaminases}}
{| class="wikitable" align="right"
| Reference range
|-
| 7-56 IU/L<ref name="Shivaraj 2009"/>
|}
Apart from being found in high concentrations in the liver, ALT is found in the kidneys, heart, and muscles. It catalyses the [[transamination]] reaction, and only exists in a cytoplasmic form. Any kind of liver injury can cause a rise in ALT. A rise of up to 300 IU/L is not specific to the liver, but can be due to the damage of other organs such as the kidneys or muscles. When ALT rises to more than 500 IU/L, causes are usually from the liver. It can be due to hepatitis, ischemic liver injury, and toxins that causes liver damage. The ALT levels in [[hepatitis C]] rises more than in hepatitis A and B. Persistent ALT elevation more than 6 months is known as [[chronic hepatitis]]. [[Alcoholic liver disease]], [[non-alcoholic fatty liver disease]] (NAFLD), fat accumulation in liver during childhood obesity, [[steatohepatitis]] (inflammation of fatty liver disease) are associated with a rise in ALT. Rise in ALT is also associated with reduced insulin response, reduced glucose tolerance, and increased free [[fatty acid]]s and [[triglyceride]]s. Bright liver syndrome (bright liver on ultrasound suggestive of fatty liver) with raised ALT is suggestive of [[metabolic syndrome]].<ref name="Shivaraj 2009"/>

In pregnancy, ALT levels would rise during the second trimester. In one of the studies, measured ALT levels in pregnancy-related conditions such as [[hyperemesis gravidarum]] was 103.5 IU/L, [[pre-eclampsia]] was 115, [[HELLP syndrome]] was 149. ALT levels would reduce by greater than 50% in three days after child delivery. Another study also shows that [[caffeine]] consumption can reduce the risk of ALT elevation in those who consume alcohol, overweight people, impaired glucose metabolism, and viral hepatitis.<ref name="Shivaraj 2009"/>