Pyruvate kinase activity in red blood cells (PK RBC)

Why Is This Test Done?

Your doctor may order a pyruvate kinase RBC test if you have symptoms like fatigue, anemia, or jaundice, or if you have a family history of hereditary spherocytosis or other red blood cell disorders. It helps diagnose conditions where red blood cells break down prematurely or don’t function properly.

What to Expect Before the Test

No special preparation is needed. A blood sample will be drawn from a vein, usually in your arm. You may feel slight discomfort, but it’s a quick procedure. If you’re taking blood thinners, let your doctor know.

What the Results Mean

Results are compared to a baseline or reference range for your age and health. Very low levels of pyruvate kinase activity may suggest hereditary pyruvate kinase deficiency, a genetic disorder that can cause chronic anemia. Your doctor will discuss findings in the context of your symptoms and medical history.

Common Causes of Abnormal Results

Low pyruvate kinase activity is most commonly linked to hereditary pyruvate kinase deficiency, a rare genetic disorder. Other conditions that might be associated (less commonly) include certain types of anemia or red blood cell disorders.