Laboratory Medicine Updates - November 4, 2004

University of Virginia Health System

Medical Laboratories

“Quality You Expect, Service You Deserve”

 

LABORATORY MEDICINE UPDATE

 

November 4, 2004

New Flow Cytometry Panels

Three new panels have been created to more accurately reflect our testing by flow cytometry.  The current test request form is in the process of being updated; you will be given new forms when available.  In the meantime, we solicit your help in notifying staff in your clinic as to the changes below.  If you write the panel name on the form we will proceed with performing the appropriate tests.  If you select the generic “B/T Cell Subsets* (Flow)” we will contact you for clarification.  Requests for flow cytometry for leukemia / lymphoma are made using the Consult test request form and require a history in order to select the proper markers (this process has not changed).

TBNK Panel:  this panel contains CD19, CD16+56, CD3, CD3+4, CD3+8, CD4:CD8 and CD4 absolute number

THS Panel:  this panel contains CD3, CD3+4, CD3+8, CD4:CD8 and CD4 absolute number

PNHSCR Panel:  this panel contains CD45, CD55 and CD59 for paroxysmal nocturnal hemoglobinuria

Change in Gold-Top Tubes

The Medical Laboratories have been notified by the vendor of the blood collection tubes (BD) of an artifactual positive bias when gold-top SST tubes are used in the analysis of Total T3, Total T4, folate, and Vitamin B12 and a negative bias in the analysis of FSH.  The vendor has resolved the problem and will be providing new tubes as soon as possible.  These new tubes will be distributed to all locations when they arrive; a letter outlining the specifics in more detail will be distributed to all members of the clinical staff at that time.

Hemoglobin Electrophoresis

When interpreting hemoglobin electrophoresis it is beneficial to have a current CBC.  This information is used to assist in the identification of abnormal hemoglobins and to determine the meaning of unusual quantities of hemoglobin that can be encountered.  Please order a CBC when requesting hemoglobin electrophoresis.


B-cell and T-cell Clonality by PCR and Capillary Electrophoresis

 

Lymphoid neoplasms are clonal proliferations of B-cells or T-cells and detection of a predominant B-cell or T-cell clone in a specimen that exhibits an atypical lymphoid infiltrate supports the diagnosis of lymphoma or leukemia.  The immunoglobulin heavy chain (IGH) and T-cell receptor gamma chain (TCR) genes represent unique cell-specific molecular targets for the PCR detection of B-cell and T-cell clonal proliferations, respectively.  Implementation of clonal analysis in the Molecular Diagnostics laboratory provides an additional tool in the work-up of lymphoma/leukemia.  The results of this test should be considered in conjunction with clinical information and/or additional diagnostics tests; the results are not intended to provide definitive diagnostic information.

 

The Molecular Diagnostics Laboratory has optimized and validated a method for lymphocyte clonality assessment that relies on capillary electrophoresis and commercially available primers.  InVivoScribe Technologies provides a comprehensive standardized set of multiplex PCR primer master mixes that have been validated in a large study (BIOMED-2 Concerted Action) conducted at more than 30 independent testing centers and using more than 400 clinical samples (Leukemia.  2003 Dec:17 (12):2257-2317).  The Molecular Diagnostics Laboratory has further validated the technology using a variety of tissues representing a spectrum of lymphoid malignancies and benign lymphoid proliferations.

 

Suitable specimen types include formalin-fixed/paraffin-embedded (FFPE) tissues, fresh frozen tissues, decalcified FFPE tissues, whole blood and bone marrow aspirates and CSF fluid.  In both the published work and the internal validation, the assay was shown to detect a clonal lymphoid proliferation from FFPE specimens in 92% of B-cell lymphomas and 85% of T-cell lymphomas.  The lowest limits of detection, under ideal circumstances, are less than a 2% clonal population in a polyclonal lymphocyte background.

 

IGH-PCR and TCR-PCR will be performed once per week; the charge for B-cell testing is $623 and for T-cell testing is $419.  Questions on this procedure may be directed to Dr. Mani Mahadevan (3-4816, msm8r@virginia.edu ), Dr. Larry Silverman (3-2957, lms7r@virginia.edu ),   Dr. Dede Haverstick (4-9202, dmh2t@virginia.edu ),  Dr. David Bruns (4-9432, deb6j@virginia.edu ), or Dr. Grant Bullock (4-9084; gcb2r@virginia.edu ).

 

Epidemiology Laboratory Relocation

The Epidemiology Laboratory, formerly a part of the Department of Medicine, has been integrated into the Medical Laboratories’ Microbiology section.  The new location is on the 3rd floor of the Old Medical School building.  The direct phone number for this laboratory remains the same.  For questions or assistance, please call Medical Laboratories’ customer service at 924-5227 (924-LABS).

 

 


Laboratory Relocation Update

 

Construction of the new building that will house the relocated Core, Microbiology and Molecular Diagnostics Laboratories continues, with completion expected in February 2005.     Lab Managers have reviewed and approved final designs for their respective space and have begun planning to ensure no disruption to stat and routine testing when the move occurs.

 

Groups are also working to address staff parking and security, telecommunication/IS requirements, and environmental and safety concerns.  The new lab building will be connected to the main hospital through an “Express” pneumatic tube system to ensure specimens can be transported back and forth without delay.

 

For additional information or questions regarding the upcoming relocation, please contact Cavell Kopetzky in Medical Laboratories Administration at 434-243-2649 (email: cak3w@virginia.edu ).