Laboratory Medicine Updates - April 20, 2006

University of Virginia Health System

Medical Laboratories

"Quality You Expect, Service You Deserve"

LABORATORY MEDICINE UPDATE

April 20, 2006

Microbiological Specimens in Blood Culture Bottles

Sterile body fluids, other than blood, sent to the Clinical Microbiology department should be submitted in a sterile container (black top tube or cup) rather than blood culture bottles.  This allows us to perform a gram stain and ensures quantification if an organism does grow.  If blood culture bottles are inoculated as well as a sterile black top tube, please make every effort to send them to the laboratory together so that a gram stain can be performed and any organisms that grow will be quantified.

When sending other liquid specimens such as drainage and abscess material, submit these in a sterile container. It is never appropriate to submit these specimens in blood culture bottles.

 

Urinalysis, reflex culture if indicated - Second Announcement

Beginning February 28, 2006, the Medical Laboratories began offering the following test menu for urines:

  1. Urinalysis - currently offered
  2. Urine Culture - currently offered
  3. Urinalysis, reflex culture if indicated - NEW OPTION

Options 1 and 2 are stand alone tests and may be ordered independently depending on the clinician's needs.

Option 3 (NEW OPTION) - A urinalysis will be performed. If any of the following criteria are met, a urine culture will be performed without further orders from the physician:

  • Positive Leukocyte Esterase
  • Positive Nitrite
  • >5 White Blood Cells/HPF
  • Any bacteria present

All options are available for ordering through MIS and CareCast.  Current outpatient test request forms do not have the new option on the form; requests for the new option should be written on the form as "Urinalysis reflex culture if indicated".  The next revision of this form will include a place to mark this option.


Change in acceptable specimen types for MRSA and VRE screens

Please note that only the following specimens are now accepted for MRSA and VRE screening:

For MRSA:                                                        For VRE:

Axilla                                                                 Perirectal

Groin

Nares

Perirectal

Throat

All the above specimens should be submitted on a CulturetteĀ®.  Any other specimen types will be cancelled and the ordering location or physician will be notified, as they are not appropriate for screening.

Samples obtained from other body sites that may be necessary to screen patients for colonization (e.g., wounds, urine, foreign body sites) must be ordered by the treating physician as a regular laboratory request through MIS or on an out-patient test request form.

 

 

Intact Parathyroid Hormone

Due to a nationwide reagent availability problem, the Medical Laboratory has changed PTH assay vendors. The new assay is diagnostically equivalent to the previous one in routine use. Patient results will appear about 50-60% higher in the new assay, corresponding to a new reference interval for serum specimens of 12 to 65 pg/mL.  This assay went into use on March 15, 2006.  There is no change in specimen type (serum) or availability. More information on assay performance details is available through the Clinical Chemistry Resident on-call (pic# 1267).

 

Sirolimus (RapamuneĀ®) testing available in-house

Beginning April 18, 2006, the Toxicology Laboratory began Sirolimus testing using the Abbott immunoassay methodology.  Testing is available 7 days a week with results available by 1500 if samples are received by the laboratory by 1100 that day.  Specimen type is whole blood (EDTA, purple top tube) with a minimum volume of 1 mL.  Values greater than 15 ng/mL will be considered toxic and will be called to the ordering physician.

 

COMING SOON!  Another Laboratory Move

The Blood Bank at the Medical Center Main Hospital will be moving its entire operations from location 2621 to location 2801, (same floor) on May 4th at 1300.  There is no planned interruption of any service.  All phone numbers and tube numbers will remain the same.  Signs and directions will be forthcoming as the date approaches.

 

Changes to lab results screens in CareCast

To meet Federal regulations, all laboratory test results must be identified with the performing laboratory.  In CareCast, a statement has been added to all laboratory results screens: "UVAML unless noted" to indicate that any results were performed by University of Virginia Medical Laboratories, Charlottesville, VA (UVAML) unless otherwise indicated by a statement such as "Performed by Mayo Medical Laboratories, Rochester, MN."

 

 

Prenatal screening results (Quad testing) available electronically

Beginning April 18, 2006, results for second trimester prenatal screening are available as part of the electronic medical record.  As CareCast is implemented in the outpatient clinics, the test (with appropriate demographic information) will be able to be ordered electronically as well.

 

 

Transport of samples with known high white cell counts

Concerns have been raised about pneumatic tube transport of specimens with known high WBC counts, particularly when the white cells are "fragile" as in hematologic malignancies.  The effect of possible leakage of constituents (particularly potassium, phosphorus and LDH) from the cells during transport causing high results is quite variable among patients.  The Chemistry Division of the laboratory recommends one of the following:

  • o Centrifugation of the specimen before transport
  • o Hand carry the sample to the Clinical Laboratory Building
  • o For inpatients, whole blood analysis for potassium may be performed on a blood gas analyzer located in the ICU's