Category: Gastroenterology & Hepatology
Test Code: 166
Disease: Autoimmune Liver Diseases
Methodology: ELISA
Reference Range: Negative: <20 ; Borderline: 20-24.9 ; Positive: ≥25
CPT Code: 83516
Schedule / Turnaround Time: Assay performed once every two weeks. Report availability is two weeks from the time of specimen receipt.
Specimen Requirements:

Specimen need not be refrigerated or frozen. Collect 2-3 ml of blood in a red top or serum separator tube. If possible, separate serum from clot and place into white tube provided with Immco Diagnostics’ collection kits. If separation facilities are not available, the blood can be sent in the tube used for collection.

Sample Stability:

Sample is stable at ambient temperature during shipment. If sample is stored prior to shipment, it is stable refrigerated (2-8˚C) up to five days and frozen (-20˚C or lower) up to one year.


SP100 antibodies have been found in approximately 25% of primary biliary cirrhosis (PBC) patients and are highly specific for PBC. In addition, SP100 antibodies are found in some patients who test negative for conventional markers of PBC such as mitochondrial antibody (AMA) and mitochondrial M2 antibody (M2). The presence of SP100 antibodies can add to the strength of diagnosis of PBC in cases where the clinical presentation and/or serological picture may be unclear.