ALT (SGPT) blood test explained

The modern name is alanine aminotransferase, abbreviated ALT. Some laboratories and clinicians still use SGPT. The test is commonly included with other liver-related blood tests, and its result is interpreted against the reference range printed by the laboratory.

A raised ALT indicates leakage of the enzyme from cells, usually liver cells, but does not reveal the diagnosis. Fatty liver change, viral infections, alcohol, medicines and supplements are among the possibilities a clinician may consider. The result can also fluctuate during a temporary illness.

ALT is reviewed with AST, bilirubin, alkaline phosphatase, albumin and the clinical picture. Different combinations point toward different types of liver or bile-duct problems. A normal ALT does not answer every question about liver health, and a high ALT does not by itself show how well the liver is performing its functions.

Discuss the report with the requesting clinician, including any earlier ALT results. Provide the names and doses of prescribed drugs, over-the-counter products, herbal preparations and fitness supplements. Mention recent infections, changes in weight, alcohol use and any family history of liver problems.

Depending on the degree and pattern of abnormality, the clinician may repeat the test, order tests for infections or metabolic causes, or arrange an ultrasound. Avoid starting a liver detox product while waiting; some herbal ingredients can themselves affect the liver. Do not discontinue prescribed medicine without specific advice.

Contact a medical service promptly if you develop yellowing of the eyes or skin, dark urine, pale bowel motions, continuing vomiting, increasing upper abdominal pain or pronounced weakness. Emergency assessment is appropriate for confusion, difficulty staying awake, significant bleeding or a rapidly enlarging abdomen.

Ask how your ALT compares with the laboratory range, whether the other liver tests form a recognizable pattern, and whether a repeat sample needs special preparation. Confirm whether any current product could affect the liver and what symptoms should bring your review forward.