Patrick J. Parsons, PhD Chief, Laboratory of Inorganic and Nuclear Chemistry Wadsworth Center, New York State Dept of Health, Albany, NY Chair Laboratory.

Patrick J. Parsons, PhD

Chief, Laboratory of Inorganic and Nuclear ChemistryWadsworth Center, New York State Dept of Health, Albany, NY

Chair

Laboratory Workgroup (LWG)Advisory Committee on Childhood Lead Poisoning Prevention (ACCLPP)

July 25, 2013

Update from the ACCLPP Laboratory Workgroup

Laboratory Workgroup Membership

Chair Patrick J. Parsons, PhD, FRSC (NYS DOH)

Members Valerie Charlton, MD, MPH (CA DOH / CLPPB)Leland McClure, PhD, D-ABFT (Quest

Diagnostics)Megan Sandel, MD, MPH (Boston Medical

Center) Donald Simmons, PhD (UIHL)Noel Stanton, MS (WSLH)

CDC SMEs Walter Alarcon, MSc, PhD (CDC / NIOSH)Mary Jean Brown, ScD, RN (CDC / NCEH)Jeffery M. Jarrett, MS (CDC / NCEH)Robert L. Jones, PhD (CDC / NCEH)

Patrick J. Parsons, PhD

Chief, Laboratory of Inorganic and Nuclear ChemistryWadsworth Center, New York State Dept of Health, Albany, NY

Chair

Laboratory Workgroup (LWG)Advisory Committee on Childhood Lead Poisoning Prevention (ACCLPP)

July 25, 2013

Recommended standards of practice for those using

point of care blood lead testing

Charge #2 to Laboratory Workgroup

The WG should address the need for recommended standards of practice for those using point of care blood lead testing.

* ACCLPP, October 2009

Laboratory Workgroup Meetings

Web Conferences / Conference Calls February 7, 2011 April 8, 2011 June 13, 2011 August 24, 2011 September 27, 2011

Finalized questions for Magellan Biosciences October 17, 2011

Q/A with Magellan Biosciences November 23, 2011 October 1, 2012 - revised practice standards

Guidance

Based on the New York State Department of Health’s Clinical Laboratory Evaluation Program Blood Lead Practice Standards for Screening Tests Only

Divided into Statements of Guidelines Guidance in Interpretation

Guidelines 1a, 1b, 2, 3 and 4Contamination Control

Work area (1a, 1b)-Universal Precautions

Contamination Control in the Work Area

Materials and Specimen collection Preparing the skin collection site prior to capillary skin

puncture

Sample Processing

Guideline 5Use of Capillary Blood from a

Fingerstick

Guideline Ensure no air gaps present in the capillary

Guidance Appropriate for screening purposes only Typically used with a POC device Consult the manufacturer’s directions

Guideline 6Use of Venous Blood

Guideline Ensure the quality of the blood specimen

Guidance Preferred for blood lead testing purposes Use only EDTA or heparin as anticoagulants Other issues: Fill volume, mixing prior to

aliquoting, and monitoring for blood clots

Blood specimens with visible clots should be rejected

Guidelines 7 through 111

Re-emphasize the manufacturer’s directions:

6) Storage requirements7) Operating requirements8) Power source considerations *9) Use of test kit components10) Instrument Calibration

* based on use of POC analyzers in CDC field studies

Guideline 11Analysis of Quality Control (QC)

Materials

Guideline Ideally

Two clinically significant levels each analytical run At a minimum

Two clinically significant levels• Each new test kit lot• Each new shipment• Each new operator (two weeks)• When problems are suspected or identified

Guidance Frequency of QC should reflect volume of

testing

Guideline 13Repeat Testing of the Original

SpecimenGuideline If initial result ≥ 5 µg/dL (at or above the

current Reference Value), reanalyze (if volume permits) Original specimen Purpose is to rule out possible contamination error

Guidance If insufficient volume, e.g. capillary specimen,

report initial result and refer patient for confirmatory testing

Guideline 13Repeat Testing of the Original

SpecimenGuideline (continued) Resolve large discrepancies, if possible

EITHER additional analysis

OR report test results as inconclusive, with comment• insufficient specimen to repeat the analysis• refer patient for confirmatory testing

Guideline 13Repeat Testing of the Original

SpecimenGuidance Acceptable differences in repeats

5 to 20 µg/dL 3 µg/dL 21 to 40 µg/dL 4 µg/dL over 40 µg/dL 10%

Discard outliers Report average of two remaining values Refer patient for confirmatory testing

For any result exceeding 5 µg/dL if there is any uncertainty in the validity of the test

Guideline 13Confirmatory Testing

Guideline If blood lead ≥ 5 µg/dL the laboratory

must refer for a confirmatory test either:

a. the patient; orb.the venous blood specimen

Guidance Level of 5 µg/dL selected to

Maximize identification of children with levels ≥ reference value for blood lead

Guideline 14Confirmatory Testing

Referring patient

Preliminary results may be released with a comment initial test result is for screening purposes only confirmatory testing results are pending

Guideline 14Confirmatory Testing

Referring venous blood

Confirmatory testing by CLIA-certified laboratory Method categorized by CLIA as high complexity

Preliminary results may be released with a comment that results of confirmatory testing are pending

Unopened venous specimen is preferable

Guideline 15Reporting 5 – 10 µg/dL on Patient

ReportsGuideline Reference ranges must indicate that BLLs 5-

9 mg/dL have been associated with adverse health effects in children aged 6 years and younger

Guidance Reports should not indicate that

BLLs < 10 µg/dL are “normal”

This Guideline is now redundant given the change in definition of elevated and should be deleted

Guideline 16Reporting Requirements

Guideline Report all blood lead results to the proper

state or federal agency.

Guidance Essential

for proper follow-up for public health surveillance

Variations by state Data, timeframes, and mechanisms

Guideline 17Reporting Potential Contamination

Guideline Indicate possible false positive when

specimen is received in a container not known to be lead-free

Guidance No need to footnote in report for containers

cleared through in-house lot-testing.

Guideline 18Method Comparison

Guideline Periodically compare POC BLLs with

confirmations

Guidance Acceptable differences

5 to 20 µg/dL 3 µg/dL 21 to 40 µg/dL 4 µg/dL over 40 µg/dL 10%

Periodically review personnel competency reviews performance of quality control and proficiency testing

Guideline 19Quality Assurance (external QA)

Guideline Participation in proficiency testing provides

valuable assessment of analytical performance

Guidance no federal requirement for CLIA waived *

but highly recommended

*Some states do require regular participation in proficiency testing to receive reimbursement for test costs (e.g. CA, WI).

Other issues under consideration by the Lab Workgroup

Charge #3 Alternate matrices for assessing lead exposure

The WG should investigate and report to the ACCLPP on the efficacy, reliability and validity of measuring lead in saliva as an index of lead exposure. To a lesser extent, the WG should investigate report to the ACCLPP on the reliability and validity of measuring lead in other non traditional matrices such as sweat, hair, nails and packed red cells as indices of lead exposure

Other issues under consideration by the Lab Workgroup

Charge #4 Environmental lead analytical issues

The WG should investigate and report to the ACCLPP on the reliability of current technologies for assessing the lead content of paint, plastics and other environmental samples, laboratory capacity and capability for handling

Examples:• Hand held XRF use for assessing Pb in consumer products• Use of area concentrations (µg/cm2) versus mass fractions

(ppm or mg/kg)

Other issues under consideration by the Lab Workgroup

Charge #5 Reference intervals for adult lead exposure

The WG should investigate and report to the ACCLPP on how clinical laboratories should report the reference interval for adult lead exposure. Currently, many labs report <30 µg/dL, <20 µg/dL as “normal” for adult blood lead levels

Thank You

Questions?