PNH by Flow Cytometry
General Information
- Lab Name
- PNH by Flow Cytometry
- Lab Code
- PNHFLO
- Epic Ordering
- PNH by Flow Cytometry
- Description
NOTICE:
The University of Washington Hematopathology laboratory is currently receiving requests for flow cytometry testing that exceed our capacity. We anticipate that turnaround times will be delayed in a subset of MRD flow cytometry cases, and we will no longer be able to regularly provide STAT call backs for MRD flow cases. Additionally, UW Hematopathology is unable to accept flow cytometry reference testing from new clients and will be limiting service to a subset of current clients.
In Paroxysmal Nocturnal Hemoglobinuria (PNH), a clonal marrow stem cell population gives rise to circulating mature hematopoietic cells lacking the expression of a variety of different cell surface proteins whose common feature is their linkage to the cell membrane via a glycosyl-phosphatidyl-inositol (GPI) linkage, a linkage that is deficient in the PNH clone. Similar findings may also be seen in aplastic anemia and myelodysplasia, although the frequency of GPI-deficient cells is lower. GPI-deficiency is most easily assessed in the erythroid, granulocytic and monocytic lineages, and flow cytometry is the method of choice for their detection. The flow cytometric assay evaluates for a loss of expression of the following GPI-linked antigens: CD59 on red cells, CD14 and FLAER on monocytes, and CD24 and FLAER on granulocytes. The assay can detect as little as 0.01% GPI-deficient cells in each cell lineage.
- References
Borowitz et al (2010) Guidelines for the diagnosis and monitoring of paroxysmal nocturnal hemoglobinuria and related disorders by flow cytometry. Cytometry Part B 78B:211 to 230.
- Forms & Requisitions
- Synonyms
- CD59, GPI deficient, Paroxysmal Nocturnal Hemoglobin
- Components
-
Code Name PNHSTA PNH by Flow Cytometry Status PNHSPD PNH by Flow Cytometry Spec Descr PNHHP PNH Case Number PNHRES PNH by Flow Cytometry Result PNHINT PNH by Flow Cytometry Interp PNHREV PNH by Flow Cytometry Results Reviewed by: PNHMET PNH by Flow Cytometry Method
Interpretation
- Method
Flow Cytometry
- Reference Range
- See individual components
- Interferences and Limitations
The assay is performed by flow cytometric immunophenotyping and interpreted by a trained hematopathologist. The assay has been validated for the diagnosis and monitoring of patients with hematopoietic neoplasms.
- References
Borowitz et al (2010) Guidelines for the diagnosis and monitoring of paroxysmal nocturnal hemoglobinuria and related disorders by flow cytometry. Cytometry Part B 78B:211 to 230.
- Guidelines
Ordering & Collection
- Specimen Type
- Peripheral Blood
- Collection
-
Blood: 6 mL blood in LAVENDER top (EDTA) tube
Unacceptable: Bone Marrow, Formalin fixed, paraffin embedded specimens
Please note: Green top tubes are accepted for testing.
- Forms & Requisitions
- Handling Instructions
Samples should be ambient and delivered to the laboratory without delay. Optimal results are achieved when samples are received within: 24-48 hours of collection
Samples submitted outside of this range will be evaluated for quality using appropriate internal controls and the results qualified appropriately.
- Quantity
-
requested: 6 mL blood
Processing
- Processing
Performance
- LIS Dept Code
- Hematopathology (HP)
- Performing Location(s)
-
Other Hematopathology
206-606-7060UW Hematopathology Laboratory, G7-800
Fred Hutchinson Cancer Center
825 Eastlake Avenue E.
Seattle, WA 98109Hematopathology hours:
5:30 am - 6:30 pm Monday through Saturday
7:30 am - 4:00 pm Sunday, and with reduced staffing on major holidays - Frequency
- Daily
- Available STAT?
- No
Billing & Coding
- CPT codes
- 88184, 88185x8, 88188
- LOINC
- 55164-8
- Interfaced Order Code
- UOW3462