Fetale und neonatale Alloimmunthrombozytopenie – Pathophysiologie, Diagnostik, Therapie

Bei der fetalen und neonatalen Alloimmunthrombozytopenie (FNAIT) immunisiert sich die Schwangere gegen väterliche Merkmale auf den fetalen Thrombozyten. Der diaplazentare Übergang dieser Antikörper in den Fetalkreislauf führt zur Thrombozytopenie des Feten oder Neugeborenen. Eine gefürchtete Komplikation der FNAIT ist die intrakranielle Blutung. Für immunisierte Frauen mit erneutem Kinderwunsch ergeben sich besondere Implikationen. Die FNAIT ist daher ein Krankheitsbild, das der interdisziplinären Beratung und Behandlung unter Beteiligung von Frauenärzten, Pädiatern und Transfusionsmedizinern bedarf. Inzidenz, Pathogenese und Krankheitsbild der FNAIT werden dargestellt und die diagnostischen und therapeutischen Möglichkeiten anhand der aktuellen Studienlage diskutiert.

In fetal / neonatal alloimmune thrombocytopenia (FNAIT), antibodies are formed by the mother against paternal antigens present on fetal platelets. These antibodies will cause thrombocytopenia of the fetus or newborn when transferred via the placenta into the circulation of the unborn. Intracranial bleeding is one severe complication in FNAIT. In immunized females, a subsequent pregnancy may need special diagnostic and prophylactic interventions. Thus, FNAIT requires interdisciplinary counselling and treatment involving specialists for obstetrics, paediatrics, and transfusion medicine. The incidence, the pathogenesis, and the clinical picture of FNAIT will be described in this review. The diagnostic and therapeutic options are discussed and recent studies in the field are appraised.

Key words

NAIT - neonatal alloimmune thrombocytopenia - FNAIT - diagnosis - therapy

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