What does the Ceruloplasmin test measure?

Why is Ceruloplasmin measured?

Serum ceruloplasmin is measured primarily to screen for and monitor Wilson disease, an autosomal-recessive disorder of hepatic copper export in which ceruloplasmin is characteristically low and unbound 'free' copper accumulates. Low ceruloplasmin also occurs in copper deficiency, severe protein loss (nephrotic syndrome, protein-losing enteropathy), and aceruloplasminaemia (a rare hereditary disorder of iron overload). Conversely, because ceruloplasmin is an acute-phase protein, it is elevated in inflammation, pregnancy, and oestrogen therapy, which can normalise values in Wilson disease and complicate interpretation. Ceruloplasmin should not be used in isolation to diagnose Wilson disease; it is one component of a diagnostic algorithm that includes serum copper, 24-hour urinary copper, slit-lamp examination for Kayser-Fleischer rings, and often genetic testing.

Reference ranges

Standard reference

Approximately 20–60 mg/dL in adults; age- and assay-specific.

Functional medicine optimal

No single optimal range is defined; interpretation depends on clinical context, age, and whether inflammation or oestrogen is present. Persistent values <20 mg/dL warrant Wilson disease evaluation.

Units

mg/dL, g/L, µmol/L

Reference ranges vary by laboratory and assay platform. Interpret in context of the issuing laboratory's stated range.