Transfusion supply of chronically transfusion dependent patients: antigen-, rare blood type and ethnicity-related challenges

Transcription

1 Thierry PEYRARD PharmD, PhD, EurClinChem National Institute of Blood Transfusion - Paris French National Immunohematology Reference Laboratory Transfusion supply of chronically transfusion dependent patients: antigen-, rare blood type and ethnicity-related challenges

2 I declare no conflict of interest related to this presentation

3 ETHNIC POPULATION BACKGROUND IN FRANCE France: 66 million inhabitants Ethnically mixed population o o Overseas territories Migrant people from former French colonies of Africa

4 POPULATION BACKGROUND Former French colonies of Africa p, P k Ge:-2,3, Lan- Jk(a-b-) RH:-46 (R N R N ) Fy(a-b-) Hr S - (RH:-18) Hr B - (RH:-34) RH:-57 [cejal/cejal] RH:-61 (cemo/cemo) Js(b-) At(a-) S-s-U- S-s-U+ var

5 POPULATION BACKGROUND U-/U+ var, Js(b-) Hr S -, Hr B - Jk:-3 D, dccee (r y r y ) U-/U+ var U-/U+ var, Bombay, Dantu, Hr S -, Hr B -, RH:-61 (cemo/cemo) Jk:-3 Sc:-3 French overseas territories

6 SICKLE CELL DISEASE IN FRANCE Sickle cell disease (SCD) is the most frequent genetic disease in France ( 15,000 patients) This number is expected to double by the next 15 years Patients often transfused and at high risk of developing RBC alloantibodies Many rare blood types in people of African descent (Rh, MNS, Kell, Dombrock, etc.) => national rare blood bank

7 ACTIVITY OF THE FRENCH NATIONAL RARE BLOOD BANK ~ 6,500 frozen RBC units (-80 C) from 1,800 donors 300 rare RBC units delivered per year (80 patients) 30% of rare RBC units transfused to sickle cell disease patients 5% of RBC units shipped abroad

8 The -80 C freezers ( in back-up) at the French National Rare Blood Bank ( 6,500 frozen RBC units)

9 ACTIVITY WITHIN THE LAST 3 YEARS 854 THAWED RARE RBC UNITS Peyrard T. Immunohematology 2016

10 46 UNITS SHIPPED ABROAD 2013/ /10 2 O, Js(b-) RBC units Most requests for patients of African ancestry

11 THE S-s- RARE BLOOD TYPE Mean prevalence in Africans is 1-2% but may reach up to 40% in equatorial Africa Highest gap between supply and demand in France 8% of the requested rare units within the last 3 years Also becomes a major problem in several European countries

12 A FEW REMINDERS ON THE RARE S-s- BLOOD TYPE Several molecular backgrounds for the S-srare blood type encountered in Africans 50% are S-s-U- => total deletion of the GYPB gene (delgypb/delgypb) 50% are S-s-U+ var => weak and partial U All are able to develop anti-u, with the strongest examples found in S-s-U- S-s-U+ var donors are not compatible with the serum of S-s-U- patients

13 THE S-s- RARE BLOOD TYPE IN FRANCE 72 U- donors, all confirmed by genotyping => 227 frozen units 77 U+ var => 276 frozen units

14 THE S-s- RARE BLOOD TYPE 343 patients with alloanti-u reported Major difficulties when patients are U- and also: C-e- (R 1 R 1 ): 2 donors O, D-: 8 donors e-: only one active donor, group B

15 THE S-s CHALLENGE ~20% of our S-s- rare RBC units come every year from the Martinique Island, in the Caribbean sea!

16 THE S-s- RARE BLOOD TYPE 18 reported cases of S-s- people type with a second additional rare type! First rare specificity Second rare specificity Number of cases Number of frozen units Comments U- Hr S - (RH:-18) 1 0 Anti-U and anti-hr S U- Hy- 1 0 U- Js(b-) 1 0 U- R N R N (RH:-46) 8 1 U- Jo(a-) 2 1 One case with anti-u U+ var Hy- 2 2 One case with anti-u U+ var Js(b-) 1 0 U+ var Jo(a-) 1 0

17 DUFFY ANTIBODIES IN Fy(a-b-) Data from the French National Registry 160 Fy(a-b-) patients with anti-fy3 142 Fy(a-b-) patients with anti-fy a (frequently precedes the making of anti-fy3) Anti-Fy3 with frequent hemolytic transfusion reactions reported => Fy(a-b-) RBC units required Anti-Fy a in a Fy(a-b-) patient => Fy(a-b-) RBC units required PATIENTS

18 WHICH TESTS DO WE PERFORM FOR SCD PATIENTS?

19 SEROLOGICAL TESTING Most people of African ancestry are D+C-E-c+e+, Fy(a-b-), Jk(a+b-), S-s+ Some antigens are very rare in Europeans but frequent in Africans (e.g. VS, Js a, D W, DAK, He, etc.) Low prevalence VS Js a D W DAK He Europeans "Balanced" prevalence Fy a : 66% High prevalence U

20 SEROLOGICAL TESTING Most people of African ancestry are D+C-E-c+e+, Fy(a-b-), Jk(a+b-), S-s+ Some antigens are very rare in Europeans but frequent in Africans (e.g. VS, Js a, D W, DAK, He, etc.) Low prevalence Africans "Balanced" prevalence DAK Fy a He D W VS U Js a High prevalence

21 SEROLOGICAL TESTING If RBC units are transfused in an intra-ethnic background, higher risk of developing anti-vs, anti-js a, anti-d W, etc., whilst not detectable by routine antibody screening => Systematic serological crossmatch is mandatory in France for SCD patients, whatever the background (age, gender, immunization status)

22 Significant prevalence of Rh variants of clinical relevance in people of African ancestry 10% of D+ are partial D 30% of C+ are partial C 3% of e+ are partial e 1% are Hr B - 1% are Hr S - GENOTYPING

23 GENOTYPING IN SCD PATIENTS New policy implemented in 2016: All SCD patients are subject to standard, RHD and RHCE genotyping, except those with 12 transfusion episodes (including at least one transfusion with D+ RBCs for R 0 R 0 patients) being non-alloimmunized (considered lowresponders ). S. Cohen & F. Pirenne (manuscript in preparation). This threshold value of 12 RBC units is consistent with a work published by a Dutch team in August 2016

24 Rh/K matched

25 STANDARD DNA-CHIP System Phenotype System Phenotype MNS U- DI Di(b-) U+ var SC Sc:-1 RH Hr B - LU Lu(b-) k- DO Hy- Jo(a-) KEL Kp(b-) CO Co(a-) Js(b-) LW LW(a-) 13 rare blood types simultaneoulsy screened in one single test (BeadChip HEA v1.2)

26 Two other DNA chips: RHD and RHCE RH*C cesl RH*E ceti RH*c cert RH*e cera RH*C w Ce-D(4)-Ce [R N ] RH*C x DHAR cear ceek cebi cemo [ce(667)] ce S [ce(733,1006] ce s [ce(733)] ce s (340) ce S (748) cecf r G CeMA CeVA CeVG E type I E type II (EKK) E type III E type IV EKH Example of the RHCE chip: 6 rare Rh blood types simultaneously screened in people of African descent Hr S - (RH:-18) Hr B - (RH:-34) R N R N (RH:-46) RH:-57 (RHCE*ceJAL/RHCE*ceJAL) RH:-58 (RHCE*ceCF/RHCE*ceCF) RH:-61 (RHCE*ceMO/RHCE*ceMO)

27 RH*C cesl RH*E ceti RH*c cert RH*e cera RH*C w Ce-D(4)-Ce [R N ] RH*C x DHAR cear ceek cebi (& cesm screening) cemo ce S r G CeMA CeVA CeVG E type I Two major limitations c.254c>g mutation (ceag) and heterozygous R N variants are not screened => 2 additional tests - SSP-PCR for R N screening in all C+ patients ce s ce s (340) ce S (748) cecf E type II (EKK) E type III E type IV EKH - SSP-PCR for RHCE*ce254G (RHCE*ceAG) screening RHCE*ceAG allele found at the heterozygous state in 17% (25/150) of a cohort of young SCD patients in France! (manuscript in preparation)

28 CASE STUDIES

29 CASE STUDY 1 36 yo patient of African origin Group O, D+C+E-c-e+, K- This Rh phenotype is very uncommon in Africans => at risk of being a rare Rh blood type named RH:-46 (R N R N )

30 High risk for R N R N (RH:-46) to be now overlooked with most column agglutination devices!

31 CASE STUDY 1 RH:-46 rare type confirmed by phenotyping and genotyping Extended phenotype performed Fy(a-b-), Jk(b-), M-N+S-s-! Genotyping to confirm if U- or U+ var

32 CASE STUDY 1 => Incidental finding of a rare Js(b-) type! => U- phenotype

33 This Fy(a-b-) patient shows three rare blood types! RH:-46 U- Js(b-) CASE STUDY 1 Probably the only one reported in the world! Not alloimmunized as of today

34 CASE STUDY 2 SCD patient, scheduled to undergo a complex surgery with bleeding risk A, D+C-E-c+e+, K-, Fy(a-b-), Jk(b-), M-N+S+s- Antibodies: anti-c, anti-e, anti-jk b, anti-m, anti-s Only 4 compatible blood donors in France!

35 CASE STUDY 3 SCD patient with severe crisis and anemia O, D+C-E-c+e+, K-, Fy(a-b-), Jk(a-), S-s-U+ var Anti-D (partial D), anti-jk a, anti-u Only 8% of Africans are Jk(a-) => one single compatible donor with one frozen unit!

36 CASE STUDY 4 Canadian SCD patient, severe anemia 10 alloantibodies! Anti-Fy3 Anti-E Anti-K Anti-Kp a Anti-Fy a Anti-Jk b Anti-S Anti-Do a Anti-Js a Anti-VS Two rare RBC units sent from Paris to Canada

37 CASE STUDY 5 87 yo patient from French Caribbean islands O, D-C+E-c-e+ (r r ) Anti-E, anti-c, anti-js b Patient confirmed to be Js(b-) No compatible donor in the world Transfusion necessary due to severe anemia Use of rare blood D-c- but Js(b+), with bolus of steroids and IV Ig infusion 8 hours before and 24 hours after incompatible transfusion Transfusion reported to be efficient

38 EXAMPLE OF AN ONGOING SUCCESSFUL MASS RARE DONOR SCREENING IN FRANCE

39 SCREENING FOR NEW DONORS WITH A RARE VEL- PHENOTYPE Anti-Vel clone SpG213Dc3

40 VEL- RARE DONOR SCREENING High-throughput Vel donor phenotyping on the PK7300 instrument since October 2015 in Northern France 600,000 donations tested 180 new Vel- donors identified! (3/10,000)

41 STOCK OF VEL- RBC UNITS IN FRANCE BEFORE THIS MASS RARE DONOR SCREENING 5 donors Total of frozen units: 19 Mass donor screening => 12 new Vel- donors O, D-C-E, K- 8 are < 30 years old

42 STOCK OF VEL- RBC UNITS IN FRANCE BEFORE THIS MASS RARE DONOR SCREENING 1 donor Total of frozen units: 9 Mass donor screening => 20 new Vel- O, E-c-, K- 7 are < 30 years old

43 ACKNOWLEDGMENTS THE NATIONAL IMMUNOHEMATOLOGY REFERENCE LABORATORY TEAM THE FRENCH NATIONAL RARE BLOOD BANK STAFF

44 THANK YOU FOR YOUR ATTENTION VIELEN DANK!