OPTN Kidney Paired Donation
(KPD) Histocompatibility Testing
Policies
Kidney Transplantation Committee
Spring 2014
Background

Kidney Committee distributed KPD policies for
public comment in March 2012

A number of commenters had concern with histo
section due to missing requirements

Professional societies brought together a KPD
consensus conference around same time

This proposal incorporates
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spring 2012 OPTN public comment feedback
findings from KPD consensus conference
recommendations from OPTN Histo Committee
The Problem

Low match success rate in KPD program

Antibody related issues and positive crossmatches
continue to account for a number of match failures

Insufficient histocompatibility testing requirements
to prevent match failure
Goal of the Proposal

Increase match success rate in KPD program by
preventing unexpected positive crossmatches that
can break chains and prevent candidates and
donors from accessing subsequent match runs and
transplant opportunities

Promote transplant safety through more effective
screening of kidney offers
Proposed: HLA Typing

Molecular HLA typing required for donors and
candidates

Loci required for donors: HLA-A, B, Bw4, Bw6, C, DR,
DR51, DR52, DR53, DPB, DQA, DQB

Loci required for candidates: HLA-A, B, Bw4, Bw6, DR

If candidate has unacceptable antigens, additional loci
required: C, DR51, DR52, DR53, DPB, DQA, DQB

Candidate’s hospital must retype donor to confirm HLA
type
Proposed: Antibody Screenings

Candidate’s transplant hospital must screen for
antibodies at all of the following times:


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every 90 days
when potentially sensitizing event occurs
if candidate reactivated after more than 90 inactive days
if unacceptable positive crossmatch occurs that prevents transplant with
matched donor

Labs must use method at least as sensitive as
crossmatch method

Physician/surgeon (or designee) and lab director (or
designee) must review and confirm UA’s listed for
candidate
Proposed: Crossmatching

Candidate’s transplant hospital must perform physical
crossmatch before donor’s nephrectomy is scheduled

Must report crossmatch results to donor’s transplant
hospital and UNOS

If unacceptable positive crossmatch occurs between
candidate and matched donor, candidate’s hospital
must inactivate candidate before next match run,
review the unacceptable antigens (UA), and report
reason to UNOS w/in 7 days

Candidate can be reactivated once review and update
(if applicable) of UAs is complete
Supporting Evidence

Crossmatch-related refusals (postive crossmatch
or unacceptable antigens) account for ~30% of
failed matches

61 programs had accepted at least one match offer
for which the entire exchange fell through

Some programs may have had a disproportionately
high number of crossmatch-related refusals

39 programs refused at least one match offer due
to a crossmatch-related reason
Specific Feedback Request

If unacceptable positive crossmatch occurs
between candidate and matched donor,
candidate’s hospital must inactivate candidate in
the KPD program before next match run

If this change is approved, is it less burdensome for
transplant programs if the inactivation is automatic
(completed by UNOS)?
Specific Feedback Request

Is it burdensome to require antibody screenings
every 90 days for ALL candidates (even if not
sensitized?)

Should longer timeframe between screenings apply
for non-sensitized candidates?

180 days?
What Members will Need to Do

Donor’s transplant hospital responsible for
reporting donor HLA info, arranging shipment of
donor blood sample to candidate’s hospital or histo
lab

Candidate’s transplant hospital responsible for
reporting candidate HLA info, confirming donor HLA
info, antibody screening requirements,
crossmatching requirements
Questions?

Mark Aeder, MD
KPD Work Group Chair
mark.aeder@uhhospitals.org

Name
Region # representative
Email

Gena Boyle
Committee Liaison
gena.boyle@unos.org