Suivi et traitement des allo-immunisations érythrocytaires en période prénatale

摘要

Red blood cell alloimmunisations remain the primary cause of foetal anaemia, a rare disease but with potentially serious consequences, including foetal hydrops, foetal hypoxic neurological lesions and, in worst-case scenarios, foetal or neonatal death. RhD incompatibilities are still the most common, followed by Kell and little c incompatibilities. The discovery of severe foetal anaemia can lead to the carrying out of an intravascular foetal blood transfusion in cases of early gestational age and/or hydrops, delivery of the foetus when the gestational age is advanced, which is possible with a moderately premature foetus, or a possible intraperitoneal transfusion during the very early stages of pregnancy. Intravascular foetal blood transfusions have transformed the prognosis for foetal anaemia and are now considered as a relatively safe procedure. The risk of a fatal procedure-related complication is estimated as being around 3%; this risk remains significant in cases of foetal anaemia that occur very early on, requiring transfusions to take place up to five or six times during the same pregnancy. Prognosis is also very dependent on how early the anaemia is diagnosed and how it is treated. The risk of death and foetal neurological complications is higher when the diagnosis is made at the hydrops stage than in cases of isolated anaemia.