Screening

Establish or confirm diagnosis

As a component to the initial evaluation of a patient presenting with hepatosplenomegaly. This test is not suitable for the identification of carriers. This test should not be used as a monitoring tool for patients with confirmed diagnoses.

An internal standard is added to an aliquot of plasma, which is then subjected to protein precipitation. Following centrifugation, the supernatant is subjected to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The MS/MS is operated in the multiple reaction monitoring positive mode to follow the precursor to product species transitions for … An internal standard is added to an aliquot of plasma, which is then subjected to protein precipitation. Following centrifugation, the supernatant is subjected to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The MS/MS is operated in the multiple reaction monitoring positive mode to follow the precursor to product species transitions for each analyte and internal standard. The ratio of the extracted peak areas to internal standard is determined by LC-MS/MS is used to calculate the concentration of in the sample.(Unpublished Mayo method) View more

Tests performed
Entire test performed in-house

Recovery was used to assess accuracy; mean recovery was 81%. Intra assay precision was performed at 3 levels: CV results ranged from 3%-19% (N=20 each). Inter assay precision was performed at 3 levels: CV results ranged from 3%-73% where higher CVs were obtained for physiologically low analyte concentrations near zero … Recovery was used to assess accuracy; mean recovery was 81%. Intra assay precision was performed at 3 levels: CV results ranged from 3%-19% (N=20 each). Inter assay precision was performed at 3 levels: CV results ranged from 3%-73% where higher CVs were obtained for physiologically low analyte concentrations near zero (N=20 each). The analytical measurement range varies per analyte but ranges from 0.001-1.00 µM View more

Patients with Wolman disease or cholestatic biliary atresia may have a profile similar to Niemann-Pick disease type C (NPC). Patients with bile acid malabsorption or ileal resection may have elevations of 7-alpha-hydroxy-4-cholesten-3-one (7aC4). This test does not identify all causes of hepatosplenomegaly. A positive test result is strongly suggestive of … Patients with Wolman disease or cholestatic biliary atresia may have a profile similar to Niemann-Pick disease type C (NPC). Patients with bile acid malabsorption or ileal resection may have elevations of 7-alpha-hydroxy-4-cholesten-3-one (7aC4). This test does not identify all causes of hepatosplenomegaly. A positive test result is strongly suggestive of a diagnosis but needs follow-up by stand-alone biochemical or molecular assay. View more

Is proficiency testing performed for this test? Help
Yes

Method used for proficiency testing: Help
Formal PT program

PT Provider: Help
European Research Network for the Evaluation and Improvement of Screening Diagnosis and Treatment of Inherited Metabolic Disorders - External Quality Assessment Schemes, ERNDIM EQAS

Description of PT method: Help
Formal PT program

Description of internal test validation method: Help
This test was laboratory developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements.