Pathology tests database

Sample and container requirements

Li heparin blood EDTA Whole blood

Minimum volume required

1 mL Li Heparin blood 1 ml EDTA whole blood

Special requirements

none

Patient preparation

None

Sample viability

EDTA sample <48 hours old Li Hep <25 hrs old

Turnaround time

up to 28 days

Reference range

Clinical guidance

Extended B cell immunophenotyping is used for assessment of immunodeficiency and immune competence in patients where B cell function (humoral immunity) is compromised.  It is currently used as a research tool, as it has not been diagnostically validated, but is informative in primary antibody immunodeficiency conditions such as common variable immunodeficiency (CVID), hyper-IgM syndromes (CD40L, CD40, AID, UNG and NEMO), and in XLP (SAP and XIAP); assessing B cell subset reconstitution after stem cell or bone marrow transplant and assessing response to B cell-depleting immunotherapy (eg Rituximab).  It may be informative in identifying defects in TACI and BAFF-R in patients presenting with clinical symptoms and other laboratory features consistent with CVID.  Notably, transitional cells are also increased in SLE and Sjogrens syndrome, and plasmablasts are increased in multiple myeloma.  Irreversible depletion of memory B cells is also described in HIV-1 infection.

Notes

This is a research assay only and not available for routine use.