Support the diagnosis of autoimmune lymphoproliferative syndrome (ALPS).
Quantitative Flow Cytometry
Green (Sodium or Lithium Heparin), Lavender (EDTA), or Pink (K2EDTA)
Transport 5 mL whole blood. (Min: 0.5 mL)
CRITICAL ROOM TEMPERATURE
Clotted or hemolyzed specimens
Specimens must be analyzed within 48 hours of collection
Ambient: 48 hours; Refrigerated: Unacceptable; Frozen: Unacceptable
Reports include age appropriate reference intervals and interpretation.
|Test Number||Components||Age: 2-18 years old||Age 18-69 years old|
|Absolute alpha/beta TCR+ DNT||0-46 (cells/uL)||0-32 (cells/uL)|
|Absolute alpha/beta TCR+ DNT B220+||0-5 (cells/uL)||0-6 (cells/uL)|
|% alpha/beta TCR+ DNT||0-3 (%)||0-2 (%)|
|% alpha/beta TCR+ DNT B220+||0-0.3 (%)||0-0.4 (%)|
Reported percentages reflect percentage of CD3 positive lymphocytes. The hallmark for a diagnosis of Autoimmune Lymphoproliferative Syndrome (ALPS) is an increased concentration of CD3+ T-cells negative for CD4 and CD8 (double-negative T-cells [DNT]) and positive for the alpha/beta T-cell receptor (TCR). B220 expression on alpha/beta TCR+DNT cells is a sensitive and specific marker for ALPS and is associated with mutations in the FAS gene.
Abnormal results should be correlated with clinical history and confirmed by additional testing for defective in vitro lymphocyte apoptosis and for mutations in the FAS gene.
Laboratory Developed Test (LDT)
|Component Test Code*||Component Chart Name||LOINC|
|2014514||Absolute alpha/beta TCR+ DNT||34963-9|
|2014515||Absolute alpha/beta TCR+ DNT B220+||88053-4|
|2014516||% alpha/beta TCR+ DNT||34962-1|
|2014517||% alpha/beta TCR+ DNT B220+||88053-4|