Www.militaryblood.dod.milUNCLASSIFIED Evaluation of Rapid Screening Methods for Emergency Blood...

transcript

www.militaryblood.dod.mil UNCLASSIFIEDwww.militaryblood.dod.mil UNCLASSIFIED

Evaluation of Rapid Screening Methods for Emergency

Blood Collections

CPT Robert Gates, USACPT Robert Gates, USAArmed Services Blood Program Update Armed Services Blood Program Update

12 February 200812 February 2008

• Goal and ObjectivesGoal and Objectives• BackgroundBackground• Biokit evaluationBiokit evaluation• ConclusionConclusion• Other Tests-preliminary results (RV 236)Other Tests-preliminary results (RV 236)

Agenda

Minimize TTD risk related to transfusion of Minimize TTD risk related to transfusion of freshly collected blood products in theatrefreshly collected blood products in theatre

Objectives

• Rigorously evaluate the HCV and HBsAg rapid tests currently in use in theatre

• Assess all other candidate tests for future use

Background• >250 freshly collected blood products are transfused

into patients at US medical installations in OIF/OEF monthly

• Questionnaires and screening are either not performed or conducted in substandard fashion

• HIV, HCV, and HBV are rare but present in donors• Rapid testing offers opportunity to mitigate risk

Biorapid Evaluation

Biorapid EvaluationKit Insert Data

Biorapid HCV Biorapid HBsAg

Sensitivity .994 (.969-.999)

(N=176)

“able to detect HBsAg concentrations of 5IU/ml or higher”

Specificity .987 (.973-.995)

(N=472)

“>98% in studies with blood donors’ samples”

Storage Temp. 2-25C 2-8CTesting Temp. “Room Temp.” “Room Temp.”

Sample Types S, P, WB S, P

Volume Needed 25µl 125µl

Biorapid Evaluation

Gold Standard EIA

Biorapid HCV

- 23 13

Aggregate data from:WWHV301PHV106PHW804

Sensitivity = .281 (.138-.468)

Negative Likelihood Ratio (LR-) = .719

Specificity = 13/13 = 1.00 (.794-1.00)

Biorapid Evaluation

Gold Standard EIA

Biorapid HBsAg

- 43 8

Aggregate data from:PHA106PHA206PHA808

Sensitivity = .157 (.070-.286)

Specificity = 8/8 = 1.00 (.688-1.00)

HCV HBV

Biorapid Evaluation

Gold Standard EIA

Biorapid HCV + 42 0

- 8 50

Aggregate data from:American Red Cross samplesRoberson Donor Centersamples

Sensitivity = .84 (.709-.928)

Specificity = 13/13 = 1.00 (.929-1.00)

Biorapid Evaluation Gold Standard EIA

Biorapid HBsAg

+ 35 0

- 5 42

Aggregate data from:

American Red Cross samples

Roberson Donor Center

samples

Sensitivity = .875 (.730-.889)

Specificity = 8/8 = 1.00 (.916-1.00)

* 18 Invalid tests

Conclusions Biorapid Evaluation• Biorapid preformed poorly against panel specimens,

but had no invalid results• Also poor against clinical samples (84% sensitivity for

HCV, 87.5% sensitivity for HBsAg) and had an 18% invalid rate with the HBsAg test

• Conclusion: Biorapid hepatitis rapid tests should be replaced by tests that perform better

RV 236

• Seeks to identify best rapid assays for HCV and HBsAg• Tests selected based on published material, paring down from 30 HBsAg, and 29 HCV to 6 HCV and 4 HBsAg• Positive plasma down selection (N=50 per test) complete• Selected tests will be challenged in three stages:

-commercial panels (N = 54)-clinical samples (N = 672)-whole blood spiked with reactive plasma (N = 168)

• Ease of Use Survey

0102030405060708090

% Sensitivity

OraSure Alfa AT First Axiom CORE MedMira

Rapid test

Observed Sensitivity HCV Test

* Sensitivity statistically superior Compared to Biorapid

0102030405060708090

% Sensitivity

OraSure Alfa AT First Axiom CORE MedMira BIORAPID

Rapid Test

Observed Sensitivity

HCV Test Invalid Rate

0102030405060708090

Rapid Test

Observer 1

Observer 2

EOU Breakdown (HCV)

Rapid kits

EOU HCV Reading

EOU Breakdown (HCV)

Rapid kits

EOU HCV Interpreting

EOU Breakdown (HCV)

Rapid Kits

EOU HCV Learning

EOU Breakdown (HCV)

Rapid Kits

EOU HCV Overall

DOWN SELECTION TEST DATA (HCV)

Rapid Assay Observed Sensitivity (%), 95% CI *

Thermo stability (C)

Overall Ease of Use

Run Time (Minutes)

OraSure(OraQuick) 100, 94.2-100. Up to 30 5 20

AT FIRST (FIRST VUE) 100, 94.2-100 4-30 4 10

ALFA (Instant View) 100, 94.2-100 15-30 4 10

Axiom (axiom HCV) 98, 89.4-99.9 2-30 4 10

Core (Core HCV) 98, 89.4-99.9 4- 30 3 15

MedMira (MiraWell) 100**, 93.3-100 2-30 2 3

Biokit (Biorapid) 84, 70.9-92.8 2-25C/RT N/A 15

*Sensitivity based on small sample group (n=50),** 7/50 invalids (14%)

% Sensitivity

At First Axiom CORE Minerva

Rapid Test

Observed Sensitivity HBsAG Test

Observed Sensitivity

0102030405060708090

At First Axiom CORE Minerva BIORAPID

Rapid Test

% Sensitivity

HBsAg Test Invalid Rate

0102030405060708090

Rapid Test

Observer 1

Observer 2

EOU Breakdown (HBsAg)

Rapid Kits

EOU HBsAg Reading

Rapid Kits

EOU HBsAg Interpreting

Rapid Kits

EOU HBsAg Learning

Rapid Kits

EOU HBsAg Overall

PRELIMINARY DOWN SELECTION TEST DATA (HBsAg)

Rapid Assay Observed Sensitivity (%), 95% CI *

Thermo stability (C)

Overall Ease of Use

Run Time (Minutes)

AT FIRST (FIRST VUE) 92,80.8-97.8 4-30 5 15

Axiom (Axiom HBsAg) 84**,70.3-92.7 2-30 4 15

Core (Core HBsAg) 90,78.2-96.7 4-30 4 15

MINERVA 98*** ,88.7-99.9 15-34 4 15

Biokit (Biorapid)* 87.5****, 73-88.9 2-8/RT N/A 15

*Sensitivity based on small sample group (n=50),** 1/50 invalid (2%),***3/50 invalid (6%),****18/100 invalid (18% based on n=100)

Questions

OraSure(OraQuick)

Alfa( Instantview)

AT First(FIRST VIEW)

Axiom CORE MedMira (MiraWell)

Test Kits

Ease of use survey (HCV)

QUESTION 4

QUESTION 5

QUESTION 6

QUESTION 9

AT First (FIRST VIEW) Axiom CORE Minerva (Vscan)

Test kits

Ease of use survey (HBsAg)

QUESTION 4QUESTION 5QUESTION 6QUESTION 9

Www.militaryblood.dod.milUNCLASSIFIED Evaluation of Rapid Screening Methods for Emergency Blood...

Documents