Alanine Aminotransferase (ALT/SGPT)
| Alanine Aminotransferase (ALT/SGPT) | | | |
| Number | | 001545 |
| CPT | | 84460 |
| Synonyms | | ALT ; Glutamic Pyruvate Transaminase ; GPT ; SGPT ; Transaminases |
| Specimen | | Serum |
| Volume | | 1 mL |
| Minimum Volume | | 0.5 mL |
| Container | | Red-top tube or gel-barrier tube |
| Collection | | Separate serum from cells within 45 minutes of collection. |
| Storage Instructions | | Maintain specimen at room temperature. |
| Causes for Rejection | | Gross hemolysis; excessive lipemia; improper labeling |
| Use | | A liver function test, ALT is more sensitive for the detection of hepatocyte injury than for biliary obstruction. ALT is more specific for liver injury than AST (SGOT). Useful for hepatic cirrhosis, other liver disease. Increased in Reye syndrome, with AST.1 Test for hepatitis including non-A, non-B hepatitis. Acute hepatitis A or B can be confirmed serologically, as can hepatitis C. Negative serological findings in the presence of hepatitis-like chemistry abnormalities may also suggest acute drug-induced hepatitis, an impression supported by resolution after removal of the offending agent.2 The combination of increased AST and ALT with negative hepatitis markers occurs in a number of other entities including infectious mononucleosis. Sensitive to heart failure. ALT has been used in combination with anti-HBc as an indirect test for non-A, non-B, hepatitis in blood donors.3,4,5 |
| Limitations | | Grossly hemolyzed samples can generate somewhat spurious results. The activity in red cells is six times that of serum. Elevations are reported in trauma to striated muscle, rhabdomyolysis, polymyositis and dermatomyositis, but the CK (CK-MM fraction) is increased in such patients and it is preferable to consider diseases of skeletal muscle. ALT is less sensitive than is AST to alcoholic liver disease. Increased ALT is found with obesity. |
| Methodology | | Kinetic |
| Additional Information | | Among entities in which AST and ALT increases occur, are therapeutic applications of bovine or porcine heparin. LD (LDH) abnormality with elevation of hepatic fractions was also reported.6 In children with acute lymphoblastic leukemia, high ALT activity at diagnosis is associated with rapidly progressive ALL.7 A number of drugs, including diphenylhydantoin, heparin therapy and many others, cause ALT increases. Acetaminophen hepatotoxicity may be potentiated in alcoholics, in whom coagulopathy and extremely abnormal aminotransferase levels are described, ALT less than AST.8 The hepatitis C virion has been detected by polymerase chain reaction and reverse transcriptase of HCV-RNA sequences in patients with elevated ALT and positive anti-HCV.9 |
| Footnotes | | - “Diagnosis and Treatment of Reye's Syndrome,” JAMA, 1981, 246(21):2441-4.
- Frank BB and Members of the Patient Care Committee of the American Gastroenterological Association, “Clinical Evaluation of Jaundice - A Guideline of the Patient Care Committee of the American Gastroenterological Association,” JAMA, 1989, 262(21):3031-4.
- Biswas R, “Post-transfusion Non-A, Non-B Hepatitis: Significance of Raised ALT and Anti-HBc in Blood Donors” Vox Sang, 1989, 56(1):63.
- Friedman LS, Dienstag JL, Watkins E, et al, “Evaluation of Blood Donors With Elevated Serum Alanine Aminotransferase Levels,” Ann Intern Med, 1987, 107(2):137-44 (published erratum: Ann Intern Med, 1987, 107:791).
- Spurling CL and Saxena S, “Controversies in Transfusion Medicine. Alanine Aminotransferase Screening of Blood Donors,” Transfusion, 1990, 30(4):368-73.
- Dukes GE Jr, Sanders SW, Russo J Jr, et al, “Transaminase Elevations in Patients Receiving Bovine or Porcine Heparin,” Ann Intern Med, 1984, 100(5):646-50.
- Rautonen J, and Siimes MA, “Elevated Serum Transaminase Activity at Diagnosis Is Associated With Rapidly Progressing Disease in Children With Acute Lymphoblastic Leukemia,” Cancer, 1988, 61(4):754-7.
- Seeff LB, Cuccherini BA, Zimmerman HJ, et al, “Acetaminophen Hepatotoxicity in Alcoholics. A Therapeutic Misadventure,” Ann Intern Med, 1986, 104(3):399-404.
- Ulrich PP, Romeo JM, Lane PK, et al, “Detection, Semiquantitation, and Genetic Variation in Hepatitis C Virus Sequences Amplified From the Plasma of Blood Donors With Elevated Alanine Aminotransferase,” J Clin Invest, 1990, 86(5):1609-14
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