University of Virginia Health
Medical Laboratories
“Quality You Expect, Service You Deserve”
LABORATORY MEDICINE UPDATE
June 7, 2005
Core, Clinical Microbiology, and Molecular Diagnostics Laboratories Move
The Core, Microbiology, and Molecular Diagnostics Laboratories are scheduled to move into the newly constructed Main Street Laboratory facility over the weekend of June 11-12. Following the move, specimens sent to the Clinical Laboratories via pneumatic tube will automatically be re-routed to the new facility. Messenger delivery of specimens that cannot be transported by pneumatic tube will continue as before. Laboratory results will be reported electronically in the usual fashion. Telephone queries to the laboratories should still be directed to the 4-LABS (924-5227) telephone number. All phone and fax numbers will remain the same.
Every attempt has been made in planning this move to minimize disruptions to laboratory services. Assuming that the move proceeds as planned, it should be virtually invisible to users of laboratory services. In case of problems, chief residents on each clinical service will be contacted and contingency plans implemented.
Concurrent with this laboratory move, the Clinical Laboratories will begin using new instruments for chemistry/immunoassay testing. Methodologies for a few tests will give considerably different results than the current assays. These are presented below in separate, more-detailed paragraphs. Some of the new assays may have slightly different reference intervals from those currently in use. Changes to reference intervals are detailed in the Table below and will become effective on June 13 at
Major Reference Interval Changes
Please note the following:
Troponin – Troponin results reported by the new analyzer will be approximately half the concentrations of results currently being reported. However the new assay will be more sensitive (a lower limit of detection approximately equal to 0.01 ng/mL) and its results will be more precise in the lower concentration ranges (<0.10 ng/mL). The upper limit of the reference interval for the new assay (0.02 ng/mL) is the 99th percentile of the healthy population in line with recent recommendations of the
Ferritin – The new instrumentation provides significantly lower absolute values for Ferritin. The new reference intervals are Males: 20-250 ng/mL and Females: 10-120 ng/mL.
T-Uptake – The new analyzer measures the total binding capacity present in the sample rather than the %T3-Uptake. Thus, rather than reporting results as percent, the new test will report in “Units” representing T-Uptake Units. When this test is ordered with the Total T4, the Free Thyroxin Index (FTI) can be calculated using the following formula:
FTI = (Total T4)/T-Uptake Unit
Free T4 – The new instrumentation provides results that are approximately 25 percent lower than the current analyzer. As a result, the new reference interval will be 0.70 to 1.50 ng/dL (based on analysis of 411 controls patients with normal thyroid function).
Salicylate – With the new instrumentation, the reporting units for Salicylate will change from mg/dL to mg/L. This will result in numbers with an absolute value of one-tenth the previous (50 would become 5). Reference intervals will be appropriately modified in all computer systems and on patient reports
Percent Free PSA
The new chemistry instrumentation will allow the UVa Core Laboratory to offer testing for Free PSA as an in-house test. Ordering this test will result in an initial Total PSA determination. If the result is between 4 and 10 ng/mL, a Free PSA determination and a calculation for % Free PSA will be performed and reported. If the Total PSA is outside of this range, the request for Free PSA will be cancelled as current data suggest the diagnostic utility of this test is limited to this range.
PSA
Results by the new assay compare much more favorably with the Hybritech Tandem-R assay (upon which most of the currently used PSA screening limits are based)*. Thus the new results will be higher than the PSA results obtained with our current analyzer. Analysis of 64 patient samples in parallel on the two analyzers suggest that values from the Abbott analyzer will be approximately 1.3 times as high as the current analyzer due to differences in calibration between the two manufacturers.
The detection limit for the Architect total PSA assay is 0.05 µg/L compared to the current assay limit of 0.06 µg/L.
As with all markers of tumor recurrence, the current instrument will remain operational for a period of time following our move to allow re-baselining any prostatectomized patients. Requests for such duplicate testing (at no charge to the patient) should be made on the outpatient test request form.
*Sokoll, et al. Differences in Free PSA and Total PSA Results Based on Multiple Method Comparison. Presented at 53rd Annual Meeting, AACC/CSCC, 2001
Tube-Type Changes
Concurrent with the instrumentation changes, only the following tube types will be acceptable for certain tests:
Gold-Top Tubes: LH, PSA, Free PSA, TSH, and FreeT4
Red-Top Tubes: Total T3
Purple-Top Tubes: CEA
Serum/Plasma Reference Intervals
Olympus/Centaur to Architect/AxSym change 2005
|
Analyte(units) |
Current Reference Interval |
New Reference Interval |
|
Albumin(g/dL) |
3.5-5.7 |
3.5 – 5.0 |
|
Alk Phos(U/L) |
34-100 |
40-150 |
|
ALT(U/L) |
9-61 |
<55 |
|
Amylase(U/L) |
29-103 |
25-125 |
|
AST(U/L) |
13-39 |
<35 |
|
Conj. Bilirubin (mg/dL) |
Neonate: 0-0.6 Adult: 0-0.3 |
0.0-0.5 (all ages) |
|
Calcium(mg/dL) |
8.5-10.5 |
8.4 – 10.0 |
|
CEA(ng/mL) |
<5.0 |
No change |
|
Cholesterol (mg/dL) |
Male Female 0-19Y: <170 0-19Y: <175 >20Y: <200 20-29Y: <195 >30Y: <200 |
No change |
|
CK(U/L) |
32-237 |
Male: Female: 30-200 30-170 |
|
CK-MB(ng/mL) |
<5 |
Male: Female: <7.2 <3.4 |
|
Cl(mmol/L) |
98-107 |
No change |
|
CO2(mmol/L) |
Newborn: 13-22 Child: 18-27 Adult: 19-27 |
0-30d: 13-22 30d-18Y: 20-28 18Y-60Y: 22-29 >60Y: 23-31 |
|
Cortisol(µg/dL) |
Normal PM: 2-9 Dex suppression: <4 Cortrosyn Stimulation: >18 Critical value: <3 |
No Change |
|
Creatinine(mg/dL) |
Male: Female 0.7-1.3 0.6-1.2 |
Male: Female: 0.7-1.3 0.6-1.1 |
|
Estradiol(pg/mL) |
Male Female prepubertal:<20 prepubertal:<30 Adult: ND-56 Early Foll:30-65 Mid-foll: 30-130 Late-foll/midcycle: 50-320 Early lut: 20-100 Mid-lut: 30-200 Late lut: 20-160 Postmenop: ND-30 |
Male Female 11-44 Pre-pubertal: <20 Foll: 21-251 Mid-cycle: 38-649 Luteal: 21-312 Postmenop: <10-28 On HRT: <10-144 |
|
Ferritin(ng/mL) |
Male: Female 18-311 9-204 |
Male: Female 20-250 10-120 |
|
Free PSA(ng/mL) |
|
% free: >25% |
|
Free T3(pg/mL) |
2.3-4.2 |
No change |
|
Free T4(ng/dL) |
0.8-1.8 |
0.7-1.5 |
|
FSH(mIU/mL) |
Male Female pre-pub: <9.0 pre-pub: <9.0 13-70Y:0.9-15.0 Foll: 1.1-9.6 >70:2.8-55.5 Mid-Cy: 2.3-20.9 Lut: 0.8-7.5 Postmenop:34.4-95.8 |
No change |
|
GGT(U/L) |
9-64 |
Male: Female: <55 <38 |
|
Glucose(mg/dL) |
0-13Y: 60-100 >14Y: 74-100 |
No change |
|
Haptoglobin(mg/dL) |
16-200 |
<12Y: 20-160 >12Y: 30-200 |
|
hCG(U/L) |
<10.0 |
<5.0 |
|
HDL(mg/dL) |
Male: Female: 0-19Y: 30-65 0-19Y: 30-70 20-29Y: 35-70 20-29Y: 35-75 >30Y: 30-65 30-39Y: 35-80 40-49Y: 40-95 >50Y: 35-85 |
No change |
|
Iron(µg/dL) |
Male: Female 0-1Y: 40-100 0-1Y: 40-100 1-11Y: 50-120 1-11Y: 50-120 >11: 50-160 >11Y: 40-150 Toxic: >300 |
Male Female 30-145 25-160
Toxic: >300 |
|
K(mmol/L) |
3.5-5.0 |
Male Female 3.5-4.5 3.4-4.4 |
|
Lactate(mmol/L) |
0.7-2.1 |
0.5-2.2 |
|
LDH(U/L) |
140-271 |
180-360 |
|
Lipase(U/L) |
11-82 |
8-78 |
|
LH(mIU/mL) |
Male Female pre-pub: <6.0 pre-pub: <6.0 20-70Y: 1.5-9.3 Foll: 1.9-12.5 >70: 3.1-34.6 Mid-Cyc:8.7-76.3 Lut : 0.5-16.9 Postmenop:5.0-52.3 |
No change |
|
Mg(mg/dL) |
1.9-2.7 |
1.6-2.6 |
|
Na(mmol/L) |
135-145 |
136-145 |
|
NH3(µmol/L) |
11-35 |
11-32 |
|
Phos(mg/dL) |
Child: 4.0-7.0 Adult: 2.5-5.0 |
0-6d: 4.5-9.0 7d-24m 4.5-6.7 24m-12y 4.5-5.5 12Y-18Y: 2.3-4.7 >19Y: 2.3-4.7 |
|
Progesterone(ng/mL)
|
Male Female ND-0.6 early/mid Fol:0.2-1.1 Lat foll/Mid: 0.2-1.7 Early lut: 0.4-14 Mid lut: 4.5-20 Lat lut: 1.0-14 Postmenop: ND-0.7
1st trim : 8.1-42 2nd trim : 15.2-130 3rd trim : 49.1-227 |
Male Female <0.2 early/mid Fol:0.2-1.1 Lat foll/Mid: 0.2-1.7 Early lut: 0.4-14 Mid lut: 4.5-20 Lat lut: 1.0-14 Postmenop: <0.2
1st trim : 8.1-42 2nd trim : 15.2-130 3rd trim : 49.1-227 |
|
Prolactin(ng/mL) |
<20 |
No change |
|
PSA(ng/mL) |
Male Female: <40Y: <4.0 <4.0 40-50Y: <2.5 50-60Y: <3.5 60-70Y: <4.5 >70Y: <6.5 |
No change |
|
T Uptake |
23-37 |
0.69-1.41 T Uptake units |
|
Total Bilirubin(mg/dL) |
Newborn: <12.9 Adult:0.3-1.2 |
No change |
|
Total Protein(g/dL) |
6.0-8.3 |
0-6d: 4.6-7.0 7d-<7M: 4.4-7.6 7M-12M: 5.1-7.3 1Y-2Y: 5.6-7.5 >3Y-18Y: 6.0-8.0 18Y-60Y: 6.0-8.3 >60Y: 5.8-6.1 |
|
Total T3(ng/dL) |
60-180 |
58-159 |
|
Total T4(µg/dL) |
4.5-10.9 |
4.9 – 11.7 |
|
Transferrin(mg/dL) |
213-360 |
Male: Female <60Y:190-315 <60Y: 200-340 >60Y: 130-315 >60Y: 140-330 |
|
Triglycerides(mg/dL) |
Male: Female: 0-19: 30-140 30-140 20-29: 45-250 40-170 30-39: 50-320 40-195 40-49: 55-320 45-230 50-59: 60-300 55-250 >60: 55-260 60-240 |
No change |
|
Troponin I(ng/mL) |
<0.1 |
<0.02 |
|
TSH(mU/L) |
0.45-4.50 |
No change |
|
Urea(mg/dL) |
7-25 |
<3Y: 5-17 4-13Y: 7.0-17 14-18Y: 8-21 Male Female 19-<50Y: 8.9-20.6 7.0-18.7 >50Y: 8.4-25.7 9.8-20.1 |
|
Uric Acid(mg/dL) |
3.3-8.7 |
Male: Female 3.5-7.2 2.6-6.0 |
Urine/CSF Reference Interval Summary - Olympus/Centaur to Architect change 2005
|
Analyte |
Current Reference Interval |
New Reference Interval |
|
Na - Spot |
Diet Dependent |
No change |
|
Na – 24 Hr |
Diet Dependent |
40-290 mmol/24 Hr |
|
K - Spot |
Diet Dependent |
No change |
|
K – 24 Hr |
Diet Dependent |
25-125 mmol/24 hr |
|
Mg- Spot |
Diet Dependent |
No change |
|
Mg – 24 Hr |
Diet Dependent |
6.0-10.0 mg/24 Hr |
|
Phos - Spot |
Diet Dependent |
No change |
|
Phos – 24 Hr |
Diet Dependent |
0.1-1.3g/24 Hr |
|
Uric Acid - spot |
Diet Dependent |
No change |
|
Uric Acid – 24 Hr |
Diet Dependent |
No change |
|
Amylase |
5-27 U/24 Hr |
No Change |
|
Amy/Creat Clear |
1.3-4.2% |
No change |
|
Ca |
100-300 mg/24 Hr |
Diet Dependent |
|
Cl |
None determined |
Diet Dependent |
|
Creatinine |
Male: 0.8-2.8 g/24hr Female: 0.8-1.8 g/24hr |
No change |
|
Urine Total Protein - spot |
<119 mg/24hr |
10-140 mg/L |
|
Urine Total Protein – 24 Hr |
<119 mg/24H |
<100 mg/24 Hr |
|
Myoglobin |
Negative |
No change |
|
|
||
|
CSF Protein (mg/dL) |
Lumbar: 12-40 Ventricular: 8-15 |
Lumbar: 15-25 Ventricular: 5-15 |
|
CSF Glucose (Mg/dL) |
12-60 |
0-12Y:60-80 >12Y: 40-70 |
|
CSF Lactate (mmol/L) |
0.8-2.8 |
0.5-2.2 |
Therapeutic Drug Reference Interval Summary - Olympus/Centaur to Architect/AxSym change 2005
No changes to be made in either total or “free” drugs as these are therapeutic targets established by clinical practice.