Threonine, Cerebrospinal Fluid, Mass Concentration

What This Test Measures

Threonine is one of the building blocks of protein (an amino acid) that the body uses to make proteins and other important molecules. This test determines how much threonine is present in a sample of cerebrospinal fluid, which is collected through a procedure called a lumbar puncture (spinal tap).

Why Doctors Order It

Your healthcare provider may order this test when evaluating suspected amino acid metabolism disorders, unusual neurological symptoms, or nutritional concerns. It is often part of a broader panel of amino acid testing rather than a stand-alone test, and results are interpreted alongside other findings.

How the Sample Is Collected

Cerebrospinal fluid is collected by a clinician during a lumbar puncture, where a thin needle is placed in the lower back to draw a small sample of fluid. The sample is then sent to a laboratory for analysis. Your care team will explain any preparation steps beforehand.

What Results Mean

Results are reported as a mass concentration of threonine in the fluid. Whether a value is considered normal depends on the laboratory's own reference range and on the individual's age and clinical context. Your provider will interpret the result in light of your symptoms and other test results, so discuss any questions directly with them.