Gamma-glutamyl transferase (GGT) is an enzyme found in the liver, bile ducts, and pancreas. The GGT blood test measures the level of this enzyme in the blood, helping assess liver health. Elevated GGT levels can indicate liver damage or bile duct issues, often linked to conditions such as alcoholic liver disease, hepatitis, or bile duct obstruction. While GGT alone cannot diagnose specific liver conditions, it plays a vital role in liver function panels, particularly when combined with other liver enzymes like ALT and AST.

The calprotectin stool test is used to detect gut inflammation by measuring calprotectin levels, a protein released by white blood cells during inflammation. It is commonly used to diagnose inflammatory bowel disease (IBD) like Crohn’s disease and ulcerative colitis, distinguishing them from irritable bowel syndrome (IBS), which doesn't cause inflammation. Elevated calprotectin levels indicate active inflammation in the intestines, guiding doctors in diagnosing and monitoring treatment response for IBD patients. A normal result usually rules out significant gut inflammation.

Serum osmolality measures the concentration of solutes, like sodium, glucose, and urea, in your blood. It is essential for assessing your body’s fluid balance and electrolyte levels, helping to diagnose conditions such as dehydration, kidney issues, or imbalances in salt or sugar levels. Abnormal serum osmolality levels can indicate dehydration, overhydration, or metabolic disturbances, which may require treatment. Maintaining proper osmolality is critical for normal cellular function, as it helps regulate the movement of water between the body’s compartments.

Both the C-Reactive Protein (CRP) test and the Erythrocyte Sedimentation Rate (ESR) test measure inflammation, but they serve different purposes. CRP detects acute inflammation and provides more immediate results, often used in infections and inflammatory diseases. ESR, on the other hand, measures the rate at which red blood cells settle and is better at identifying chronic inflammation. While CRP is more specific and rises quickly in response to inflammation, ESR changes more slowly and is influenced by other factors like age and anemia. Doctors often use these tests together for a more comprehensive assessment.