Multidisciplinary management of anti‐PP1P^k or anti‐P alloimmunization during pregnancy: A new case with anti‐P and a literature review

Abstract

Background Red blood cell alloimmunization is the first cause of fetal and neonatal anemia. Alloimmunizations with anti‐PP1Pk or anti‐P can cause recurrent miscarriages and hemolytic disease of the fetus and newborn in the 2nd and 3rd trimesters of pregnancy. We report on a pregnant patient immunized with anti‐P and a history of recurrent miscarriages. Case Report This P2k (GLOB:‐1; P1PK:‐1,3) patient had a first pregnancy marked by a caesarean at 38 weeks of gestation (WG) for non‐reassuring fetal heart rate. Then, she had three early spontaneous miscarriages. The fifth pregnancy began with a high titer of anti‐P at 128. Early initiation of treatment with Intravenous Immunoglobulins (IVIg) and plasma exchanges (PE) starting at 5 WG permitted us to reduce the titer of anti‐P below 32. A healthy infant was delivered by caesarean at 38 WG without anemia at birth and no exchange transfusion was required. Discussion and Review of the Literature The P and Pk antigens are expressed on placental, trophoblastic, and embryonic cells. This explains why P1k (GLOB:‐1; P1PK:1,3), P2k (GLOB:‐1; P1PK:‐1,3), or Tj(a‐)/p (GLOB:‐1; P1PK:‐1,‐3) patients are prone to recurrent abortions in the first trimester of pregnancy. A literature review demonstrated 87% (68/78) of miscarriages in p patients. However, publication biases are possible with the most severe cases being reported. Conclusion Immunizations to P and PP1Pk antigens differ from others in their physiopathology and precocity. The association of PE and IVIg seems to be an effective treatment in the management of anti‐PP1Pk or anti‐P fetomaternal incompatibilities.

Recurrent miscarriage associated with rare anti-PP1Pk antibody: a case series and literature review

“…The anti-PP1Pk antibody is found in the serum of individuals with the p phenotype, one reason for RSA in pregnancy. A previous study reported that the P antigen was higher in the placenta than in fetal erythrocytes [9]. Currently, there is no speci c treatment for recurrent miscarriage associated with anti-PP1Pk antibody positivity at home and abroad.…”

Correlation Between the Presence of Antinuclear Antibodies and Recurrent Pregnancy Loss: A Mini Review

“…Several reports have suggested that plasmapheresis may also treat pregnant women with anti-phospholipid syndrome ( 76 , 77 ). For women with RPL, plasmapheresis was used to prevent future miscarriage in pregnant women immunized with anti-P or anti-PP1Pk and a history of RPL ( 78 , 79 ). However, as far as we are aware, there is no study reporting the use of plasmapheresis in RPL women with positive ANAs.…”

Identification of a novel P1PK allele (A4GALT*c.1‐504_1044del1548) in two Chinese sisters with a history of recurrent spontaneous abortion

“…Cytotoxic IgM and IgG3 antibodies against P and/or P k antigens are associated with a very high rate of spontaneous abortion in women with p, P 1 k , and P 2 k phenotypes, particularly in the first trimester. It is likely due to the high expression of P and P k antigens on the placenta, which might be the primary target of the antibodies 4 …”

“…It is likely due to the high expression of P and P k antigens on the placenta, which might be the primary target of the antibodies. 4…”